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47 ud af 47 tidsskrifter valgt, søgeord (malaria) valgt, emner højest 180 dage gamle, sorteret efter nyeste først.
353 emner vises.
Malaria Journal, 11.11.2023
Tilføjet 11.11.2023
Abstract Background Malaria affects millions of Cameroonian children under 5 years of age living in the North and Far North regions. These regions bear the greatest burden, particularly for children under 5 years of age. To reduce the burden of disease in these regions, Cameroon adopted the Seasonal Malaria Chemoprevention (SMC) in 2016 and has implemented it each year since its adoption. However, no previous studies have systematically assessed the effects of this intervention in Cameroon. It is important to understand its effect and whether its implementation could be improved. This study aimed to assess the effect of SMC in Cameroon during the period 2016–2021 on malaria morbidity in children under 5 years of age using routine data. Methods Data on malaria cases were extracted from the Cameroon Health Monitoring Information System (HMIS) from January 1, 2011, to December 31, 2021. Health facilities report these data monthly on a single platform, the District Health Information System version 2 (DHIS2). Thus, a controlled interrupted time-series model in a Bayesian framework was used to evaluate the effects of the SMC on malaria morbidity. Results SMC implementation was associated with a reduction in the incidence of uncomplicated malaria cases during the high-transmission periods from 2016 to 2021. Regarding the incidence of severe malaria during the high-transmission period, a reduction was found over the period 2016–2019. The highest reduction was registered during the second year of implementation in 2017:15% (95% Credible Interval, 10–19) of uncomplicated malaria cases and 51% (47–54) of confirmed severe malaria cases. Conclusion The addition of SMC to the malaria intervention package in Cameroon decreased the incidence of uncomplicated and severe malaria among children under 5 years of age. Based on these findings, this study supports the wide implementation of SMC to reduce the malaria burden in Cameroon as well as the use of routine malaria data to monitor the efficiency of the strategy in a timely manner.
Læs mere Tjek på PubMedJournal of the American Medical Association, 11.11.2023
Tilføjet 11.11.2023
Man is associated with the atmosphere throughout his life. He breathes the air every minute of the day, and is more or less bathed by it. Accordingly, he has become adjusted to its chemical composition and physical properties under a variety of atmospheric conditions. Nevertheless, there are times when even to an organism so well adapted as is the animal body to its environment the air acquires properties that are commonly designated “bad.” The explanations of what constitutes “badness” in the air have gradually undergone changes with the progress of scientific inquiry. It is not so long ago that malaria was ascribed to objectionable conditions of the atmosphere per se. Only a few years since, the occasional “badness” of inside air, as in crowded rooms or meeting places, was attributed to an accumulation of an organic poison exhaled from the lungs. Carbon dioxid, an eliminated product of respiration, has also been charged with responsibility for harmful contamination of the atmosphere by occurring in supposedly excessive amounts; but neither the hypothetic respiratory poison nor the ever present carbon dioxid has sustained its acquired reputation as the dangerous factor in bad air.
Læs mere Tjek på PubMedMalaria Journal, 10.11.2023
Tilføjet 10.11.2023
Abstract Studies on the applications of infrared (IR) spectroscopy and machine learning (ML) in public health have increased greatly in recent years. These technologies show enormous potential for measuring key parameters of malaria, a disease that still causes about 250 million cases and 620,000 deaths, annually. Multiple studies have demonstrated that the combination of IR spectroscopy and machine learning (ML) can yield accurate predictions of epidemiologically relevant parameters of malaria in both laboratory and field surveys. Proven applications now include determining the age, species, and blood-feeding histories of mosquito vectors as well as detecting malaria parasite infections in both humans and mosquitoes. As the World Health Organization encourages malaria-endemic countries to improve their surveillance-response strategies, it is crucial to consider whether IR and ML techniques are likely to meet the relevant feasibility and cost-effectiveness requirements—and how best they can be deployed. This paper reviews current applications of IR spectroscopy and ML approaches for investigating malaria indicators in both field surveys and laboratory settings, and identifies key research gaps relevant to these applications. Additionally, the article suggests initial target product profiles (TPPs) that should be considered when developing or testing these technologies for use in low-income settings.
Læs mere Tjek på PubMedMalaria Journal, 10.11.2023
Tilføjet 10.11.2023
Abstract Background Seasonal malaria chemoprevention (SMC) using sulfadoxine-pyrimethamine plus amodiaquine (SP-AQ), is a community-based malaria preventive strategy commonly used in the Sahel region of sub-Saharan Africa. However, to date it has not been implemented in East Africa due to high SP resistance levels. This paper is a report on the implementation of SMC outside of the Sahel in an environment with a high level of presumed SP-resistance: five cycles of SMC using SPAQ were administered to children 3–59 months during a period of high malaria transmission (July–December 2019) in 21 villages in South Sudan. Methods A population-based SMC coverage survey was combined with a longitudinal time series analysis of health facility and community health data measured after each SMC cycle. SMC campaign effectiveness was assessed by Poisson model. SPAQ molecular resistance markers were additionally analysed from dried blood spots from malaria confirmed patients. Results Incidence of uncomplicated malaria was reduced from 6.6 per 100 to an average of 3.2 per 100 after SMC administration (mean reduction: 53%) and incidence of severe malaria showed a reduction from 21 per 10,000 before SMC campaign to a mean of 3.3 per 10,000 after each cycle (mean reduction: 84%) in the target group when compared to before the SMC campaign. The most prevalent molecular haplotype associated with SP resistance was the IRNGE haplotype (quintuple mutant, with 51I/59R/108N mutation in pfdhfr + 437G/540E in pfdhps). In contrast, there was a low frequency of AQ resistance markers and haplotypes resistant to both drugs combined (
Læs mere Tjek på PubMedMalaria Journal, 10.11.2023
Tilføjet 10.11.2023
Abstract Background Attractive targeted sugar bait (ATSB) is a novel approach to vector control, offering an alternative mode of insecticide delivery via the insect alimentary canal, with potential to deliver a variety of compounds new to medical entomology and malaria control. Its potential to control mosquitoes was recently demonstrated in major field trials in Africa. The pyrrole chlorfenapyr is an insecticide new to malaria vector control, and through its unique mode of action—disruption of ATP mediated energy transfer in mitochondria—it may have direct action on energy transfer in the flight muscle cells of mosquitoes. It may also have potential to disrupt mitochondrial function in malarial parasites co-existing within the infected mosquito. However, little is known about the impact of such compounds on vector competence in mosquitoes responsible for malaria transmission. Methods In this study, ATSBs containing chlorfenapyr insecticide and, as a positive control, the anti-malarial drugs artemether/lumefantrine (A/L) were compared for their effect on Plasmodium falciparum development in wild pyrethroid-resistant Anopheles gambiae sensu stricto (s.s.) and for their capacity to reduce vector competence. Female mosquitoes were exposed to ATSB containing either sublethal dose of chlorfenapyr (CFP: 0.025%) or concentrations of A/L ranging from 0.4/2.4 mg/ml to 2.4/14.4 mg/ml, either shortly before or after taking infective blood meals. The impact of their component compounds on the prevalence and intensity of P. falciparum infection were compared between treatments. Results Both the prevalence and intensity of infection were significantly reduced in mosquitoes exposed to either A/L or chlorfenapyr, compared to unexposed negative control mosquitoes. The A/L dose (2.4/14.4 mg/ml) totally erased P. falciparum parasites: 0% prevalence of infection in female mosquitoes exposed compared to 62% of infection in negative controls (df = 1, χ2 = 31.23 p
Læs mere Tjek på PubMedFrancis N. NkemngoLymen W. RaissaDaniel N. NgueteCyrille NdoJerome Fru-ChoFlobert NjiokouSamuel WanjiCharles S. Wondji1Centre for Research in Infectious Diseases (CRID), Yaoundé, Cameroon2Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea, Cameroon3Department of Biological Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon4Research Foundation in Tropical Diseases and Environment, Buea, Cameroon5Centre for Infection Biology and Translational Research, Forzi Institute, Buea, Cameroon6Vector Biology Department, Liverpool School of Tropical Medicine, Liverpool, United Kingdom, Audrey Odom John
Antimicrobial Agents And Chemotherapy, 10.11.2023
Tilføjet 10.11.2023
Malaria Journal, 10.11.2023
Tilføjet 10.11.2023
Abstract Background The increasing incidence of Plasmodium knowlesi malaria poses a significant challenge to efforts to eliminate malaria from Malaysia. Macaque reservoirs, outdoors-biting mosquitoes, human activities, and agricultural work are key factors associated with the transmission of this zoonotic pathogen. However, gaps in knowledge regarding reasons that drive malaria persistence in rural Kudat, Sabah, Northern Borneo remain. This study was conducted to address this knowledge gap, to better understand the complexities of these entangled problems, and to initiate discussion regarding new countermeasures to address them. This study aims to highlight rural community members’ perspectives regarding inequities to health relating to P. knowlesi malaria exposure. Methods From January to October 2022, a study using qualitative methods was conducted in four rural villages in Kudat district of Sabah, Malaysia. A total of nine in-depth interviews were conducted with community and faith leaders, after the completion of twelve focus group discussions with 26 photovoice participants. The interviews were conducted using the Sabah Malay dialect, audio-recorded, transcribed, and translated into English. The research team led the discussion and analysis, which was approved by participants through member checking at the community level. Results Participants identified disparity in health as a key issue affecting their health and livelihoods. Injustice in the social environment was also identified as a significant challenge, including the importance of listening to the voices of affected communities in disentangling the social and economic phenomena that can impact malaria control. Specific concerns included inadequate access to health-related resources and degradation of the environment. Participants recommended improving access to water and other necessities, increasing the availability of malaria control commodities in healthcare facilities, and developing sustainable programs to reduce socioeconomic disparities. Conclusion Inequities to health emerged as a key concern for malaria control in rural Kudat, Sabah. A locally targeted malaria programme cantered on improving the social and economic disparities associated with health outcomes, could be a potential strategy for malaria prevention in such areas. Community-level perspectives gathered from this study can be used as a foundation for future discussions and dialogues among policymakers and community members for achieving greater transparency, improving social equity, and interoperability in addressing P. knowlesi malaria control.
Læs mere Tjek på PubMedMalaria Journal, 9.11.2023
Tilføjet 9.11.2023
Abstract Background Several countries in Southeast Asia are nearing malaria elimination, yet eradication remains elusive. This is largely due to the challenge of focusing elimination efforts, an area where risk prediction can play an essential supporting role. Despite its importance, there is no standard numerical method to quantify the risk of malaria infection. Thus, there is a need for a consolidated view of existing definitions of risk and factors considered in assessing risk to analyse the merits of risk prediction models. This systematic review examines studies of the risk of malaria in Southeast Asia with regard to their suitability in addressing the challenges of malaria elimination in low transmission areas. Methods A search of four electronic databases over 2010–2020 retrieved 1297 articles, of which 25 met the inclusion and exclusion criteria. In each study, examined factors included the definition of the risk and indicators of malaria transmission used, the environmental and climatic factors associated with the risk, the statistical models used, the spatial and temporal granularity, and how the relationship between environment, climate, and risk is quantified. Results This review found variation in the definition of risk used, as well as the environmental and climatic factors in the reviewed articles. GLM was widely adopted as the analysis technique relating environmental and climatic factors to malaria risk. Most of the studies were carried out in either a cross-sectional design or case–control studies, and most utilized the odds ratio to report the relationship between exposure to risk and malaria prevalence. Conclusions Adopting a standardized definition of malaria risk would help in comparing and sharing results, as would a clear description of the definition and method of collection of the environmental and climatic variables used. Further issues that need to be more fully addressed include detection of asymptomatic cases and considerations of human mobility. Many of the findings of this study are applicable to other low-transmission settings and could serve as a guideline for further studies of malaria in other regions.
Læs mere Tjek på PubMedMalaria Journal, 9.11.2023
Tilføjet 9.11.2023
Abstract Background Identification of malaria vectors is an important exercise that can result in the deployment of targeted control measures and monitoring the susceptibility of the vectors to control strategies. Although known to possess distinct biting behaviours and habitats, the African malaria vectors Anopheles gambiae and Anopheles arabiensis are morphologically indistinguishable and are known to be discriminated by molecular techniques. In this paper, Raman spectroscopy is proposed to complement the tedious and time-consuming Polymerase Chain Reaction (PCR) method for the rapid screening of mosquito identity. Methods A dispersive Raman microscope was used to record spectra from the legs (femurs and tibiae) of fresh anaesthetized laboratory-bred mosquitoes. The scattered Raman intensity signal peaks observed were predominantly centered at approximately 1400 cm−1, 1590 cm−1, and 2067 cm−1. These peaks, which are characteristic signatures of melanin pigment found in the insect cuticle, were important in the discrimination of the two mosquito species. Principal Component Analysis (PCA) was used for dimension reduction. Four classification models were built using the following techniques: Linear Discriminant Analysis (LDA), Logistic Regression (LR), Quadratic Discriminant Analysis (QDA), and Quadratic Support Vector Machine (QSVM). Results PCA extracted twenty-one features accounting for 95% of the variation in the data. Using the twenty-one principal components, LDA, LR, QDA, and QSVM discriminated and classified the two cryptic species with 86%, 85%, 89%, and 93% accuracy, respectively on cross-validation and 79%, 82%, 81% and 93% respectively on the test data set. Conclusion Raman spectroscopy in combination with machine learning tools is an effective, rapid and non-destructive method for discriminating and classifying two cryptic mosquito species, Anopheles gambiae and Anopheles arabiensis belonging to the Anopheles gambiae complex.
Læs mere Tjek på PubMedMalaria Journal, 9.11.2023
Tilføjet 9.11.2023
Abstract Background Malaria vectors vary in feeding preference depending on their innate behaviour, host availability and abundance. Host preference and human biting rate in malaria vectors are key factors in establishing zooprophylaxis and zoopotentiation. This study aimed at assessing the impact of non-human hosts in close proximity to humans on the human biting rate of primary and secondary malaria vectors, with varying host preferences. Methods The effect of the presence of non-human hosts in close proximity to the human host on the mean catches per person per night, as a proxy for mosquito biting rate, was measured using mosquito-electrocuting traps (METs), in Sagamaganga, Kilombero Valley, Tanzania. Two experiments were designed: (1) a human versus a calf, each enclosed in a MET, and (2) a human surrounded by three calves versus a human alone, with each human volunteer enclosed individually in a MET spaced 10 m apart. Each experiment was conducted on alternate days and lasted for 36 nights per experiment. During each experiment, the positions of hosts were exchanged daily (except the human in experiment 2). All anopheline mosquitoes caught were assayed for Plasmodium sporozoites using enzyme-linked immunosorbent assay. Results A total of 20,574 mosquitoes were captured and identified during the study, of which 3608 were anophelines (84.4% primary and 15.6% secondary malaria vectors) and 17,146 were culicines. In experiment 1, the primary malaria vector, Anopheles arabiensis, along with Culex spp. demonstrated a preference for cattle, while the primary vectors, Anopheles funestus, preferred humans. In experiment 2, both primary vectors, An. arabiensis and An. funestus, as well as the secondary vector Anopheles rivolurum, demonstrated behaviours amenable to zooprophylaxis, whereas Culex spp. increased their attraction to humans in the presence of nearby cattle. All anopheline mosquitoes tested negative for sporozoites. Conclusions The findings of this study provide support for the zooprophylaxis model for malaria vectors present in the Kilombero Valley, and for the zoopotentiation model, as it pertains to the Culex spp. in the region. However, the factors regulating zooprophylaxis and zoopotentiation are complex, with different species-dependent mechanisms regulating these behaviours, that need to be considered when designing integrated vector management programmes.
Læs mere Tjek på PubMedMalaria Journal, 9.11.2023
Tilføjet 9.11.2023
Abstract Background The efficacy of chloroquine treatment for vivax malaria has been rarely evaluated due to a lack of an appropriate testing method. The objective of this study was to conduct molecular monitoring of chloroquine resistance in Plasmodium vivax strains from vivax malaria patients in Yunnan Province, focusing on the analysis of polymorphism in the P. vivax chloroquine resistance transporter protein orthologous gene (pvcrt-o). Methods In accordance with the principles of a cohort study, blood samples were collected from malaria cases diagnosed with a P. vivax mono-infection in Yunnan Province from 2020 to 2022. Segmental PCR was used to amplify the whole pvcrt-o gene in the blood samples and their products were subsequently sequenced. The sequencing data were arranged to obtain the full coding DNA sequence (CDS) as well as the gene’s promoter region sequences. The CDSs were aligned with the reference sequence (XM_001613407.1) of the P. vivax SalI isolate to identify the mutant loci. Results From a total of 375 blood samples taken from vivax malaria cases, 272 both whole gene CDSs (1272–1275 bp) and promoter DNA sequences (707 bp) of pvcrt-o gene were obtained. Among the whole CDSs, there were 7 single nucleotide polymorphic sites in which c.7 A>G was the minor allele frequency (MAF) site with 4.4% (12/272) detection rate. The mutation detection rate showed a significant decrease from 9.8% (10/102) in 2020 to 1.1% (1/92) in 2021 and 1.3% (1/78) in 2022, indicating statistical significance (χ2 = 11.256, P
Læs mere Tjek på PubMedMalaria Journal, 9.11.2023
Tilføjet 9.11.2023
Abstract Background Water resource development projects, such as dams and irrigation schemes, have a positive impact on food security and poverty reduction. However, such projects could increase prevalence of vector borne disease, such as malaria. This study investigate the impact of different agroecosystems and prevalence of malaria infection in Southwest Ethiopia. Methods Two cross-sectional surveys were conducted in the dry and wet seasons in irrigated and non-irrigated clusters of Arjo sugarcane and Gambella rice development areas of Ethiopia in 2019. A total of 4464 and 2176 study participants from 1449 households in Arjo and 546 households in Gambella enrolled in the study and blood samples were collected, respectively. All blood samples were microscopically examined and a subset of microscopy negative blood samples (n = 2244) were analysed by qPCR. Mixed effect logistic regression and generalized estimating equation were used to determine microscopic and submicroscopic malaria infection and the associated risk factors, respectively. Results Prevalence by microscopy was 2.0% (88/4464) in Arjo and 6.1% (133/2176) in Gambella. In Gambella, prevalence was significantly higher in irrigated clusters (10.4% vs 3.6%) than in non-irrigated clusters (p
Læs mere Tjek på PubMedMalaria Journal, 8.11.2023
Tilføjet 8.11.2023
Abstract The source of malaria vector populations that re-establish at the beginning of the rainy season is still unclear yet knowledge of mosquito behaviour is required to effectively institute control measures. Alternative hypotheses like aestivation, local refugia, migration between neighbouring sites, and long-distance migration (LDM) are stipulated to support mosquito persistence. This work assessed the malaria vector persistence dynamics and examined various studies done on vector survival via these hypotheses; aestivation, local refugia, local or long-distance migration across sub-Saharan Africa, explored a range of methods used, ecological parameters and highlighted the knowledge trends and gaps. The results about a particular persistence mechanism that supports the re-establishment of Anopheles gambiae, Anopheles coluzzii or Anopheles arabiensis in sub-Saharan Africa were not conclusive given that each method used had its limitations. For example, the Mark-Release-Recapture (MRR) method whose challenge is a low recapture rate that affects its accuracy, and the use of time series analysis through field collections whose challenge is the uncertainty about whether not finding mosquitoes during the dry season is a weakness of the conventional sampling methods used or because of hidden shelters. This, therefore, calls for further investigations emphasizing the use of ecological experiments under controlled conditions in the laboratory or semi-field, and genetic approaches, as they are known to complement each other. This review, therefore, unveils and assesses the uncertainties that influence the different malaria vector persistence mechanisms and provides recommendations for future studies.
Læs mere Tjek på PubMedMalaria Journal, 8.11.2023
Tilføjet 8.11.2023
Abstract Background Reducing mosquito abundance or interfering with its ability to support the parasite cycle can help to interrupt malaria in areas of significant risk of malaria transmission. Fluralaner is a safe and effective drug for veterinary use indicated for the treatment against fleas and ticks which acts as an antagonist of chloride ion channels mediated by γ-aminobutyric acid (GABA), preventing the entry of these ions into the postsynaptic neuron, leading to hyperexcitability of the postsynaptic neuron of the central nervous system of arthropods. Fluralaner demonstrated insecticidal activity against different insect species. Methods The study aimed to evaluate the effects of fluralaner on the biology, survival, and reproductive fitness of Anopheles aquasalis. The following lethal concentrations (LC) were determined for An. aquasalis: LC5 = 0.511 µM; LC25 = 1.625 µM; LC50 = 3.237 µM. Results A significant decrease (P
Læs mere Tjek på PubMedMalaria Journal, 7.11.2023
Tilføjet 7.11.2023
Abstract Background The Hubei Province in China reported its last indigenous malaria case in September 2012, but imported malaria cases, particularly those related to Plasmodium vivax and Plasmodium falciparum, threaten Hubei’s malaria-free status. This study investigated the epidemiological changes in P. vivax and P. falciparum malaria in this province to provide scientific evidence for preventing malaria resurgence. Methods The prevalence, demographic characteristics, seasonal features, and geographical distribution of malaria were assessed using surveillance data and were compared across three stages: control stage (2005–2009) and elimination stages I (2010–2014) and II (2015–2019). Results In 2005–2019, 8483 malaria cases were reported, including 5599 indigenous P. vivax cases, 275 imported P. vivax cases, 866 imported P. falciparum cases, and 1743 other cases. Imported P. falciparum cases accounted for 0.07% of all cases reported in 2005, but increased to 78.81% in 2019. Most imported P. vivax and P. falciparum malaria occurred among males, aged 21–60 years, during elimination stages I and II. The number of regions affected by imported P. falciparum and P. vivax increased markedly in Hubei from the control stage to elimination stage II. Overall, 1125 imported P. vivax and P. falciparum cases were detected from 47 other nations. Eight imported cases were detected from other provinces in China. From the control stage to elimination stage II, the number of cases of malaria imported from African countries increased, and that of cases imported from Southeast Asian countries decreased. Conclusions Although Hubei has achieved malaria elimination, it faces challenges in maintaining this status. Hence, imported malaria surveillance need to be strengthened to reduce the risk of malaria re-introduction.
Læs mere Tjek på PubMedInfection, 5.11.2023
Tilføjet 5.11.2023
Abstract Introduction Falciparum malaria remains one of the deadliest infectious diseases worldwide. In Germany, it is mainly an imported infection among travellers. Rates of coinfection are often unknown, and a clinical rationale for the beneficial use of calculated antibiotic therapy in patients with malaria and suspected coinfection is lacking. Methods We conducted an analysis of all in-patients treated with falciparum malaria at a German infectious diseases centre in vicinity to one of Europe’s major airports for 2010–2019. Logistic regression and time-to-event analysis were used to evaluate predictors for bacterial coinfection, the use of antibacterial substances, as well as their influence on clinical course. Results In total, 264 patients were included. Of those, 64% received an additional antibacterial therapy (n = 169). Twenty-nine patients (11.0%) were found to have suffered from a relevant bacterial coinfection, while only a small fraction had relevant bacteremia (n = 3, 1.4%). However, patients with severe malaria did not suffer from coinfections more frequently (p = 0.283). CRP levels were not a reliable predictor for a bacterial coinfection (OR 0.99, 95% CI 0.94–1.06, p = 0.850), while another clinical focus of infection was positively associated (OR 3.86, 95% CI 1.45–11.55, p = 0.010). Conclusion Although bacterial coinfections were rare in patients with malaria at our centre, the risk does not seem negligible. These data point rather towards individual risk assessment in respective patients than to general empiric antibiotic use.
Læs mere Tjek på PubMedInfection, 5.11.2023
Tilføjet 5.11.2023
Abstract Background Infection-associated secondary hemophagocytic lymphohistiocytosis (sHLH) is a potentially life-threatening hyperinflammatory condition caused by various infectious diseases. Malaria has rarely been described as trigger. The aim of this study is to collect data on frequency, clinical spectrum, and outcome of sHLH induced by malaria. Methods We collected case numbers on malaria and malaria-associated sHLH from specialized centers in Germany from 2015 to 2022. In addition, we conducted a literature search on published cases of malaria-associated sHLH and systematically analyzed the literature regarding clinical and diagnostic criteria. Results We obtained data from 13 centers treating 1461 malaria cases with different Plasmodium species, of which 5 patients (0.34%) also were diagnosed with sHLH. The literature search revealed detailed case reports from further 51 patients and case series comprising the description of further 24 patients with malaria-associated sHLH. Most cases (48/80; 60%) were reported from Asia. The median time interval between onset of malaria symptoms and hospital admission was 7 days. Severe complications of sHLH were documented in 36% (20/56) of patients, including two patients with multiple organ failure in our case series. Only 41% (23/56) of patients received specific treatment for sHLH, nevertheless the mortality rate (CFR) of 5% is lower compared to the CFR reported for sHLH triggered by other infectious diseases (e.g., 25% in sHLH due to EBV infection). Conclusion Malaria-associated sHLH appears to have a comparatively good prognosis but may still represent an underdiagnosed and potentially fatal complication of malaria, especially in resource-poor settings.
Læs mere Tjek på PubMedInternational Journal for Parasitology, 4.11.2023
Tilføjet 4.11.2023
Publication date: Available online 3 November 2023 Source: International Journal for Parasitology Author(s): Christa M. Seidl, Francisco C. Ferreira, Katy L. Parise, Kristina L. Paxton, Eben H. Paxton, Carter T. Atkinson, Robert C. Fleischer, Jeffrey T. Foster, A. Marm Kilpatrick
Læs mere Tjek på PubMedOlivier Paccoud, Xavier Chamillard, Eric Kendjo, Isabelle Vinatier, Laure Surgers, Denis Magne, Benjamin Wyplosz, Adéla Angoulvant, Olivier Bouchaud, Arezki Izri, Sophie Matheron, Sandrine Houzé, Marc Thellier, Alioune P. Ndour, Pierre Buffet, Eric Caumes, Stéphane Jauréguiberry, French National Reference Center for Imported Malaria Study Group
International Journal of Infectious Diseases, 4.11.2023
Tilføjet 4.11.2023
Post-artesunate delayed haemolysis (PADH) is a common non-recurring adverse effect of artesunate during severe P.falciparum malaria, which occurs after the first week of treatment in an estimated 10-30% of cases in non-immune travelers [1,2]. Reports of positive direct antiglobulin tests (DAT) in patients experiencing PADH suggest an immune-driven process [1,3]. In a systematic review, 44% of patients with PADH had a positive DAT [4]. Most prior reports focused only on patients experiencing PADH and not other patients with severe malaria.
Læs mere Tjek på PubMedMalaria Journal, 4.11.2023
Tilføjet 4.11.2023
Malaria Journal, 4.11.2023
Tilføjet 4.11.2023
Malaria Journal, 4.11.2023
Tilføjet 4.11.2023
Abstract Background The efficacy of the autodissemination of pyriproxyfen to control malaria vectors has been demonstrated under semi field environment in Tanzania. However, the information on how best communities should be engaged for its routine and large-scale adoption are lacking. This study assessed the community’s level of knowledge, perceptions, acceptability of the autodissemination of pyriproxyfen, and the perceived risks on the safety of pyriproxyfen on the environment. Methods This was a concurrent mixed methods study, comprised of a community-based survey of 400 household representatives and eight focus group discussions (FGDs). The study was conducted in two villages in Mlimba district in south-eastern Tanzania between June and August 2022. For the quantitative data analysis, descriptive statistics were applied using R software, while inductive approach was used for qualitative data analysis, using NVivo software. Results Knowledge on autodissemination of pyriproxyfen approach was found to be relatively low among both the FGD respondents and surveyed community members (36%, n = 144). Nevertheless, when it was explained to them, the envisioned community support for the autodissemination approach was relatively high (97%, n = 388). One of the major perceived benefits of the autodissemination of pyriproxyfen was the reduction of malaria-transmitting mosquitoes and associated malaria transmission. Environmental impact of pyriproxyfen on non-target organisms and health risk to children were among the major concerns. When provided with information on the safety and its utilization particularly through autodissemination approach, 93.5% (n = 374) of the survey respondents said that they would allow the PPF-contaminated pots to be placed around their homes. Similarly, FGD respondents were receptive towards the autodissemination of pyriproxyfen, but emphasized on the need for raising awareness among community members before related field trials. Conclusion This study indicates a low knowledge but high support for scaling up of the autodissemination of pyriproxyfen as a complementary tool for malaria control in rural Tanzania. The Findings of this study suggest that community sensitization activities are required to improve the community’s acceptability and trust of the approach before respective field trials.
Læs mere Tjek på PubMedMalaria Journal, 3.11.2023
Tilføjet 3.11.2023
Abstract Background The emergence of resistance to artemisinin derivatives in Southeast Asia constitutes a serious threat for other malaria endemic areas, particularly in Côte d’Ivoire. To delay this resistance, the application of the control measures recommended by the National Malaria Control Programme (NMCP) for a correct management, in the private pharmacies, is a necessity. The purpose of this study was, therefore, to assess the level of knowledge and practices of private pharmacy auxiliary in Abidjan about the management of malaria. Methods A descriptive cross-sectional study was conducted from April to November 2015. It included auxiliaries of private pharmacies in Abidjan. Data collection material was a structured an open pretested questionnaire. Data analysis was carried out using Package for Social Science (SPSS) software version 21.1. Chi square test was used to compare proportions for a significance threshold of 0.05 for the p value. Results A total, 447 auxiliaries from 163 private pharmacies were interviewed. It was noted that the auxiliaries had a good knowledge of clinical signs of uncomplicated malaria (99.1%), biological examinations (54.6% for the thick film and 40.7% for rapid diagnostic tests (RDTs) and anti-malarial drugs (99.3% for artemether + lumefantrine, AL). The strategies of vector control (long-lasting insecticide-treated mosquito nets (LLITNs, Repellent ointments, cleaning gutters, elimination of larvae breeding site and intermittent preventive treatment with sulfadoxine–pyrimethamine (IPTp-SP) in pregnant women were also known by the auxiliaries, respectively 99.8% and 77.4%. However, the malaria pathogen (25.1%) and the NMCP recommendations (e.g. use of AL or AS + AQ as first-line treatment for uncomplicated malaria and IPTp-SP in pregnant women) were not well known by the auxiliaries (28.2% and 26.9% for uncomplicated and severe malaria). Concerning the practices of the auxiliaries, 91.1% offered anti-malarial drugs to patients without a prescription and 47.3% mentioned incorrect dosages. The combination artemether + lumefantrine was the most recommended (91.3%). The delivery of anti-malarial drugs was rarely accompanied by advice on malaria prevention, neither was it carried out on the result of an RDT. Conclusion The epidemiology and the NMCP recommendations for the diagnostic and therapeutic management of malaria, are not well known to auxiliaries, which may have implications for their practices. These results show the need to sensitize and train private pharmacy auxiliaries, and also to involve them in NMCP activities.
Læs mere Tjek på PubMedPriya Venkatesan
The Lancet Microbe, 2.11.2023
Tilføjet 2.11.2023
On June 21, 2023, WHO certified Belize as malaria-free, making it the second country in central America to achieve this status after El Salvador in 2021.
Læs mere Tjek på PubMedAlexander J. BaileyChiamaka Valerie UkegbuMaria GiorgalliTanguy Rene Balthazar BessonGeorge K. ChristophidesDina VlachouaDepartment of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
Proceedings of the National Academy of Sciences, 2.11.2023
Tilføjet 2.11.2023
Proceedings of the National Academy of Sciences, Volume 120, Issue 44, October 2023.
Læs mere Tjek på PubMedPakorn Ruengket, Sittiruk Roytrakul, Daraka Tongthainan, Kanokwan Taruyanon, Bencharong Sangkharak, Paviga Limudomporn, Mongkol Pongsuchart, Chanya Udom, Wirasak Fungfuang
PLoS One Infectious Diseases, 2.11.2023
Tilføjet 2.11.2023
by Pakorn Ruengket, Sittiruk Roytrakul, Daraka Tongthainan, Kanokwan Taruyanon, Bencharong Sangkharak, Paviga Limudomporn, Mongkol Pongsuchart, Chanya Udom, Wirasak Fungfuang The number of patients infected with simian malaria is gradually increasing in many countries of Southeast Asia and South America. The most important risk factor for a zoonotic spillover event of malarial infection is mostly influenced by the interaction between humans, monkeys, and vectors. In this study, we determine the protein expression profile of a wild stump-tailed macaque (Macaca arctoides) from a total of 32 blood samples collected from Prachuap Kiri Khan Province, Thailand. The malarial parasite was analyzed using nested polymerase chain reaction (PCR) assays by dividing the samples into three groups: non-infected, mono-infected, and multiple-infected. The identification and differential proteomic expression profiles were determined using liquid chromatography with tandem mass spectrometry (LC-MS/MS) and bioinformatics tools. A total of 9,532 proteins (total proteins) were identified with the filter-based selection methods analysis, and a subset of 440 proteins were found to be different between each group. Within these proteins, the GhostKOALA functional enrichment analysis indicated that 142 important proteins were associated with either of the organismal system (28.87%), genetic information processing (23.24%), environmental information processing (16.20%), metabolism (13.38%), cellular processes (11.97%), or causing human disease (6.34%). Additionally, using interaction network analysis, nine potential reporter proteins were identified. Here, we report the first study on the protein profiles differentially expressed in the serum of wild stump-tailed macaques between non, mono, and multiple malarial infected living in a natural transmission environment. Our findings demonstrate that differentially expressed proteins implicated in host defense through lipid metabolism, involved with TGF pathway were suppressed, while those with the apoptosis pathway, such as cytokines and proinflammation signals were increased. Including the parasite’s response via induced hemolysis and disruption of myeloid cells. A greater understanding of the fundamental processes involved in a malarial infection and host response can be crucial for developing diagnostic tools, medication development, and therapies to improve the health of those affected by the disease.
Læs mere Tjek på PubMedAmerican Journal of Tropical Medicine and Hygiene, 1.11.2023
Tilføjet 1.11.2023
Journal Name: The American Journal of Tropical Medicine and Hygiene Volume: 109 Issue: 5 Pages: 1028-1035
Læs mere Tjek på PubMedAmerican Journal of Tropical Medicine and Hygiene, 1.11.2023
Tilføjet 1.11.2023
Journal Name: The American Journal of Tropical Medicine and Hygiene Volume: 109 Issue: 5 Pages: 1036-1046
Læs mere Tjek på PubMedAmerican Journal of Tropical Medicine and Hygiene, 1.11.2023
Tilføjet 1.11.2023
Journal Name: The American Journal of Tropical Medicine and Hygiene Volume: 109 Issue: 5 Pages: 1047-1056
Læs mere Tjek på PubMedAmerican Journal of Tropical Medicine and Hygiene, 1.11.2023
Tilføjet 1.11.2023
Journal Name: The American Journal of Tropical Medicine and Hygiene Volume: 109 Issue: 5 Pages: 1063-1071
Læs mere Tjek på PubMedAmerican Journal of Tropical Medicine and Hygiene, 1.11.2023
Tilføjet 1.11.2023
Journal Name: The American Journal of Tropical Medicine and Hygiene Volume: 109 Issue: 5 Pages: 1077-1080
Læs mere Tjek på PubMedMalaria Journal, 1.11.2023
Tilføjet 1.11.2023
Abstract Background Malaria vaccine, RTS, S/AS01, has demonstrated modest efficacy against malaria and holds promises for children living in areas where malaria transmission is high. This study assessed caregivers’ awareness and willingness to accept the vaccine and provided vital information for policymakers, health workers, and social mobilizers on critical areas to focus on promoting the new vaccine uptake before its arrival for use in Nigeria. Methods The study was a community-based cross-sectional survey. A multistage sampling technique was used to select four states in Northern Nigeria, where the incidence and prevalence of malaria are highest in the country and 504 caregivers of under-five children were interviewed. A semi-structured interviewer-administered questionnaire was used and data analysis was done with p-value at 0.05. Results Two hundred and three (40.3%) respondents were aware of malaria vaccine while four hundred and sixty-three (91.9%) were willing to accept the vaccine when it is introduced for use in the country. Level of education (AOR; 0.42; CI 0.23–0.78), employment status (AOR; 3.03; CI 1.82–5.03), previous experience of other childhood vaccinations (AOR; 4.87; CI 2.89–8.20), and caregivers having suffered malaria within the last one year (AOR; 1.85; CI 1.10 −3.13) significantly predicted malaria vaccine awareness. Awareness of the new malaria vaccine (AOR = 6.88; 95% CI 1.53–30.99), and previous experience of other childhood vaccinations (AOR = 6.16; 95% CI 2.54–14.94) were significant predictors of the vaccine acceptability. Conclusion Caregiver’s awareness of the new malaria vaccine was inadequate. There is a need to intensify efforts on social and behavioural communication change activities tailoring messages on the vaccine to address uptake hesitancy. Also, an intense community engagement with focus on providing information on the safety of the vaccine is encouraged.
Læs mere Tjek på PubMedMalaria Journal, 1.11.2023
Tilføjet 1.11.2023
Abstract Background Indoor residual spraying has been a key national malaria prevention and control strategy in Ethiopia. However, there is a gap in monitoring and evaluation of house-wall modification after indoor residual spraying before the end of residual lifespan. This study has determined the prevalence of house-wall modification after indoor residual spraying and identified the associated factors in Shashogo district, southern Ethiopia. Methods A community-based cross-sectional study was conducted from April to May 2022. Data were collected from 640 randomly selected households using a pre-tested questionnaire and an observational checklist. The binary logistic regression models were used to identify factors associated with house-wall modification after indoor residual spraying before the end of the potency period. Results The prevalence of house-wall modification after indoor residual spraying was found to be 30.4% (95% CI 27.4–34.2%). Educational status of could not read and write [AOR = 1.76, 95% CI (1.16, 2.68)], monthly income of more than birr 3000 [AOR = 3.27, 95% CI (1.78, 6.01)], low level of knowledge about indoor residual spraying [AOR = 3.81, 95% CI (2.39, 6.06)], lack of information within two weeks before spraying [AOR = 2.23, 95% CI (1.44, 3.46)], absence of supervision after spraying [AOR = 1.79, 95% CI (1.14, 2.81)], absence of stagnant water near house [AOR = 3.36, 95% CI (2.13, 5.39)], and thatched roof [AOR = 1.82, 95% CI (1.04, 3.16)] were factors significantly associated with house-wall modification after indoor residual spraying. Conclusion This study has revealed that the prevalence of house-wall modification after indoor residual spraying before the end of the residual lifespan in the study area was higher compared to other studies in developing countries. Therefore, special emphasis should be given to providing community education about indoor residual spraying, conducting regular supervision before and after residual spraying, enforcing some legislative strategies for modifying the house-wall before six months after spraying, and improving environmental and housing conditions.
Læs mere Tjek på PubMedCatherine Kroamah Dwumfour, Victoria Bubunyo Bam, Lydia Boampong Owusu, Collins Atta Poku, Rhoda Dewe Kpabitey, Priscilla Aboagye, Amshariatu Suntaa Ibrahim
PLoS One Infectious Diseases, 30.10.2023
Tilføjet 30.10.2023
by Catherine Kroamah Dwumfour, Victoria Bubunyo Bam, Lydia Boampong Owusu, Collins Atta Poku, Rhoda Dewe Kpabitey, Priscilla Aboagye, Amshariatu Suntaa Ibrahim Introduction Malaria in pregnancy is a global public health problem with the majority of its impact seen in sub-Saharan Africa. Pregnant women with malaria infection are at risk of adverse maternal outcomes. In Ghana, malaria in pregnancy accounts for about 17.6% of outpatient department attendance. Ashanti region is among the three regions with the highest malaria prevalence in pregnancy, particularly in the Ejisu Municipality. The study, therefore, assessed the prevalence and determinants of malaria infection among pregnant women seeking antenatal care at the Ejisu Government Hospital in Ghana. Methods A cross-sectional study design with a convenience sampling technique was used to select 140 respondents for the study. Primary data such as age and residence of respondents were collected using a questionnaire and secondary data such as gestational age and Sulphadoxine Pyrimethamine (SP) administration were collected from clients’ maternal health record booklet. Bivariate and multivariate logistic regression analysis were used to assess the association between the malaria infection and the independent variables, and a p-value of < 0.05 was considered statistically significant. Results The overall prevalence of malaria in pregnancy was 24 (17.1%). Most of the respondents had received counselling and health education 126 (90%), two or more doses of SP 95 (87.2%), Insecticide Treated Net (ITN) 99 (70.7%) and were sleeping under ITN 104 (74.3%). Multivariate logistic regression analysis showed a statistically significant association between malaria infection and sleeping under ITN (AOR = 0.05; 95% CI = 0.01–0.28, p< .001), the use of insecticide mosquito spray (AOR = 0.27; 95% CI = 0.09–0.84, p = .045) and reason for not using ITN due to the use of other preventive measures (AOR = 0.06; 95% CI = 0.01–0.61, p = .017). Conclusion There was a high prevalence of malaria infection among study respondents despite the high usage of preventive measures for malaria in this study. It is therefore crucial that stakeholders in malaria control identify effective strategies to curb malaria transmission globally.
Læs mere Tjek på PubMedMalaria Journal, 29.10.2023
Tilføjet 29.10.2023
Abstract Background Over a decade of vector control by indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) distribution on the mainland, and only LLINs on islands had a minimal impact on disease burden in Nchelenge district, northern Zambia. Anopheles funestus and Anopheles gambiae are vectors known only from the mainland. Understanding vector bionomics in the district is necessary for planning and targeting effective vector control. This study aimed to provide information on abundance, seasonality, and Plasmodium falciparum sporozoite infectivity of malaria vectors in Nchelenge, including islands. Methods Mosquitoes were collected in 192 CDC indoor light traps set in 56 households between January 2015 and January 2016. Morphological and molecular species identifications and P. falciparum circumsporoites by ELISA were performed. Mosquito counts and relative abundances from the islands and mainland were compared, and household factors associated with vector counts were determined. Results A total of 5888 anophelines were collected during the study. Of these, 5,704 were female Anopheles funestus sensu lato (s.l.) and 248 female An. gambiae s.l. The highest proportion of An. funestus (n = 4090) was from Chisenga Island and An. gambiae (n = 174) was from Kilwa Island. The highest estimated counts per trap for An. funestus s.l. were from Chisenga island, (89.9, p
Læs mere Tjek på PubMedJournal of Infectious Diseases, 29.10.2023
Tilføjet 29.10.2023
AbstractThe RTS, S/AS02A malaria vaccine is based on the Plasmodium falciparum circumsporozoite protein (PfCSP), which is O-fucosylated on the sporozoite surface. We determined whether RTS, S/AS02A-induced IgGs recognise vaccine-like non-fucosylated PfCSP better than native-like fucosylated PfCSP. Similar to previous vaccine trials, RTS, S/AS02A vaccination induced high anti-PfCSP IgG levels associated with malaria protection. IgG recognition of non-fucosylated and fucosylated PfCSP was equivalent, suggesting that PfCSP fucosylation does not affect antibody recognition.
Læs mere Tjek på PubMedMalaria Journal, 29.10.2023
Tilføjet 29.10.2023
Abstract Background This study investigates the processes regarding changing malaria treatment policies in Vietnam. Moreover, it explores the feasibility of introducing triple artemisinin-based combination therapy (TACT) in Vietnam to support the national malaria control and elimination plan. Methods Data were collected via 12 in-depth interviews with key stakeholders, combined with a review of policy documents. Results TACT is considered as a useful backup strategy in case future treatment failures with current artemisinin-based combination therapy (ACT) would occur. Moreover, TACT is also considered as a promising strategy to prevent the re-establishment of malaria. However, regulatory procedures and implementation timelines for TACT were expected to be lengthy. Therefore, strategies to engage national decision-makers, regulators, and suppliers should be initiated soon, stipulating the benefits of TACT deployment. In Vietnam, a procedure to apply for an import permit without registration that has previously been applied to the introduction of artesunate-pyronaridine was proposed to accelerate the introduction of TACT. Global-level support through the World Health Organization recommendations and prequalification were considered critical for supporting the introduction of TACT in Vietnam. Conclusions Appropriate approach strategies and early stakeholder engagement will be needed to accelerate the introduction of TACT in Vietnam.
Læs mere Tjek på PubMedBMC Infectious Diseases, 28.10.2023
Tilføjet 28.10.2023
Abstract Background The impact of metabolic resistance to insecticides on malaria transmission remains poorly characterised notably through application of entomological parameters. The lack of resistance markers has been one of the limiting factors preventing a robust assessment of such impact. To this end, the present study sought to investigate how the L119F-Gste2 metabolic gene influences entomological parameters underpinning mosquitos’ propensity to transmit Plasmodium spp. Methods Longitudinal studies were carried out in Mibellon and Elende, two different eco-climatic settings in Cameroon and mosquitoes were collected using Human Landing Catch (HLC), Centre for Disease Control Light Trap (CDC-LT) and Pyrethrum Spray Catch (PSC) technics. Plasmodium sporozoite parasites were detected by TaqMan and Nested PCR, and blood meal origin by ELISA. The allele-specific PCR (AS-PCR) method was used to genotype the L119F-GSTe2 marker and association with malaria transmission was established by comparing key transmission parameters such as the Entomological Inoculation Rate (EIR) between individuals with different L119F-GSTe2 genotypes. Results An. funestus s.l was the predominant malaria vector collected during the entomological survey in both sites (86.6% and 96.4% in Elende and Mibellon, respectively) followed by An. gambiae s.l (7.5% and 2.4%, respectively). Sporozoite infection rates were very high in both collection sites (8.7% and 11% in Elende and Mibellon, respectively). An. funestus s.s exhibited a very high entomological inoculation rate (EIR) (66 ib/h/month and 792 ib/h/year) and was responsible for 98.6% of all malaria transmission events occurring in both sites. The Human Blood Index was also high in both locations (HBI = 94%). An. funestus s.s. mosquitoes with both 119 F/F (RR) and L119F (RS) genotypes had a significantly higher transmission intensity than their susceptible L/L119 (SS) counterparts (IRR = 2.2, 95%CI (1.1–5.2), p = 0.03; IRR = 2.5, 95% CI (1.2–5.8), p = 0.01 respectively). Conclusion This study highlights the major role that An. funestus s.s plays in malaria transmission in Cameroon with an aggravation from GSTe2-based metabolic resistance.
Læs mere Tjek på PubMedClinical Infectious Diseases, 28.10.2023
Tilføjet 28.10.2023
AbstractCerebral malaria is an important cause of mortality and neurodisability in endemic regions. We show MRI features suggestive of cytotoxic and vasogenic cerebral edema followed by microhemorrhages in two adult UK cases, comparing them with an Indian cohort. Long-term follow-up images correlate ongoing changes with residual functional impairment.
Læs mere Tjek på PubMedInfection, 27.10.2023
Tilføjet 27.10.2023
Abstract Introduction Falciparum malaria remains one of the deadliest infectious diseases worldwide. In Germany, it is mainly an imported infection among travellers. Rates of coinfection are often unknown, and a clinical rationale for the beneficial use of calculated antibiotic therapy in patients with malaria and suspected coinfection is lacking. Methods We conducted an analysis of all in-patients treated with falciparum malaria at a German infectious diseases centre in vicinity to one of Europe’s major airports for 2010–2019. Logistic regression and time-to-event analysis were used to evaluate predictors for bacterial coinfection, the use of antibacterial substances, as well as their influence on clinical course. Results In total, 264 patients were included. Of those, 64% received an additional antibacterial therapy (n = 169). Twenty-nine patients (11.0%) were found to have suffered from a relevant bacterial coinfection, while only a small fraction had relevant bacteremia (n = 3, 1.4%). However, patients with severe malaria did not suffer from coinfections more frequently (p = 0.283). CRP levels were not a reliable predictor for a bacterial coinfection (OR 0.99, 95% CI 0.94–1.06, p = 0.850), while another clinical focus of infection was positively associated (OR 3.86, 95% CI 1.45–11.55, p = 0.010). Conclusion Although bacterial coinfections were rare in patients with malaria at our centre, the risk does not seem negligible. These data point rather towards individual risk assessment in respective patients than to general empiric antibiotic use.
Læs mere Tjek på PubMedMeredith Wadman
Science, 27.10.2023
Tilføjet 27.10.2023
Malaria Journal, 27.10.2023
Tilføjet 27.10.2023
Abstract Background Most data describing severe malaria (SM) in sub-Saharan Africa (SSA) are from research settings outside disease endemic areas. Using routinely collected data from Apac District Hospital, this study aimed at determining the burden and clinical spectrum of severe malaria. Methods This was a retrospective study that reviewed all paediatric admission records for malaria in the 24 months period from Jan 2019 to Dec 2020 at Apac District Hospital. Data on children aged 60 days to 12 years who at admission tested positive for malaria and fulfilled the World Health Organization clinical criteria for surveillance of severe malaria were abstracted using a customized proforma designed to capture variables on social demographic, clinical presentation, treatment, and outcomes. In addition, the tool included laboratory variables for complete blood counts, haemoglobin, and glucose levels. Data were analysed using STATA V15.0. The study had ethical approval from Mbale Regional Referral Hospital REC, Approval No. MRRH-REC 053/2019. Results A total of 5631 admission records were retrieved for this study period. Of these, 3649 (64.8%) were malaria admissions and 3422/3649 were children below 12years, with only 1864 (54.5%) of children having complete data. Of the 1864 children, 745 (40.0%) fulfilled the severe malaria inclusion criteria. Of the 745 children, 51.4% (n = 381) were males. The median age at admission was 31 months (IQR = 17–60). The most common clinical presentations among children with severe malaria were fever 722 (97.3%), cough 478 (64.2%), and difficulty in breathing 122 (17.9%). The median length of hospital stay was 2 (IQR; 2–4) days and 133 (17.9%) had prolonged hospital stay (> 4 days). Factors independently associated with prolonged hospital stay were, presenting with difficulty in breathing, aOR 1.83 (95% CI 1.02–3.27, P = 0.042) and prostration aOR 8.47 (95% CI 1.94–36.99, P = 0.004). A majority of admitted children, 735 (98.7%) survived, while 10 (1.3%) died of SM. Conclusion A high proportion (40.0%) of malaria admissions were due to SM. Prolonged Hospital stay was associated with prostration and difficulty in breathing. Overall mortality was low, 1.3% compared to mortality in the previously reported series. This study was able to use routinely collected data to describe the burden and clinical spectrum of SM. Improvement in the quality of data from such settings would improve disease descriptions for policy, monitoring of epidemics, response to interventions and to inform research.
Læs mere Tjek på PubMedTadele Emiru, Dejene Getachew, Maxwell Murphy, Luigi Sedda, Legesse Alamerie Ejigu, Mikiyas Gebremichael Bulto, Isabel Byrne, Mulugeta Demisse, Melat Abdo, Wakweya Chali, Aaron Elliott, Eric Neubauer Vickers, Andrés Aranda-Díaz, Lina Alemayehu, Sinknesh W. Behaksera, Gutema Jebessa, Hunduma Dinka, Tizita Tsegaye, Hiwot Teka, Sheleme Chibsa, Peter Mumba, Samuel Girma, Jimee Hwang, Melissa Yoshimizu, Alice Sutcliffe, Hiwot Solomon Taffese, Gudissa Aseffa Bayissa, Sarah Zohdy, Jon Eric Tongren, Chris Drakeley, Bryan Greenhouse, Teun Bousema, Fitsum G. Tadesse
Nature, 26.10.2023
Tilføjet 26.10.2023
Chisambo Mwaba, Sody Munsaka, Bruce Bvulani, David Mwakazanga, Brian Chanda Chiluba, Kaiser Fitzwanga, Evans Mpabalwani
PLoS One Infectious Diseases, 26.10.2023
Tilføjet 26.10.2023
by Chisambo Mwaba, Sody Munsaka, Bruce Bvulani, David Mwakazanga, Brian Chanda Chiluba, Kaiser Fitzwanga, Evans Mpabalwani Background Whilst malaria is a prominent aetiology associated with acute kidney injury (AKI) in many parts of Africa, a shift in the traditional AKI aetiologies has been witnessed in sections of the continent. Additionally, limited access to dialysis worsens patient outcomes in these low-resource settings. This retrospective cross-sectional study aimed to determine the associated aetiologies, predictors of need for dialysis and malaria-associated AKI (MAKI), and outcomes of AKI and dialysis among children evaluated by the renal service in Lusaka, Zambia. Methods The study sampled all children aged 16 years or below, diagnosed with AKI between 2017 and 2021, by the renal unit at the University Teaching Hospitals- Children’s Hospital (UTH-CH), and retrospectively abstracted their records for exposures and outcomes. AKI was defined using the Kidney Disease Improving Global Outcomes (KDIGO) 2012 criteria. Frequency and percentage distributions were used to describe the occurrence of AKI aetiologies and treatment outcomes. Predictors of the need for dialysis, MAKI, and poor treatment outcome were identified by using multivariable logistic regression models. Results A total of 126 children diagnosed with AKI were included in this study. Malaria was the most frequent aetiology of AKI(61.1% (77/126, 95% Confidence Interval (CI): 52.0%-69.7%)). Of the 126 children with AKI, 74.6% (94) underwent dialysis. Predictors of the need for dialysis were oliguria (p = 0.0024; Odds ratio (OR) = 7.5, 95% CI: 2.1–27.7) and anuria (p = 0.0211; OR = 6.4, 95% CI = 1.3, 30.7). A fifth (18.3%, 23/126) of the children developed chronic kidney disease (CKD), 5.6% (7/126) died and, a year later, 77% (97/126) were lost to follow-up. Conclusion At UTH-CH, malaria is the most frequent aetiology among children with AKI undergoing dialysis and children from low-medium malaria incidence areas are at risk; a considerable proportion of children with AKI need dialysis and Tenchoff catheter use in AKI is advocated.
Læs mere Tjek på PubMedMalaria Journal, 26.10.2023
Tilføjet 26.10.2023
Abstract Background Indoor residual spraying (IRS) is a common vector control strategy in countries with high malaria burden. Historically, social norms have prevented women from working in IRS programmes. The Bioko Island Malaria Elimination Project has actively sought to reduce gender inequality in malaria control operations for many years by promoting women’s participation in IRS. Methods This study investigated the progress of female engagement and compared spray productivity by gender from 2010 to 2021, using inferential tests and multivariable regression. Spray productivity was measured by rooms sprayed by spray operator per day (RSOD), houses sprayed by spray operator per day (HSOD), and the daily productivity ratio (DPR), defined as the ratio of RSOD to HSOD, which standardized productivity by house size. Results The percentage of women participating in IRS has increased over time. The difference in DPR comparing male and female spray operators was only statistically significant (p
Læs mere Tjek på PubMedInfection, 25.10.2023
Tilføjet 25.10.2023
Abstract Background Infection-associated secondary hemophagocytic lymphohistiocytosis (sHLH) is a potentially life-threatening hyperinflammatory condition caused by various infectious diseases. Malaria has rarely been described as trigger. The aim of this study is to collect data on frequency, clinical spectrum, and outcome of sHLH induced by malaria. Methods We collected case numbers on malaria and malaria-associated sHLH from specialized centers in Germany from 2015 to 2022. In addition, we conducted a literature search on published cases of malaria-associated sHLH and systematically analyzed the literature regarding clinical and diagnostic criteria. Results We obtained data from 13 centers treating 1461 malaria cases with different Plasmodium species, of which 5 patients (0.34%) also were diagnosed with sHLH. The literature search revealed detailed case reports from further 51 patients and case series comprising the description of further 24 patients with malaria-associated sHLH. Most cases (48/80; 60%) were reported from Asia. The median time interval between onset of malaria symptoms and hospital admission was 7 days. Severe complications of sHLH were documented in 36% (20/56) of patients, including two patients with multiple organ failure in our case series. Only 41% (23/56) of patients received specific treatment for sHLH, nevertheless the mortality rate (CFR) of 5% is lower compared to the CFR reported for sHLH triggered by other infectious diseases (e.g., 25% in sHLH due to EBV infection). Conclusion Malaria-associated sHLH appears to have a comparatively good prognosis but may still represent an underdiagnosed and potentially fatal complication of malaria, especially in resource-poor settings.
Læs mere Tjek på PubMedBMC Infectious Diseases, 25.10.2023
Tilføjet 25.10.2023
Abstract Background RTS,S/AS01 has been recommended by WHO for widespread implementation in medium to high malaria transmission settings. Previous analyses have noted lower vaccine efficacies in higher transmission settings, possibly due to the more rapid development of naturally acquired immunity in the control group. Methods To investigate a reduced immune response to vaccination as a potential mechanism behind lower efficacy in high transmission areas, we examine initial vaccine antibody (anti-CSP IgG) response and vaccine efficacy against the first case of malaria (to exclude the effect of naturally acquired immunity) using data from three study areas (Kintampo, Ghana; Lilongwe, Malawi; Lambaréné, Gabon) from the 2009–2014 phase III trial (NCT00866619). Our key exposures are parasitemia during the vaccination series and background malaria incidence. We calculate vaccine efficacy (one minus hazard ratio) using a cox-proportional hazards model and allowing for the time-varying effect of RTS,S/AS01. Results We find that antibody responses to the primary three-dose vaccination series were higher in Ghana than in Malawi and Gabon, but that neither antibody levels nor vaccine efficacy against the first case of malaria varied by background incidence or parasitemia during the primary vaccination series. Conclusions We find that vaccine efficacy is unrelated to infections during vaccination. Contributing to a conflicting literature, our results suggest that vaccine efficacy is also unrelated to infections before vaccination, meaning that control-group immunity is likely a major reason for lower efficacy in high transmission settings, not reduced immune responses to RTS,S/AS01. This may be reassuring for implementation in high transmission settings, though further studies are needed.
Læs mere Tjek på PubMedBMC Infectious Diseases, 25.10.2023
Tilføjet 25.10.2023
Abstract Background RTS,S/AS01 has been recommended by WHO for widespread implementation in medium to high malaria transmission settings. Previous analyses have noted lower vaccine efficacies in higher transmission settings, possibly due to the more rapid development of naturally acquired immunity in the control group. Methods To investigate a reduced immune response to vaccination as a potential mechanism behind lower efficacy in high transmission areas, we examine initial vaccine antibody (anti-CSP IgG) response and vaccine efficacy against the first case of malaria (to exclude the effect of naturally acquired immunity) using data from three study areas (Kintampo, Ghana; Lilongwe, Malawi; Lambaréné, Gabon) from the 2009–2014 phase III trial (NCT00866619). Our key exposures are parasitemia during the vaccination series and background malaria incidence. We calculate vaccine efficacy (one minus hazard ratio) using a cox-proportional hazards model and allowing for the time-varying effect of RTS,S/AS01. Results We find that antibody responses to the primary three-dose vaccination series were higher in Ghana than in Malawi and Gabon, but that neither antibody levels nor vaccine efficacy against the first case of malaria varied by background incidence or parasitemia during the primary vaccination series. Conclusions We find that vaccine efficacy is unrelated to infections during vaccination. Contributing to a conflicting literature, our results suggest that vaccine efficacy is also unrelated to infections before vaccination, meaning that control-group immunity is likely a major reason for lower efficacy in high transmission settings, not reduced immune responses to RTS,S/AS01. This may be reassuring for implementation in high transmission settings, though further studies are needed.
Læs mere Tjek på PubMedStephen P. Mwangungulu, Deus Dorothea, Zakaria R. Ngereja, Emmanuel W. Kaindoa
PLoS One Infectious Diseases, 24.10.2023
Tilføjet 24.10.2023
by Stephen P. Mwangungulu, Deus Dorothea, Zakaria R. Ngereja, Emmanuel W. Kaindoa Background Malaria continues to pose a major public health challenge in tropical regions. Despite significant efforts to control malaria in Tanzania, there are still residual transmission cases. Unfortunately, little is known about where these residual malaria transmission cases occur and how they spread. In Tanzania for example, the transmission is heterogeneously distributed. In order to effectively control and prevent the spread of malaria, it is essential to understand the spatial distribution and transmission patterns of the disease. This study seeks to predict areas that are at high risk of malaria transmission so that intervention measures can be developed to accelerate malaria elimination efforts. Methods This study employs a geospatial based model to predict and map out malaria risk area in Kilombero Valley. Environmental factors related to malaria transmission were considered and assigned valuable weights in the Analytic Hierarchy Process (AHP), an online system using a pairwise comparison technique. The malaria hazard map was generated by a weighted overlay of the altitude, slope, curvature, aspect, rainfall distribution, and distance to streams in Geographic Information Systems (GIS). Finally, the risk map was created by overlaying components of malaria risk including hazards, elements at risk, and vulnerability. Results The study demonstrates that the majority of the study area falls under moderate risk level (61%), followed by the low risk level (31%), while the high malaria risk area covers a small area, which occupies only 8% of the total area. Conclusion The findings of this study are crucial for developing spatially targeted interventions against malaria transmission in residual transmission settings. Predicted areas prone to malaria risk provide information that will inform decision-makers and policymakers for proper planning, monitoring, and deployment of interventions.
Læs mere Tjek på PubMedMalaria Journal, 23.10.2023
Tilføjet 23.10.2023
Abstract Background Low peripheral parasitaemia caused by sequestration of Plasmodium falciparum in the placenta hampers the diagnosis of malaria in pregnant women, leading to microscopy or conventional rapid diagnostic tests (RDTs) false-negative results. Although mainly asymptomatic, maternal malaria remains harmful to pregnant women and their offspring in endemic settings and must be adequately diagnosed. Ultra-sensitive RDTs (uRDTs) are thought to be more sensitive than RDTs, and their diagnostic performance was assessed in the current study in pregnant women living in Kinshasa, a stable malaria transmission area in the Democratic Republic of the Congo. Methods To assess and compare the diagnostic performances of both RDTs and uRDTs, 497 peripheral blood samples were tested using microscopy and quantitative polymerase chain reaction (qPCR) as the index and the reference tests, respectively. The agreement between the different diagnostic tests assessed was estimated by Cohen\'s Kappa test. Results The median parasite density by qPCR was 292 p/μL of blood [IQR (49.7–1137)]. Using qPCR as the reference diagnostic test, the sensitivities of microscopy, RDT and uRDT were respectively [55.7% (95% CI 47.6–63.6)], [81.7% (95%CI 74.7–87.3)] and [88% (95% CI 81.9–92.6)]. The specificities of the tests were calculated at 98.5% (95% CI 96.6–99.5), 95.2% (95% CI 92.5–97.2) and 94.4% (95% CI 91.4–96.6) for microscopy, RDT and uRDT, respectively. The agreement between qPCR and uRDT was almost perfect (Kappa = 0.82). For parasite density (qPCR) below 100 p/µL, the sensitivity of RDT was 62% (95% CI 47.1–75.3) compared to 68% (95% CI 53.3–80.4) for uRDT. Between 100 and 200 p/µL, the sensitivity of RDT was higher, but still lower compared to uRDT: 89.4% (95% CI 66.8–98.7) for RDT versus 100% (95% CI 82.3–100) for uRDT. In both cases, microscopy was lower, with 20% (95% CI 10–33.7) and 47.3% (95% CI 24.4–71.1) respectively. Conclusions uRDT has the potential to improve malaria management in pregnant women as it has been found to be slightly more sensitive than RDT in the detection of malaria in pregnant women but the difference was not significant. Microscopy has a more limited value for the diagnosis of malaria during the pregnancy, because of its lower sensitivity.
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