James W. Rudge, Nui Inthalaphone, Rebecca Pavlicek, Phimpha Paboriboune, Bruno Flaissier, Chou Monidarin, Nicolas Steenkeste, Viengmon Davong, Manivanh Vongsouvath, K. A. Bonath, Melinda Messaoudi, Mitra Saadatian-Elahi, Paul Newton, Hubert Endtz, David Dance, Glaucia Paranhos Baccala, Valentina Sanchez Picot

by James W. Rudge, Nui Inthalaphone, Rebecca Pavlicek, Phimpha Paboriboune, Bruno Flaissier, Chou Monidarin, Nicolas Steenkeste, Viengmon Davong, Manivanh Vongsouvath, K. A. Bonath, Melinda Messaoudi, Mitra Saadatian-Elahi, Paul Newton, Hubert Endtz, David Dance, Glaucia Paranhos Baccala, Valentina Sanchez Picot Respiratory diseases are a major contributor to morbidity and mortality in many tropical countries, including Lao PDR. However, little has been published regarding viral or bacterial pathogens that can contribute to influenza-like illness (ILI) in a community setting. We report on the results of a community-based surveillance that prospectively monitored the incidence of ILI and its causative pathogens in Vientiane capital in Lao PDR. A cohort of 995 households, including 4885 study participants, were followed-up between May 2015 and May 2016. Nasopharyngeal swabs, throat swabs, and sputum specimens were collected from ILI cases identified through active case-finding. Real-Time PCR was used to test nasopharyngeal swabs for 21 respiratory pathogens, while throat and sputum samples were subjected to bacterial culture. Generalized linear mixed models were used to assess potential risk factors for associations with ILI. In total, 548 episodes of ILI were reported among 476 (9.7%) of the study participants and 330 (33.2%) of the study households. The adjusted estimated incidence of ILI within the study area was 10.7 (95%CI: 9.4–11.9) episodes per 100 person-years. ILI was significantly associated with age group (p

Anne-Flore Plane, Pierre-Emmanuel Marsan, Damien du Cheyron, Xavier Valette

A 58-year-old man was hospitalised in our intensive care unit for severe, acute respiratory distress syndrome caused by an influenza virus infection. After 31 days, he was gradually weaned off mechanical ventilation. However, on the day after extubation, he had to be reintubated because of further respiratory distress. Emergency intubation was performed after rapid sequence induction using the short-acting anaesthetic agent etomidate, intravenously, at a dose of 0·3 mg/kg, and the muscle relaxant succinylcholine, intravenously, at a dose of 1 mg/kg.

Geraint B Rogers

Acute lower respiratory tract infections (LRTIs) are a major source of early life morbidity and the principal infectious cause of infant mortality.1 A growing body of research suggests that the microbiome of the upper respiratory tract substantially influences the incidence and severity of LRTIs. The nasopharyngeal mucosa is the first line of defence against airborne pathogens. In addition to the mechanisms of host innate immunity, the commensal microbiota suppresses the expansion of populations of opportunistic pathogens that are common in the nasopharynx—including Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus—through a combination of competitive exclusion, suppression of virulence through direct inter-species interaction, and regulation of local immunity.

Lindsey BB, Armitage EP, Kampmann B, de Silva TI. The efficacy, effectiveness, and immunogenicity of influenza vaccines in Africa: a systematic review. Lancet Infect Dis 2019; 19: e110–19—Figure 2 and the panel have been corrected. These corrections have been made to the online version as of April 16, 2019.

Colin R Simpson, Dan Beever, Kirsty Challen, Daniela De Angelis, Ellen Fragaszy, Steve Goodacre, Andrew Hayward, Wei Shen Lim, G James Rubin, Malcolm G Semple, Marian Knight, NIHR hibernated influenza studies collaborative group

The 2009 influenza A H1N1 pandemic was responsible for considerable global morbidity and mortality. In 2009, several research studies in the UK were rapidly funded and activated for clinical and public health actions. However, some studies were too late for their results to have an early and substantial effect on clinical care, because of the time required to call for research proposals, assess, fund, and set up the projects. In recognition of these inherent delays, a portfolio of projects was funded by the National Institute for Health Research in 2012.

Julien Coussement, David Lebeaux, Najla El Bizri, Vincent Claes, Michel Kohnen, Deborah Steensels, Isabelle Étienne, Hélène Salord, Emmanuelle Bergeron, Veronica Rodriguez-Nava

by Julien Coussement, David Lebeaux, Najla El Bizri, Vincent Claes, Michel Kohnen, Deborah Steensels, Isabelle Étienne, Hélène Salord, Emmanuelle Bergeron, Veronica Rodriguez-Nava Background Transplant recipients are at risk of pulmonary nocardiosis, a life-threatening opportunistic infection caused by Nocardia species. Given the limitations of conventional diagnostic techniques (i.e., microscopy and culture), a polymerase chain reaction (PCR)-based assay was developed to detect Nocardia spp. on clinical samples. While this test is increasingly being used by transplant physicians, its performance characteristics are not well documented. We evaluated the performance characteristics of this test on bronchoalveolar lavage (BAL) fluid samples from lung transplant recipients (LTRs). Methods We prospectively included all BAL samples from LTRs undergoing bronchoscopy at our institution between December 2016 and June 2017 (either surveillance or clinically-indicated bronchoscopies). Presence of microbial pathogens was assessed using techniques available locally (including microscopy and 10-day culture for Nocardia). BAL samples were also sent to the French Nocardiosis Observatory (Lyon, France) for the Nocardia PCR-based assay. Transplant physicians and patients were blinded to the Nocardia PCR results. Results We included 29 BAL samples from 21 patients (18 surveillance and 11 clinically-indicated bronchoscopies). Nocardiosis was not diagnosed in any of these patients by conventional techniques. However, Nocardia PCR was positive in five BAL samples from five of the patients (24%, 95% confidence interval: 11–45%); four were asymptomatic and undergoing surveillance bronchoscopy, and one was symptomatic and was later diagnosed with influenza virus infection. None of the five PCR-positive patients died or were diagnosed with nocardiosis during the median follow-up of 21 months after the index bronchoscopy (range: 20–23 months). Conclusions In this prospective study, Nocardia PCR was positive on BAL fluid from one fourth of the LTRs. Nocardia PCR-based assays should be used with caution on respiratory samples from LTRs because of the possible detection of airway colonization using this technique. Larger studies are required to determine the usefulness of the Nocardia PCR-based assay in transplant recipients.…

Tatiana Schäffer Gregianini, Claudete Farina Seadi, Luiz Domingos Zavarize Neto, Letícia Garay Martins, Guilherme Cerutti Muller, Selir Maria Straliotto, Ana Beatriz Gorini da Veiga

Abstract Problem Human parainfluenza virus (hPIV) is an important pathogen in respiratory infections, however the health burden of hPIV is underestimated. This study describes the infections by hPIV1‐3 in Rio Grande do Sul, Brazil, from 1990 to 2017, providing data of the frequency and seasonality of cases and associated clinical symptoms. Method of study Nasopharyngeal samples of patients with respiratory infection were collected, clinical data were analyzed, and immunofluorescence was used to detect hPIV. Results Respiratory viruses were detected in 33.63% of respiratory infections. In a total of 11 606 cases of viral respiratory infection, 781 were positive for hPIV; hPIV prevalence ranged from 2.14% to 27% of viral respiratory infections. hPIV1 circulates mainly during fall; hPIV3 circulation, in turn, starts in fall and peaks during spring; and cases of hPIV2 are reported along the year, with peaks in fall and early spring. The most affected age group was children, with hPIV prevalence of 74.23% in patients for less than 1 year. A higher proportion of girls were infected than boys, however, no difference by sex was observed considering all age groups. The most frequent type was hPIV3, especially in hospitalized patients. Both hPIV1 and 3 were associated with dyspnea, while hPIV2 caused mild symptoms mainly in nonhospitalized patients. Nineteen fatalities occurred, 89.5% of them associated with risk factors (prematurity; chronic diseases; age, 60 years). Conclusion hPIV causes a high number of respiratory infections, leading to hospitalization especially in children; epidemiological and surveillance studies are important for the control and management of respiratory infections.

Rowe, H. M., Mann, B., Iverson, A., Poole, A., Tuomanen, E., Rosch, J. W.

Acute otitis media is one of the most common childhood infections worldwide. Currently licensed vaccines against the common otopathogen, Streptococcus pneumoniae, target the bacterial capsular polysaccharide and confer no protection against non-encapsulated strains or capsular types outside of vaccine coverage. Mucosal infections such as acute otitis media remain prevalent, even those caused by vaccine-covered serotypes. Here we report that a protein-based vaccine, a fusion construct of epitopes of CbpA to pneumolysin toxoid, confers effective protection against pneumococcal acute otitis media for non-PCV-13 serotypes and enhances protection for PCV-13 serotypes when co-administered with PCV-13. Having crossreactive epitopes, the fusion protein also induces potent antibody responses against non-typeable Haemophilus influenzae and S. pneumoniae, engendering protection against acute otitis media caused by emerging unencapsulated otopathogens. These data suggest that augmenting capsule-based vaccination with conserved, cross-reactive protein-based vaccines may broaden and enhance protection against acute otitis media.…

Karawita, Anjana C.; Tong, Marcus Z.W.; Short, Kirsty R.

Purpose of review A delicate balance exists between a protective and detrimental immune response to an invading viral pathogen. Here, we review the latest advancements in our understanding of immunity and immunopathology during H7N9 influenza A virus (IAV) infections and its relevance to disease management and diagnosis. Recent findings Recent studies have highlighted the role of specific leukocytes in the pathogenesis of H7N9 IAV infections and potential diagnostic role that host cytokine profiles can play in forecasting disease severity. Furthermore, alterations in diet have emerged as a possible preventive measure for severe IAV infections. Summary The recent emergence and continued evolution of H7N9 IAVs have emphasized the threat that these avian viruses pose to human health. Understanding the role of the host immune response in both disease protection and pathogenesis is an essential first step in the creation of novel therapeutic and preventive measures for H7N9 IAV infections. Correspondence to Kirsty R. Short, Brisbane, Qld Australia. Tel: +61 7 3365 3732; e-mail: k.short@uq.edu.au Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Han A, Czajkowski L, Donaldson A, et al.

AbstractBackgroundThe development of vaccines and therapeutics have relied on healthy volunteer influenza challenge studies. A validated human infection model with wild-type A(H1N1)pdm09 was reported previously.ObjectiveTo characterize a wild-type Influenza A/Bethesda/MM1/H3N2 challenge virus in healthy volunteers.MethodsParticipants received a single dose of a cell-based, reverse-genetics, GMP-produced wild-type influenza A/H3N2/2011 virus intranasally and were isolated at the NIH Clinical Center for > 9 days. Dose escalation was performed from 104 to 107 TCID50. Viral shedding and clinical disease were evaluated daily.ResultsOf 37 participants challenged, 16 (43%) had viral shedding and 27 (73%) developed symptoms with 12 participants (32%) experiencing mild to moderate influenza disease (MMID) defined as shedding and symptoms. Only participants receiving the 106 and 107 TCID50 doses experienced MMID at 44% and 40%, respectively. Symptom severity peaked on day 3 while most viral shedding occurred 1-2 days after challenge. Only 10 (29%) participants had > fourfold rise in hemagglutinin inhibition (HAI) antibody titer after challenge.ConclusionsThe A/Bethesda/MM1/H3N2 challenge virus safely induced MMID in healthy volunteers, but caused less MMID than the A(H1N1)pdm09 challenge virus even at the highest dose. There was less detection of shedding though the incidence of symptoms was similar to A(H1N1)pdm09. Fewer serum anti-HA antibody responses with less MMID indicate that preexisting immunity factors other than anti-HA antibody may limit shedding in healthy volunteers. This A/Bethesda/MM1/H3N2 challenge virus can be utilized in future studies to further explore pathogenesis and immunity and to evaluate vaccine candidates.

Abstract Background Detecting the onset of influenza epidemic is important for epidemiological surveillance and for investigating the factors driving spatiotemporal transmission patterns. Most approaches define the epidemic onset based on thresholds, which use subjective criteria and are specific to individual surveillance systems. Methods We applied the empirical threshold method (ETM), together with two non-thresholding methods, including the maximum curvature method (MCM) that we proposed and the segmented regression method (SRM), to determine onsets of influenza epidemics in each prefecture of Japan, using sentinel surveillance data of influenza-like illness (ILI) from 2012/2013 through 2017/2018. Performance of the MCM and SRM was evaluated, in terms of epidemic onset, end, and duration, with those derived from the ETM using the nationwide epidemic onset indicator of 1.0 ILI case per sentinel per week. Results The MCM and SRM yielded complete estimates for each of Japan’s 47 prefectures. In contrast, ETM estimates for Kagoshima during 2012/2013 and for Okinawa during all six influenza seasons, except 2013/2014, were invalid. The MCM showed better agreement in all estimates with the ETM than the SRM (R2 = 0.82, p 

Jia W, Wen X, Xie S, et al.

To the Editor—In their recent article, Ning et al [1] analyzed antigenic drift of influenza A(H7N9) virus haemagglutinin (HA). Their findings showed that some key mutations affecting antigenicity may have appeared in H7N9 in the past 5 years. To further evaluate the changes of antigenicity of H7N9, we studied the antigenicity and molecular characteristics of a new H7N9 virus isolated from poultry. We found a novel antigenic drift, which is different from previous findings. To our knowledge, this is the first antigenic change found after the implementation of China’s immunization policy in poultry.

Jianjian Wei, Jie Zhou, Yakun Liu, Jie Wu, Tao Jin, Yuguo Li, Hui-Ling Yen

by Jianjian Wei, Jie Zhou, Yakun Liu, Jie Wu, Tao Jin, Yuguo Li, Hui-Ling Yen Infectious virus-laden aerosols generated during poultry processing may mediate airborne transmissions of avian influenza at live poultry markets. To develop effective control measures to reduce aerosol dispersion, we characterised the aerosol flow pattern of the mechanical defeatherers, a major source of aerosol dispersion during poultry processing at live poultry markets in China. Mechanical defeatherers create a strong air circulation during operation with inflow and outflow velocities over 1 m/s. A partial lid was designed to suppress the outflow and reduce aerosol dispersion. Computational fluid dynamics simulations confirmed that the partial lid prototype reduced the aerosol escape rate by over 65%. To validate the effectiveness of the partial lid in reducing aerosol dispersion, a field study was conducted at a retail poultry shop in Guangzhou and the concentrations of influenza viral RNA and avian 18S rRNA dispersed in air were monitored during poultry processing, with and without the use of the partial lid. At the breathing zone of the poultry worker, the use of the partial lid effectively suppressed the upward airflow and reduced the concentration of avian 18S rRNA in the air by 57%. The economic and practical partial lid can be easily implemented to reduce generation of influenza virus-laden aerosols at live poultry markets.

Ysebaert, C., Denoël, P., Weynants, V., Bakaletz, L. O., Novotny, L. A., Godfroid, F., Hermand, P.

PE-PilA is a fusion protein composed of immunologically relevant parts of protein E (PE) and the majority subunit of the type IV pilus (PilA), two major antigens of nontypeable Haemophilus influenzae (NTHi). Here we report on the preclinical evaluation of PE-PilA as vaccine antigen. The immunogenic potential of PE and PilA within the fusion was compared with that of isolated PE and PilA antigens.When injected intramuscularly in mice, the immunogenicity of PE within the fusion was equivalent to that of isolated PE, except when formulated with alum. In contrast, in our murine models PilA was consistently found more immunogenic as a sub-entity of the PE-PilA fusion protein than when injected as an isolated antigen. Anti-PE antibodies following immunization with PE-PilA, demonstrated the same capacity to inhibit the binding of PE to vitronectin than those induced after PE immunization. Likewise, PE-PilA-induced anti-PilA antibodies inhibited the formation of NTHi biofilms and disrupted established biofilms in vitro. These experiments support the immunogenic equivalence between fused PE-PilA and isolated PE and PilA, respectively. Further, the potential of PE-PilA immunization against NTHi-induced disease was evaluated. After intranasal NTHi challenge, colonisation of the murine nasopharynx significantly dropped in animals formerly immunized with PE-PilA, and in chinchillas, signs of otitis media were significantly reduced in animals that have received anti-PE-PilA antibodies.Taken together, our data support the use of PE-PilA as an NTHi vaccine antigen.…

Najat Bdeir, Prerna Arora, Sabine Gärtner, Markus Hoffmann, Udo Reichl, Stefan Pöhlmann, Michael Winkler

by Najat Bdeir, Prerna Arora, Sabine Gärtner, Markus Hoffmann, Udo Reichl, Stefan Pöhlmann, Michael Winkler Influenza A virus (IAV) infection poses a serious health threat and novel antiviral strategies are needed. Defective interfering particles (DIPs) can be generated in IAV infected cells due to errors of the viral polymerase and may suppress spread of wild type (wt) virus. The antiviral activity of DIPs is exerted by a DI genomic RNA segment that usually contains a large deletion and suppresses amplification of wt segments, potentially by competing for cellular and viral resources. DI-244 is a naturally occurring prototypic segment 1-derived DI RNA in which most of the PB2 open reading frame has been deleted and which is currently developed for antiviral therapy. At present, coinfection with wt virus is required for production of DI-244 particles which raises concerns regarding biosafety and may complicate interpretation of research results. Here, we show that cocultures of 293T and MDCK cell lines stably expressing codon optimized PB2 allow production of DI-244 particles solely from plasmids and in the absence of helper virus. Moreover, we demonstrate that infectivity of these particles can be quantified using MDCK-PB2 cells. Finally, we report that the DI-244 particles produced in this novel system exert potent antiviral activity against H1N1 and H3N2 IAV but not against the unrelated vesicular stomatitis virus. This is the first report of DIP production in the absence of infectious IAV and may spur efforts to develop DIPs for antiviral therapy.

Sarah F. Andrews, Michael J. Chambers, Chaim A. Schramm, Jason Plyler, Julie E. Raab, Masaru Kanekiyo, Rebecca A. Gillespie, Amy Ransier, Sam Darko, Jianfei Hu, Xuejun Chen, Hadi M. Yassine, Jeffrey C. Boyington, Michelle C. Crank, Grace L. Chen, Emily Coates, John R. Mascola, Daniel C. Douek, Barney S. Graham, Julie E. Ledgerwood, Adrian B. McDermott

Influenza vaccination occurs in the context of pre-existing immunity. Andrews et al. compare the pre-existing memory IgG B cell response recognizing conserved epitopes on influenza hemagglutinin with the newly generated response to strain-specific epitopes upon H7N9 vaccination. The differences in magnitude, phenotype, and affinity maturation between the two responses highlight the challenges in achieving long-lasting, broad protection against an ever-evolving virus.

Phillips, Z. N., Brizuela, C., Jennison, A. V., Staples, M., Grimwood, K., Seib, K. L., Jennings, M. P., Atack, J. M.

Non-typeable Haemophilus influenzae (NTHi) is a major human pathogen, responsible for several acute and chronic infections of the respiratory tract. The incidence of invasive infections caused by NTHi is increasing world-wide. NTHi is able to colonise the nasopharynx asymptomatically, and the exact change(s) responsible for transition from benign carriage to overt disease are not understood. We have previously reported that phase-variation (the rapid and reversible ON-OFF switching of gene expression) of particular lipooligosaccharide (LOS) glycosyltransferases occurs during transition from colonising the nasopharynx to invading the middle ear. Variation in the structure of the LOS is dependent on the ON/OFF expression status of each of the glycosyltransferases responsible for LOS biosynthesis. In this study we surveyed a collection of invasive NTHi isolates for ON/OFF expression status of seven phase-variable LOS glycosyltransferases. We report that the expression state of the LOS biosynthetic genes oafA ON and lic2A OFF show a correlation with invasive NTHi isolates. We hypothesise that these gene expression changes contribute to the invasive potential of NTHi. OafA expression, which is responsible for the addition of an O-acetyl group onto the LOS, has been shown to impart a phenotype of increased serum resistance, and may serve as a marker for invasive NTHi.…

Laura K. Borkenhagen, Mo D. Salman, Mai-Juan Ma, Gregory C. Gray

Hadara L. Norowitz, Timothy Morello, Hadassah M. Kupfer, Stephan A. Kohlhoff, Tamar A. Smith-Norowitz

by Hadara L. Norowitz, Timothy Morello, Hadassah M. Kupfer, Stephan A. Kohlhoff, Tamar A. Smith-Norowitz This study aims to assess prospectively whether there is an association between frequencies of upper respiratory tract infections (URTI) or asthma in early childhood and failed otoacoustic emission (OAE) screenings later in life. There are no clear recommendations for hearing testing following acute otitis media (AOM) infection. This is a retrospective, practice based chart review. Participants from a primary care setting were 517 pre-adolescent and adolescent children (49.9% female) (ages 10–21; mean, 15 y/o), who had presented with at least one specific bacterial URTI (AOM, Group A Streptococcus (GAS) tonsillitis, or Influenza) during childhood. Hearing testing was recorded incidentally at all subsequent routine health care maintenance visits (OAE hearing screen). Simple linear regression analyses were performed using R (v3.4.4). We found that number of episodes of AOM infections strongly correlated with number of failed OAE screenings later in life (F = 76.37; P =…

Ching-Fu Weng, Li-Ju Chen, Chih-Wan Lin, Ho-Min Chen, Henry Hsin-Chung Lee, Thai-Yen Ling, Fei-Yuan Hsiao

Redlberger-Fritz M, Vietzen H, Puchhammer-Stöckl E.

AbstractNK-cell response against influenza viruses partly depends on expression of CD112, a ligand for NK-cell receptor CD226 (DNAM-1). We analyzed whether distinct CD226 variants are associated with influenza disease severity. Comparison between 145 patients hospitalized with severe influenza at intensive care units (ICU) with 139 matched influenza-positive outpatients showed that especially presence of the rs763362 G allele (GG, AG) was associated with occurrence of severe influenza infections (p=0.0076). Also a higher frequency of the rs727088 G allele and rs763361 T allele were observed in the ICU group. Thus, CD226 variants may contribute to the severity of influenza virus disease.

Gubareva L, Fry A.

Drug resistance is a topic of significant concern in the treatment of infectious diseases caused by rapidly evolving RNA viruses that can persist (eg, human immunodeficiency virus and hepatitis C virus) or reinfect (eg, influenza virus). Combination drug therapy is standard of care for the treatment of infections by rapidly mutating RNA viruses [1, 2]. However, it is not a common approach for treating influenza virus infections, partly because of the limited number of anti-influenza drugs and drug targets. We now know that all of the classes of anti-influenza drugs—M2 blockers, neuraminidase inhibitors (NAIs), and the newly licensed cap-dependent endonuclease inhibitor (baloxavir marboxil)—have low genetic barriers to resistance: 1 or 2 amino acid substitutions are sufficient to gain resistance [3, 4].

Keita Fukao, Yoshinori Ando, Takeshi Noshi, Mitsutaka Kitano, Takahiro Noda, Makoto Kawai, Ryu Yoshida, Akihiko Sato, Takao Shishido, Akira Naito

by Keita Fukao, Yoshinori Ando, Takeshi Noshi, Mitsutaka Kitano, Takahiro Noda, Makoto Kawai, Ryu Yoshida, Akihiko Sato, Takao Shishido, Akira Naito Baloxavir marboxil (BXM) is an orally available small molecule inhibitor of cap-dependent endonuclease (CEN), an essential enzyme in the initiation of mRNA synthesis of influenza viruses. In the present study, we evaluated the efficacy of BXM against influenza virus infection in mouse models. Single-day oral administration of BXM completely prevented mortality due to infection with influenza A and B virus in mice. Moreover, 5-day repeated administration of BXM was more effective for reducing mortality and body weight loss in mice infected with influenza A virus than oseltamivir phosphate (OSP), even when the treatment was delayed up to 96 hours post infection (p.i.). Notably, administration of BXM, starting at 72 hours p.i. led to significant decrease in virus titers of >2-log10 reduction compared to the vehicle control within 24 hours after administration. Virus reduction in the lung was significantly greater than that observed with OSP. In addition, profound and sustained reduction of virus titer was observed in the immunocompromised mouse model without emergence of variants possessing treatment-emergent amino acid substitutions in the target protein. In our immunocompetent and immunocompromised mouse models, delayed treatment with BXM resulted in rapid and potent reduction in infectious virus titer and prevention of signs of influenza infection, suggesting that BXM could extend the therapeutic window for patients with influenza virus infection regardless of the host immune status.

Budd A, Beacham L, Smith C, et al.

AbstractBackgroundThe evolution of influenza A viruses results in birth cohorts that have different initial influenza virus exposures. Historically, A/H3 predominant seasons have been associated with more severe influenza-associated disease; however, since the 2009 pandemic there are suggestions that some birth cohorts experience more severe illness in A/H1 predominant seasons.MethodsU.S. influenza virologic, hospitalization and mortality surveillance data during 2000-2017 were analyzed for cohorts born between 1918 and 1989 that likely had different initial influenza virus exposures based on viruses circulating during early childhood. Relative risk/rate during H3 compared to H1 predominant seasons during pre-pandemic versus pandemic and later periods were calculated for each cohort.ResultsDuring the pre-pandemic period, all cohorts had more influenza-associated disease during H3 predominant seasons than H1 predominant seasons. During the pandemic and later period, four cohorts had higher hospitalization and mortality rates during H1 predominant seasons than H3 predominant seasons.DiscussionBirth cohort differences in risk of influenza-associated disease by influenza A virus subtype can be seen in U.S. influenza surveillance data and differ between pre-pandemic and pandemic and later periods. As the population ages, the amount of influenza-associated disease may be greater in future H1 predominant seasons than H3 predominant seasons.

Grazieli Maboni, Mauricio Seguel, Ana Lorton, Roy Berghaus, Susan Sanchez

by Grazieli Maboni, Mauricio Seguel, Ana Lorton, Roy Berghaus, Susan Sanchez Canine infectious respiratory disease (CIRD) is a syndrome where multiple viral and bacterial pathogens are involved sequentially or synergistically to cause illness. There is limited information regarding the prevalence of pathogens related to CIRD in the United States as well as the role of co-infections in the pathogenesis of the syndrome. We aimed to conduct a comprehensive etiologic and epidemiologic study of multiple CIRD agents in a diverse dog population using molecular methods and statistical modeling analyses. In addition, a novel probe-based multiplex real-time PCR was developed to simultaneously detect and differentiate two species of Mycoplasma (M. canis and M. cynos). Canine adenovirus, canine distemper virus, canine parainfluenza virus, coronavirus, influenza A virus (H3N2 and H3N8), Bordetella bronchiseptica, M. canis, M. cynos and Streptococcus equi subsp. zooepidemicus were investigated in specimens from clinically ill and asymptomatic dogs received at the Athens Veterinary Diagnostic Laboratory. Results showed low occurrence of classical CIRD agents such as B. bronchiseptica, canine adenovirus and distemper virus, while highlighting the potential role of emerging bacteria such as M. canis and M. cynos. Statistical modeling analyses of CIRD pathogens emphasized the impact of co-infections on the severity of clinical presentation, and showed that host factors, such as animal age, are the most important predictors of disease severity. This study provides new insights into the current understanding of the prevalence and role of co-infections with selected viruses and bacteria in the etiology of CIRD, while underscoring the importance of molecular diagnosis and vaccination against this disease.

Skowronski D, De Serres G, Orenstein W.

Abstract Background We assessed the utility of a multi-target, real-time PCR assay for Bordetella pertussis detection and diagnosis in patients with severe respiratory illness (SRI), influenza-like illness (ILI), and asymptomatic controls. Methods Real-time PCR detection of IS481, pIS1001, hIS1001 and ptxS1 was performed on nasopharyngeal specimens (SRI, ILI and controls) and induced sputum (SRI) collected from June 2012 to May 2016 through respiratory illness surveillance. Using PCR cycle threshold (Ct) value cut-offs, IS481 positive cases were classified as confirmed (Ct 

Abstract Background To improve national influenza vaccination recommendations, additional data on influenza A and B virus circulation are needed. Here, we describe the circulation of influenza A and B in the Czech Republic during 16 seasons. Methods This was a retrospective analysis of data collected from the 2000–2001 to 2015–2016 influenza seasons by the Czech Republic national influenza surveillance network. Influenza was confirmed and viral isolates subtyped by virological assays followed by antigen detection or by reverse transcriptase-polymerase chain reaction. Results Of 16,940 samples collected, 5144 (30.4%) were influenza-positive. Influenza A represented 78.6% of positive cases overall and accounted for more than 55.0% of all influenza cases in every season, except for 2005–2006 (6.0%). Both A/H1N1 and A/H3N2 were detected in most seasons, except for 2001–2002 and 2003–2004 (only A/H3N2), and 2007–2008 and 2009–2010 (only A/H1N1). Influenza B represented 21.4% of positive cases overall (range, 0.0–94.0% per season). Both influenza B lineages were detected in three seasons, a single B lineage in 11, and no B strain in two. For the 11 seasons where influenza B accounted for ≥20% of positive cases, the dominant lineage was Yamagata in six and Victoria in four. In the remaining season, the two lineages co-circulated. For two seasons (2005–2006 and 2007–2008), the B lineage in the trivalent influenza vaccine did not match the dominant circulating B lineage. Conclusions In the Czech Republic, during the 2000–2001 to 2015–2016 influenza seasons, influenza virus circulation varied considerably. Although influenza A accounted for the most cases in almost all seasons, influenza B made a substantial, sometimes dominant, contribution to influenza disease.…

Abstract Background A severe seasonal influenza epidemic was observed during 2017–2018 in China, prompting questions on clinical characteristics and outcomes of severe cases with influenza. Methods We retrospectively collected clinical data and outcomes of laboratory-confirmed hospitalized patients (severe to critical) during Jan-2011 to Feb-2018 from five hospitals, followed by a systematic analysis of cases from 2017 to 2018 (n = 289) and all previous epidemics during 2011–2017 (n = 169). Results In-hospital fatality was over 5-folds higher during the 2017–2018 (p 

Peipei Zhong, Hailin Zhang, Xiaofang Chen, Fangfang Lv

Abstract Background Human parainfluenza virus (HPIV), usually combined with other pathogens, causes lower respiratory tract infection (LRTI) in children. However, clinical characteristics of HPIV coinfection with other pathogens were unclear. This study aimed to investigate the viral and atypical bacterial etiology of LRTI in children and compare the clinical characteristics of HPIV single infection with those of coinfection. Methods This study included 1335 patients, aged between 1 to 71 months, diagnosed with LRTI in Yuying Children's Hospital, Zhejiang, China, from December 2013 to June 2015. Nasopharyngeal secretions were collected, and respiratory pathogens were detected using Multiplex polymerase chain reaction. The clinical data of patients were collected and analyzed. Results At least 1 pathogen was detected in 1181/1335 (88.5%) patients. The pathogens identified most frequently were respiratory syncytial virus, human rhinovirus, HPIV, adenovirus, and human metapneumovirus. The coinfection rate was 24.8%. HPIV coinfection with other viruses was more associated with running nose, shortness of breath, and oxygen support compared with HPIV single infection. Moreover, HPIV coinfection with atypical bacteria was more related to running nose, moist rales, and longer hospital duration compared with HPIV single infection, and also to longer hospital duration compared with coinfection with other viruses. Conclusions This study demonstrated that viral infections were highly associated with LRTI and the rate of coinfection was high. HPIV single infection was milder than coinfection with other viruses. Moreover, HPIV coinfection with atypical bacteria was more serious than HPIV single infection and coinfection with other viruses. This article is protected by copyright. All rights reserved.

ter Horst L, Brouwer M, van der Ende A, et al.

AbstractBackgroundCerebrospinal fluid (CSF) leakage is a risk factor for developing bacterial meningitis.Materials/methodsWe analyzed episodes of community-acquired bacterial meningitis associated with CSF leakage from a prospective nationwide cohort study.ResultsCSF leakage was identified in 65 episodes of 2022 episodes (3%) in 53 patients. The cause of CSF leakage was identified in 49 of 65 episodes (75%), most and most commonly consisted of ear-nose-throat surgery (19 of 49 episodes [29%]) and remote head trauma (15 of 49 episodes [23%]). The episode was a recurrent meningitis episode in 38 patients (59%). Of the recurrent episodes, 27 had known CSF leakage (71%) of whom 20 (53%) had previous surgery aiming to close the leak. Nine patients (38%) with known CSF leakage had been vaccinated (23-valent pneumococcal vaccine in 9 patients, meningococcal serogroup C vaccine in 2, meningococcal serogroup A and Haemophilus influenzae type b vaccine each in 1 patient). Streptococcus pneumoniae was cultured in 33 episodes (51%) and H. influenzae in 11 episodes (17%). Most common pneumococcal serotype were 3 (4 episodes), 35B, 9N, 38 and 15C (each 2 episodes). H. influenzae was unencapsulated in all 10 episodes with known capsule type. The outcome was unfavorable in 8 episodes (12%) and no patient died.ConclusionBacterial meningitis in patients with CSF leakage have a high recurrence rate, despite surgical repair or vaccination, and outcome is generally favorable. CSF leakage should be suspected in patients with bacterial meningitis presenting with liquorrhoea, recurrent meningitis or with disease caused by H. influenzae.

Hsueh-Ju Chen, Chia-Ping Su, Ming-Tsan Liu, Tsung-Pei Tsou

Influenza B viruses can be divided into two antigenically and genetically distinct lineages, represented by B/Victoria/2/87 and B/Yamagata/16/88 viruses (Rota et al., 1990). These lineages have co-circulated since 2001 in variable, unpredictable proportions (Ray et al., 2017). In Taiwan, the two lineages of influenza B viruses evolved contemporaneously and independently (Yang et al., 2012; Kuo et al., 2016). Influenza B viruses are generally thought to affect a younger population and cause less severe illness than influenza A viruses (Chi et al., 2008; Caini et al., 2015; Jennings et al., 2018).

Abstract Background Influenza and pneumococcal vaccine uptake in the older population aged 65 years or over of Hong Kong dramatically increased since the 2003 SARS outbreak. This study is aimed to evaluate the impact of increased coverage of influenza and pneumococcal vaccines by comparing the change of disease burden in the older population of Hong Kong, with the burden in the older population of Brisbane with relatively high vaccine coverage in the past fifteen years. Methods Time series segmented regression models were applied to weekly numbers of cause-specific mortality or hospitalization of Hong Kong and Brisbane. Annual excess rates of mortality or hospitalization associated with influenza in the older population were estimated for the pre-SARS (reference period), post-SARS and post-pandemic period, respectively. The rate ratios (RRs) between these periods were also calculated to assess the relative change of disease burden. Results Compared to the pre-SARS period, excess rates of mortality associated with influenza during the post-SARS period in Hong Kong decreased for cardiorespiratory diseases (RR = 0.90, 95% CI 0.80, 1.01), stroke (RR = 0.74, 95% CI 0.50, 1.09), and ischemic heart diseases (RR = 0.45, 95% CI 0.34, 0.58). The corresponding RRs in Brisbane were 0.79 (95% CI 0.54, 1.15), 0.33 (0.13, 0.80), and 1.09 (0.62, 1.90), respectively. Only the mortality of ischemic heart diseases showed a greater reduction in Hong Kong than in Brisbane. During the post-pandemic period, excess rates of all-cause mortality increased in Hong Kong, but to a lesser extent than in Brisbane (RR = 1.41 vs 2.39). Conclusion A relative decrease (or less of an increase) of influenza disease burden was observed in the older population of Hong Kong after increased coverage of influenza and pneumococcal vaccines in this population, as compared to those of Brisbane where vaccination rates remained stable. The lack of significant findings in some disease categories highlights the challenges of evaluating the benefits of vaccination at the population level.…

Musa Hindiyeh, Orna Mor, Rakefet Pando, Batya Mannasse, Areej Kabat, Hadar Assraf-Zarfati, Ella Mendelson, Danit Sofer, Michal Mandelboim

by Musa Hindiyeh, Orna Mor, Rakefet Pando, Batya Mannasse, Areej Kabat, Hadar Assraf-Zarfati, Ella Mendelson, Danit Sofer, Michal Mandelboim Respiratory viral infections constitute the majority of samples tested in the clinical virology laboratory during the winter season, and are mainly diagnosed using molecular assays, namely real-time PCR (qPCR). Therefore, a high-quality extraction process is critical for successful, reliable and sensitive qPCR results. Here we aimed to evaluate the performance of the newly launched eMAG compared to the fully automated MagNA PURE 96 (Roche, Germany) and to the semi-automated easyMAG (bioMerieux, France) extraction platforms. For this analysis, we assessed and compared the analytic and clinical performance of the three platforms, using 262 archived respiratory samples positive or negative to common viruses regularly examined in our laboratory (influenza A, B, H1N1pdm, Respiratory Syncytial Virus (RSV), human Metapneumovirus (hMPV), parainfluenza-3, adenovirus and negative samples). In addition, quantitated virus controls were used to determine the limit of detection of each extraction method. In all categories tested, eMAG results were comparable to those of the easyMAG and MagNa PURE 96, highly sensitive for all viruses and over 98% clinical specificity and sensitivity for all viruses tested. Together with its high level of automation, the bioMerieux eMAG is a high-quality extraction platform enabling effective molecular analysis and is mostly suitable for medium-sized laboratories.

Lindsey B, Höschler K, de Silva T.

LAIVinfluenzaimmunogenicityshedding…

Marta Sisteré-Oró, Júlia Vergara-Alert, Thomas Stratmann, Sergi López-Serrano, Sonia Pina-Pedrero, Lorena Córdoba, Mónica Pérez-Maillo, Patrícia Pleguezuelos, Enric Vidal, Veljko Veljkovic, Joaquim Segalés, Jens Nielsen, Anders Fomsgaard, Ayub Darji

by Marta Sisteré-Oró, Júlia Vergara-Alert, Thomas Stratmann, Sergi López-Serrano, Sonia Pina-Pedrero, Lorena Córdoba, Mónica Pérez-Maillo, Patrícia Pleguezuelos, Enric Vidal, Veljko Veljkovic, Joaquim Segalés, Jens Nielsen, Anders Fomsgaard, Ayub Darji Swine influenza viruses (SIVs), the causal agents of swine influenza, are not only important to control due to the economic losses in the swine industry, but also can be pandemic pathogens. Vaccination is one of the most relevant strategies to control and prevent influenza infection. Current human vaccines against influenza induce strain-specific immunity and annual update is required due to the virus antigenic shift phenomena. Previously, our group has reported the use of conserved hemagglutinin peptides (HA-peptides) derived from H1-influenza virus as a potential multivalent vaccine candidate. Immunization of swine with these HA-peptides elicited antibodies that recognized and neutralized heterologous influenza viruses in vitro and demonstrated strong hemagglutination-inhibiting activity. In the present work, we cloned one HA-peptide (named NG34) into a plasmid fused with cytotoxic T lymphocyte-associated antigen (CTLA4) which is a molecule that modifies T cell activation and with an adjuvant activity interfering with the adaptive immune response. The resulting plasmid, named pCMV-CTLA4-Ig-NG34, was administered twice to animals employing a needle-free delivery approach. Two studies were carried out to test the efficacy of pCMV-CTLA4-Ig-NG34 as a potential swine influenza vaccine, one in seronegative and another in seropositive pigs against SIV. The second one was aimed to evaluate whether pCMV-CTLA4-Ig-NG34 vaccination would overcome maternally derived antibodies (MDA). After immunization, all animals were intranasally challenged with an H3N2 influenza strain. A complete elimination or significant reduction in the viral shedding was observed within the first week after the challenge in the vaccinated animals from both studies. In addition, no challenged heterologous virus load was detected in the airways of vaccinated pigs. Overall, it is suggested that the pCMV-CTLA4-Ig-NG34 vaccine formulation could potentially be used as a multivalent vaccine against influenza viruses.

Abstract Background Hepatitis C Virus is becoming a major health problem in Asia and across the globe since it is causing serious liver diseases including liver cirrhosis, chronic hepatitis and hepatocarcinoma (HCC). Protein interaction networks presents us innumerable novel insights into functional constitution of proteome and helps us finding potential candidates for targeting the drugs. Methods Here we present a comprehensive protein interaction network of Hepatitis C Virus with its host, constructed by literature curated interactions. The network was constructed and explored using Cytoscape and the results were further analyzed using KEGG pathway, Gene Ontology enrichment analysis and MCODE. Results We found 1325 interactions between 12 HCV proteins and 940 human genes, among which 21 were intraviral and 1304 were HCV-Human. By analyzing the network, we found potential human gene list with their number of interactions with HCV proteins. ANXA2 and NR4A1 were interacting with 6 HCV proteins while we found 11 human genes which were interacting with 5 HCV proteins. Furthermore, the enrichment analysis and Gene Ontology of the top genes to find the pathways and the biological processes enriched with those genes. Among the viral proteins, NS3 was interacting with most number of interactors followed by NS5A and so on. KEGG pathway analysis of three set of most HCV- associated human genes was performed to find out which gene products are involved in certain disease pathways. Top 5, 10 and 20 human genes with most interactions were analyzed which revealed some striking results among which the top 10 host genes came up to be significant because they were more related to Influenza A viral infection previously. This insight provides us with a clue that the set of genes are highly enriched in HCV but are not well studied in its infection pathway. Conclusions We found out a group of proteins which were rich in HCV viral pathway but there were no drugs targeting them according to the drug repurposing hub. It can be concluded that the cluster we obtained from MCODE contains potential targets for HCV treatment and could be implemented for molecular docking and drug designing further by the scientists.…

Abstract Background Medical masks are commonly used in health care settings to protect healthcare workers (HCWs) from respiratory and other infections. Airborne respiratory pathogens may settle on the surface of used masks layers, resulting in contamination. The main aim of this study was to study the presence of viruses on the surface of medical masks. Methods Two pilot studies in laboratory and clinical settings were carried out to determine the areas of masks likely to contain maximum viral particles. A laboratory study using a mannequin and fluorescent spray showed maximum particles concentrated on upper right, middle and left sections of the medical masks. These findings were confirmed through a small clinical study. The main study was then conducted in high-risk wards of three selected hospitals in Beijing China. Participants (n = 148) were asked to wear medical masks for a shift (6–8 h) or as long as they could tolerate. Used samples of medical masks were tested for presence of respiratory viruses in upper sections of the medical masks, in line with the pilot studies. Results Overall virus positivity rate was 10.1% (15/148). Commonly isolated viruses from masks samples were adenovirus (n = 7), bocavirus (n = 2), respiratory syncytial virus (n = 2) and influenza virus (n = 2). Virus positivity was significantly higher in masks samples worn for > 6 h (14.1%, 14/99 versus 1.2%, 1/49, OR 7.9, 95% CI 1.01–61.99) and in samples used by participants who examined > 25 patients per day (16.9%, 12/71 versus 3.9%, 3/77, OR 5.02, 95% CI 1.35–18.60). Most of the participants (83.8%, 124/148) reported at least one problem associated with mask use. Commonly reported problems were pressure on face (16.9%, 25/148), breathing difficulty (12.2%, 18/148), discomfort (9.5% 14/148), trouble communicating with the patient (7.4%, 11/148) and headache (6.1%, 9/148). Conclusion Respiratory pathogens on the outer surface of the used medical masks may result in self-contamination. The risk is higher with longer duration of mask use (> 6 h) and with higher rates of clinical contact. Protocols on duration of mask use should specify a maximum time of continuous use, and should consider guidance in high contact settings. Viruses were isolated from the upper sections of around 10% samples, but other sections of masks may also be contaminated. HCWs should be aware of these risks in order to protect themselves and people around them.…

L. Busson, M. Bartiaux, S. Brahim, D. Konopnicki, N. Dauby, M. Gérard, P. De Backer, K. Van Vaerenbergh, B. Mahadeb, L. Mekkaoui, M. De Foor, M. Wautier, O. Vandenberg, P. Mols, J. Levy, M. Hallin

Shiu, Eunice Y.C.; Leung, Nancy H.L.; Cowling, Benjamin J.

Purpose of review Health agencies recommend transmission-based precautions, including contact, droplet and airborne precautions, to mitigate transmission of respiratory viruses in healthcare settings. There is particular controversy over the importance of aerosol transmission and whether airborne precautions should be recommended for some respiratory viruses. Here, we review the current recommendations of transmission-based precautions and the latest evidence on the aerosol transmission of respiratory viruses. Recent findings Viral nucleic acids, and in some instances viable viruses, have been detected in aerosols in the air in healthcare settings for some respiratory viruses such as seasonal and avian influenza viruses, Middle East respiratory syndrome-coronavirus and respiratory syncytial virus. However, current evidences are yet to demonstrate that these viruses can effectively spread via airborne route between individuals, or whether preventive measures in airborne precautions would be effective. Summary Studies that use transmission events as outcome to demonstrate human-to-human transmission over the aerosol route or quantitative measurement of infectious respiratory viruses in the air are needed to evaluate the infectiousness of respiratory viruses over the aerosol route. When a respiratory virus in concern only leads to disease with low severity, airborne precautions are not likely to be justified. Correspondence to Dr Nancy H.L. Leung, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 7 Sassoon Road, Pokfulam, Hong Kong Special Administrative Region, China. Tel: +852 3917 6757; fax: +852 2855 9528; e-mail: leungnan@hku.hk Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

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After publication of the original article [1], in Table 1, in the second and third column, “Vacnee” and “Non-vacnee” should be replaced with “Vaccinee” and “Non-vaccinee”.…

Following publication…

Following publication of the original article [1], the author reported an error in the title:…

Mini Singh, Jenny-Ann Toribio, Angela Bullanday Scott, Peter Groves, Belinda Barnes, Kathryn Glass, Barbara Moloney, Amanda Black, Marta Hernandez-Jover

by Mini Singh, Jenny-Ann Toribio, Angela Bullanday Scott, Peter Groves, Belinda Barnes, Kathryn Glass, Barbara Moloney, Amanda Black, Marta Hernandez-Jover…

The PLOS ONE Staff

by The PLOS ONE Staff …

Samuel K. Peasah, Martin I. Meltzer, Michelle Vu, Danielle L. Moulia, Carolyn B. Bridges

by Samuel K. Peasah, Martin I. Meltzer, Michelle Vu, Danielle L. Moulia, Carolyn B. Bridges Background Although influenza vaccination has been shown to reduce the incidence of major adverse cardiac events (MACE) among those with existing cardiovascular disease (CVD), in the 2015–16 season, coverage for persons with heart disease was only 48% in the US. Methods We built a Monte Carlo (probabilistic) spreadsheet-based decision tree in 2018 to estimate the cost-effectiveness of increased influenza vaccination to prevent MACE readmissions. We based our model on current US influenza vaccination coverage of the estimated 493,750 US acute coronary syndrome (ACS) patients from the healthcare payer perspective. We excluded outpatient costs and time lost from work and included only hospitalization and vaccination costs. We also estimated the incremental cost/MACE case averted and incremental cost/QALY gained (ICER) if 75% hospitalized ACS patients were vaccinated by discharge and estimated the impact of increasing vaccination coverage incrementally by 5% up to 95% in a sensitivity analysis, among hospitalized adults aged ≥ 65 years and 18–64 years, and varying vaccine effectiveness from 30–40%. Result At 75% vaccination coverage by discharge, vaccination was cost-saving from the healthcare payer perspective in adults ≥ 65 years and the ICER was $12,680/QALY (95% CI: 6,273–20,264) in adults 18–64 years and $2,400 (95% CI: -1,992–7,398) in all adults 18 + years. These resulted in ~ 500 (95% CI: 439–625) additional averted MACEs/year for all adult patients aged ≥18 years and added ~700 (95% CI: 578–825) QALYs. In the sensitivity analysis, vaccination becomes cost-saving in adults 18+years after about 80% vaccination rate. To achieve 75% vaccination rate in all adults aged ≥ 18 years will require an additional cost of $3 million. The effectiveness of the vaccine, cost of vaccination, and vaccination coverage rate had the most impact on the results. Conclusion Increasing vaccination rate among hospitalized ACS patients has a favorable cost-effectiveness profile and becomes cost-saving when at least 80% are vaccinated.…

Sanjay S. Patel, Svetlana Bizjajeva, Kelly Lindert, Esther Heijnen, Janine Oberye

Influenza represents a significant burden in children—a fact that became apparent during the 2017-2018 season, in which an epidemic led to the highest rate of influenza-related hospitalizations ever reported and an increase in deaths due to influenza among children and adults (Rolfes et al., 2019). Because children are not only susceptible to influenza but also can transmit the disease to other vulnerable members of their household, seasonal influenza vaccination is recommended for children ≥6 months of age in the United States (Grohskopf et al., 2017).

Ray G, Lewis N, Klein N, et al.

AbstractBias arises in studies of waning vaccine effectiveness when higher-risk individuals are depleted from the population at-risk, at different rates between study groups. We examine how this bias arises and how it can be avoided. Reanalysis of data from California confirms a finding of intra-season waning of influenza vaccine effectiveness.

Dugas A, Hsieh Y, Lovecchio F, et al.

AbstractStudy objectiveAccurate diagnosis of influenza is essential for appropriate antiviral treatment in accordance with Centers for Disease Control and Prevention (CDC) guidelines. However, no clear guidance exists on whom should be tested. We sought to develop a clinical decision guideline (CDG) to inform influenza testing decisions for adult emergency department (ED) patients deemed appropriate for antiviral treatment by CDC guidelines.MethodsProspective cohort study was performed at four U.S. EDs. From November 2013 to April 2014 we enrolled adult ED patients with fever or respiratory symptoms, who met criteria for antiviral treatment per 2013 CDC guidelines. All patients were tested for influenza using PCR. Data were randomly split into derivation (80%) and validation (20%) datasets. A discrete set of independent variables was selected by logistic regression using the derivation set to create a scoring system, with a target sensitivity of at least 90%. The derived CDG was then validated.ResultsOf 1941 enrolled participants, 183 (9.4%) had influenza. The derived CDG included new or increased cough (2 points), headache (1 point), subjective fever (1 point), and triage temperature >100.4°C (1 point), with a score of ≥3 indicating influenza testing was warranted. The CDG had a sensitivity and specificity of 94.1% and 36.6% in the derivation set, and 91.5% and 34.6% in the validation set, respectively.ConclusionA CDG with high sensitivity was derived and validated. Incorporation into practice could standardize testing for high-risk patients in adult EDs during influenza seasons, potentially improving diagnosis and treatment.Clinical Trial RegistrationNCT01947049…