Circulation and seasonality of influenza viruses in different transmission zones in Africa.

BACKGROUND: Influenza is responsible for more than 5 million severe cases and 290,000 to 650,000 deaths every year worldwide. Developing countries account for 99% of influenza deaths in children under 5 years of age. This paper aimed to determine the dynamics of influenza viruses in African transmission areas to identify regional seasonality for appropriate decision-making and the development of regional preparedness and response strategies. METHODS: We used data from the WHO FluMart website collected by National Influenza Centers for seven transmission periods (2013-2019). We calculated weekly proportions of positive influenza cases and determined transmission trends in African countries to determine the seasonality. RESULTS: From 2013 to 2019, influenza A(H1N1)pdm2009, A(H3N2), and A(H5N1) viruses, as well as influenza B Victoria and Yamagata lineages, circulated in African regions. Influenza A(H1N1)pdm2009 and A(H3N2) highly circulated in northern and southern Africa regions. Influenza activity followed annual and regional variations. In the tropical zone, from eastern to western via the middle regions, influenza activities were marked by the predominance of influenza A subtypes despite the circulation of B lineages. One season was identified for both the southern and northern regions of Africa. In the eastern zone, four influenza seasons were differentiated, and three were differentiated in the western zone. CONCLUSION: Circulation dynamics determined five intense influenza activity zones in Africa. In the tropics, influenza virus circulation waves move from the east to the west, while alternative seasons have been identified in northern and southern temperate zones. Health authorities from countries with the same transmission zone, even in the absence of local data based on an established surveillance system, should implement concerted preparedness and control activities, such as vaccination.

Clinical validation of a multiplex PCR-based detection assay using saliva or nasopharyngeal samples for SARS-Cov-2, influenza A and B.

The COVID-19 pandemic has resulted in significant diversion of human and material resources to COVID-19 diagnostics, to the extent that influenza viruses and co-infection in COVID-19 patients remains undocumented and pose serious public-health consequences. We optimized and validated a highly sensitive RT-PCR based multiplex-assay for the detection of SARS-CoV-2, influenza A and B viruses in a single-test. This study evaluated clinical specimens (n = 1411), 1019 saliva and 392 nasopharyngeal swab (NPS), tested using two-assays: FDA-EUA approved SARS-CoV-2 assay that targets N and ORF1ab gene, and the PKamp-RT-PCR based assay that targets SARS-CoV-2, influenza viruses A and B. Of the 1019 saliva samples, 17.0% (174/1019) tested positive for SARS-CoV-2 using either assay. The detection rate for SARS-CoV-2 was higher with the multiplex assay compared to SARS-specific assay [91.9% (160/174) vs. 87.9% (153/174)], respectively. Of the 392 NPS samples, 10.4% (41/392) tested positive for SARS-CoV-2 using either assay. The detection rate for SARS-CoV-2 was higher with the multiplex assay compared to SARS-specific assay [97.5% (40/41) vs. 92.1% (39/41)], respectively. This study presents clinical validation of a multiplex-PCR assay for testing SARS-CoV-2, influenza A and B viruses, using NPS and saliva samples, and demonstrates the feasibility of implementing the assay without disrupting the existing laboratory workflow.

Evaluation of the Alinity m Resp-4-Plex Assay for the Detection of Severe Acute Respiratory Syndrome Coronavirus 2, Influenza A Virus, Influenza B Virus, and Respiratory Syncytial Virus.

The rapid emergence of the coronavirus disease 2019 (COVID-19) pandemic has introduced a new challenge in diagnosing and differentiating respiratory infections. Accurate diagnosis of respiratory infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is complicated by overlapping symptomology, and stepwise approaches to testing for each infection would lead to increased reagent usage and cost, as well as delays in clinical interventions. To avoid these issues, multiplex molecular assays have been developed to differentiate between respiratory viruses in a single test to meet clinical diagnostic needs. To evaluate the analytical performance of the FDA emergency use authorization (EUA)-approved Abbott Alinity m resp-4-plex assay (Alinity m) in testing for SARS-CoV-2, influenza A virus, influenza B virus, and respiratory syncytial virus (RSV), we compared its performance to those of both the EUA-approved Cepheid Xpert Xpress SARS-CoV-2, influenza A/B virus, and RSV assay (Xpert Xpress) and the EUA-approved Roche Cobas SARS-CoV-2 and influenza A/B virus assay (Cobas) in a single-center retrospective analysis. High concordance was observed among all three assays, with kappa statistics showing an almost perfect agreement (>0.90). The limit of detection (LOD) results for SARS-CoV-2 showed the Alinity m exhibiting the lowest LOD at 26 copies/mL, followed by the Cobas at 58 copies/mL and the Xpert Xpress at 83 copies/mL, with LOD results for the influenza A virus, influenza B virus, and RSV viral targets also showing equivalent or better performance on the Alinity m compared to the other two platforms. The Alinity m can be used as a high-volume testing platform for SARS-CoV-2, influenza A virus, influenza B virus, and RSV and exhibits analytical performance comparable to those of both the Xpert Xpress and Cobas assays. IMPORTANCE The rapid emergence of SARS-CoV-2 has introduced a new challenge in diagnosing and differentiating respiratory infections, especially considering the overlapping symptomology of many of these infections and differences in clinical interventions depending on the pathogen identified. To avoid these issues, multiplex molecular assays like the one described in this article need to be developed to differentiate between the most common respiratory pathogens in a single test and most effectively meet clinical diagnostic needs.

Severe influenza virus infection in children admitted to the PICU: Comparison of influenza A and influenza B virus infection.

Although the influenza virus usually causes a self-limiting disease, deaths are reported even in children without risk factors. We aimed to identify the clinical features, mortality associated with severe influenza A and B virus infections of children admitted to the pediatric intensive care unit (PICU). We conducted a retrospective study of children with confirmed influenza infection between 2012 and 2019 who were admitted to the PICU. Demographic features, risk factors, clinical data, microbiological data, complications, and outcomes were collected. Over seven influenza seasons (2012-2011 to 2015-2016), 713 children diagnosed with laboratory-confirmed influenza-related LRTI, and PICU admission was needed in 6% (46/713) of the patients. Thirty-one patients (67.4%) were diagnosed with influenza A and 15 patients were diagnosed with influenza B. Epidemiologic and clinical characteristics were similar in both influenza types, lactate dehydrogenase levels were significantly higher for influenza A than for influenza B infections. Although the influenza A to B ratio among the patients admitted to the PICU was 2.06, the percentage of cases requiring PICU admission was nearly two times higher in influenza B cases. There was no statistically significant difference in disease severity and complications in patients with influenza A and influenza B.

No evidence of SARS-CoV-2 in hospitalized patients with severe acute respiratory syndrome in five Italian hospitals from 1st November 2019 to 29th February 2020.

BACKGROUND: On 9th January 2020, China CDC reported a novel coronavirus (later named SARS-CoV-2) as the causative agent of the coronavirus disease 2019 (COVID-19). Identifying the first appearance of virus is of epidemiological importance to tracking and mapping the spread of SARS-CoV-2 in a country. We therefore conducted a retrospective observational study to detect SARS-CoV-2 in oropharyngeal samples collected from hospitalized patients with a Severe Acute Respiratory Infection (SARI) enrolled in the DRIVE (Development of Robust and Innovative Vaccine Effectiveness) study in five Italian hospitals (CIRI-IT BIVE hospitals network) (1st November 2019 - 29th February 2020). OBJECTIVES: To acquire new information on the real trend in SARS-CoV-2 infection during pandemic phase I and to determine the possible early appearance of the virus in Italy. MATERIALS AND METHODS: Samples were tested for influenza [RT-PCR assay (A/H1N1, A/H3N2, B/Yam, B/Vic)] in accordance with the DRIVE study protocol. Subsequently, swabs underwent molecular testing for SARS-COV-2. [one-step real-time multiplex retro-transcription (RT) PCR]. RESULTS: In the 1683 samples collected, no evidence of SARS-CoV-2 was found. Moreover, 28.3% (477/1683) of swabs were positive for influenza viruses, the majority being type A (358 vs 119 type B). A/H3N2 was predominant among influenza A viruses (55%); among influenza B viruses, B/Victoria was prevalent. The highest influenza incidence rate was reported in patients aged 0-17 years (40.3%) followed by those aged 18-64 years (24.4%) and ≥65 years (14.8%). CONCLUSIONS: In Italy, some studies have shown the early circulation of SARS-CoV-2 in northern regions, those most severely affected during phase I of the pandemic. In central and southern regions, by contrast no early circulation of the virus was registered. These results are in line with ours. These findings highlight the need to continue to carry out retrospective studies, in order to understand the epidemiology of the novel coronavirus, to better identify the clinical characteristics of COVID-19 in comparison with other acute respiratory illnesses (ARI), and to evaluate the real burden of COVID-19 on the healthcare system.

Evaluation of Three Multiplex Real-time Reverse Transcription PCR Assays for Simultaneous Detection of SARS-CoV-2, Influenza A/B, and Respiratory Syncytial Virus in Nasopharyngeal Swabs.

BACKGROUND: In the coronavirus disease 2019 (COVID-19) pandemic era, the simultaneous detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus (Flu), and respiratory syncytial virus (RSV) is important in the rapid differential diagnosis in patients with respiratory symptoms. Three multiplex real-time reverse transcription polymerase chain reaction (rRT-PCR) assays have been recently developed commercially in Korea: PowerChek™ SARS-CoV-2, Influenza A&B Multiplex Real-time PCR Kit (PowerChek; KogeneBiotech); STANDARD™ M Flu/SARS-CoV-2 Real-time Detection Kit (STANDARD M; SD BioSensor); and Allplex™ SARS-CoV-2/FluA/FluB/RSV Assay (Allplex; Seegene). We evaluated the analytical and clinical performances of these kits. METHODS: A limit of detection tests were performed and cross-reactivity analysis was executed using clinical respiratory samples. Ninety-seven SARS-CoV-2-positive, 201 SARS-CoV-2-negative, 71 influenza A-positive, 50 influenza B-positive, 78 RSV-positive, and 207 other respiratory virus-positive nasopharyngeal swabs were tested using the three assays. The AdvanSure™ respiratory viruses rRT-PCR assay (AdvanSure; LG Life Sciences) was used as a comparator assay for RSV. RESULTS: Except in influenza B, in SARS-CoV-2 and influenza A, there were no significant differences in detecting specific genes of the viruses among the three assays. All three kits did not cross-react with common respiratory viruses. All three kits had greater than 92% positive percent agreement and negative percent agreement and ≥ 0.95 kappa value in the detection of SARS-CoV-2 and flu A/B. Allplex detected RSV more sensitively than AdvanSure. CONCLUSION: The overall performance of three multiplex rRT-PCR assays for the concurrent detection of SARS-CoV-2, influenza A/B, and RSV was comparable. These kits will promote prompt differential diagnosis of COVID-19, influenza, and RSV infection in the COVID-19 pandemic era.

Exploring the epidemiological changes of common respiratory viruses since the COVID-19 pandemic: a hospital study in Hangzhou, China.

Adenovirus, respiratory syncytial virus, and influenza virus are common causes of respiratory infections. The COVID-19 pandemic had a significant impact on their prevalence. The aim of this study was to analyze the epidemic changes of common respiratory viruses in the Affiliated Hospital of Hangzhou Normal University in Hangzhou, China, from October of 2017 to February of 2021. We collected statistics from 121,529 patients in the outpatient and inpatient departments of the hospital who had throat or nose swabs collected for testing for four virus antigens by the colloidal gold method. Of these, 13,200 (10.86%) were positive for influenza A virus, 8,402 (6.91%) were positive for influenza B virus, 6,056 (4.98%) were positive for adenovirus, and 4,739 (3.90%) were positive for respiratory syncytial virus. The positivity rates of the influenza A virus (0-14 years old, P = 0.376; over 14 years old, P = 0.197) and respiratory syncytial virus (0-14 years old, P = 0.763; over 14 years old, P = 0.465) did not differ significantly by gender. After January of 2020, influenza virus infection decreased significantly. The positivity rate of respiratory syncytial virus remained high, and its epidemic season was similar to before. Strict respiratory protection and regulation of crowd activities have a great impact on the epidemic characteristics of viruses. After major changes in the public health environment, virus epidemics and their mutations should be monitored closely, extensively, and continuously.

The first epidemiological and virological influenza surveillance in the Republic of Guinea revealed the predominance of influenza A/H3N2 and B Victoria viruses.

Little is known about respiratory viruses infection in Guinea. Influenza surveillance has not been implemented in Guinea mainly because of the paucity of laboratory infrastructure and capacity. This paper presents the first influenza surveillance data in Guinea.Swabs were obtained from August 2018 through December 2019 at influenza sentinel sites and transported to the Institut National de Santé Publique for testing. Ribonucleic acid was extracted and tested for the presence of influenza A and B by real-time reverse transcription-polymerase chain reaction (RT-PCR). Positive samples were further characterised to determine the subtypes and lineages of influenza viruses.A total of 862 swabs were collected and tested. Twenty-three per cent of samples tested positive for influenza A and B viruses. Characterisation of positive specimens identified influenza A/H1N1pmd09 (2.5%), influenza A/H3N2 (57.3%), influenza B/Victoria lineage (36.7%) and 7 (3.5%) influenza B with undetermined lineage. Influenza B virus activity clustered in August through November while influenza A/H3N2 displayed two clusters of activities that appeared in May through August and November through December.For the first time in Guinea, the epidemiology, diversity and period of circulation of influenza viruses were studied. The results indicate the predominance and the periods of activities of influenza B Victoria lineage and influenza A/H3N2 which are important information for preventive strategies. It is warranted to extend the influenza surveillance to other parts of Guinea to better understand the epidemiology of the viruses and monitor the emergence of influenza strains with pandemic potential.

Influenza B infection and Kawasaki disease in an adolescent during the COVID-19 pandemic: a case report. / Infecção por Influenza B e doença de Kawasaki em adolescente durante a pandemia da COVID-19: relato de caso.

We report a case of Influenza B infection and Kawasaki disease in an adolescent, diagnosed during the COVID-19 pandemic. An asthmatic female adolescent presented with fever and flu-like symptoms for 7 days and was admitted with acute respiratory failure requiring mechanical ventilation. She progressed with hemodynamic instability responsive to vasoactive drugs. Antibiotic therapy and support measures were introduced, showing progressive hemodynamics and respiratory improvement, however with persistent fever and increased inflammatory markers. During the hospitalization, she developed bilateral non-purulent conjunctivitis, hand and feet desquamation, strawberry tongue, and cervical adenopathy, and was diagnosed with Kawasaki disease. She was prescribed intravenous immunoglobulin and, due to the refractory clinical conditions, corticosteroid therapy was added; 24 hours later, the patient was afebrile. No coronary changes were found. A full viral panel including COVID-19 C-reactive protein and serology could only isolate the Influenza B virus. During the hospitalization, she was diagnosed with pulmonary thromboembolism; coagulopathies were investigated, and she was diagnosed with heterozygous factor V Leiden mutation. There is a potential association between Kawasaki disease and infection with Influenza B or with other viruses such as coronavirus. Therefore, this association should be considered in pediatric patients, adolescents included, with prolonged febrile conditions.

Apresentação de um caso de infecção por Influenza B e doença de Kawasaki em adolescente ocorrido durante a pandemia da COVID-19. Adolescente asmática evoluiu com febre e síndrome gripal por 7 dias e deu entrada com quadro de insuficiência respiratória aguda, necessitando de intubação orotraqueal. Evoluiu também com instabilidade hemodinâmica respondedora ao uso de droga vasoativa. Foram introduzidas antibioticoterapia e medidas de suporte. Apresentou melhora hemodinâmica e respiratória progressiva, porém mantinha febre e alteração de provas inflamatórias. Durante internação, evoluiu com conjuntivite não purulenta bilateral, descamação de mão e pés, língua em framboesa e linfonodomegalia cervical, recebendo diagnóstico de doença de Kawasaki. Recebeu gamaglobulina e, por conta de quadro clínico refratário, foi administrado também corticoide, evoluindo afebril 24 horas após. Não apresentou alterações coronarianas. O único agente isolado foi Influenza B, mesmo realizando painel viral e investigação para COVID-19 com reação em cadeia da polimerase e sorologia. Durante internação, apresentou tromboembolismo pulmonar, e, em investigação de coagulopatias, foi diagnosticada com mutação em heterozigose de fator V de Leiden. Há uma potencial associação entre doença de Kawasaki e infecção por Influenza B ou outros vírus, como o coronavírus e, por isso, esses diagnósticos devem ser investigados nos pacientes pediátricos, incluindo adolescentes, com quadros febris prolongados.

Epidemiology of Influenza Viruses and Viruses Causing Influenza-Like Illness in Children Under 14 Years Old in the 2018-2019 Epidemic Season in Poland.

BACKGROUND This study aimed to investigate the epidemiology of influenza viruses and viruses that caused influenza-like disease in children under 14 years of age in the 2018-2019 epidemic season in Poland, and to identify the public health lessons that can be learned. MATERIAL AND METHODS Nose and throat swabs were used to obtain samples. The samples were analyzed in the National Influenza Center, Department of Influenza Research at the National Institute of Public Health-National Institute of Hygiene as well as in 16 Voivodship Sanitary Epidemiological Stations across the country. Methods of RNA isolation depended on the laboratory where the isolation was performed. In all laboratories, quantitative polymerase chain reactions were used to determine the influenza virus type as well as the subtype. RESULTS The study group was confirmed to be infected with influenza A and B, with influenza A/H1N1/pdm09 as the dominant subtype. Among the age group of children up to 14 years of age, cases of infection with viruses that cause influenza-like disease were also reported. It was noticeable that the largest number of confirmed cases of infection was recorded in the group of the youngest children (0-4 years). In addition, several different variants of co-infection were registered. CONCLUSIONS This population study showed that in the 2018-2019 epidemic season in Poland children aged under 14 years were at risk of influenza virus infection and its complications. The presented data support increasing the percentage of children being vaccinated in Poland.

European multicenter evaluation of Xpert® Xpress SARS-CoV-2/Flu/RSV test.

Rapid diagnostics for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are paramount for reducing the spread of the current pandemic. During additional seasonal epidemics with influenza A/B and respiratory syncytial virus (RSV), the clinical signs and symptoms cannot be distinguished easily from SARS-CoV-2. Therefore, a new assay combining four targets in the form of the new Xpert Xpress SARS-CoV-2/Flu/RSV assay was evaluated. The assay was compared to the Xpert Xpress SARS-CoV-2, Xpert Xpress Flu/RSV, Seegene Flu/RSV, influenza A/B r-gene® and RSV/hMPV r-gene®. A total of 295 nasopharyngeal and throat swabs were tested at four institutes throughout Europe including 72 samples positive for SARS-CoV-2, 65 for influenza A, 47 for influenza B, and 77 for RSV. The sensitivity of the new assay was above 95% for all targets, with the highest for SARS-CoV-2 (97.2%). The overall correlation of SARS-CoV-2 Ct values between Xpert Xpress SARS-CoV-2 assay and Xpert Xpress SARS-CoV-2/Flu/RSV assay was high. The agreement between Ct values above 30 showed the multiplex giving higher Ct values for SARS-CoV-2 on average than the singleplex assay. In conclusion, the new assay is a rapid and reliable alternative with less hands-on time for the detection of not one, but four upper respiratory tract pathogens that may circulate at the same time.

Burden of critically ill patients with influenza in a French catchment population.

Despite the particular focus given to influenza since the 2009 influenza A(H1N1) pandemic, true burden of influenza-associated critical illness remains poorly known. The aim of this study was to identify factors influencing influenza burden imposed on intensive care units (ICUs) in a catchment population during recent influenza seasons. From 2008 to 2013, all adult patients admitted with a laboratory-confirmed influenza infection to one of the ICUs in the catchment area were prospectively included. A total of 201 patients (mean age: 63 ± 16, sex-ratio: 1.1) were included. The influenza-related ICU-bed occupancy rate averaged 4.3% over the five influenza seasons, with the highest mean occupancy rate (16.9%) observed during the 2012 winter. In-hospital mortality for the whole cohort was 26%. Influenza A(H1N1)pdm infections (pdm in the mentioned nomenclature refers to Pandemic Disease Mexico 2009), encountered in 51% of cases, were significantly associated with neither longer length of stay nor higher mortality (ICU and hospital) when compared to infections with other virus subtypes. SOFA score (OR, 1.12; 95% CI, 1.04-1.29) was the only independent factor significantly associated with a prolonged hospitalization. These results highlight both the frequency and the severity of influenza-associated critical illness, leading to a sustained activity in ICUs. Severity of the disease, but not A(H1N1)pdm virus, appears to be a major determinant of ICU burden related to influenza.

Molecular Detection of Influenza A and B Viruses in Four Consecutive Influenza Seasons 2015-16 to 2018-19 in a Tertiary Center in Western Saudi Arabia.

INTRODUCTION: Influenza infection poses a significant public health threat. The core for disease prevention and control relies on strengthened surveillance activities, particularly in Saudi Arabia, the country that hosts the largest annual mass gathering event worldwide. This study aimed to assess the molecular and seasonal pattern of influenza virus subtypes in western Saudi Arabia to inform policy decisions on influenza vaccine. METHODS: This cross-sectional study was conducted at King Abdulaziz Medical City, western Saudi Arabia. Medical records and surveillance database of laboratory-confirmed influenza cases were reviewed from October 2015 to 2019. A panel of real-time polymerase chain reactions was performed to detect influenza A and B. Extracted RNA from a subset of positive samples was used to determine influenza A subtypes and influenza B lineages. RESULTS: This study included a total of 1928 patients with laboratory-confirmed influenza infections. Influenza peaks were observed in October each season, with variant predominant strains. Influenza virus subtypes co-circulate with no reports of co-infection. Influenza A(H3N2) was reported in 42% of the cases, then influenza B (30.7%) and influenza A(H1N1)pdm09 (27.3%). Healthcare workers represented 9.4% of the cases. One-third of the cases (30.4%) were admitted to the hospital with a median admission duration of 4 days. The influenza B viruses were subtyped in 218 cases. Victoria lineage was predominant (64.1%) in 2015 and 2016; however, Yamagata was predominant in the next two consecutive seasons (94.4% and 85.4%, respectively). CONCLUSION: The burden due to influenza B may be underestimated with an observed vaccine mismatch. A quadrivalent influenza vaccine is recommended to reduce the health impact associated with influenza B infections. Molecular surveillance of the influenza viruses should be enhanced continuously for a better understanding of the influenza activity and assessment of vaccine effectiveness.

Absence of detection of RSV and influenza during the COVID-19 pandemic in a Brazilian cohort: Likely role of lower transmission in the community.

BACKGROUND: Respiratory syncytial virus (RSV) and influenza are prevalent seasonal community viruses. Although not completely understood, SARS-CoV-2 may have the same means of transmission. Preventive social measures aimed at preventing SARS-CoV-2 spread could impact transmission of other respiratory viruses as well. The aim of this study is to report the detection of RSV and influenza during the period of social distancing due to COVID-19 pandemic in a heavily affected community. METHODS: Prospective study with pediatric and adult populations seeking care for COVID-19-like symptoms during the fall and winter of 2020 at two hospitals in Southern Brazil. RT-PCR tests for SARS-CoV-2, influenza A (Flu A), influenza B (Flu B) and respiratory syncytial virus (RSV) was performed for all participants. RESULTS: 1435 suspected COVID-19 participants (1137 adults, and 298 children). were included between May and August. Median age was 37.7 years (IQR = 29.6-47.7), and 4.92 years (IQR = 1.96-9.53), for the adult and child cohorts, respectively. SARS-CoV-2 was positive in 469 (32.7%) while influenza and RSV were not detected at all. CONCLUSIONS: Measures to reduce SARS-CoV-2 transmission likely exerted a huge impact in the spread of alternate respiratory pathogens. These findings contribute to the knowledge about the dynamics of virus spread. Further, it may be considered for guiding therapeutic choices for these other viruses.

Specific Detection of Influenza A and B Viruses by CRISPR-Cas12a-Based Assay.

A rapid and accurate on-site diagnostic test for pathogens including influenza viruses is critical for preventing the spread of infectious diseases. Two types of influenza virus, A and B cause seasonal flu epidemics, whereas type A can cause influenza pandemics. To specifically detect influenza A (IAV) and B (IBV) viruses, we developed a clustered, regularly interspaced, short palindromic repeats (CRISPR) and CRISPR-associated (Cas) system-based assay. By coupling reverse transcription recombinase polymerase amplification (RT-RPA) and reverse transcription loop-mediated isothermal amplification (RT-LAMP), a CRISPR-Cas12a DNA endonuclease-targeted CRISPR trans-reporter (DETECTR) detected IAV and IBV titers as low as 1 × 100 plaque forming units (PFUs) per reaction without exhibiting cross-reactivity. Only 75 to 85 min were required to detect IAV and IBV, depending on isothermal nucleic acid amplification methods, and results were verified using a lateral flow strip assay that does not require additional analytic equipment. Taken together, our findings establish RT-RPA and RT-LAMP-coupled DETECTR-based diagnostic tests for rapid, specific and high-sensitivity detection of IAV and IBV using fluorescence and lateral flow assays. The diagnostic test developed in this study can be used to distinguish IAV and IBV infections, a capability that is necessary for monitoring and preventing the spread of influenza epidemics and pandemics.

Low circulation of Influenza A and coinfection with SARS-CoV-2 among other respiratory viruses during the COVID-19 pandemic in a region of southern Brazil.

With the arrival of coronavirus disease 2019 (COVID-19) in Brazil in February 2020, several preventive measures were taken by the population aiming to avoid severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection including the use of masks, social distancing, and frequent hand washing then, these measures may have contributed to preventing infection also by other respiratory viruses. Our goal was to determine the frequencies of Influenza A and B viruses (FLUAV/FLUBV), human mastadenovirus C (HAdV-C), Enterovirus 68 (EV-68), and rhinovirus (RV) besides SARS-CoV-2 among hospitalized patients suspect of COVID-19 with cases of acute respiratory disease syndrome (ARDS) in the period of March to December 2020 and to detect possible coinfections among them. Nucleic acid detection was performed using reverse-transcription quantitative polymerase chain reaction (RT-qPCR) in respiratory samples using naso-oropharyngeal swabs and bronchoalveolar lavage. A total of 418 samples of the 987 analyzed (42.3%) were positive for SARS-CoV-2, 16 (1.62%) samples were positive for FLUAV, no sample was positive for FLUBV or EV-68, 67 (6.78%) samples were positive for HAdV-C, 55 samples were positive for RV 1/2 (26.3%) and 37 for RV 2/2 (13.6%). Coinfections were also detected, including a triple coinfection with SARS-CoV-2, FLUAV, and HAdV-C. In the present work, a very low frequency of FLUV was reported among hospitalized patients with ARDS compared to the past years, probably due to preventive measures taken to avoid COVID-19 and the high influenza vaccination coverage in the region in which this study was performed.

Epidemiology of Influenza in Fars Province, Southern Iran; a Population-Based Study (2015-2019).

BACKGROUND: Influenza is one of the most important viral diseases with high mortality and morbidity that can have a great impact on public health and economy. OBJECTIVE: To investigate the clinical and epidemiological features of influenza virus A/H1N1, A/H3N2, and B infection in Fars province, southern Iran, in 2015-2019. METHODS: In this retrospective cross-sectional study, we assessed the archived data of Syndromic Surveillance System of Iran's Health Ministry, allowed access by Communicable Diseases' Unit of Health chancellor of Shiraz University of Medical Sciences, from December 22, 2015 to September 22, 2019. The participants included all patients whose data were recorded as influenza-like illness (ILI) and severe acute respiratory infections/illness (SARI). Influenza viral infection was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR). RESULTS: Totally, 1269 patients suspected of influenza were sampled. The mean ± SD of age was 29.40 ± 26.91 years. Fever was the most common symptom (68.6%). The highest incidence was in winter (55.9%). Of 928/1269 laboratory's results which were recorded in the registry, 204 (16.08%) samples were positive and 724 (57.05%) were negative. Among 204 positive results, 191 (15.05%) were influenza type A, and 8 (0.63%) influenza type B. Among patients with definite influenza type A, 34 (2.68%) had H1N1/p subtype, 58 (4.57%) H3N2, and one (0.08%) had other subtypes; however, subtypes were not identified in 7.72% of patients. Six (3.0%) patients with confirmed influenza expired. CONCLUSION: The incidence of influenza, especially type A, in Fars province, southern Iran is considerable and requires more attention for prevention in health policy programs.

Infecção por Influenza B e doença de Kawasaki em adolescente durante a pandemia da COVID-19: relato de caso / Influenza B infection and Kawasaki disease in an adolescent during the COVID-19 pandemic: a case report

RESUMO Apresentação de um caso de infecção por Influenza B e doença de Kawasaki em adolescente ocorrido durante a pandemia da COVID-19. Adolescente asmática evoluiu com febre e síndrome gripal por 7 dias e deu entrada com quadro de insuficiência respiratória aguda, necessitando de intubação orotraqueal. Evoluiu também com instabilidade hemodinâmica respondedora ao uso de droga vasoativa. Foram introduzidas antibioticoterapia e medidas de suporte. Apresentou melhora hemodinâmica e respiratória progressiva, porém mantinha febre e alteração de provas inflamatórias. Durante internação, evoluiu com conjuntivite não purulenta bilateral, descamação de mão e pés, língua em framboesa e linfonodomegalia cervical, recebendo diagnóstico de doença de Kawasaki. Recebeu gamaglobulina e, por conta de quadro clínico refratário, foi administrado também corticoide, evoluindo afebril 24 horas após. Não apresentou alterações coronarianas. O único agente isolado foi Influenza B, mesmo realizando painel viral e investigação para COVID-19 com reação em cadeia da polimerase e sorologia. Durante internação, apresentou tromboembolismo pulmonar, e, em investigação de coagulopatias, foi diagnosticada com mutação em heterozigose de fator V de Leiden. Há uma potencial associação entre doença de Kawasaki e infecção por Influenza B ou outros vírus, como o coronavírus e, por isso, esses diagnósticos devem ser investigados nos pacientes pediátricos, incluindo adolescentes, com quadros febris prolongados.

ABSTRACT We report a case of Influenza B infection and Kawasaki disease in an adolescent, diagnosed during the COVID-19 pandemic. An asthmatic female adolescent presented with fever and flu-like symptoms for 7 days and was admitted with acute respiratory failure requiring mechanical ventilation. She progressed with hemodynamic instability responsive to vasoactive drugs. Antibiotic therapy and support measures were introduced, showing progressive hemodynamics and respiratory improvement, however with persistent fever and increased inflammatory markers. During the hospitalization, she developed bilateral non-purulent conjunctivitis, hand and feet desquamation, strawberry tongue, and cervical adenopathy, and was diagnosed with Kawasaki disease. She was prescribed intravenous immunoglobulin and, due to the refractory clinical conditions, corticosteroid therapy was added; 24 hours later, the patient was afebrile. No coronary changes were found. A full viral panel including COVID-19 C-reactive protein and serology could only isolate the Influenza B virus. During the hospitalization, she was diagnosed with pulmonary thromboembolism; coagulopathies were investigated, and she was diagnosed with heterozygous factor V Leiden mutation. There is a potential association between Kawasaki disease and infection with Influenza B or with other viruses such as coronavirus. Therefore, this association should be considered in pediatric patients, adolescents included, with prolonged febrile conditions.

Seasonality of distinct respiratory viruses in a tropical city: implications for prophylaxis.

OBJECTIVE: The frequency and seasonality of viruses in tropical regions are scarcely reported. We estimated the frequency of seven respiratory viruses and assessed seasonality of respiratory syncytial virus (RSV) and influenza viruses in a tropical city. METHODS: Children (age ≤ 18 years) with acute respiratory infection were investigated in Salvador, Brazil, between July 2014 and June 2017. Respiratory viruses were searched by direct immunofluorescence and real-time polymerase chain reaction for detection of RSV, influenza A virus, influenza B virus, adenovirus (ADV) and parainfluenza viruses (PIV) 1, 2 and 3. Seasonal distribution was evaluated by Prais-Winsten regression. Due to similar distribution, influenza A and influenza B viruses were grouped to analyse seasonality. RESULTS: The study group comprised 387 cases whose median (IQR) age was 26.4 (10.5-50.1) months. Respiratory viruses were detected in 106 (27.4%) cases. RSV (n = 76; 19.6%), influenza A virus (n = 11; 2.8%), influenza B virus (n = 7; 1.8%), ADV (n = 5; 1.3%), PIV 1 (n = 5; 1.3%), PIV 3 (n = 3; 0.8%) and PIV 2 (n = 1; 0.3%) were identified. Monthly count of RSV cases demonstrated seasonal distribution (b3 = 0.626; P = 0.003). More than half (42/76 [55.3%]) of all RSV cases were detected from April to June. Monthly count of influenza cases also showed seasonal distribution (b3 = -0.264; P = 0.032). Influenza cases peaked from November to January with 44.4% (8/18) of all influenza cases. CONCLUSIONS: RSV was the most frequently detected virus. RSV and influenza viruses showed seasonal distribution. These data may be useful to plan the best time to carry out prophylaxis and to increase the number of hospital beds.

Epidemiological and clinical profile between influenza A and B virus in Costa Rican children.

OBJECTIVE: We aimed to evaluate the clinical and epidemiological behavior of influenza type A versus type B and analyze if there was any correlation or differences between the characteristics of both groups. METHODS: An observational, retrospective, descriptive, and population-based study based of children who were hospitalized at the only national pediatric hospital of Costa Rica from January 1, 2010 to December 31, 2018 and had a confirmed influenza virus infection. RESULTS: 336 patients were analyzed. Mean age was 35,6 ± 36,7 months (3,0 ± 3,1 years). The only significant variables at 25% in relation to influenza type A or B virus were: sex, month of diagnosis, fever, vomiting, cough, use of antibiotics and admission to the PICU. The hospitalization rate at our hospital increased between the months of October to December, with a higher percentage of cases in November and December, which reveals that the "real peak" in our population begins between 3 to 4 months after the end of the vaccination campaign. Patients with influenza A virus had a 2.5 times greater risk of being admitted to the PICU. Mortality rate was 0.6% and 0% among influenza A and B children, respectively. CONCLUSIONS: Variables in which a causality was found with type A or B virus were: admission to the PICU, month of diagnosis, and cough. However, influenza B clinical behavior continues to be unpredictable.