Epidemiological and clinical characteristics of hospitalized human metapneumovirus patients in Israel, 2015-2021: A retrospective cohort study.

This study evaluated the epidemiological and clinical characteristics of human metapneumovirus (hMPV) infection among hospitalized patients with acute respiratory infections during 2015-2021 and assessed the impact of the coronavirus disease 2019 pandemic on hMPV infection. A single-center, retrospective cohort study was performed, including pediatric and adult patients with laboratory-confirmed hMPV. Of a total of 990 patients, 253 (25.6%), 105 (10.6%), 121 (12.2%), and 511 (51.6%) belonged to age groups 0-2, 3-17, 18-59, and ≥60 years, respectively. The highest percentage (23.0%) of patients were hospitalized during 2019 and the lowest (4.7%) during 2020. Patients < 18 years experienced high rates of comorbidities (immunodeficiencies: 14.4% and malignancies: 29.9%). Here, 37/39 (94.9%) of all bronchiolitis cases were diagnosed in patients < 2 years, whereas more patients in older age groups were diagnosed with pneumonia. A greater proportion of hMPV patients diagnosed with viral coinfection (mostly respiratory syncytial virus and adenovirus) were <18 years. The highest percentages of intensive care unit admissions were recorded among patients < 18 years. Our findings demonstrate that hMPV is an important cause of morbidity in young children and a possibly underestimated cause of morbidity among older adults.

Prevalence of Parainfluenza Viruses in Seoul, 2021 - 2022.

BACKGROUND: Parainfluenza virus (PIV) is a significant etiological agent of acute lower respiratory tract infections (ALRIs) in infants and young children. The present study has been conducted to investigate the prevalence of recently identified respiratory viruses. METHODS: In total, 543 oropharyngeal or nasopharyngeal swab samples collected from hospitalized patients with acute respiratory symptoms (ARS) between January and December 2021 (5,653 females and 4,950 males) were tested for respiratory viruses using RT-PCR. RESULTS: At least one respiratory virus was detected by RT-PCR in 119 out of 175 samples (68%). The most frequently detected virus was human rhinovirus (HRV) (34, 6.5%), followed by human parainfluenza viruses (HPIVs) (19, 3.6%), human bocavirus (HBoV) (8, 1.5%), human adenovirus (HAdV) (7, 1.3%), and human respiratory syncytial virus (HRSV) (4, 0.8%). HPIV-3 accounted for 3.6% (19/175) of all viral pathogens and was the second most frequently detected viral pathogen in our study. HPIV-3 infections peaked in the fall (November) of 2021. Phylogenetic analysis of the coding region of the viral protein HA revealed that all 35 (100%) of 35 HPIV-infected patients were infected with HPIV-3. CONCLUSIONS: HPIV was an important causative pathogen associated with ALRI in children hospitalized in Korea in the late fall of 2021, as the social distancing rules for COVID-19 were relaxed. These findings highlight the im-portance of HPIV as a cause of ALRI.

Severe Human Parainfluenza Virus Community- and Healthcare-Acquired Pneumonia in Adults at Tertiary Hospital, Seoul, South Korea, 2010-2019.

The characteristics of severe human parainfluenza virus (HPIV)-associated pneumonia in adults have not been well evaluated. We investigated epidemiologic and clinical characteristics of 143 patients with severe HPIV-associated pneumonia during 2010-2019. HPIV was the most common cause (25.2%) of severe virus-associated hospital-acquired pneumonia and the third most common cause (15.7%) of severe virus-associated community-acquired pneumonia. Hematologic malignancy (35.0%), diabetes mellitus (23.8%), and structural lung disease (21.0%) were common underlying conditions. Co-infections occurred in 54.5% of patients admitted to an intensive care unit. The 90-day mortality rate for HPIV-associated pneumonia was comparable to that for severe influenza virus-associated pneumonia (55.2% vs. 48.4%; p = 0.22). Ribavirin treatment was not associated with lower mortality rates. Fungal co-infections were associated with 82.4% of deaths. Clinicians should consider the possibility of pathogenic co-infections in patients with HPIV-associated pneumonia. Contact precautions and environmental cleaning are crucial to prevent HPIV transmission in hospital settings.

Patterns of Non-influenza Respiratory Viruses Among Severe Acute Respiratory Infection Cases in Burkina Faso: A Surveillance Study.

BACKGROUND: Although influenza viruses cause only one-fifth of severe acute respiratory infections (SARI) in Burkina Faso, the other viral causes of SARI remain poorly investigated to inform clinical and preventive decision making. METHODS: Between 2016 and 2019, we prospectively enrolled inpatients meeting the World Health Organization (WHO) case definition of SARI in Burkina Faso. Results of viral etiologies among inpatients tested negative for influenza using the Fast Track Diagnostics Respiratory Kits (FTD-33) were reported. RESULTS: Of 1541 specimens tested, at least one respiratory virus was detected in 76.1% of the 1231 specimens negative for influenza virus. Human rhinoviruses (hRVs) were the most detected pathogens (476; 38.7%), followed by human adenoviruses (hAdV) (17.1%, 210/1231), human respiratory syncytial virus (hRSV) (15.4%, 189/1231), enterovirus (EnV) (11.2%, 138/1231), human bocavirus (hBoV) (7.9%, 97/1231), parainfluenza 3 (hPIV3) (6.1%, 75/1231), human metapneumovirus (hMPV) (6.0%,74/1321), parainfluenza 4 (hPIV4) (4.1%, 51/1231), human coronavirus OC43 (hCoV-OC43) (3.4%, 42/1231), human coronavirus HKU1(hCoV-HKU1) (2.7%, 33/1231), human coronavirus NL63 (hCoV-NL63) (2.5%, 31/1231), parainfluenza 1 (hPIV1) (2.0%, 25/1231), parainfluenza 2 (hPIV2) (1.8%, 22/1231), human parechovirus (PeV) (1.1%, 14/1231), and human coronavirus 229E (hCoV-229E) (0.9%, 11/1231). Among SARI cases, infants aged 1-4 years were mostly affected (50.7%; 622/1231), followed by those <1 year of age (35.7%; 438/1231). Most detected pathogens had year-long circulation patterns, with seasonal peaks mainly observed during the cold and dry seasons. CONCLUSION: Several non-influenza viruses are cause of SARI in Burkina Faso. The integration of the most common pathogens into the routine influenza surveillance system might be beneficial.

Changes in Viral Dynamics Following the Legal Relaxation of COVID-19 Mitigation Measures in Japan From Children to Adults: A Single Center Study, 2020-2023.

INTRODUCTION: Respiratory infections are an ongoing global health challenge. The COVID-19 pandemic triggered global nonpharmacological measures that reshaped public health. In Japan, the shift from legal to individual discretion in pandemic management started on May 8, 2023. However, it still unknown how the relaxation of measures affects respiratory pathogens across age groups. METHODS: We collected 16,946 samples from 13,526 patients between February 2020 and September 2023, analyzing the circulating respiratory pathogen dynamics using FilmArray respiratory panel. RESULTS: Our analysis revealed significant increases in the positivity rates of respiratory pathogens across multiple age groups after relaxation. The pathogens including adenovirus, Bordetella pertussis, parainfluenza 2 and parainfluenza 4 showed increased positivity predominantly in children aged under 10 years. Conversely, some pathogens including human metapneumovirus, rhinovirus/enterovirus, and respiratory virus (RSV) increased in broad range of age groups. SARS-CoV-2 positivity rates decreased in children under 10 years but increased in those aged over 60 years. DISCUSSION: Age-stratified analysis reveals a dynamic pattern of circulating pathogen in each age group after relaxation measures. This study provides essential epidemiologic data that can guide strategies to protect different age groups and effectively respond to respiratory infections in post-COVID-19 era.

Upper and/or Lower Respiratory Tract Infection Caused by Human Metapneumovirus After Allogeneic Hematopoietic Stem Cell Transplantation.

BACKGROUND: Human metapneumovirus (hMPV) epidemiology, clinical characteristics and risk factors for poor outcome after allogeneic stem cell transplantation (allo-HCT) remain a poorly investigated area. METHODS: This retrospective multicenter cohort study examined the epidemiology, clinical characteristics, and risk factors for poor outcomes associated with human metapneumovirus (hMPV) infections in recipients of allo-HCT. RESULTS: We included 428 allo-HCT recipients who developed 438 hMPV infection episodes between January 2012 and January 2019. Most recipients were adults (93%). hMPV infections were diagnosed at a median of 373 days after allo-HCT. The infections were categorized as upper respiratory tract disease (URTD) or lower respiratory tract disease (LRTD), with 60% and 40% of cases, respectively. Patients with hMPV LRTD experienced the infection earlier in the transplant course and had higher rates of lymphopenia, neutropenia, corticosteroid use, and ribavirin therapy. Multivariate analysis identified lymphopenia and corticosteroid use (>30 mg/d) as independent risk factors for LRTD occurrence. The overall mortality at day 30 after hMPV detection was 2% for URTD, 12% for possible LRTD, and 21% for proven LRTD. Lymphopenia was the only independent risk factor associated with day 30 mortality in LRTD cases. CONCLUSIONS: These findings highlight the significance of lymphopenia and corticosteroid use in the development and severity of hMPV infections after allo-HCT, with lymphopenia being a predictor of higher mortality in LRTD cases.

Alterations in Patients' Clinical Outcomes and Respiratory Viral Pathogen Activity following the COVID-19 Pandemic.

BACKGROUND: Before the COVID-19 pandemic, respiratory pathogens such as influenza, parainfluenza, and respiratory syncytial virus were the most commonly detected viruses among hospitalized patients with respiratory tract infections. METHODS: This was a retrospective observational study of inpatients and outpatients who attended Jordan University Hospital and underwent Nasopharyngeal Aspiration (NPA) in the periods from December 2017 to December 2018 and from December 2021 to December 2022. The results of multiplex respiratory pathogen real-time PCR tests for nasopharyngeal swab specimens were extracted from the electronic-based molecular diagnostic laboratory record of JUH. We compared the prevalence of the detected viruses as well as the patients' characteristics and outcomes between the two periods. RESULTS: The total number of included patients was 695. Our analysis showed that a higher percentage of patients with hypertension and diabetes presented before the pandemic compared to the same period after it (p-value < 0.001). The need for O2 devices, white blood cell counts, diastolic blood pressure, and the length of hospital stay were significantly higher among patients who presented before the pandemic (p-value < 0.050). Influenza H1N1 (8.70% vs. 4.03%), influenza B (1.67% vs. 0.25%), parainfluenza (1.00% vs. 0.00%), human metapneumovirus (5.35% vs. 0.76%), adenoviruses (6.35% vs. 3.02%), and coronaviruses (8.70% vs. 3.53%) were detected with higher frequency in the period before the pandemic (p-value = 0.011, 0.045, 0.045, 0.000, 0.035, 0.004). These results were similar in terms of changes in the detection rates of viruses after matching the number of tested patients between the periods before and after the pandemic. CONCLUSIONS: We have demonstrated a reduction in the detection of several viruses, which might be due to the increase in public awareness toward infection protection measures after the COVID-19 pandemic.

Profile analysis of emerging respiratory virus in children.

Acute respiratory infections (ARIs) are caused by a variety of microorganisms. Of all ARIs, 80% are caused by viruses such as human respiratory syncytial virus, metapneumovirus, influenza, parainfluenza, rhinovirus, and, more recently, Sars-CoV-2, which has been responsible for the COVID-19 pandemic. The objective of our study was to evaluate clinical data from a viral panel performed in children hospitalized with SARS or COVID-19 in the infirmary or ICU of 5 pediatric hospitals in the city of Goiânia, Goiás, Brazil. Demographic, clinical, and laboratory data were collected for analysis, and data on the outcomes underwent statistical treatment. A total of 128 patients were selected for the study, 54% of whom were male and 46% female. The viral panel included rhinovirus, COVID-19, metapneumovirus, adenovirus, and parainfluenza. Descriptive analyses of age profile showed differences in the involvement of particular viruses. The percentage of patients who required hospitalization in the ICU, infirmary, as well as individuals who were discharged after therapy or who died, were described. Our work shows that epidemiological surveillance measures are indispensable, especially if used in the continued analysis of viral panels in all pediatric patients with SARS.

Outbreak of Parainfluenza Virus During the COVID-19 Pandemic at a University Hospital in Korea.

BACKGROUND: The incidence of respiratory viral diseases including parainfluenza virus (PIV) infection has decreased noticeably due to strict quarantine measures during the COVID-19 pandemic. However, the recent outbreak of PIV in children occurred unexpectedly and the distribution pattern showed prominent differences from before the COVID-19 pandemic. PIV is one of the major viral pathogens related to acute lower respiratory infection in young children and the elderly. Accordingly, the authors intended to identify the incidence and distribution pattern of PIV outbreaks and to contribute to public health by providing information on it. METHODS: This study was conducted retrospectively to investigate the incidence and distribution of PIV according to age group, gender, month, and season, and to analyze the co-infections from March 2020 to February 2022. The detection for respiratory microorganisms was performed through FilmArray assay. RESULTS: The overall incidence for at least one respiratory pathogen was 45.9% (665/1,450). PIV was not detected at all from March 2020 to August 2021. However, it was first detected in September 2021 and the rate in the month that followed, October, accounted for 60% (114/190) of the total PIV infections during the entire study period. It also accounted for 44.9% (190/423) of patients with respiratory pathogens from September 2021 to February 2022. It reached the highest proportion at 90.5% (114/126) in October 2021. As for the distribution according to the age groups, group 3 (58.4%) accounted for the highest percentage, followed by group 4 (21.1%). In the PIV positive cases, the overall rate of more than two respiratory pathogens was 32.6% (62/190). The most common pattern of co-infection was PIV3 with rhinovirus/enterovirus (67.7%), followed by PIV3 with adenovirus (8.1%) and PIV3 with rhinovirus/enterovirus and adenovirus (8.1%). CONCLUSIONS: The COVID-19 pandemic has brought about many changes in our daily lives. It has been confirmed that the seasonal distribution of PIV was distinctly different from before the COVID-19 pandemic. It is anticipated that this phenomenon will affect the incidence or distribution of other respiratory pathogens and viral epidemiology. Therefore, clinicians should pay attention to these changes in terms of public health.

Prospective Surveillance of Respiratory Infections in British Antarctic Survey Bases During the COVID-19 Pandemic.

BACKGROUND: The British Antarctic bases offer a semiclosed environment for assessing the transmission and persistence of seasonal respiratory viruses. METHODS: Weekly swabbing was performed for respiratory pathogen surveillance (including SARS-CoV-2), at 2 British Antarctic Survey bases, during 2020: King Edward Point (KEP, 30 June to 29 September, 9 participants, 124 swabs) and Rothera (9 May to 6 June, 27 participants, 127 swabs). Symptom questionnaires were collected for any newly symptomatic cases that presented during this weekly swabbing period. RESULTS: At KEP, swabs tested positive for non-SARS-CoV-2 seasonal coronavirus (2), adenovirus (1), parainfluenza 3 (1), and respiratory syncytial virus B (1). At Rothera, swabs tested positive for non-SARS-CoV-2 seasonal coronavirus (3), adenovirus (2), parainfluenza 4 (1), and human metapneumovirus (1). All bacterial agents identified were considered to be colonizers and not pathogenic. CONCLUSIONS: At KEP, the timeline indicated that the parainfluenza 3 and adenovirus infections could have been linked to some of the symptomatic cases that presented. For the other viruses, the only other possible sources were the visiting ship crew members. At Rothera, the single symptomatic case presented too early for this to be linked to the subsequent viral detections, and the only other possible source could have been a single nonparticipating staff member.

Population-based hospitalization burden estimates for respiratory viruses, 2015-2019.

BACKGROUND: Acute respiratory infections (ARIs) result in millions of illnesses and hundreds of thousands of hospitalizations annually in the United States. The responsible viruses include influenza, parainfluenza, human metapneumovirus, coronaviruses, respiratory syncytial virus (RSV), and human rhinoviruses. This study estimated the population-based hospitalization burden of those respiratory viruses (RVs) over 4 years, from July 1, 2015 to June 30, 2019, among adults ≥18 years of age for Allegheny County (Pittsburgh), Pennsylvania. METHODS: We used population-based statewide hospital discharge data, health system electronic medical record (EMR) data for RV tests, census data, and a published method to calculate burden. RESULTS: Among 26,211 eligible RV tests, 67.6% were negative for any virus. The viruses detected were rhinovirus/enterovirus (2552; 30.1%), influenza A (2,299; 27.1%), RSV (1082; 12.7%), human metapneumovirus (832; 9.8%), parainfluenza (601; 7.1%), influenza B (565; 6.7%), non-SARS-CoV-2 coronavirus (420; 4.9% 1.5 years of data available), and adenovirus (136; 1.6%). Most tests were among female (58%) and White (71%) patients with 60% of patients ≥65 years, 24% 50-64 years, and 16% 18-49 years. The annual burden ranged from 137-174/100,000 population for rhinovirus/enterovirus; 99-182/100,000 for influenza A; and 56-81/100,000 for RSV. Among adults <65 years, rhinovirus/enterovirus hospitalization burden was higher than influenza A; whereas the reverse was true for adults ≥65 years. RV hospitalization burden increased with increasing age. CONCLUSIONS: These virus-specific ARI population-based hospital burden estimates showed significant non-influenza burden. These estimates can serve as the basis for several areas of research that are essential for setting funding priorities and guiding public health policy.

Epidemiology and genetic characterization of human metapneumovirus in pediatric patients from Hangzhou China.

Human metapneumovirus (HMPV), which is distributed worldwide, is a significant viral respiratory pathogen responsible for causing acute respiratory tract infections (ARTIs) in children. The aim of the present study was to investigate the epidemiological and genetic characteristics of HMPV in pediatric patients in Hangzhou China following the peak of onset of coronavirus disease 2019 (COVID-19). A total of 1442 throat swabs were collected from the pediatric patients with a diagnosis of ARTI from November 2020 to March 2021. The following viruses were detected by real-time polymerase chain reaction analysis: HMPV, RSV, adenovirus, hPIV1-3, influenza A, and influenza B. A two-step method was used to amplify the F genes of the HMPV-positive samples. Following sequencing, phylogenetic analyses were conducted using the MEGA version 7 software package. Among the 1442 samples, 103 (7.14%) were positive for HMPV. No significant differences were observed in the gender distribution. The highest incidence of HMPV occurred in children older than 6 years and the lowest was noted in children younger than 6 months. Lower respiratory tract infections were diagnosed at a higher rate than upper respiratory tract infections in HMPV-infected children. Only 10 HMPV-infected children (5.41%) were inpatients compared with 93 outpatients (7.39%). Co-infection was observed in 31 HMPV-positive samples including 24 samples of double infection and seven samples of triple infection. A total of 61F gene fragments of HMPV, which were approximately 727 bp in length were successfully sequenced. All the HMPVs belonged to the genotype B and were clustered into subgenotypes B1 (1.6%, 1/61) and B2 (98.4%, 60/61). A total of four specific amino acid substitutions were noted as follows: aa280, aa296, aa392, and aa396. These substitutions were present between sequences derived from the subgenotypes B1 and B2 in the fusion open reading frame from position 244 to 429. In conclusion, the present study provided significant information regarding the epidemiological and genetic characteristics of HMPV in children living in Hangzhou. Following the first peak of the COVID-19 pandemic, HMPV was considered an important viral respiratory pathogen present in children with ARTI.

Controlling a human parainfluenza virus-3 outbreak in a haematology ward in a tertiary hospital: the importance of screening strategy and molecular diagnostics in relation to clinical symptoms.

BACKGROUND: The human parainfluenza virus 3 (HPIV-3) outbreak at the haemato-oncology ward of the Maastricht University Medical Centre in the summer of 2016. AIM: To describe an effective strategy to control the largest reported HPIV-3 outbreak at an adult haematology-oncology ward in the Netherlands by implementing infection control measures and molecular epidemiology investigation. METHODS: Clinical, patient and diagnostic data were both pro- and retrospectively collected. HPIV-3 real-time polymerase chain reaction (HPIV-3 RT-PCR) was validated using oropharyngeal rinse samples. Screening of all new and admitted patients was implemented to identify asymptomatic infection or prolonged shedding of HPIV-3 allowing cohort isolation. FINDINGS: The HPIV-3 outbreak occurred between 9 July and 28 September 2016 and affected 53 patients. HPIV-3 RT-PCR on oropharyngeal rinse samples demonstrated an up to 10-fold higher sensitivity compared with pharyngeal swabs. Monitoring showed that at first positive PCR, 20 patients (38%) were asymptomatic (of which 11 remained asymptomatic) and the average duration of shedding was 14 days (range 1-58). Asymptomatic patients had lower viral load, shorter period of viral shedding (≤14 days) and were mostly immune-competent oncology patients. The outbreak was under control five weeks after implementation of screening of asymptomatic patients. CONCLUSION: Implementation of a sensitive screening method identified both symptomatic and asymptomatic patients which had lower viral loads and allowed early cohort isolation. This is especially important in a ward that combines patients with varying immune status, because both immunocompromised and immune-competent patients are likely to spread the HPIV-3 virus, either through prolonged shedding or through asymptomatic course of disease.

Record high parainfluenza season in children after relaxation of COVID-19 restrictions in fall 2021-A nationwide register study in Finland.

Social restrictions interrupted the circulation of common respiratory viruses among children in spring 2020. In the winter season 2020-2021, only rhinovirus spread in Finland. As the restrictions were ended in September 2021, we saw record high epidemic peak of parainfluenza. Typically, the epidemic peak is in springtime, but now, it started in the early fall 2021. The monthly incidence among children aged 0-4 years (120 per 100,000 children) was six times higher than the second highest reported monthly incidence (21 per 100,000 children) during the last 10 years. Our finding highlights the importance of active surveillance of viral respiratory pathogens during the pandemic.

The epidemiological features of pediatric viral respiratory infection during the COVID-19 pandemic in Taiwan.

BACKGROUND: Enhanced nonpharmaceutical interventions (NPIs) to prevent the Coronavirus Disease 2019 (COVID-19) have shown various levels of impact on common respiratory pathogens. We aimed to analyze the epidemiological changes seen in certain common respiratory viruses found in Taiwanese children (e.g., influenza virus, enterovirus, parainfluenza virus, adenovirus and respiratory syncytial virus (RSV)) after the implementation of public health measures, as well as interpret the possible meaning of these changes. METHODS: This retrospective observational study examined the viral isolation from children younger than 18 years at a medical center in central Taiwan during the period January 2015-December 2020, a time frame of six years. Viral isolations prior to the COVID-19 pandemic (January 2015-December 2019), along with those during the post-COVID-19 period (January-December 2020) were analyzed and compared. RESULTS: A total of 6899 throat swab samples were collected during the pre-pandemic period of 2015-2019, with 2681 of them having a positive result (38.86%). There were a total of 713 samples collected in 2020, with 142 of them showing positive results (19.92%). The overall positive rate of viral isolates significantly decreased in 2020 (p < 0.001). Declines in the isolation of the influenza virus, parainfluenza virus, adenovirus and enterovirus were observed. The RSV surprisingly became the leading isolate, with up to 47 (6.59%) instances in 2020, and showing an unusual peak in the winter of 2020. The rise began in September of 2020 and reached its plateau in November of that year. CONCLUSIONS: Most respiratory viruses decreased under NPIs regarding SARS-CoV-2. However, the RSV outbreak in the winter of 2020 had shown the limitation of current NPIs. Possible explanations have been discussed in details and public preventive measures should be reinforced for RSV, particularly amongst people having young children both at home and in care centers.

Predictors of Hospitalization and Superinfection in Viral Respiratory Tract Infections Between Influenza and Paramyxoviruses: The SUPERFLUOUS Study.

BACKGROUND: Viral respiratory tract infections (VRTIs) are among the most common diseases, but the risks of superinfection for different virus species have never been compared. METHODS: Multicenter retrospective study conducted among adults who tested positive for VRTIs with reverse-transcription polymerase chain reaction. We compared characteristics between influenza (A or B) and paramyxoviruses (respiratory syncytial virus, parainfluenza virus types 1 and 3, and human metapneumovirus) and identified predictors of superinfection and hospitalization.s. RESULTS: Five hundred ninety patients had VRTI, including 347 (59%) influenza and 243 paramyxovirus infections with comparable rates of superinfections (53% vs 60%). In multivariate analyses, the predictors of superinfections were age >75 years (adjusted odds ratio, 2.37 [95% confidence interval, 1.65-3.40]), chronic respiratory disease (1.79 [1.20-2.67]), and biological abnormalities, including neutrophil count >7000/µL (1.98 [1.34-2.91)], eosinophil count <50/µL (2.53 [1.61-3.98], and procalcitonin level >0.25ng/mL (2.8 [1.65-4.73]). The predictors of hospitalization were age >75 years old (adjusted odds ratio, 3.49 [95% confidence interval, 2.17-5.63]), paramyxovirus infection (2.28 [1.39-3.75]), long-term use of inhaled corticosteroids (2.49 [1.13-5.49]), and biological abnormalities, including neutrophil count >7000/µL (2.38 [1.37-4.12)] and procalcitonin level >0.25ng/mL (2.49 [1.23-5.02]). Kaplan-Meier survival curves showed that influenza-infected patients had a higher mortality rate than those with paramyxovirus infections (8.9% vs 4.5%, respectively; P = .02). CONCLUSIONS: Our study revealed a high rate of superinfection (56%), not related to viral species. However influenza virus was associated with a poorer prognosis than paramyxoviruses, pleading for a broader and large-scale vaccination of individual at risk of VRTIs.

Epidemiology and factors associated with the severity of viral acute lower respiratory infection in children hospitalized in Manaus, Amazonas, in 2017-2018: An observational study.

ABSTRACT: To investigate the epidemiology and factors associated with the severity of viral acute lower respiratory infection (ALRI) in children hospitalized in Manaus, Amazonas, in 2017 to 2018.Retrospective cohort study of children hospitalized at the Hospital and Emergency Room Delphina Rinaldi Abdel Aziz, in Manaus, from April 01, 2017 to August 31, 2018, with a clinical diagnosis of ALRI and nasopharyngeal aspirates positive for at least 1 respiratory virus.One hundred forty-six children aged 0.2 to 66 months (median 7 months) were included. Patients were divided into 2 groups according to the disease severity classified by an adapted Walsh et al score: moderate disease, score 0-4, n = 66 (45.2%) and severe disease, score 5-7, n = 80 (54.8%). A greater number of viral ALRI cases were observed in the rainiest months. Respiratory syncytial virus was the most prevalent (n = 103, 70.3%), followed by metapneumovirus (n = 24, 16.4%), influenza virus (n = 17, 11.6%), parainfluenza virus (n = 11, 7.5%), and adenovirus (n = 4, 2.7%). Co-detections of 2 to 3 viruses were found in 12 (8.2%) patients. The presence of viral coinfection was an independent risk factor for disease severity (adjusted relative risk [RR] 1.53; 95% CI 1.10-2.14). Twelve patients (8.2%) died, all with severe disease. Risk factors for death were shock (adjusted RR 10.09; 95% CI 2.31-43.90) and need for vasoactive drugs (adjusted RR 10.63; 95% CI 2.44-46.31).There was a higher incidence of viral ALRI in Manaus in the rainy season. Respiratory syncytial virus was the most prevalent virus. The presence of viral coinfection was an independent risk factor for disease severity.

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.

Characteristics of human metapneumovirus infection in adults hospitalized for community-acquired influenza-like illness in France, 2012-2018: a retrospective observational study.

OBJECTIVES: To describe the prevalence, clinical features and complications of human metapneumovirus (hMPV) infections in a population of adults hospitalized with influenza-like illness (ILI). METHODS: This was a retrospective, observational, multicenter cohort study using prospectively collected data from adult patients hospitalized during influenza virus circulation, for at least 24 h, for community-acquired ILI (with symptom onset <7 days). Data were collected from five French teaching hospitals over six consecutive winters (2012-2018). Respiratory viruses were identified by multiplex reverse transcription polymerase chain reaction (RT-PCR) on nasopharyngeal specimens. hMPV + patients were compared with hMPV- patients, influenza+ and respiratory syncytial virus (RSV)+ patients using multivariate logistic regressions. Primary outcome was the prevalence of hMPV in patients hospitalized for ILI. RESULTS: Among the 3148 patients included (1449 (46%) women, 1988 (63%) aged 65 and over; 2508 (80%) with chronic disease), at least one respiratory virus was detected in 1604 (51%, 95% confidence interval (CI) 49-53), including 100 cases of hMPV (100/3148, 3% 95% CI 3-4), of which 10 (10%) were viral co-infection. In the hMPV + patients, mean length of stay was 7 days, 62% (56/90) developed a complication, 21% (14/68) were admitted to intensive care unit and 4% (4/90) died during hospitalization. In comparison with influenza + patients, hMPV + patients were more frequently >65 years old (adjusted odds ratio (aOR) = 3.3, 95% CI 1.9-6.3) and presented more acute heart failure during hospitalization (aOR = 1.8, 95% CI 1.0-2.9). Compared with RSV + patients, hMPV + patients had less cancer (aOR = 0.4, 95% CI 0.2-0.9) and were less likely to smoke (aOR = 0.5, 95% CI 0.2-0.9) but had similar outcomes, especially high rates of respiratory and cardiovascular complications. CONCLUSIONS: Adult hMPV infections mainly affect the elderly and patients with chronic conditions and are responsible for frequent cardiac and pulmonary complications similar to those of RSV infections. At-risk populations would benefit from the development of antivirals and vaccines targeting hMPV.