ABSTRACT
Background. Adenovirus (AdV) is a common cause of acute respiratory illness (ARI). Multiple respiratory AdV types have been identified in humans, but it remains unclear which are the most common in U.S. children with ARI. Methods. We conducted a multicenter, prospective viral surveillance study at seven U.S. children's hospitals, the New Vaccine Surveillance Network, during 12/1/ 16-11/30/19, prior to the COVID-19 pandemic. Children < 18 years of age seen in the emergency department or hospitalized with fever and/or respiratory symptoms were enrolled, and mid-turbinate nasal +/- throat swabs were tested using multiplex respiratory pathogen assays or real time polymerase chain reaction (PCR) test for AdV, respiratory syncytial virus (RSV), human metapneumovirus, rhinovirus/enterovirus (RV), influenza, parainfluenza viruses, and endemic coronaviruses. AdV-positive specimens were subsequently typed using single-plex qPCR assays targeting sequences in the hexon gene specific for types 1-7, 11, 14, 16 and 21. Demographics, clinical characteristics, and outcomes were compared between AdV types. Results. Of 29,381 enrolled children, 2,106 (7.2%) tested positive for AdV. The distribution of types among the 1,330 (63.2%) successfully typed specimens were as follows: 31.7% AdV-2, 28.9% AdV-1, 15.3% AdV-3, 7.9% AdV-5, 5.9% AdV-7, 1.4% AdV-4, 1.2% AdV-6, 0.5% AdV-14, 0.2% AdV-21, 0.1% AdV-11, and 7.0% >=1 AdV type. Most children with AdV-1 or AdV-2 detection were < 5 years of age (Figure 1a). Demographic and clinical characteristics varied by AdV types, including age, race/ethnicity, smoke exposure, daycare/school attendance, and hospitalization (Table 1). Co-detection with other viruses was common among all AdV types, with RV and RSV being the most frequently co-detected (Figure 1b). Fever and cough were the most common symptoms for all AdV types (Figure 2). Children with AdV-7 detected as single pathogen had higher odds of hospitalization (adjusted odds ratio 6.34 [95% CI: 3.10, 12.95], p= 0.027). Conclusion. AdV-2 and AdV-1 were the most frequently detected AdV types among children over the 3-year study period. Notable clinical heterogeneity of the AdV types warrants further surveillance studies to identify AdV types that could be targeted for pediatric vaccine development. (Figure Presented).
ABSTRACT
Background. Prolonged infection by respiratory viruses has been reported, especially in hospitalized or immunocompromised children. However, little is known of factors contributing to prolonged respiratory viral infection, particularly in asymptomatic and less severe infections. We examined characteristics associated with prolonged viral infection in a community-based birth cohort. Methods. The PREVAIL cohort is a CDC-sponsored two-year birth cohort in Cincinnati, Ohio conducted during 4/2017 to 8/2020. Mid-turbinate nasal swabs were collected weekly from children and tested using the Luminex Respiratory Pathogen Panel. The primary outcome was prolonged viral infection, which was defined as a viral nucleic acid detection lasting 4 or more weeks. Proportions of prolonged viral infections were compared using Fisher's exact test with Holms corrections. Adjusted odds ratios (aOR) and 95% confidence intervals were calculated using a mixed effects logistic regression model while controlling for within-subject clustering, viral species, child age, child sex, symptom status, and coinfection. This analysis was limited to subjects who provided at least 70% of weekly samples. Results. Among 101 children, providing 7871 child-weeks of follow-up, we identified 780 viral infections. The median duration of infection across all respiratory viruses was 1 week, except for bocavirus and coronavirus NL63, each with 2 weeks;40% of bocavirus and >10% of adenovirus, coronavirus NL63, RSV A, human metapneumovirus, and parainfluenza 1 infections were associated with prolonged infection (>4 weeks). No prolonged infections were detected for influenza A or B, coronavirus 229E or HKU1, or parainfluenza 2 or 4 infections. Viral coinfection (aOR=3.1, 95% CI 1.9, 5.0) and female sex (aOR 1.8, 95%CI 1.1, 2.9) were significantly associated with prolonged infection, while symptom status and child age were not. Conclusion. In the PREVAIL cohort, detection of respiratory viruses lasting 4 weeks or longer was common for certain respiratory pathogens and was especially prolonged for bocavirus. Biological factors such as the presence of additional viral infections or child sex may affect the likelihood of prolonged infection. (Figure Presented).
ABSTRACT
Background. Sharp declines in influenza and respiratory syncytial virus (RSV) circulation across the U.S. have been described during the pandemic in temporal association with community mitigation for control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We aimed to determine relative frequencies of rhinovirus/ enterovirus (RV/EV) and other respiratory viruses in children presenting to emergency departments or hospitalized with acute respiratory illness (ARI) prior to and during the COVID-19 pandemic. Methods. We conducted a multi-center active prospective ARI surveillance study in children as part of the New Vaccine Surveillance Network (NVSN) from December 2016 through January 2021. Molecular testing for RV/EV, RSV, influenza, and other respiratory viruses [i.e., human metapneumovirus, parainfluenza virus (Types 1-4), and adenovirus] were performed on specimens collected from children enrolled children. Cumulative percent positivity of each virus type during March 2020-January 2021 was compared from March-January in the prior seasons (2017-2018, 2018-2019, 2019-2020) using Pearson's chi-squared. Data are provisional. Results. Among 69,403 eligible children, 37,676 (54%) were enrolled and tested for respiratory viruses. The number of both eligible and enrolled children declined in early 2020 (Figure 1), but 4,691 children (52% of eligible) were enrolled and tested during March 2020-January 2021. From March 2020-January 2021, the overall percentage of enrolled children with respiratory testing who had detectable RV/EV was similar compared to the same time period in 2017-2018 and 2019-2020 (Figure 1, Table 1). In contrast, the percent positivity of RSV, influenza, and other respiratory viruses combined declined compared to prior years, (p< 0.001, Figure 1, Table 1). Figure 1. Percentage of Viral Detection Among Enrolled Children Who Received Respiratory Testing, New Vaccine Surveillance Network (NVSN), United States, December 2016 - January 2021 Table 1. Percent of Respiratory Viruses Circulating in March 2020- January 2021, compared to March-January in Prior Years, New Vaccine Surveillance Network (NVSN), United States, March 2017 - January 2021 Conclusion. During 2020, RV/EV continued to circulate among children receiving care for ARI despite abrupt declines in other respiratory viruses within this population. These findings warrant further studies to understand virologic, behavioral, biological, and/or environmental factors associated with this continued RV/EV circulation.