Remote household observation for non-influenza respiratory viral illness

Emanuels A, Heimonen J, O'Hanlon J, Kim AE, Wilcox N, McCulloch DJ, Brandstetter E, Wolf CR, Logue JK, Han PD, Pfau B, Newman KL, Hughes JP, Jackson ML, Uyeki TM, Boeckh M, Starita LM, Nickerson DA, Bedford T, Englund JA, Chu HY, on behalf of Seattle Flu Study investigators. 2020. Clin Infect Dis: ciaa1719.


Background. Non-influenza respiratory viruses are responsible for a substantial burden of disease in the United States. Household transmission is thought to contribute significantly to subsequent transmission through the broader community. In the context of the COVID-19 pandemic, contactless surveillance methods are of particular importance.

Methods. From November 2019 to April 2020, 303 households in the Seattle area were remotely monitored in a prospective longitudinal study for symptoms of respiratory viral illness. Enrolled participants reported weekly symptoms and submitted respiratory samples by mail in the event of an acute respiratory illness (ARI). Specimens were tested for fourteen viruses, including SARS-CoV-2, using RT-PCR. Participants completed all study procedures at home without physical contact with research staff.

Results. In total, 1171 unique participants in 303 households were monitored for ARI. Of participating households, 128 (42%) included a child aged <5 years and 202 (67%) included a child aged 5-12 years. Of the 678 swabs collected during the surveillance period, 237 (35%) tested positive for one or more non-influenza respiratory viruses. Rhinovirus, common human coronaviruses, and respiratory syncytial virus were the most common. Four cases of SARS-CoV-2 were detected in three households.

Conclusions. This study highlights the circulation of respiratory viruses within households during the winter months during the emergence of the SARS-CoV-2 pandemic. Contactless methods of recruitment, enrollment and sample collection were utilized throughout this study, and demonstrate the feasibility of home-based, remote monitoring for respiratory infections.