Striking absence of "usual suspects" during the winter of the coronavirus disease 2019 (COVID-19) pandemic 2020-2021

[...]other respiratory infections due to pathogens such as respiratory syncytial (RSV) and rhinovirus are very common during flu season.1,2 Respiratory viral activity typically peaks in December and January, but the flu season can last until May.1 Many individuals receive the influenza vaccine from their primary care provider in the beginning of the fall season, and this is particularly effective in reducing the number of influenza infections.3 In 2020, however, the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) virus emerged and dramatically changed the landscape of medicine. To stop the spread of SARS-CoV-2, community mitigating factors, such as social distancing, frequent hand washing, mask mandates, and school closures, were implemented widely.4 When the COVID-19 pandemic started in March 2020, many reported that seasonal flu cases disappeared earlier than expected.5 Additionally, an overall reduction in the incidence of respiratory viral infections during the flu season was noted on both national and international levels. Additionally, data from 42 medical centers in the Midwest region of the United States that utilize the Biofire system respiratory viral panel were obtained and analyzed.7,8 In the same study period of September 2020–February 2021, there were far fewer positive tests of influenza A and B, RSV, parainfluenza, coronaviruses, and human metapneumovirus compared to the prior flu season.