Prevalence of co-infections with respiratory viruses in individuals
investigated for SARS-CoV-2 in Ontario, Canada
Background: Co-infections of SARS-CoV-2 with respiratory viruses,
bacteria and fungi have been reported to cause a wide range of illness.
Objectives: We assess the prevalence of co-infection of SARS-CoV-2 with
seasonal respiratory viruses, document the respiratory viruses detected
among individuals tested for SARS-CoV-2, and describe characteristics of
individuals with respiratory virus co-infection detected. Methods:
Specimens included in this study were submitted as part of routine
clinical testing to Public Health Ontario Laboratory from individuals
requiring testing for SARS-CoV-2 and/or seasonal respiratory viruses.
Results: Co-infection was detected in a smaller proportion (2.5%) of
individuals with laboratory confirmed SARS-CoV-2 than those with
seasonal respiratory viruses (4.3%); this difference was not
significant. Individuals with any respiratory virus co-infection were
more likely to be younger than 65 years of age and male than those with
single respiratory virus infection. Those with SARS-CoV-2 co-infection
manifested mostly mild respiratory symptoms. Conclusions: Findings of
this study may not support routine testing for seasonal respiratory
viruses among all individuals tested for SARS-CoV-2, as they were rare
during the study period nor associated with severe disease. However,
testing for seasonal respiratory viruses should be performed in severely
ill individuals, in which detection of other respiratory viruses may
assist with patient management.