Respiratory Pathogen Coinfections in SARS-CoV-2-Positive Patients in Southeastern Wisconsin: A Retrospective Analysis.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of coronavirus disease 2019 (COVID-19), has infected all age groups and disproportionately impacted vulnerable populations globally. Polymicrobial infections may play an important role in the development of SARS-CoV-2 infection in susceptible hosts. These coinfections may increase the risk of disease severity and pose challenges to the diagnosis, treatment, and prognosis of COVID-19. There have been limited SARS-CoV-2 coinfection studies. In this retrospective study, residual nucleic acid extracts from 796 laboratory-confirmed COVID-19-positive specimens, collected between March 2020 and February 2021, were analyzed using a Luminex NxTAG respiratory pathogen panel (RPP). Of these, 745 returned valid results and were used for analysis; 53 (7.1%) were positive for one or more additional pathogens. Six different respiratory viruses were detected among the 53 SARS-CoV-2-positive patient specimens, and 7 of those specimens tested positive for more than one additional respiratory virus. The most common pathogens include rhinovirus/enterovirus (RV/EV) ( n  = 22, 41.51%), human metapneumovirus (hMPV) ( n  = 18, 33.9%), and adenovirus ( n  = 12, 22.6%). Interestingly, there were no SARS-CoV-2 coinfections involving influenza A or influenza B in the study specimens. The median age of the SARS-CoV-2-positive patients with coinfections was 38 years; 53% identified as female, and 47% identified as male. Based on our retrospective analysis, respiratory coinfections associated with SARS-CoV-2-positive patients were more common in young children (≤9 years old), with white being the most common race. Our findings will likely prompt additional investigation of polymicrobial infection associated with SARS-CoV-2 during seasonal respiratory pathogen surveillance by public health laboratories. IMPORTANCE This examination of respiratory pathogen coinfections in SARS-CoV-2 patients will likely shed light on our understanding of polymicrobial infection associated with COVID-19. Our results should prompt public health authorities to improve seasonal respiratory pathogen surveillance practices and address the risk of disease severity.