Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently a serious public health concern worldwide. Notably, co-infection with other pathogens may worsen the severity of COVID-19 symptoms and increase fatality. Here, we show that co-infection with influenza A virus (IAV) causes more severe body weight loss and more severe and prolonged pneumonia in SARS-CoV-2-infected hamsters. Each virus can efficiently spread in the lungs without interference by the other. However, in immunohistochemical analyses, SARS-CoV-2 and IAV were not detected at the same sites in the respiratory organs of co-infected hamsters, suggesting that either the two viruses may have different cell tropisms in vivo or each virus may inhibit the infection and/or growth of the other within a cell or adjacent areas in the organs. Furthermore, a significant increase in IL-6 was detected in the sera of hamsters co-infected with SARS-CoV-2 and IAV at 7 and 10 days post-infection, suggesting that IL-6 may be involved in the increased severity of pneumonia. Our results strongly suggest that IAV co-infection with SARS-CoV-2 can have serious health risks and increased caution should be applied in such cases.
【저자키워드】 Infectious diseases, Virology, 【초록키워드】 COVID-19, coronavirus disease, severe acute respiratory syndrome coronavirus 2, viruses, public health, SARS-CoV-2, Coronavirus disease 2019, coronavirus, Pneumonia, hamsters, IL-6, Influenza, body weight, severity, Infection, influenza A virus, lung, risk, Symptom, severe acute respiratory syndrome Coronavirus, virus, influenza A, Spread, Health, pathogen, severity of COVID-19, sera, Lungs, Co-infection, Pathogens, cell tropism, hamster, respiratory, in vivo, COVID-19 symptoms, fatality, Interference, weight loss, Post-infection, acute respiratory syndrome, acute respiratory syndrome coronavirus, significant increase, growth, SARS-CoV-2-infected hamsters, organs, organ, Body weight loss, immunohistochemical analyses, IAV, Cell, caused, virus, involved, inhibit, cause, adjacent area, 【제목키워드】 SARS-CoV-2, Influenza virus, hamster, cause,