Coinfection with SARS-CoV-2 and Influenza A Virus Increases Disease Severity and Impairs Neutralizing Antibody and CD4 <sup>+</sup> T Cell Responses
Eun-Ha Kim, Quyen Thi Nguyen, Mark Anthony B. Casel, Rare Rollon, Se‐Mi Kim, Young‐Il Kim, Kwang-Min Yu, Seung‐Gyu Jang, Jihyun Yang, Haryoung Poo, Jae U. Jung, Young Ki Choi
Abstract
The cocirculation of influenza virus merging with the COVID-19 pandemic raises a potentially severe threat to public health. Recently, increasing numbers of SARS-CoV-2 and influenza virus coinfection have been reported from many countries. It is a worrisome issue that SARS-CoV-2 coinfection with other pathogens may worsen the clinical outcome and severity of COVID-19 and increase fatality. Here, we evaluated SARS-CoV-2 and IAV coinfection using the K18-hACE2 mouse model. Coinfected mice exhibited increased mortality with prolonged IAV shedding. Furthermore, coinfected mice showed a higher level of cytokines and chemokines than a single infection condition. Interestingly, our data show that coinfected mice showed significantly fewer virus-specific and neutralizing antibodies than the mice with a single infection. Overall, this study suggests that coinfection aggravates viral pathology by impaired neutralizing antibody response.