Co-infection of influenza A virus enhances SARS-CoV-2 infectivity

Bai, L.; Zhao, Y.; Dong, J.; Liang, S.; Guo, M.; Liu, X.; Wang, X.; Huang, Z.; Sun, X.; Zhang, Z.; Dong, L.; Liu, Q.; Zheng, Y.; Niu, D.; Xiang, M.; Song, K.; Ye, J.; Zheng, W.; Tang, Z.; Tang, M.; Zhou, Y.; Shen, C.; Dai, M.; Zhou, L.; Chen, Y.; Yan, H.; Lan, K.; Xu, K.

doi:10.1101/2020.10.14.335893

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bioRxiv · 10.1101/2020.10.14.335893

Co-infection of influenza A virus enhances SARS-CoV-2 infectivity

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Abstract

The upcoming flu season in the northern hemisphere merging with the current COVID-19 pandemic raises a potentially severe threat to public health. Through experimental co-infection of IAV with either pseudotyped or SARS-CoV-2 live virus, we found that IAV pre-infection significantly promoted the infectivity of SARS-CoV-2 in a broad range of cell types. Remarkably, increased SARS-CoV-2 viral load and more severe lung damage were observed in mice co-infected with IAV in vivo. Moreover, such enhancement of SARS-CoV-2 infectivity was not seen with several other viruses probably due to a unique IAV segment as an inducer to elevate ACE2 expression. This study illustrates that IAV has a special nature to aggravate SARS-CoV-2 infection, and prevention of IAV is of great significance during the COVID-19 pandemic.

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Bai, L., Zhao, Y., Dong, J., Liang, S., Guo, M., Liu, X., Wang, X., Huang, Z., Sun, X., Zhang, Z., Dong, L., Liu, Q., Zheng, Y., Niu, D., Xiang, M., Song, K., Ye, J., Zheng, W., Tang, Z., Tang, M., Zhou, Y., Shen, C., Dai, M., Zhou, L., Chen, Y., Yan, H., Lan, K., Xu, K.. 2020-10-14. Co-infection of influenza A virus enhances SARS-CoV-2 infectivity. https://doi.org/10.1101/2020.10.14.335893

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