Prior aerosol infection with lineage A SARS-CoV-2 variant protects hamsters from disease, but not reinfection with B.1.351 SARS-CoV-2 variant

Yinda, K. C.; Port, J.; Bushmaker, T.; Fischer, R.; Schulz, J.; Holbrook, M.; Shaia, C.; de Wit, E.; van Doremalen, N.; Munster, V.

doi:10.1101/2021.05.05.442780

bioRxiv · 10.1101/2021.05.05.442780

Prior aerosol infection with lineage A SARS-CoV-2 variant protects hamsters from disease, but not reinfection with B.1.351 SARS-CoV-2 variant

Yinda, K. C.·Port, J.·Bushmaker, T.·Fischer, R.·Schulz, J.·Holbrook, M.·Shaia, C.·de Wit, E.·van Doremalen, N.·Munster, V.

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Abstract

The circulation of SARS-CoV-2 has resulted in the emergence of variants of concern (VOCs). It is currently unclear whether previous infection with SARS-CoV-2 provides protection against reinfection with VOCs. Here, we show that low dose aerosol exposure to hCoV-19/human/USA/WA-CDC-WA1/2020 (WA1, lineage A), resulted in a productive mild infection. In contrast, low dose of SARS-CoV-2 via fomites did not result in productive infection in the majority of exposed hamsters and these animals remained non-seroconverted. After recovery, hamsters were re-exposed to hCoV-19/South African/KRISP-K005325/2020 (VOC B.1.351) via an intranasal challenge. Seroconverted rechallenged animals did not lose weight and shed virus for 3 days. They had little infectious virus and no pathology in the lungs. In contrast, shedding, weight loss and extensive pulmonary pathology caused by B.1.351 replication was observed in the non-seroconverted animals. The rechallenged seroconverted animals did not transmit virus to naive sentinels via direct contact transmission, in contrast to the non-seroconverted animals. Reinfection with B.1.351 triggered an anamnestic response that boosted not only neutralizing titers against lineage A, but also titers against B.1.351. Our results confirm that aerosol exposure is a more efficient infection route than fomite exposure. Furthermore, initial infection with SARS-CoV-2 lineage A does not prevent heterologous reinfection with B.1.351 but prevents disease and onward transmission. These data suggest that previous SARS-CoV-2 exposure induces partial protective immunity. The reinfection generated a broadly neutralizing humoral response capable of effectively neutralizing B.1.351 while maintaining its ability to neutralize the virus to which the initial response was directed against.

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Yinda, K. C., Port, J., Bushmaker, T., Fischer, R., Schulz, J., Holbrook, M., Shaia, C., de Wit, E., van Doremalen, N., Munster, V.. 2021-05-05. Prior aerosol infection with lineage A SARS-CoV-2 variant protects hamsters from disease, but not reinfection with B.1.351 SARS-CoV-2 variant. https://doi.org/10.1101/2021.05.05.442780

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