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bioRxiv · 10.1101/2024.04.03.587933

Comparative analysis of serological assays and sero-surveillance for SARS-CoV-2 exposure in US cattle

Abstract

Coronavirus disease-2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to pose a significant threat to public health globally. Notably, SARS-CoV-2 demonstrates a unique capacity to infect various non-human animal species, documented in captive and free-living animals. However, experimental studies revealed low susceptibility of domestic cattle (Bos taurus) to ancestral B.1 lineage SARS-CoV-2 infection, with limited viral replication and seroconversion. Despite the emergence of viral variants with potentially altered host tropism, recent experimental findings indicate greater permissiveness of cattle to SARS-CoV-2 Delta variant infection compared to other variants, though with limited seroconversion and no clear evidence of transmission. While some studies detected SARS-CoV-2 antibodies in cattle in Italy and Germany, there is no evidence of natural SARS-CoV-2 infection in cattle from the United States or elsewhere. Since serological tests have inherent problems of false positives and negatives, we conducted a comprehensive assessment of multiple serological assays on over 600 cattle serum samples, including pre-pandemic and pandemic cattle sera. We found that SARS-CoV-2 pseudovirus neutralization assays with a luciferase reporter system can produce false positive results, and care must be taken to interpret serological diagnosis using these assays. We found no serological evidence of natural SARS-CoV-2 infection or transmission among cattle in the USA. Hence, it is critical to develop more reliable serological assays tailored to accurately detect SARS-CoV-2 antibodies in cattle populations and rigorously evaluate diagnostic tools. This study underscores the importance of robust evaluation when employing serological assays for SARS-CoV-2 detection in cattle populations.

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BibTeXRIS

Ramasamy, S., Qureshi, M., Mukherjee, S., Mahajan, S., LaBella, L. C., Chothe, S. K., Jakka, P., Gontu, A., Misra, S., Surendiran-Nair, M., Nissly, R. H., Kuchipudi, S. V.. 2024-04-04. Comparative analysis of serological assays and sero-surveillance for SARS-CoV-2 exposure in US cattle. https://doi.org/10.1101/2024.04.03.587933

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