SARS-CoV-2 variants lacking a functional ORF8 may reduce accuracy of serological testing

Serological testing can be used for diagnosis, retrospective assessment of the efficacy of control measures and testing the response to a future vaccine (Weissleder et al., 2020). Most antibody detection assays to estimate SARS-CoV-2 prevalence and incidence probe for the nucleocapsid (N) or spike (S) proteins (Weissleder et al., 2020). A recent study proposed the use of ORF8 and ORF3b antibodies as serological markers of early and late SARS-CoV-2 infection (Hachim et al., 2020). The study is an important step towards standardization of serological assays for COVID-19 and a better understanding of SARS-CoV-2 pathogenicity. ORF8 antibodies were identified as a major marker of acute, convalescent and long-term antibody response to SARS-CoV-2. However, several lineages without a functional ORF8 exist that may affect the accuracy of serological testing (Gong et al., 2020; Pereira, 2020; Su et al., 2020; To et al., 2020). It is important to be aware of this limitation when testing for COVID-19.