Detection of persistent SARS-CoV-2 IgG antibodies in oral mucosal fluid and upper respiratory tract specimens following COVID-19 mRNA vaccination (preprint)

Previous studies have shown that mRNA COVID-19 vaccines are highly effective at preventing SAR-CoV-2 infection by generating an immune response, which in part produces SARS-CoV-2 IgG antibodies in serum. In this study, we hypothesized that COVID-19 vaccines may elicit production of SARS-CoV-2 IgG antibodies in the upper respiratory tract, such as in oral and nasal mucosal fluid. To test that hypothesis, we enrolled 114 participants within 3-7 days of receiving the first dose of the Moderna mRNA COVID-19 vaccine and collected oral mucosal fluid samples on days 5, 10, 15, and 20 after each vaccine dose. Of participants naive to SARS-CoV-2 (n = 89), 79 (85.4%) tested positive for SARS-CoV-2 IgG antibodies by time point 2 (10 days +/-2 days after first vaccine dose), and 100% tested positive for SARS-CoV-2 IgG by time point 3 (15 days +/-2 days after first vaccine dose). Additionally, we collected paired oral mucosal fluid and anterior nares samples from 10 participants who had received both vaccine doses. We found that participants had an average SARS-CoV-2 IgG antibody concentration of 2496.0 +/-2698.0ng/mL in nasal mucosal fluid versus 153.4 +/-141.0ng/mL in oral mucosal fluid. Here, we demonstrate detection and longitudinal persistence of SARS-CoV-2 IgG antibodies in upper respiratory tract specimens following COVID-19 mRNA vaccination.

Rapid detection of SARS-CoV-2 antibodies in oral fluids (preprint)

Current commercially available methods for reliably detecting antibodies against SARS-CoV-2 remain expensive and inaccessible due to the need for whole blood collection by highly trained phlebotomists using personal protective equipment (PPE). We evaluated an antibody detection approach utilizing the OraSure Technologies' Oral Antibody Collection Device (OACD) and their proprietary SARS-CoV-2 total antibody detection enzyme-linked immunosorbent assay (ELISA). We found that the OraSure test for total antibody detection in oral fluid had comparable sensitivity and specificity to serum-based ELISAs while presenting a more affordable and accessible system with the potential for self-collection.

ELISA detection of SARS-CoV-2 antibodies in saliva (preprint)

To facilitate containment of the COVID-19 pandemic currently active in the United States and across the world, options for easy, non-invasive antibody testing are required. Here we have adapted a commercially available, serum-based ELISA for use with saliva samples, which will enable widespread, affordable testing for patients who experienced this disease.