The current mRNA COVID-19 encodes for the spike protein. One needs to have an assay specifically designed to detect IgG directed against the spike protein to see a positive response to a vaccination.

Please review the enclosed CDC guidance.

https://www.cdc.gov/coronavirus/2019-ncov/lab/resources/antibody-tests-guidelines.html

Specifically the CDC states that “Antibody testing is not currently recommended to assess for immunity to COVID-19 following COVID-19 vaccination or to assess the need for vaccination in an unvaccinated person. Since vaccines induce antibodies to specific viral protein targets, post-vaccination serologic test results will be negative in persons without history of previous natural infection if the test used does not detect antibodies induced by the vaccine.”

I hope this information is helpful for you and your patients.

Eric Macy, MD, MS, FAAAAI