have a question for Dr. Lam:

I assume that the antigen tests are developed using an antibody that binds to a specific epitope on the S-protein. We've seen multiple mutations in this protein, which in fact, correspond to the variants, both of concern and of less concern. Is there any systematic approach to evaluating historic or current tests against the variants? Are there tests that should be recalled?

Hi David, most rapid tests are actually detecting the presence of nucleocapsid proteins, not spike proteins, because exactly of your concern with the high prevalence of spike proteins. Interestingly, our own Center in Atlanta, is constantly re-testing the tests of the market whenever new variants of concern emerge. In addition, we're developing a more high tech, structural biology approach called epitope mapping to predict which tests are at risk for "missing" detection of new variants (even theoretical or hypothetical ones) - more to come on that!