One of the most interesting and clarifying discussions I’ve read in recent weeks is Dr. Monica Gandhi’s discussion of the difference between ‘colonization’ and ‘infection’ in thinking about what counts as a case of COVID. It’s conceptually interesting but also highly relevant both for the choices we make balancing risk as individuals as well as how we approach the vaccine phase of the pandemic in policy terms.
As Gandhi tells it, in many cases a vaccinated individual will be exposed to COVID and have the pathogen briefly colonize their nasal passages. But vaccine-induced immunity will fight and defeat the virus there. Is that an infection or a case? If you take a PCR test, you’ll test positive. But Gandhi says we’re confusing things by treating it as one.
Gandhi is an infectious disease specialist and we spoke with her this morning in an Inside Briefing about this and related topics.
If you’re a TPM member you can watch our full interview after the jump.