The study did not consider the coronavirus vaccine made by Johnson & Johnson, but one of the researchers said he expected the immune response to be less durable than that produced by mRNA vaccines. File photograph: Saul Martinez/The New York Times

The vaccines made by Pfizer-BioNTech and Moderna set off a persistent immune reaction in the body that may protect against the coronavirus for years, (...)

Scientists worry that if vaccinated people are silent spreaders of the virus, they may keep it circulating in their communities, putting unvaccinated people at risk. Photograph:  Matthew Horwood/Getty

The new Covid-19 vaccines from Pfizer and Moderna seem to be remarkably good at preventing serious illness. But it’s unclear how well they will curb t(...)

Although researchers cannot forecast how long these immune responses will last, many experts consider the data an indication that the body’s most studious cells are doing their job. Photograph: iStock

To the immune system, not all germs are equally memorable. But our body’s cells seem to be seriously studying up on the coronavirus. Scientists who h(...)