How Long Will Vaccine Protection Last?

In this week's edition of the Covid Q&A, we look at immunity after vaccination. In hopes of making this very confusing time just a little less so, each week Bloomberg Prognosis is picking one question sent in by readers and putting it to an expert in the field. This week's question comes to us from John. He wonders whether it's safe to plan travel or other activities that would take place months after vaccination — would he still be immune to the virus?

How will one know how long a Covid vaccine is effective?

As more people get vaccinated, we're starting to imagine what life might look like when things go back to normal. Things like going to the movies or having a birthday party — even international travel — suddenly seem within reach again.

The U.S. Centers for Disease Control and Prevention advises that those who are fully vaccinated can hang out with each other indoors without social distancing. But it's still important to maintain precautions in public and around unvaccinated people for a few reasons. Though vaccines do seem to at least greatly reduce transmission, it's still unclear whether vaccinated people can still spread the virus.