Until recently, doctors didn’t think it made a difference which arm patients got their COVID-19 vaccine in. But a new study from Oregon Health & Science University shows that switching arms between doses could lead to as much as a fourfold increase in immune response. Though further studies are necessary, researchers suspect the improvement has to do with how the body learns to protect itself against viruses, meaning the results could be replicated in other multi-dose vaccine regimens. 

Marcel Curlin is an associate professor of medicine and the medical director for occupational health at OHSU. He joins us to talk about what these findings could mean for future vaccine protocols.