Coronavirus antibodies may provide protection against reinfections even if they wane over time, according to experts, who say people shouldn't be alarmed by a pair of studies released this week that had seemingly contradictory results. Most experts agree that drops in antibody levels over time are expected, and that the declines reported are not altogether concerning.

"The question is: How much antibodies do you need to prevent reinfection?" one expert said. "It may be that you need very little."