Timeline and duration of vaccine efficacy still uncertain: Virus expert

Dan Barouch, Director of Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center says a vaccine could be available by early-2021, but only if everything goes perfectly during human trials. He also says the duration of immunity of a vaccine is still unknown, pointing out that antibodies in recovered patients declined quickly.
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Tue, Jul 21 20209:33 PM EDT