“Unfortunately, as [the virus] spreads it can also mutate,” he told CNBC’s Meg Tirrell during a Healthy Returns Spotlight event. “Every time it mutates, it’s almost like another click of the dial so to speak where we can see another variant, another mutation that can have an impact on its ability to fend off antibodies or to have a different kind of response not only to a therapeutic but also to a vaccine.”

Public health officials and infectious disease experts have said there is a high likelihood that Covid-19 will become an endemic disease, meaning it will become present in communities at all times, though likely at lower levels than it is now. Health officials will have to continuously watch for new variants of the virus, so scientists can produce vaccines to fight them, medical experts say.