A coronavirus vaccine, when it arrives, probably won’t mean the virus is gone for good:

COVID-19 is so new that scientists aren’t sure whether you’re permanently immune once you’ve recovered, or if your antibodies fade after a few months. The same is true of an eventual vaccine. I-U Health infectious disease specialist Mary Kay Foster says realistically, the best hope is probably something like the flu, where you have to get re-vaccinated once a year.

Foster notes viruses mutate frequently, and a vaccine could become outdated. But she says today’s vaccines are focused on the virus’s genetic structure, and once a vaccine exists, it can be easily tweaked to accommodate those mutations, just as the annual flu vaccine is adjusted for the most prevalent strains that year.

Two vaccine trials have reported early success in the last month and are advancing to larger trials. If drug companies meet their goal of getting a vaccine approved by early next year, it’d be one of the fastest vaccine efforts in history. Foster says that doesn’t mean they’re skipping steps. She says the speed of the research reflects a global focus on creating a vaccine.