(AP) — Even people who have recovered from COVID-19 are urged to get vaccinated, and a new study shows survivors who ignored that advice had twice the risk of getting reinfected.

Friday's report from the Centers for Disease Control and Prevention comes as scientists urge everyone to get vaccinated as the extra-contagious delta variant spreads. That includes people who had a prior infection.

The report out of Kentucky adds to growing laboratory evidence that vaccines offer an important boost to natural immunity — including broader protection against new mutants.