WASHINGTON (NewsNation Now) — Dr. Anthony Fauci says vaccinated Americans would “not necessarily” need to get booster shots this fall for further protection from COVID-19.

Fauci, the nation’s leading infectious disease expert, told CBS “This Morning” on Friday that scientists would be tracking data on the virus and possible variants. He says it was still “possible” an additional shot would be needed later this year to ward off possible infection.