Home » Do we need COVID-19 booster vaccines? ‘We don’t know,’ Fauci says

Do we need COVID-19 booster vaccines? ‘We don’t know,’ Fauci says

Dr. Anthony Fauci, the nation’s leading infectious disease expert, on Friday said it’s unclear whether coronavirus booster shots will be necessary, or when. However heads of major drug companies Pfizer and Moderna say the shots could be necessary by September.

Ongoing lab studies assessing durability of the immune response and breakthrough infections will help experts understand whether the shots are necessary, Fauci said. Pfizer and Moderna have been developing booster shots in a bid to protect against emerging variants, especially a concerning variant first detected in South Africa. While some viral strains have diminished vaccine efficacy, experts believe the existing vaccines remain effective.

“We are planning for the eventuality that we might need to boost people,” Fauci told CBS ‘This Morning’ co-hosts. “We don’t know whether we will have to do it and when we will have to do it. There’s estimates, ‘well it may be a year, it may be a little bit longer,’ the fact is we don’t know.”


“But it would really be foolish not to plan for the possibility that we might have to boost people,” he added.

Fauci attempted to unravel an assumption that booster vaccines could be necessary within six months, saying instead, this “is not the case at all.”

“We just keep following the durability of the response and if the time comes when we’ll need to boost people, we’ll at least have enough data because we’re doing the studies now to know what we expect to see when we do boost people.”

However, CEOs of Pfizer and Moderna reportedly told Axios that the first Americans who received COVID-19 vaccines could need a booster shot by September. Pfizer CEO Bourla said the company was “in the middle of the trials,” with data expected within two months. He said those who completed the two-dose regimen may need a booster within eight to 12 months following the second dose, but the company awaits data to confirm this.


Meanwhile, two of Moderna’s COVID-19 vaccine booster shots under study induced an immune response against SARS-CoV-2 and variants first identified in South Africa and Brazil, the company announced earlier this month. A variant-specific booster shot resulted in higher levels of neutralizing antibodies against the South African variant with fewer side effects than a third shot of the original vaccine.

“As we seek to defeat the ongoing pandemic, we remain committed to being proactive as the virus evolves. We are encouraged by these new data, which reinforce our confidence that our booster strategy should be protective against these newly detected variants,” Stéphane Bancel, CEO of Moderna, said in a previous statement.

Zaraki Kenpachi