As COVID-19 vaccinations continue to roll out, the question remains: Will additional booster shots be needed to maintain protection against the virus and its variants? Pfizer is already testing to see whether a third shot is necessary. Now, the company's CEO says that's probably the case.
"A likely scenario is that there will be likely a need for a third dose somewhere between six and 12 months, and then from there, there will be an annual revaccination -- but all of that needs to be confirmed," Pfizer CEO Albert Bourla said Friday while speaking on a CVS-hosted panel on the vaccination effort.
"There are vaccines like polio, that one dose is enough," Bourla explained, "and there are vaccines like flu that you need every year. The COVID virus looks more like the influenza virus than the polio virus."
The 30-minute discussion, moderated by CNBC correspondent Bertha Coombs and also featuring CVS Health President and CEO Karen S. Lynch, touched on the logistics of the ongoing vaccine rollout, as well as vaccination hesitancy.
More than 76 million people have been fully vaccinated in the US, according to Johns Hopkins University.
Bourla's remarks on the possibility of additional doses comes after Pfizer said in February that it was trialing a third COVID shot to be taken six to 12 months after the initial two-dose regimen, and examining whether such a shot would offer additional protection against any new strains of the virus that may yet emerge.
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On Friday, The Wall Street Journal reported that Johnson & Johnson -- whose vaccine rollout was paused this week over rare blood clot concerns -- privately reached out to rival vaccine makers Pfizer, Moderna and AstraZeneca to seek their help in studying clotting risks.
Pfizer and Moderna apparently declined, since their vaccines use different technology. AstraZeneca, whose vaccine has been subject to similar rare clotting concerns, agreed, the people said.