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S. African Variant Can ‘Break Through’ Pfizer Protection

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April 13, 2021 -- An Israeli study found that the South African coronavirus variant, B.1.351, can “break through” protection offered by the Pfizer/BioNTech vaccine, Reuters has reported.

"We found a disproportionately higher rate of the South African variant among people vaccinated with a second dose, compared to the unvaccinated group,” Tel Aviv University's Adi Stern said. “This means that the South African variant is able, to some extent, to break through the vaccine's protection.”

The study was conducted by Tel Aviv University and Clalit, Israel's largest healthcare provider. It compared 400 people who tested positive for COVID-19 two weeks or more after receiving one or two doses of the Pfizer vaccine against 400 unvaccinated patients of the same age and gender, Reuters said.

The South African variant was found in about 1% of all the COVID cases in both groups, Reuters said. Patients who got two doses had a higher prevalence rate than unvaccinated people -- 5.4% compared to 0.7% respectively, Reuters said.

The researchers cautioned that a small number of people were studied and that the South African variant is still very rare in Israel.

Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases, said Monday that breakthrough infections will always happen.

"We see this with all vaccines, in clinical trials and in the real world. No vaccine is 100% efficacious or effective, which means that we will always see breakthrough infections, regardlessof the efficacy of the vaccine," Fauci said during a virtual White House briefing on Monday, according to The Hill.

He said a vaccine has value because it will protect against serious disease, even if a virus breaks through the vaccine’s protection. He gave influenza as an example.

Speaking directly to the Israeli study, Fauci said it was misleading and makes it sound like people who get two doses of the Pfizer vaccine have a higher chance of COVID infection than unvaccinated people.

Fauci if an infection does break through the protection offered by a vaccine, it will likely be the "more difficult variant," but "that doesn't mean you have a greater chance of getting it," the Hill said.

WebMD Health News Brief


Reuters. “South African variant can 'break through' Pfizer vaccine, Israeli study says”

The Hill. “Fauci says some 'breakthrough' infections after vaccinations 'inevitable'”

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