Researchers at Tel Aviv University and Clalit discovered the prevalence of the South African variant among patients who received two doses of the Pfizer vaccine.

The Israeli study found that the South African variant has managed to break through the protection offered by two doses of the Pfizer vaccine to some extent. However, it is still unclear how much efficacy is lost.

The study compared about 400 people who tested positive for COVID-19 two weeks or more after receiving doses of Pfizer, against the same number of unvaccinated patients, according to an Aljazeera report.

The South African variant's prevalence was eight times higher than those unvaccinated.

The researchers suggested that the vaccine is less effective against the South African variant as compared to the original strain and the British variant.

Tel Aviv University's Adi Stern said that the variant can evade the vaccine's protection to some extent.

"Based on patterns in the general population, we would have expected just one case of the South African variant, but we saw eight," Stern was quoted in a CNBC report.

He added that more research is needed to conclude how much efficacy has been lost.

Pfizer has declined to comment on the suggested results of the Israeli study.

Meanwhile, Pfizer said they were doing some lab work to identify whether the vaccine can offer protection against another variant first discovered in Brazil.

Moderna earlier disclosed that there was a drop in antibody levels against the South African variant, according to The Guardian report.

Moderna added that the efficacy of its vaccine against the South African variant is yet to be known.

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COVID Variants

The Centers for Disease Control and Prevention director Dr. Rochelle Walensky cautioned the public, saying that she is worried the United States is facing "impending doom" with variants rampant as COVID cases are increase daily.

"We have so much to look forward to, so much promise and potential of where we are and so much reason for hope, but right now I'm scared," Walensky was quoted in a report.

Walensky added that the British variant, also known as B.1.1.7, is the most common variant spreading in the United States.

The B.1.1.7 is the most contagious COVID variant spreading in the country based on what the scientists found, according to an NBC News report.

Walensky added that most cases had been linked to daycare centers and youth sports. She noted that the rise in the COVID cases appeared to be from younger age groups.

The CDC predicted in January that the British variant could be the most dominant virus strain in the country by March.

The White House said that 108 million people in the U.S. have already received at least one shot, while vaccine eligibility has been moved up to all adult Americans by Apr. 19.

White House COVID-19 adviser Andy Slavitt called on the public to get the vaccine and practice certain measures, such as social distancing, frequent handwashing, and wearing a mask.

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