Recipients of two doses of the Pfizer vaccine have strong protection against the delta variant that has been linked to rising coronavirus figures in the U.S., according to a study published this week.
The study, published this week in the New England Journal of Medicine, found the Pfizer product to be 88% effective against the delta variant and 93.7% effective against the alpha variant.
The study examined results from more than 38,000 sequenced tests.
"Overall, we found high levels of vaccine effectiveness against symptomatic disease with the delta variant after the receipt of two doses," the study’s authors wrote in their report.
Those receiving only one dose of the Pfizer vaccine had protection that was substantially lower: The vaccine was only 30.7% effective against delta for those who received just one shot, the report said.
The same study also examined the effectiveness of the AstraZeneca vaccine, which is used in Britain. That product was found to be 67% effective against the delta variant and 74.55% effective against the alpha variant, the report said.
The Pfizer findings matched those of an earlier study by Public Health England, which also showed two doses to provide 88% protection against delta. But Israel’s Health Ministry claimed earlier this month that Pfizer provided just 64% protection against delta, according to its observations.
But the Israel study confirmed that the Pfizer product was highly effective for preventing serious coronavirus symptoms and hospitalization, with both results at higher than 90%.
The delta variant is over 200% more transmissible than the original coronavirus, health officials have said.