Two doses of Pfizer shoot 88 percent effective in preventing the Delta variant while two doses of AstraZeneca are 67 percent effective.
Two doses of Pfizer or AstraZeneca COVID-19 vaccine are almost the same effective against the highly transmissible variant of Delta coronavirus since they are against the dominant Alpha variant before, according to a new study.
Research published in the New England Journal of Medicine on Wednesday showed that vaccines were very effective against the Delta variant, now the dominant strain in the world, as long as one person received two shots.
The study confirms the main findings from Public Health England (PHE) in May on the effectiveness of COVID-19 vaccines made by Pfizer-BioNTech and Oxford-AstraZeneca based on real-world data.
The study on Wednesday found that Pfizer was 88 percent effective in preventing symptomatic disease from the Delta variant with the two doses, compared with 93.7 percent against the Alpha variant, largely equal to previous data.
Two shots of AstraZeneca vaccine they were 67 percent effective against the Delta variant, in addition to the 60 percent reported initially, and 74.5 percent effective against the Alpha variant, compared with an original estimate of 66 percent efficacy.
“Only modest differences in vaccine efficacy were noted with the Delta variant compared with the Alpha variant after receiving two doses of vaccines,” the Public Health England researchers wrote.
Israel data have estimated that Pfizer’s stroke is less effective against symptomatic diseases, although protection against serious diseases remains high.
PHE had already stated that the first dose of the two vaccines was about 33 percent effective against symptomatic diseases from the Delta variant.
Other vaccines are also helpful
The full study published Wednesday found that one dose of Pfizer vaccine was 36 percent effective and one dose of the AstraZeneca vaccine was about 30 percent effective.
“Our finding of reduced efficacy after the first dose would support efforts to maximize vaccine intake with two doses between vulnerable groups in the context of circulating the Delta variant,” say the study authors.
Recently, researchers at Beth Israel Deaconess Medical Center in the American city of Boston also said that in a laboratory environment, the antibody response from the Johnson & Johnson vaccine to a dose worked well against Delta and that the immune response lasted about eight months.
In June, creators of Sputnik vaccine from Russia he also said it was about 90 percent effective against the highly contagious Delta variant.
The strain, which Russia has actively traded abroad, had previously been found by researchers to be nearly 92 percent effective against the original strain of coronavirus.
Denis Logunov, deputy director of the Moscow Gamaleya Institute that developed Sputnik, said that the figure of the effectiveness of the Delta variant was calculated on digital medical and vaccine records, said the Russian news agency RIA.
The Sputnik vaccine, however, has caused some controversy since it was introduced to the public even before a full trial was completed. It is still waiting for approval from the World Health Organization.