Experts at Kyoto University have estimated the efficacy of the Pfizer vaccine at 85 percent to 96 percent, the Japanese TV channel NHK reported on Monday.
According to the news channel, a group of researchers from Kyoto University conducted a study last summer and analyzed the data of more than 10,000 local residents infected during this period.
The vast majority of those infected were unvaccinated, which allowed Japanese specialists to calculate the efficacy of the drug.
Among men aged 20 to 60 years, the efficacy of the Pfizer vaccine was 89.6 percent to 93.4 percent, among men over 60 at 94.7 percent to 96.9 percent.
Among women aged 20 to 60 years, the drug showed efficacy of 85.4 percent to 91.8 percent, and among women over 60 at 92.6 percent to 96.1 percent.
The Japanese experts said the study was carried out during the period of the powerful spread of the Delta strain in the country, and suggested that the vaccine is quite effective against this more infectious variant.
To date, at least 50 percent of Japanese people have been vaccinated with two doses of the coronavirus vaccine.
Japan uses the vaccines by the British-Swedish company AstraZeneca, the American-German consortium of companies Pfizer and BioNTech, as well as the American company Moderna.
Source: Philippines News Agency