Two doses of Pfizer and AstraZeneca protect Delta strain – Época Negócios

Two doses of the Covid vaccine from Pfizer/BioNTech or Oxford/AstraZeneca are effective against the delta variant of the Sars-CoV-2 coronavirus, which is more transmissible than the others, says a study published Wednesday (21) by the “New England Journal of Medicine”. Medicine”.

The analysis was based on data collected by the UK Institute of Health in the real world, which included 20,000 cases of the delta variant.

In the case of Cominarty, from Pfizer, the two doses were able to prevent symptoms of Covid-19 in 88% of cases, just below the result against the first strain, Alpha, which was 93.7%. Vaxzevria, from AZ, was 67% effective versus 74.5% effective against Alfa.

However, in both cases, the efficacy regressed after only the first dose and amounted to about 30%.

“Some modest differences in the efficacy of delta versus alpha-variable vaccines were observed after the two doses. The differences are most noticeable after only the first dose was received. These data support efforts to maximize full vaccination prevalence among at-risk populations,” the study authors say.

A recent study in Israel, which also has a population with advanced immunization, indicated a 30% reduction in the efficacy of Cominarty against the delta variant. But the data has not been revised.

However, both vaccines were created to prevent serious cases and deaths due to Covid-19, and so far, the efficacy in these cases is still very high. The delta variant has spread widely across the UK, becoming prevalent and triggering a strong wave of new cases.

Even with 88% of the population getting one of the available doses and 69.1% with a full vaccination course, the severe loosening of health rules and a delta boom mean Britons have an average of 47,600 cases per day – a level similar to the start of the year.