Although situation could change with new data, the US health regulators FDA and CDC have said that at this time, people who are fully vaccinated against the coronavirus do not need a third dose, Axios reports.
They added that they’re engaged in a science-based, rigorous process to consider whether or when a booster might be necessary, continuing to review any new data as it becomes available.
At the same time, Pfizer Inc’s chief scientific officer, Mikael Dolsten, said on Thursday that the company will apply for US authorization for a third dose of its Covid-19 jab within the next month faced with more contagious Delta strain of the virus and the fact that antibodies, as predicted, wane over time.
Early data from the company’s booster study suggested that people’s antibody levels jump five to 10-fold after a third dose, compared to their second dose months earlier. Although clinical trials last year showed Pfizer vaccine, developed jointly with German firm BioNTech, is 95% effective against severe disease, Dolsten said the company’s data shows it had slipped to the 80% range after six months.
Dolsten claimed data from Britain and Israel showing the Pfizer vaccine “neutralizes the delta variant very well,” but according to data from Israel’s health ministry, quoted by Bloomberg, Pfizer’s vaccine is significantly less effective at preventing infection with the Delta variant than previous strains of Covid-19.
Israel’s health ministry reported Monday, quoting the results of its early study, that a full course of the Pfizer-BioNTech vaccine is 64% effective at preventing symptomatic Covid-19, much lower than previous estimates of nearly 90%.
The company said on Twitter that it would also prepare an “updated version” of the jab to improve effectiveness against the Delta variant with clinical studies planned to begin by August.
CDC and health experts believe the Delta variant will become the dominant strain in the US and point it already accounts for around one in four cases of Covid-19 and is dominant form of the virus in two regions the agency measures (making up around 50-60% of cases in an area covering Iowa, Kansas, Missouri, Nebraska, Colorado, Montana, North Dakota, South Dakota, Utah and Wyoming).