British scientists have found that increasing the interval between two doses of Pfizer-BioNTech vaccine produces more antibodies. According to the BBC, an eight-week break is considered an ideal break.
The researchers say that increasing the interval seems to solve the problem of protection against the Delta variant. Initially, the decision to increase the interval between the two vaccines was made by the UK, at the end of last year, it was then 12 weeks. Then, as the vaccination campaign evolved, it was reduced to 8 weeks for all age groups over 18.
The work of British researchers is being prepared for publication and has not yet received a full peer review. In the course of scientific research, which was funded by the state, scientists studied the body’s immune response to two vaccinations, given at different intervals, in 503 NHS employees. The experiment was carried out at the end of last year and beginning of this year, at the height of the rapid spread of the Alpha Covid variant. When measuring the level of antibodies, the following results were obtained:
at any interval between two doses of Pfizer, the body as a whole produced a strong immune response; The 3-week schedule generated fewer antibodies than the 10-week schedule; after the first vaccination, antibody levels fell, but levels of another type of immune cell, T cells, remained high; a longer interval between doses resulted in fewer T cells overall, but more of a specific type or subset of helper T cells. They, scientists believe, support immune memory.
Professor Suzanne Duanci, principal investigator of the work at Oxford University, notes that two doses are better than one, but the timing of the second vaccination was flexible, depending on the circumstances. Regarding the current situation, the professor says:
“Eight weeks is a sweet spot for me because people really want two vaccines. [дозы]and now there are many Delta. Unfortunately, I don’t see this virus going away, so you want to balance that with getting the best protection you can. “
One of the study’s authors from the University of Newcastle, Dr. Rebecca Payne, said:
“Our study provides encouraging evidence that both dosing regimens elicit a sustained immune response against Sars-CoV-2 after two doses. We now need to do more research to understand the full clinical relevance of our findings. ”
Health England data confirms that even a single dose of Pfizer is effective in significantly reducing severe illness, hospital admissions and mortality. Nadhim Zahavi, Minister of Vaccines, says:
“The findings from this latest Pitch study are extremely important not only for the UK but for the world in helping to better understand the mechanism of our immune response to Covid-19 and the importance of receiving both doses of the drug. When we were in a rush to offer the vaccine to all adults, we followed JCVI’s advice [Объединенного комитета по вакцинации и иммунизации] shorten the interval between doses from 12 to eight weeks to help protect more people from Delta. This latest study provides additional evidence that this interval leads to a strong immune response and supports our decision. I urge every adult to get both doses of the vaccine, to protect themselves and those around them, and we want to offer revaccinations to millions of the most vulnerable people from September to ensure that protection remains. ”