Researchers from Bar-Ilan University and Ziv Medical Center have presented preliminary evidence that people previously infected with coronavirus responded positively and strongly to a dose of the Pfizer vaccine, regardless of when they were infected and whether or not they had detectable antibodies before. to be inoculated. .
The study was conducted on a group of 514 staff members from the Ziv Medical Center in Safed, 17 of whom were infected with COVID-19 between one and 10 months before receiving the first dose of the vaccine.
The group’s antibody levels were measured before and after receiving the injection to determine the response to the vaccine.
The response among those previously infected was so effective that it opens the debate as to whether one dose of the vaccine may be sufficient in certain situations.
“This finding can help countries make informed decisions regarding vaccine policy, for example whether previously infected people should be vaccinated with priority and, if so, with how many doses,” says Professor Michael Edelstein of the Bar-Ilan University School of Medicine. who led the study.
“It also offers peace of mind that not having detectable antibodies after infection does not necessarily mean that post-infection protection is lost,” he says.
However, the researchers emphasized that their findings need to be confirmed in a larger cohort before reaching definitive conclusions.
Researchers continue to track healthcare workers after their second dose to better understand how long the COVID-19 vaccine will protect in different groups of people.
France recommended on Friday that people who have already recovered from Covid-19 receive a single dose of the vaccine, becoming the first country to issue such guidance.