Researchers at 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 became infected and whether or not they had antibodies. detectable before being inoculated. .
The study was conducted on a group of 514 staff members at Safed Ziv Medical Center, 17 of whom were infected with COVID-19 between one and ten months before receiving the first dose of the vaccine.
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A medical staff member who received the coronavirus vaccine at Sheba Medical Center near Tel Aviv
(Photo: Yariv Katz)
Antibody levels in the group were measured before and after receiving the vaccine in order to determine the response to the vaccine.
The response among those previously infected was so effective that it opens the debate on whether a dose of the vaccine may be sufficient in certain situations.
“This finding can help countries make informed decisions about 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 the security that not having detectable antibodies after getting infected doesn’t necessarily mean losing post-infection protection,” he says.
However, the researchers emphasized that their findings should be confirmed in a larger cohort before reaching definitive conclusions.
Researchers continue to monitor health care workers after their second dose to better understand how long the COVID-19 vaccine will protect in different groups of people.
On Friday, France recommended that people who have already recovered from Covid-19 receive a single dose of vaccine, becoming the first country to issue such guidelines.