Researchers from Bar-Ilan University and the Ziv Medical Center have presented preliminary evidence that people previously infected with coronavirus responded positively and strongly to one dose of the Pfizer vaccine, regardless of when they were infected and whether they had detectable antibodies. before they were vaccinated. .
The study was performed on a group of 514 staff members at the Ziv Medical Center in Safed, 17 of whom were infected with COVID-19 for between one and ten months before receiving the first dose of the vaccine.
2 View the gallery
A member of the medical staff receiving the coronavirus vaccine at Sheba Medical Center near Tel Aviv
(Photo: Yariv Katz)
Antibody surveys of the group were measured before and after receiving the shot to determine the response to the vaccine.
The response among those previously infected was so effective that it opened the debate as to whether one dose of the vaccine might be sufficient in certain situations.
“This finding could help countries make informed vaccine policy decisions – for example, whether those previously infected should be vaccinated, and if so, with how many doses,” says prof. Michael Edelstein of the Faculty of Medicine of Bar-Ilan University, who led the study.
“It also provides the assurance that detecting antibodies after infection does not necessarily mean that protection is lost after infection,” he says.
However, the researchers stressed that their findings need to be confirmed in a larger group before making definitive conclusions.
The researchers continue to track down health workers after their second dose to better understand how long the vaccine will protect against COVID-19 in different groups of people.
France on Friday recommended that people who have already recovered from Covid-19 should receive a single dose of vaccine, becoming the first country to provide such guidance.