Two new studies have found that the protection against COVID infection provided by the Pfizer vaccine falters within months of receiving a second dose, but the protection against serious illness, hospitalization and death is still strong.
These findings emerge from two studies that were conducted among highly vaccinated populations in Israel and Qatar and were published by The New England Journal of Medicine on Wednesday.
Studies bolster the argument that people who have been fully vaccinated should still make sure they take adequate protection against COVID-19 and that people get booster shots six months after getting their first two jabs. Point out the growing role of
One study conducted among 4,868 healthcare workers in Israel showed that the effectiveness of the vaccine among men who are 65 years of age or older and who are immunosuppressed — those with weakened immune systems — decreased six months after the second dose. go.
CNN cited the study as saying it showed that levels of neutralizing antibodies, which are the human immune system’s first line of defense against infection, correlated with protection against infection.
The Israel study pointed to other published research and said that the reduction in immunity delivered by the vaccine was not a feature of COVID vaccines, but was also found in vaccines against other diseases.
“Published work regarding several vaccines, such as those against measles, mumps and rubella, has shown a small reduction of 5 to 10 percent each year in neutralizing antibody levels,” it said.
“We found a significant and rapid reduction in the humoral response to the BNT162b2 vaccine [the Pfizer and BioNTech SE vaccine] was observed within months after vaccination,” it added.
Researchers conducting other studies in Qatar found that Pfizer’s vaccine protection against infection peaked in the first month after the second dose and then “month by month, before reaching low levels five to seven months after the second dose”. fell.
This meant that “a substantial portion of the vaccinated population” could lose protection against infection in the coming months, perhaps increasing the likelihood of new pandemic waves.
The study, however, also noted that the implications of the infection “remain to be clarified” in those vaccinated, even as the risk against hospitalization and death was 90 percent by six months after the second dose. remained strong at or more than that.
“BNT162B2-induced protection against hospitalization and death continued to decrease with barely six months after the second dose,” the study said.
“The implications of these findings on infection transmission remain to be clarified, but recent vaccine breakthrough infections in this same population were found to be less infectious than primary infections in non-vaccinated individuals,” it added.
The study warns that Qatar and other countries that have vaccinated it in large numbers may let citizens drop their guard after being vaccinated.
It said, “Vaccinated individuals have higher rates of social interaction than non-vaccinated individuals and may also have reduced adherence to safety measures.”
“This behavior may underestimate the vaccine’s real-world effectiveness compared to its biological effectiveness, possibly explaining the lack of safety,” it added.
Meanwhile, another study published in the Lancet The Journal reported some similar findings on Monday on the effectiveness of the Pfizer vaccine.
It said the immunity given by the vaccines declined from 88 percent to 47 percent six months after the second dose.
The study said the decline in effectiveness was not due to newly emerging coronavirus variants, but rather a consequence of its efficacy, Reuters reported.
The research, however, matches the findings of a Qatar study on the effectiveness of the Pfizer vaccine in preventing hospitalizations, saying that protection remains at 90 percent.
Credit: www.independent.co.uk /