New data from a database of the Centers for Disease Control and Prevention (CDC, its sigal in English) of the USA. show a possible link to stroke risk for older adults who received an update to the Pfizer/BioNTech bivalent vaccine for Covid-19, despite the signal being weaker than the agency had reported in early January, health officials said Thursday.
The officials of the US Food and Drug Administration (FDA, its acronym in English) said they had not detected a link between injections and strokes in two other security monitoring databases.
The new data were presented at a meeting of outside experts who advise the FDA on vaccine policy.
Earlier this month, US health officials said they had detected the possible link with ischemic strokes in people older than 65 years who received the newest booster shots in your database Vaccine Safety Datalink (VSD). They said at the time that it was highly unlikely that it represented a real clinical risk.
Dr. Nicola Klein, from the healthcare company Kaiser Permanentewhich maintains VSD data for the CDC, said that the rate of strokes observed in the database had dropped in recent weeksbut that the signal was still statistically significantwhich means it’s probably not by chance.
Most confirmed cases they also received a flu shot at the same time, which could be a factor, he said.
FDA scientist Richard Forshee said that the agency plans to study whether there is an increased risk of stroke from receiving the two injections at the same time.
both agencies still recommend that older adults receive booster shots, now adapted to target the Omicron variants as well as the original coronavirus.
Dr. Walid Gellad, professor of medicine at the University of Pittsburgh, He said the topic requires further investigation.
“Sometimes the signals are not clear”, Gellad said in an email. “It makes sense to investigate further, and it doesn’t make sense to change practice given the known benefits (of receiving the booster) in this age group.”
Chile was the first country in Latin America to have the bivalent vaccine from the Pfizer-BioNTech laboratory. The first shipment of vaccines included 334,800 doses, which began to be applied first only for the population at risk.
It is a vaccine that combines the information of the RNA code of the original strain of Covid-19 and the RNA information of the Ómicron variant protein is added, which determines the bivalent term, because Two encodings are being used, that of the original virus and that of the Omicron variant, which has become the variant with the highest circulation in the world.
