The U.S. Centers for Disease Control and Prevention (CDC) is still investigating a potential stroke risk associated with Pfizer’s bivalent COVID-19 vaccine, after a recent study suggested a link between the shot and an increased risk of ischemic stroke.

The study, which was published in the New England Journal of Medicine, found that out of the more than 8 million people who received the vaccine, there were 43 cases of ischemic stroke reported in the first two weeks after vaccination, compared to the expected rate of 27 cases.

The CDC has said that while the study raised some concerns, it is still too early to draw any conclusions about a potential link between the vaccine and stroke risk.

The agency has also noted that the overall risk of stroke is still very low, and that the benefits of the vaccine far outweigh any potential risks.

The agency is continuing to investigate the matter and has urged healthcare providers to continue to report any cases of stroke that occur after vaccination.

The agency is also recommending that people who receive the vaccine continue to practice good health habits, such as eating a healthy diet, exercising regularly, and not smoking.