Receiving a vaccination in the late summer or fall could help reduce the risk of a first heart attack by an average of 19%, according to a new study.

British researchers examined 78,706 patients in England and Wales for their study. A total of 8,472 of them had received a flu vaccine and 16,012 had had a heart attack. Patients who had received a flu vaccine early in the season—sometime between September and mid-November—lowered their risk of heart attack by 21%. The benefit for late-season vaccine recipients was lower, with a roughly 12% reduced risk, according to the study.

Heart attacks typically increase during the winter. It has been suggested there may be a link between heart attack and respiratory infection, according to a press release from the Canadian Medical Association Journal, which published the study on Monday. Researchers say that further study into the link could lead to changes in recommended timing and targets for flu vaccine efforts.