TORONTO — Going to your doctor for a flu shot may protect you from more than just a fever and the sniffles. A new study reveals a link between the virus and an increased risk of suffering a heart attack.

Researchers from the Institute for Clinical Evaluative Sciences  and Public Health Ontario say that a person diagnosed with the flu is six-times more likely to have a heart attack within the first week of symptoms.

Using data from about 20,000 local adults with confirmed cases of influenza from 2009 to 2014, the authors found 332 of those patients had suffered a heart attack within a year of the diagnosis.

Older adults, people who have never had a heart attack, and patients infected with the influenza B virus are especially at risk, the researchers found.

“Our findings are important because an association between influenza and acute myocardial infarction reinforces the importance of vaccination,” says Dr. Jeff Kwong, the study’s lead author, in a news release.

The study also showed that having other upper respiratory infections or related viruses raised the risk of an attack.

“People at risk of heart disease should take precautions to prevent respiratory infections, and especially influenza, through measures including vaccinations and handwashing,” says Kwong, who notes that previous research had shown the vaccine lowered the risk of other heart-related ailments.

The authors say that anyone diagnosed with the flu should be aware of symptoms related to heart attacks and shouldn’t hesitate to see a doctor if any are detected.

The full study was published Jan. 25 in the New England Journal of Medicine.