Patients with heart failure are especially vulnerable to getting the flu. But a new study at the University of Wisconsin suggests those patients who get flu shots may not be getting full protection.
Researchers believe the condition of heart failure leads to impaired immune function. That makes these patients less able to respond to the flu vaccine, leaving them vulnerable to infection.
More than 5 million Americans have heart failure.
The study was presented at the American College of Cardiology meeting in Chicago.