01/16/2013 12:30 pm ET Updated Dec 06, 2017

Should I Get a Flu Shot Every Year?

This question originally appeared on Quora.
Answer by David Agus, M.D., Professor of Medicine and Engineering

I'm a big believer in flu vaccines. I think they should be mandatory for most people. If not to prevent the flu, then to at least prevent marked increases of inflammation that can come back to haunt us later in life when we grow ever more vulnerable to diseases rooted in unhealthy inflammation, a biological process that has been linked to some of our most troubling degenerative diseases today, including heart disease, Alzheimer's disease, cancer, autoimmune diseases, diabetes, and accelerated aging.

In 2006, the American Heart Association and the American College of Cardiology jointly recommended influenza immunization as part of comprehensive secondary prevention in persons with coronary and other atherosclerotic vascular disease. This was based on evidence from studies that indicated that annual vaccination against seasonal influenza in people with cardiovascular conditions prevents fatal heart attacks and strokes and even reduces the risk of death from any illness.

I firmly believe that it should also be part of primary prevention. If you choose not to get vaccinated every year (against all medical advice), then do what you can to avoid contact with others who are sick. Practice good hygiene and stay away from people with runny noses. I don't mean to sound pedantic or unimaginative, but this kind of advice is underestimated, yet vitally important. Seasonal influenza epidemics are a major public health concern, causing tens of millions of respiratory illnesses and 250,000 to 500,000 deaths worldwide each year.

In addition to seasonal influenza, a new strain of influenza virus against which no previous immunity exists and that is transmissible human-to-human could result in a pandemic with millions of fatalities. The swine flu scare that occurred in 2009 will someday be dwarfed by a real epidemic that will spread rapidly through virgin immune systems and kill millions in its path (as happened, for example, in the flu pandemic of 1918, when an estimated 50 to 100 million people died).

This answer is not a substitute for professional medical advice. This answer is for general informational purposes only and is not a substitute for professional medical advice. If you think you may have a medical emergency, call your doctor or (in the United States) 911 immediately. Always seek the advice of your doctor before starting or changing treatment. Quora users who provide responses to health-related questions are intended third party beneficiaries with certain rights under Quora's Terms of Service (

More questions on Influenza: