Harvard Health

The two V s vaccine and vigilance are your best tools for avoiding the flu

If you haven't gotten your flu shot yet, what are you waiting for? The hour or so it would take is nothing compared with the time you might spend fighting the flu or something worse -- like recovering from the heart attack it could trigger.

As of early October 2009, much of the focus has been on swine flu (more formally called H1N1 flu). That's understandable. H1N1 is new, and no one knows how much damage it will cause. But the "regular" flu isn't something to sneeze at. Seasonal flu kills about 36,000 people each year in the United States, hospitalizes more than 200,000, and costs us more than $10 billion in direct medical expenses and lost productivity.

Seasonal flu and H1N1 flu are different in some ways and similar in others. One of the similarities is that both may be hard on the heart. Getting vaccinated against seasonal flu and swine flu is good insurance for your health and heart.


Infections of any kind can affect the heart and circulatory system. Influenza (the flu) is no different. It can make breathing difficult, boost blood pressure, make the heart beat faster, and rev up inflammation. All of these force the heart to work harder. A healthy heart usually weathers these changes without a problem; a damaged or weakened heart may not. Infection can also cause a vulnerable, cholesterol-filled plaque inside a coronary artery to break apart. The blood clot that forms to seal the break can block the artery, causing a heart attack or sudden death.

Over the years, a number of studies have linked flu with cardiovascular problems. An analysis of 39 studies showed consistent connections between influenza and heart attack or cardiovascular-related death (Lancet Infectious Diseases, October 2009).

There's no reason to believe that the H1N1 flu will be any less hazardous to the heart, and some experts worry it could be even more devastating. At the 2009 European Society of Cardiology meeting in Barcelona, top cardiologists warned that swine flu and heart disease could be a deadly mix. Although most people with heart disease are over age 60 -- a group that seems to be less susceptible to the H1N1 virus -- there could be major complications for those who do catch it.

One reason is that H1N1 flu tends to infect the lungs rather than the upper airway, as is more common with seasonal flu. The accumulation of fluid coupled with flu-related breathing problems could severely stress individuals with heart failure, many of whom already have fluid buildup in the lungs.


If you come down with flulike symptoms -- a sore throat, fever or chills, headache or muscle aches, extreme tiredness, nausea, vomiting, or diarrhea -- there's no simple way to tell if you have seasonal flu or swine (H1N1) flu. A laboratory test for the H1N1 virus is the only sure way to tell the difference.

Most otherwise healthy folks recover fully from seasonal flu or H1N1 with rest, staying hydrated, and some ibuprofen or acetaminophen to help with pain or fever. Some people, though, will need antiviral medications or hospitalization. Seek medical care if you or the person you are caring for:

--has chest pain or difficulty breathing

--has purple or blue discoloration of the lips

--suddenly becomes dizzy

--has severe or persistent diarrhea or vomiting and is unable to keep liquids down

--is confused or isn't responsive.

If you are concerned about your illness, call your health care provider for advice. Use the emergency room as a last resort; if you go there and don't have the flu, it's a great place to catch it from those who do.


The two V's -- vaccine and vigilance -- are your best tools for avoiding the flu. Because seasonal flu contains a different mix of viruses each year, you need to get vaccinated every year. But this vaccine doesn't include anything to fight H1N1, which is why the U.S. Centers for Disease Control and Prevention worked feverishly to create a new vaccine for it.

For seasonal flu, older people and those with heart disease, lung disease, diabetes, or other chronic conditions are at the top of the list for getting the vaccine. That's not the case for H1N1. People born before 1957 are less likely to be stricken with the virus than younger people. That doesn't mean you shouldn't get the swine flu shot if you're older than that -- you should -- just that you won't be first in line.

Vigilance is even more important. You don't need to hibernate at home until summer. Following these tips can help keep you flu-free:

--Wash your hands often with soap and water. If soap and water aren't available, use an alcohol-based hand rub.

--Avoid touching your eyes, nose, and mouth. Germs spread this way.

--Cover your nose and mouth with a tissue when you cough or sneeze, then throw the tissuet in the trash. If you don't have a tissue or handkerchief, cough or sneeze into the crook of your arm, not into your hands.

--Try to avoid close contact with people who are sick. Young children can be vectors. Handle with care.

--If you feel like you have the flu, let your doctor know right away, especially if you have heart disease. You may benefit from Tamiflu or another antiviral drug, which can reduce the severity of the illness. Don't stop taking your regular medications without first consulting your health care provider. Let your doctor know about any difficulty breathing, if you suddenly get worse, or if you aren't getting better after three or four days.

Stay home for at least 24 hours after your fever is gone except for getting medical care or other necessities. While you're sick, limit contact with others as much as possible to keep from infecting them.



Seasonal: Occurs every year during the winter months

H1N1 or other pandemic flu: Occurs sporadically; can take place in any season

Seasonal: Affects 5 percent to 20 percent of the U.S. population

H1N1 or other pandemic flu: May affect up to one-third of the population

Seasonal: Kills 500,000 to 1 million people each year, including 36,000 to 40,000 in the United States.

H1N1 or other pandemic flu: The Spanish Flu of 1918 killed 50 million people worldwide and 500,000 in the United States; the course of H1N1 is unknown

Seasonal: Most people recover within a week or two.

H1N1 or other pandemic flu: In the early fall of 2009, H1N1 infections were relatively mild; this can change quickly if the virus mutates into a more severe strain.

Seasonal: All ages are susceptible; deaths are generally confined to the elderly, the very young, and those with heart disease, lung disease, or other chronic health conditions.

H1N1 or other pandemic flu: Younger people appear to be more susceptible to the virus than older people.

Seasonal: Vaccination is generally effective

H1N1 or other pandemic flu: The new H1N1 vaccine was effective in tests; how it will fare in the real world remains to be seen.

© Harvard Health Watch






Another Reason to Get a Flu Shot: To Protect Your Heart