In this country, in an average year, 36,000 people die from influenza and its complications (particularly pneumonia), and most of those victims are over the age of 65. Influenza causes over 200,000 hospitalizations in the US each year. (These statistics are from the Centers for Disease Control).

When I was practicing medicine, our hospital prepared for the “flu season” by creating beds in the hallways, because the regular beds were often full. At times like that, a hospital’s resources get stretched to the limit, and the quality of care may decline, resulting in increased complications, errors, and poorer outcomes. (This is one reason why the State of New Jersey is making a mistake in encouraging hospitals to close, but that will be the subject of another column).

Once a person has the flu, they are infectious one day before symptoms appear and then for five days after that. The diagnosis may be difficult, since the flu can mimic other viral infections. If you are young and healthy, you will likely recover without needing intensive management, but if you are in a high risk group, you need to seek medical attention quickly, especially if you have symptoms beyond a simple cold with a runny nose. You must call your doctor immediately if you have fever, productive cough, chills, severe fatigue, chest pain or shortness of breath. If in doubt, call without delay. A definite diagnosis can be made, if necessary, with a nasal smear, and there are anti-viral drugs available which may reduce the severity of the condition.

Obviously, the best approach is prevention. Most people think of the influenza vaccine (the “flu shot”) when they think of prevention. That vaccine was developed in the 1940’s. It is made using deactivated viruses (dead germs), so there is no chance of catching influenza from a flu shot. The vaccine contains three virus strains, but each year the formula is changed in the hopes of matching the protection to whatever virus emerges in the following season. The vaccine will be most effective if there is a good match, but all formulations will work to a greater or lesser degree. Since the vaccine is made using eggs, people who are allergic to eggs cannot receive a flu shot. Two years ago there was a worrisome shortage of vaccine, but this year there will be enough. A nasal spray vaccine was just approved, but only healthy people can receive it, and its use must be discussed with your doctor.

In the latest issue of the New England Journal of Medicine, a 10 year study from the US and the Netherlands regarding the effectiveness of the flu vaccine in the elderly has provided convincing evidence that influenza vaccinations do substantially reduce hospital admissions due to pneumonia and influenza as well as death rates. But, in an editorial in the same issue, Dr. John Treanor, from the University of Rochester, pointed out that the current flu vaccine is less effective in the elderly than in young healthy individuals, and that many elderly patients will get sick with influenza and die even though they have been vaccinated. Although he hopes for better vaccines in the future, he says that “the [current] vaccine is beneficial and should be used widely.”

It’s best to get a flu shot in early October through November, but the vaccine can be effective at any time during flu season. Once you receive the injection, your body will begin to produce protective antibodies, and the shot will be doing its job within two weeks. Some people get mild side effects from the injection, but serious problems are rare.

The CDC has developed guidelines regarding who should receive the vaccine - www.cdc.gov/flu/protect/keyfacts.htm.

The people who should get vaccinated each year are (per the CDC web site):

1. People at high risk for complications from the flu, including: a. Children aged 6 months until their 5th birthday; b. Pregnant women; c. People 50 years of age and older, and d. People of any age with certain chronic medical conditions; e. People who live in nursing homes and other long term care facilities

2. People who live with or care for those at high risk for complications from flu, including: a. Household contacts of persons at high risk for complications from flu; b. Household contacts and out of home caregivers of children less than 6 months of age (those children too young to be vaccinated); c. Healthcare workers

There are some other considerations with respect to prevention. Dr. Treanor, in his current editorial says, “Influenza cannot develop in elderly persons if they are not exposed to influenza virus from others. Elderly persons have frequent contact with health care workers and others in the health care system. Those people often report to work even when they are not feeling well and can easily serve as vehicles of doom for their unsuspecting patients. This is why the extraordinarily low rates of vaccinations of healthcare workers in the United States are so appalling.” When I was in practice, everyone in our office, including the docs, were vaccinated. Evidently, there is room for improvement in the healthcare field.

We should all keep in mind that influenza is transmitted by droplets introduced into the air via coughing, sneezing or just breathing. The virus projects as far as three feet away from the source, but it doesn’t linger in the air. Try to stay more than three feet away from anyone who might be ill. In fact you might consider running out of the room.

In particular, avoid crowds and high risk places like airplanes. Wearing a face mask might be helpful if you must travel in an airplane or be among people such as children who are coughing and sneezing. Practice frequent hand washing, since you can get the virus by touching infected objects.

Children often transmit viruses to the elderly, and there is some evidence from Japan that vaccinating all children might reduce the infection rate in the elderly. As with so many aspects of medical practice, the more we learn, the more questions we need to answer, so there is no policy at present to vaccinate all children. If you haven’t had your flu shot, and if you are on the recommended list, then call your doctor tomorrow and get the vaccine.

References:

Treanor J.D. Influenza—the goal of control. N Eng J Med 2007; 357:1439-1441.

Nichol KL et al. Effectiveness of influenza vaccine in the community-dwelling elderly. N Eng J Med 2007; 357: 1373-1381

Centers for Disease Control and Prevention (CDC) www.cdc.gov