The Medical Minute: New flu vaccine recommendations

Flu vaccine is only about 80 percent effective at preventing the flu. That's really not too bad for a vaccine. If only a small percentage of people in a community have 80 percent immunity, the flu can still cause a lot of illness. If everyone in a community has 80 percent immunity, there will be very little flu since everyone will be able to resist it and will be less likely to spread the flu.

So who should get a flu shot? Well, anyone may get one as long as he or she does not have an anaphylactic reaction to egg, that is, stops breathing or gets a swollen tongue or throat when egg is consumed. Since flu vaccine is produced in eggs, there might be a trace of egg protein present, although it's really a very tiny amount.

That limitation aside, people from age 5 to age 50 who are healthy and not pregnant and are not caretakers for someone with chronic medical problems can skip the flu shot if they want. However, getting a flu shot minimizes that person's chance of being ill and missing work or school and reduces the amount of flu in the community that can spread to higher-risk individuals.

Pretty much everyone else should be immunized. That includes children from age 6 months to 5 years, adults over age 50, anyone who will be pregnant during flu season and anyone with such chronic medical problems as diabetes, heart and lung disorders, blood disorders, HIV or other reasons for a suppressed immunity or who lives in a long-term care facility. Also any household contacts or caretakers of people in these groups should have an annual flu shot to reduce the chance of spreading the flu to them. Besides the shot, the nasal spray version continues to be available, but it is approved only for healthy people between ages 5 and 49 years of age.

Why all the concern about immunizing people? Because the flu can be deadly -- not by itself, usually, but because it leads to pneumonia, heart failure and can worsen asthma and emphysema. Perhaps 200,000 people are hospitalized annually from flu complications and as many as 36,000 people die from the flu -- about 8 percent of deaths during the winter.

There should be about 100 million doses available -- enough to cover one in three Americans. The best time to be immunized is October and November because the flu usually does not get to the United States until December and it takes about two weeks to develop immunity. Children who have never had a flu immunization need two doses four weeks apart the first time. Adults need only one dose.

Flu vaccine does not cause illness -- it can't because the virus is dead in the case of the injection and the virus in the nasal spray version is changed so it stays in the nose and does not lead to disease in the body. However, the very first time someone receives a flu shot, that person's immune system thinks there is an infection and responds accordingly. This can cause a little achiness or low fever for a day or two, but since there is no infection, it goes away. In subsequent years, that reaction should not happen.

Flu vaccine does not prevent colds, which are very different from the flu. Also, the flu vaccine physicians and others will be administering has nothing to do with the avian flu, which has not been seen in North America and is not yet a disease that we must worry about.

Most insurance companies will cover the cost of flu vaccine, at least for those for whom it is recommended. Many pharmacies and community organizations administer flu vaccine at reasonable cost. Full price for the injectable version should be about $25 and for the nasal spray, perhaps $40-50 per dose.

So, this year there's almost no reason not to get flu vaccine. Read more about the flu and flu vaccine at the CDC Web site at http://www.cdc.gov/flu/ online.

Source: By John Messmer, Penn State Family and Community Medicine, Penn State College of Medicine