Each year, many individuals are torn between getting a flu shot or not. The situation got more complicated in 2006 when the Centers for Disease Control and Prevention (CDC) recommended that all children six months of age and older receive annual flu shots. Now parents must decide for their children as well.

The influenza virus rears its ugly head every year and results in approximately 36,000 deaths, more than any other vaccine-preventable disease, according to the CDC. Most of these casualties are elderly people but some are children, and many under one year of age are hospitalized. Annual vaccinations are one way to prevent the disease, caused by the influenza virus which constantly changes into a new form from year to year.

Types of vaccines, their effectiveness and side effects

The inactivated (killed virus) vaccine has been around the longest and is given as a shot to anyone aged, six months and up. This vaccine is considered to be 70-90 percent effective in healthy children. The flu shot may cause a mild local reaction with redness or soreness, lasting one or two days, in 15-20 percent of individuals. Less than one percent experience fever, chills and muscle aches.

The second choice is the live, attenuated (weakened) vaccine that is given as a nasal spray but cannot be used on children younger than two years of age. The spray vaccine is about 87 percent effective in healthy children, 5-7 years of age. Some potential side effects include runny nose, nasal congestion, fever, headache, muscle aches, abdominal pain or vomiting.

Neither shot nor spray should be used on individuals with severe egg allergy. Children with weakened immune systems due to chronic medical conditions should not get the spray vaccine.

Concerns about flu shots

Some flu vaccines contain thimerosal, a preservative with mercury, which some people believe is linked to developmental problems, such as autism. You can request vaccines, free of this ingredient, which are available in greater quantities this year. The CDC continues to recommend vaccines with or without the preservative. Some minor reactions, like redness or swelling, at the injection site may occur with thimerosal.

One study indicates that flu vaccines may be ineffective for children, aged five years and under. During the past two flu seasons, vaccination did not reduce the number of children’s hospital or doctors’ visits, according to a study of 414 children, done by the University of Rochester, School of Medicine and Dentistry, and Strong Memorial Hospital, in Rochester, New York. One possible explanation for the lack of effectiveness could be a poor match between the circulating virus and the vaccine.

The study concluded that the inactivated virus doesn’t work well in children, whereas the live attenuated vaccine, given as a nasal spray is far more effective. However, the nasal spray can only be given to children and adults, ages 2-49, without asthma or recurring wheezing.

Children six months and younger

Flu vaccines cannot be given to infants under six months. The CDC recommends that parents and other caregivers get vaccinated in an effort to protect infants from contracting the flu.