Understanding flu vaccine - how to make an informed decision.

Influenza, or the flu, is a contagious respiratory viral illness that causes cough, sore throat, runny nose, muscle aches, fever, fatigue etc. While most people with flu are only sick for a few days or a week, the flu can lead to serious complications such as pneumonia, bronchitis or sinus infection. Those at highest risk for complications from the flu are the very young, the very old, or those who have a compromised immune system. The flu virus spreads when an infected person coughs or sneezes droplets into your face. Flu viruses can also survive on commonly touched objects such as phones, doorknobs, or countertops for up to two days. If a person touches these objects and gets the flu virus on their hands, then rubs their mouth, nose or eyes they could become sick with the flu. Hand hygiene is very important in preventing the spread of flu.

Vaccines are designed to protect against the actively circulating and highest risk flu strains. In my experience the flu vaccine is very controversial. It seems there is very little middle ground. Either people are strongly for the vaccine or strongly against it. Hopefully this article will clear up some commonly held misconceptions about the flu shot, and allow you to make an informed decision if the flu shot is right for you.

Why should I get the flu shot?

Flu vaccination can prevent illness among those with chronic health conditions. Flu vaccination resulted in 79% fewer hospitalizations among people with diabetes and 52% fewer hospitalizations among people with chronic lung conditions. Vaccination has also been associated with fewer cardiac events among people with heart conditions.

Flu vaccination protects women and babies during and after pregnancy. One study showed that flu vaccination reduced acute respiratory infection by one half in pregnant women. Other studies have shown that when a pregnant woman is vaccinated against flu, the risk of flu illness in her baby is reduced by half. This protection lasts for several months after birth.

Flu vaccination protects small children. A study published this year showed that flu vaccination reduced the risk of death from flu by 51% in children with underlying high-risk medical conditions, and by 65% among healthy children.

Flu vaccination can prevent spreading flu to vulnerable people. Some people with chronic health conditions do not develop full protection after receiving the flu shot. These people are at risk of severe complications and even death from the flu. If the people they come in contact with have been vaccinated against the flu then they are much less likely to become ill.

Can a flu shot give you the flu?

The flu vaccine is inactivated. It is not a live virus and therefore cannot give a person the flu. In multiple randomized, blinded studies some people were given flu vaccine and others were given saline solution. The participants did not know which they received. The results of the studies showed there was no difference in symptoms of body aches, fever, cough, runny nose, or sore throat between those who received the vaccine and those who received saline. The flu shot can cause redness, soreness, or swelling where the shot was given. In some cases it can also cause mild fever, headache or muscle aches, which resolve quickly. These symptoms are much milder than a flu infection, and typically last only 1 or 2 days.

Is it better to get the flu illness that the flu vaccine?

Influenza can be a very serious illness, especially for young children, older adults, or those with chronic medical conditions. Any flu infection carries the risk of serious complications or death even for an otherwise healthy person. Getting the flu vaccine is much safer than getting the flu.

Why get the flu vaccine every year?

The components of the flu vaccine change with each flu season to protect against the strains that are most likely to cause illness for that specific year. For this reason you should be revaccinated every year so you are protected for this specific season. Occasionally the flu vaccine is the same two years in a row. Even if that is the case it is still recommended to get the flu shot every year because the protection the flu shot offers decreases over time.

Why do some people get the flu vaccine, but still get sick with flu symptoms?

There are several reasons this may happen.

A person may become ill with another respiratory virus such as rhinovirus, which is associated with a common cold, and causes symptoms similar to the flu. The flu vaccine only protects against the influenza virus.
Another possibility is that the person became exposed to the flu shortly after receiving the vaccine and before they had developed full immunity. It takes an average of two weeks after receiving the flu shot to develop full antibody protection.
A person may develop flu symptoms after receiving the vaccine if they were exposed to a strain of flu different than the viruses the vaccine was designed to protect against. There are many different flu strains. Scientists begin research long before the flu season to determine the strains that are most likely to cause illness for the upcoming flu season. The vaccine manufacturers then make the flu shot to protect against those strains. Sometimes a strain of flu circulates that the vaccine does not protect against. If a person is exposed to a flu strain that is not in the vaccine they may become ill. At Arcadia Physicians Travel Clinic we offer the quadrivalient flu vaccine, which protects against four different flu strains.
The final reason a person may become ill after vaccination is that the vaccine varies in its effectiveness. While most people develop full antibody protection after receiving the flu shot, some people who have a compromised immune system may not develop full protection. Small children also may not develop full protection after a single flu shot.

I have been told there are unsafe substances in the flu vaccine. Should I avoid the flu shot?

The flu vaccine has been thoroughly studied over many years and through multiple studies. After many extensive tests, all components of the vaccine have been found to be safe. We provide a vaccine that is preservative free and contains no thimerosal. The vaccine contains small traces of antibiotic equal to 0.00000003 of a typical daily dose, which is very safe.

The CDC recommends that with rare exceptions everyone over 6 months of age should receive the flu shot, but only you can decide whether the flu shot is right for you.