Insights to Influenza

Patients often inquire as to why there is a recommendation to get an influenza immunization each year.

Let’s answer this question by first trying to clear up some of the confusion caused by the terms influenza and “flu”.  Influenza is a specific respiratory illness caused by a virus named influenza.  The term “flu” is commonly used to describe many different illnesses, some with cough, some with diarrhea, some with fever or rash.  Influenza is a single illness caused by the influenza viruses and “flu” means any of a number of different illnesses.  Influenza and “flu” are not the same thing.  If we understand this then we will understand why confusion exists regarding the effectiveness of the influenza vaccine and the seriousness of the illness.

Here is a little information about the virus causing influenza. This virus circulates among humans and some animals all over the world.  As it is spreading and causing illness it slowly changes or mutates.  The result is similar to what happens by mating different dog breeds.  The result is a dog with different traits and/or appearance. As these viruses change or mutate they are no longer recognizable by the immune system of someone infected or immunized in the past.  As a result each year many people are susceptible and can be re-infected.

The illness we call Influenza is a memorable illness for most who are infected. It causes high fever, lots of muscle aches, headache, sore throat, cough, and nasal congestion.  Some may have diarrhea but it is primarily an infection of the respiratory tract lasting 5-7 days.  It is far worse than a common cold and most illnesses we often call the “flu”.  Some who get influenza will develop serious complications such as pneumonia putting them at risk of hospitalization and even death. We know that each winter there are many excess office and emergency room visits, hospitalizations and deaths due to influenza.  Because of this it makes sense to try to prevent this infection. 

To try to prevent infection each year researchers try to predict the changes occurring in this virus and develop a vaccine to protect us from infection.  By getting the vaccine you protect yourself from infection and illness, and you are less likely to spread the illness to others.  As a result many fewer are infected and become ill.   So immunization against influenza is not only a preventative technique it also saves all of us health care costs.  However, often we hear people say they got the influenza vaccine but still got the “flu” or that the vaccine made them ill.  What happens most commonly is that they did not get influenza but did get “flu” like illness but interpreted this as influenza.  This is a mistake and the source of much confusion. Potentially we can prevent a lot of influenza but we can’t prevent all “flu” illnesses.

The influenza vaccine is so safe and effective that it is now recommended for everyone over 6 months of age except a few of us with egg allergy.  This includes pregnant women as we now know this prevents potential complications if a woman gets influenza during pregnancy and it is safe for the baby.  In addition it protects the infant after birth for several months.  For children ages 6 months through 8 years who have not received an influenza vaccine since 2010 this year it will require two doses of vaccine a month apart.  

The influenza season is approaching so get your vaccine as soon as possible.   Remember the vaccine is much safer than the illness; and influenza is far more serious than most illnesses we refer to as “flu.”

This is Dr Woodard.  Have a good day.

Dr Woodard is physician and owner of Alaska Center for Pediatrics