In a year that has been dominated by uncertainty from a “novel” virus, one thing that is for sure is that the influenza virus will be making its appearance in the coming weeks. It is important to remember that influenza kills otherwise healthy adults and children each and every year. In the 2019-2020 flu season, 188 children died from the flu with over 50 percent of these children having no underlying medical conditions. 

While most of our attention has been focused on COVID, we must not forget to give Influenza its due and realize that we DO have a vaccine that can prevent this viral infection. Read on to find out what parents have been asking me in regard to flu and what will make this flu season different.

How will doctors know if someone has influenza or COVID?
This is a question that keeps me up at night already! Since both of these illnesses are respiratory viruses, common symptoms will be fever, cough, body aches, and chills. COVID can often present with the distinctive loss of taste or smell, which is not something commonly seen with influenza. Influenza has a much shorter incubation period, meaning that after an exposure, someone would likely show symptoms within 1-4 days, as opposed to COVID, which has an incubation period of 2-14 days. The only way physicians are really going to be able to tell if someone has COVID or the flu is through testing.  

When does flu season start?
Influenza is a virus that we often see starting in late fall or early winter and lingering into the early spring. One of the tough things about Influenza is that you never know when a season will begin. Here in Louisiana, we are notorious for starting our flu season off early, often becoming one of the first states in the Nation to have elevated flu numbers. The unpredictability of when flu season will start is one of the main reasons that getting your flu vaccine as soon as possible is critical.

Can you predict if the flu season will be “bad?”
There are many times in medicine that a crystal ball would be helpful, and one of those times would be predicting the severity of a flu season. How severe a flu season will be here in the US depends on so many factors, including what strains of flu are the predominant circulating strain, how many people have been vaccinated, as well as how good of a match the flu vaccine will be. Scientists often look to places in the Southern hemisphere to see how their flu seasons have gone, as this part of the world is just finishing up their flu seasons when our flu season in the US is about to get underway. So a little bit of good news…the Southern hemisphere has had a VERY mild flu season! This is likely due to social distancing measures, masking mandates and other COVID-19 mitigation strategies that have been put into place in these areas. However, I am hopeful that given our COVID-19 mitigation strategies in place here in the US, that we will also see a quieter flu season.

Who needs a flu vaccine?
Everyone six months of age and older needs a flu vaccine each and every year. The composition of the flu vaccine changes each season (see below) which is why getting the vaccine each year is key.  For children six months through eight years of age who have only received one flu vaccine prior to July 2020, they should receive two flu vaccines this fall (four weeks between the vaccine doses). For those 65 years of age and older, there is a high dose flu vaccine available that contains four times the antigen (the part of the vaccine that gives your body protection from the virus) to hopefully provide additional protection for this older population.  

What should I know about the available flu vaccines this year?
The available flu vaccines for the 2020-2021 flu season will have four strains of flu protection (called quadrivalent vaccines). The two strains of influenza A and one of the influenza B strains covered are updated in this year’s vaccine. These updates are made based on the flu strains seen during the last flu season and what we are expecting to see this year. The remaining influenza B strain is the same from last year’s vaccine. Both the injection and nasal mist spray will be available this year, and there is no preference for shot or mist this year.  Remember that the flu mist nasal spray is only for those two years of age and older who have no underlying asthma or lung issues and have a normal functioning immune system, as it is a live-virus vaccine.

I have gotten the flu vaccine in the past, and I still ended up getting the flu! How does that happen?
Unfortunately, the flu vaccine will never be perfect. Each year, the composition of the flu vaccine changes depending on what strains of influenza scientists expect to circulate during the flu season. 

“Expect” is the key word here as there is no way to 100 percent know which version of the virus we will see until we are deep into the flu season. Scientists have to make decisions about flu vaccine composition in February so that vaccines can be produced and ready for the fall. This would be like trying to predict who will play for the college football national championship months before the football season even started. There is a high likelihood that the prediction might not even be in the correct conference! 

However, even with the possibility that the flu vaccine might not be a perfect match for the circulating flu strain, any protection from influenza is better than none at all. When looking at the pediatric deaths during the 2019-2020 flu season, almost 75 percent of those children who died were unvaccinated for influenza. It is important to realize that the flu vaccine is not a guarantee that you won’t get the flu, but it will absolutely decrease the chance of serious illness, hospitalization or death from influenza. 

This fall and winter respiratory season will be unlike any other for physicians. In a year that has brought so much unpredictability for all of us, we need to do everything we can to keep from having two circulating pandemics. I encourage everyone to get your flu vaccine as soon as possible (but absolutely before the end of October), continue with good hand hygiene practices, and wear your mask when unable to keep your distance from others. Let’s try to keep ourselves, our families, and those around us as healthy as possible during this flu season.

Mindy L. Calandro, MD, FAAP