Flu Season: What You Need to Know
By Amy E. Hackmann, MD

January 30, 2020
(Originally published on February 28, 2019)



Influenza, or “the flu,” is a group of viruses that cause respiratory symptoms such as high fever, body aches, cough, sore throat, and nasal congestion. This illness is extremely contagious and is most commonly spread through contact with a sick person. If you are exposed to the flu virus (it can spread to others up to about 6 feet away) and you become infected, you will experience symptoms within 1 to 4 days.

Just because you are young and healthy doesn’t mean you do not need to be concerned about the risk of the flu. In 2009, the emergence of the H1N1 influenza virus caused the first flu pandemic in 40 years, involving an estimated 60 million people in the United States. The strain of flu that season affected young, healthy people more than others. According to the Centers for Disease Control and Prevention, 2018 also was a record-breaking year, with an estimated 80,000 Americans dying from the flu, including nearly 200 children.

As a cardiothoracic surgeon, I care for patients who have become very sick with the flu. In a small percentage of patients, the lungs become so inflamed or filled with fluid that they can no longer deliver oxygen to the body. When this happens, treatment may include intubation (a breathing tube and breathing machine). In extreme cases, patients require a special type of heart-lung machine called ECMO (extracorporeal membrane oxygenation) or ECLS (extracorporeal life support). A cardiothoracic surgeon often performs the operation to place a patient on the ECMO machine. Sometimes, lung damage from the flu may be so severe that a lung transplant is required.

Published with permission from the University of Southern California

During the 2009-2010 season, 600 Americans required ECMO for the flu, with the average age being 34 years old. Approximately 25% also had kidney failure and needed dialysis. Half of those people died from the flu and its complications. This flu season also is predicted to be quite severe.  The most deadly strains of influenza virus are included in the vaccine every year, making the likelihood of severe illness very low in vaccinated individuals.

Nearly everyone can receive an influenza vaccine or flu shot from their primary care provider or from a walk-in clinic/pharmacy. The vaccine is made from killed virus, so it is not possible to catch the flu from the shot. Some people experience soreness at the injection site or low-grade fever, which is a sign that your body is building immunity against the viruses. Occasionally, the strains of influenza virus contained in the vaccine are different than the common types in a year, so the vaccine is not 100% effective. However, it is likely that your symptoms will be less severe and last a shorter period of time because of the flu shot. Flu shots should be received every year, usually in the fall. It is not too late to get your flu shot today!

The opinions expressed in this article are those of the author and do not necessarily reflect the views of The Society of Thoracic Surgeons.

The Society of Thoracic Surgeons

The STS mission is to advance cardiothoracic surgeons’ delivery of the highest quality patient care through collaboration, education, research, and advocacy.