Everything You Ever Wanted to Know About the Flu Shot, Answered

The flu season is in its early stages, and millions of Americans are making sure they’re as protected as possible with a flu shot. Every year, Lehigh Valley Health Network (LVHN), part of Jefferson Health, makes getting a flu shot more convenient for area residents by administering free seasonal flu vaccinations for adults and children 6 months and older. This year, the organization will hold community drive-thru flu shot sessions on Nov. 7 and Nov. 8. Learn more and complete a consent form here.

People often have concerns about flu shots, so we took the opportunity to address common questions with Brenda Croll-Stachelek, RN, Jefferson Health-Regional Director of Infection Control.

Croll-Stachelek: Scientists and vaccine manufacturers study what is circulating regarding the flu virus in the southern hemisphere because it’s a season ahead of us. Determinations are then made as to what to put in this year’s vaccine. The vaccine is formulated each year because the circulating virus strain may change each year.

The Centers for Disease Control and Prevention (CDC) conducts studies each year to determine how well the flu vaccine protects against flu illness. While vaccine effectiveness can vary, recent studies show vaccine reduces the risk for flu illness by 40% to 60% among the overall population during seasons when most circulating flu viruses are like the vaccine viruses.

Croll-Stachelek: We offer two types of vaccine at the community drive-thru campaigns. One is a standard dose for people 6 months of age to 64. The other is the high-dose vaccine for people 65 and older. Some people are concerned with the thought of a higher dose, but the purpose of the high-dose vaccine is to assist in stimulating the immune system of someone whose system may not function as well as when they were younger.

Croll-Stachelek: We do not offer the nasal spray vaccine (live, attenuated influenza vaccine) at LVHN drive-thru clinics.

According to the CDC, the nasal spray flu vaccine is approved for use in people ages 2 through 49. People should not receive the nasal spray flu vaccine if they have ever had a severe allergic reaction to any influenza vaccine, are pregnant, or have certain medical conditions. Please consult with your primary care clinician for more information. 

Croll-Stachelek: Yes. The flu virus mutates rapidly from year to year. The vaccine is updated annually to match the strains expected to spread during the current season. The immunity your body builds from a previous flu shot or natural infection declines over time and typically lasts about six months.

Even if you are young and healthy, getting vaccinated reduces the likelihood that you will contract the virus and pass it to others. This provides a layer of protection for highly vulnerable populations who can face life-threatening flu complications.

While a healthy immune system reduces your risk, it does not guarantee a mild illness. Healthy children and adults are still hospitalized or face serious secondary infections (such as pneumonia) from the flu, and thousands of people – young and old – die each year due to influenza.

Croll-Stachelek: Yes, including people who have severe allergies to a component within the vaccine. They should consult with their primary care clinician or an allergist to find out if there is a vaccine that can be given more safely in a controlled environment. Individuals who have had a severe reaction to a flu shot in the past or a history of Guillain-Barre syndrome (a condition in which the immune system attacks the nerves) should be evaluated by a physician before getting a flu shot.

Croll-Stachelek: You might get an achy arm, perhaps some redness in the injection area, and maybe even a low-grade fever in isolated cases. Normally, they’re all short-term effects. If the area becomes itchy or if hives develop, these would not be considered normal reactions, and you should see a clinician. More extreme reactions – throat constriction, shortness of breath, or dizziness – would require an emergency room visit. But these abnormal reactions are rare.

An achy arm can be a good sign: it means your body is reacting to the antigen and developing antibodies to help protect you from the flu virus. Some tips to help you from getting a sore arm include:

• Relax your arm when getting the injection
• Use your arm after the shot to improve circulation in the area
• Put ice on the injection area the first day and then warm compresses the next day
• Consider taking an over-the-counter pain reliever

Croll-Stachelek: A flu shot can’t cause the flu. The vaccine in flu shots uses inactivated or killed viruses. It generally takes about two weeks for the flu vaccine to work. Therefore, if you develop upper respiratory-type symptoms following the flu shot, you were already exposed. People frequently confuse a cold and the flu because there are some similarities in how they make you feel.

If you’re wondering whether it’s just a cold, Croll-Stachelek offers this distinction: Symptoms of the flu can include fever or feeling feverish, chills, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches, and fatigue. Cold symptoms usually are milder. People with colds are more likely to have a runny or stuffy nose, and colds generally do not result in serious health problems.