The Centers for Disease Control and Prevention (CDC) says the seasonal flu shot is 40 to 60% effective in preventing the flu. However, timing your vaccine properly is important to maximizing its efficiency, so when is the best time to get a flu shot?

Should I Get My Flu Shot in the Fall?

Craig P. Chase, M.D., a partner at Oviedo Medical Research, confirms that fall is the best time to obtain your yearly flu shot. 

He says, “The CDC recommends, and we’ve always recommended that the first part of October is probably the best time to get the flu vaccine in Florida.”

Unlike other vaccines that provide longer-lasting immunity, the flu vaccine varies from year to year. That’s because flu viruses mutate constantly. You can’t get the flu vaccine this year and expect it to last next year. The vaccine has to change every year to keep up with the ever-changing nature of these viruses. 

How Does the Flu Vaccine Work?

The flu shot works to protect you from the three most common types of flu anticipated that year. The vaccine contains deactivated strains of the flu types that research shows will be the most common circulating that year. The flu vaccine works by giving your immune system the chance to fight off an altered version of these viruses so that when you encounter the live virus your body will already be immune. Even if the immunization doesn’t protect you from getting the flu, the chances are greater that you will be less seriously ill if you pick up a virus.

Getting a flu shot is your best bet for shoring up immunity against the most common strains of influenza this season. Influenza is a type of respiratory illness transmitted through viruses. It is in this way that influenza is similar to COVID-19, although the influenza virus is different in form from the coronavirus, which causes COVID-19. 

While the influenza virus is not 100% effective in preventing the flu, you stand a much better chance if you have it as a preventative treatment. The Mayo Clinic says, “Reviews of past studies have found that the flu vaccine is about 50% to 60% effective for healthy adults who are between 18 and 64 years old.” 

What’s Inside a Flu Shot?

The flu shot contains:

  • Antibiotics in very small amounts, which keep bacteria from contaminating the vaccine
  • Egg protein, leftover from the fertilized chicken eggs where the viruses have been grown
  • Formaldehyde in small amounts, which is a natural product found in adhesives
  • Inactivated viruses that have been killed and cannot cause the flu
  • Polysorbate 80, which is the same product that keeps sauces and salad dressings from separating
  • Stabilizers that include sugars (sucrose, sorbitol) and monosodium glutamate (MSG)
  • Thimerosal, a preservative 

While there has been controversy surrounding the flu shot, the additional ingredients to preserve the inactivated flu vaccine are in tiny amounts that cause no harm to humans. While you can experience a fever or fatigue after the shot, other side effects are exceedingly rare.

How Effective is the Flu Vaccine?

The flu virus mutates each year, so our effectiveness in predicting the right strain of the virus ranges between 40% to 60%. Key to maximizing its effectiveness is to get your vaccine at exactly the right time. 

Dr. Chase cautions against getting the shot too early; October is the perfect month to receive your vaccine because, “It’ll catch you before we really start to see flu, which really comes at the end of October/November. You don’t want to get it too early and have your immunity wear off before you get to the meat of the flu season.” 

Healthline states, “A yearly flu vaccine is the single best way to prevent the flu and its complications.” Although the effectiveness of the vaccine each year can vary, these inoculations have done a nice job reducing illness and doctor visits or hospitalizations. For example, during the 2016/2017 flu season, the flu vaccine prevented 2.6 million clinical visits and 5.6 million illnesses.

Who Should Get a Flu Shot?

Each year, flu vaccines prevent illness, hospitalizations, and even death. Everyone can benefit from the vaccine but it’s critical for high-risk groups. Getting the flu can cause serious and even life-threatening complications such as:

  • Bronchitis
  • Ear infections
  • Pneumonia
  • Sinus infections

People suffering from chronic health conditions, older adults, pregnant women, and healthcare workers should always get an annual flu shot, unless they have complicating factors such as allergies to the ingredients. Very young people have an increased risk of developing flu complications, however the vaccine is not recommended for those under six months of age. If you have a weakened immune system you should get the shot. Or, if you live in assisted care or a nursing home.

Dr. Chase urges everyone in these categories to seek out a flu shot this year, particularly with COVID-19 a potential complicating factor. He states, “In Florida, probably January through March is our biggest flu season. That’s when the cases really start going up.” Getting a flu shot now is your best way to prevent dangerous illness this fall and winter.

While the flu shot is a personal decision, today’s influenza season coupled with the COVID-19 pandemic creates additional concerns. The addition of a second respiratory illness like the seasonal flu on top of the COVID-19 pandemic could overwhelm health care systems. It is possible to catch COVID-19 and the flu simultaneously, which is a concern.

For COVID-19 and the flu, those with underlying conditions and the elderly are at greater risk. The more people that get the flu vaccine, the more protected everyone will be. Oviedo Medical Research specializes in Phase II – IV clinical trials that yield the medications and vaccines doctors use to take care of your health. If you’re interested in joining us for a clinical trial, contact us.