How long does the flu shot last?

Doctor's advice / Sanitas Medical Center

Date: October 28, 2021
How long does the flu shot last?

What is flu?

Flu is the common term used to describe the infection caused by the influenza virus in humans. It is a contagious respiratory illness that can be mild (like a common cold) or can be severe, affecting the throat and even the lungs. Sometimes when the lungs are very compromised, flu (influenza virus infection) can lead to death.

Although the flu can initially show up as a common cold, these are two different diseases. People who develop flu usually have fever, cough, sore throat, body pain, headache, and tiredness. Some people, especially those with mild infection, may have only a few symptoms.

Who can get infected with the flu virus?

Flu viruses mainly spread by tiny (almost invisible) droplets in the air. These droplets appear when infected people cough, sneeze or even talk. Many viruses spread in the same way, including the one causing COVID-19. When these droplets touch another people mouth, nose or eyes, they get infected. A less common way of getting the infection is by people touching any surface that has the virus on it, and then touching their own faces, mouth, nose or eyes.

Scientists and doctors from the Centers for Disease Control and Prevention (CDC) have studied the flu virus from long ago. They work hard to control and prevent Influenza outbreaks, promoting awareness among population. Although anybody can get a flu, and severe and serious problems related to it can happen at any age to anyone, some people are at high risk for the development of flu complications. They include:

  • People over 65 years
  • People with previous chronic medical conditions (such as Diabetes, Asthma or heart diseases)
  • Pregnant women
  • Children younger than 5 years

Complications can range from pneumonia, dehydration and ear or sinus infections, to death itself.

Are there different types of flu?

There are several flu types that occur worldwide. The best known types of influenza are the Swine flu and the Avian flu. These are caused by Influenza viruses that naturally infect animals (pigs for the Swine flu and birds for the Avian flu), that normally don’t cause diseases in humans; however, sporadic infections may occur.

The most common types of influenza are the seasonal influenza, and the pandemic influenza. During fall, winter and spring, Influenza viruses peak their circulation among people. This is called the flu season. In the United States, the flu season typically occurs from October to May, but its duration depends on each year’s trends.

A pandemic influenza is a global outbreak of an Influenza virus, and happens when a flu virus mutates (changes its composition). The last influenza pandemic occurred during 2009, and it was caused by a Swine flu virus.

How can I prevent the flu?

Influenza viruses (like all viruses) constantly change (mutate). This characteristic has made the Food and Drug Administration (FDA) to evaluate flu vaccines periodically. Each vaccine is reviewed and updated annually to match circulating seasonal flu viruses.

As of today, the flu shot is the best preventive action anyone can take against getting the flu. Therefore, the CDC recommends vaccination in every 6 months and older person to prevent the seasonal flu. This is especially important for people who has higher risks of complications.

Which vaccine should I choose?

CDC is recommending to vaccinate for the 2021 flu season since September, and ideally, everyone should be vaccinated by the end of October.

Like with COVID-19, any FDA licensed and approved vaccine in the US is considered appropriate, and no manufacturer is recommended over another. All vaccinations highly reduce the risk of severe illness and complications in a similar way.

Are there any adverse effects of vaccinations?

One of the biggest myths about vaccinations, especially flu shots, is that they are not safe. This has proven to be false. Although immunizations, like medications, can produce adverse effects, those are very unlikely to appear. Vaccines are generally safe for the biggest proportion of the general population, and their benefits extend far beyond the possible risks.

Flu shots does not give people the flu, as they consist of dead or inactivated strains of the virus. It is scientifically impossible for the shot to give someone the infection. Potential side effects from the flu vaccine include self-limited symptoms like:

  • Redness, swelling, or soreness at the injection site
  • Low-grade fever
  • Headache
  • Nausea
  • General aches and pains

It is important for you to know that not everyone develops side effects, and that, in case you develop any, they are typically mild and only last a few days.

When should I revaccinate against flu?

The vaccine protects everyone who is vaccinated from a severe infection for the duration of the current season. Protection lasts around 6 to 8 months, starting two weeks after you receive the vaccine.

Once the season ends, the flu shot does not protect you any longer: you will need a new vaccination for the following year’s season. In fact, you should get the shot with the current season’s vaccines the FDA approves yearly.

At Sanitas, we offer you the latest flu shot approved by the FDA during the whole season, including the last months. What is most important for us is to keep you healthy by offering preventive measures such as vaccines for different diseases, and giving health advice. Ask your doctor for the Flu shot. Prevent flu today. Book an appointment online or call 1-800-888-8888 today!