“I got the flu shot and still got sick! What’s the use?”
You may be feeling a bit skeptical about getting the flu vaccine when you’ve had flu, even after being vaccinated.
But here’s the thing! If you ended up sick despite the shot, it could be because you were exposed to a viral strain not covered by the vaccine. Or, perhaps, it was another sneaky reason!
Let’s clear up some common misunderstandings and help you feel more confident this flu season. In this blog, you’ll not only explore the safety and effectiveness of vaccines but also dive into the reasons behind getting sick after a flu shot.
Keep reading to explore further insights on why it is important to get vaccinated every year. Let’s get right into it!
Are Flu Shots Safe And Effective?
Yes, flu vaccines are considered safe and effective as they undergo strict surveillance in clinical trials to determine their safety in people of different ages.
According to the CDC, people who have received a flu shot are 40% to 60% less likely to get flu. The effectiveness of flu vaccines varies every year because the influenza virus strains change over time.
Therefore, getting yourself and your family vaccinated before peak cold and flu season can reduce your risk of developing severe complications such as pneumonia and prevent the worsening of existing conditions.
Can a Flu Shot Make You Feel Sick?
Yes, you may feel lethargic and tired after a flu shot, but the symptoms would be mild and go away on their own within a few days.
Although it’s rare, some people also experience a low-grade fever after getting a flu shot, which will improve once they take a fever-relieving medicine.
This is because flu vaccines contain an inactivated or weakened form of the virus to trigger the generation of antibodies. When your immune system activates, the antibodies try to fight the foreign weakened or inactivated viruses (also known as antigens), and in response, you experience fever or fatigue.
If you come in contact with the flu virus in the future, you’ll have strong immunity as the antibodies will automatically fight against it.
Can You Catch Flu After A Flu Shot?
The idea that you can catch the flu after receiving a flu shot is a common misconception. Note that the vaccine itself does not cause flu.
This is because the vaccine consists of inactivated or dead viral proteins or antigens that cannot infect you.
However, if you still catch the flu after receiving the vaccine, it can be due to the body’s immune response as it prepares to defend against the actual virus.
Moreover, the body takes almost two weeks to develop immunity against the influenza virus. If you’re exposed to the virus right after receiving the vaccine, it may be possible that you would have flu symptoms.
Also, other viruses circulate during the cold and flu season. Therefore, catching a cold or another viral infection caused by other viruses, such as coronavirus, rhinovirus, respiratory syncytial virus, etc, is possible.
Three Possibilities Why Flu Shots Make You Feel Sick
Curious about some other potential reasons why you may catch the flu even after the vaccine? Let’s dive right in!
1. The strain has been mutated and isn’t present in the vaccine
The flu vaccine takes almost four months to produce. During the production of the flu vaccine, scientists have to make early guesses and decide which flu strain is going to be the most prevalent in the upcoming flu season.
Since the influenza virus mutates at a faster rate, it can even change some of its structure during the production phase.
To be on the safer side, the flu vaccine protects you against three to four specific strains of influenza. These are selected after detailed research and analysis of the past prevalent strains.
Despite their best guesses, the flu virus can mutate multiple times in a year, and the vaccine may fail to provide immunity against the prevalent influenza strain.
2. The immune system is not fully developed
You can still get the flu if your immune system is not fully developed to protect against the virus. This can happen in the following scenarios:
- You have any other condition such as diabetes or heart disease which has weakened your immune system.
- You may have a different viral infection such as the common cold, pneumonia or bronchitis.
- You were vaccinated too late and your body didn’t have enough time to develop full immunity.
Even if you relate with any of the following above, you would be less prone to develop flu-related complications as the vaccine produces antibodies that protect you in the future.
3. You’re older than 65 years of age
People older than 65 have less immunity and are at the highest risk of developing flu-related complications.
Therefore, the CDC and federal health officials recommend that older people get higher doses of flu vaccine to better protect themselves against the rising flu virus.
If you’re over 65 years old and are concerned about which flu shot to receive, a nearby urgent care clinic would help you pick the vaccine that is best suited for your age.
Why Is It Important To Get Vaccinated Every Year?
You might be thinking, ‘If I could still catch the flu after receiving the shot, why should I take it then?’ Well, that’s like saying, ‘If I can get sick again, why take the medicines in the first place?’
‘Receiving a flu vaccine reduces the chances of catching the flu and also lowers the risk of serious illnesses,’ says Dr. Asrar Sheikh, MD, at Family Urgent Care.
Several studies back this claim! A review article published in 2023 reports that getting a flu vaccine can reduce the risk of flu-associated hospitalization by 29% and the risk of death by 18%.
Also, the CDC reported that in 2019-2020, flu shots helped prevent 100,000 flu-related hospitalizations.
Therefore, the CDC recommends receiving the shot yearly to protect yourself and your family from the influenza virus. Even if you catch the flu, the severity of the illness will be far reduced.
Not to mention, influenza virus strains keep changing every year as they get mutated. Therefore, scientists update the flu vaccines from one season to the next to protect you from the newer prevailing strains.
Possible Side Effects in Adults and Children After The Flu Shot
Although the side effects are quite rare, they can occur in some people. The side effects are the same in adults, babies and children, and some of them include:
- Pain and soreness at the site of injection
- Feeling tired, fatigued and experiencing muscle aches
- Headaches
- Mild fever typically 101 F
These symptoms are mostly mild and typically wear off within a day or two. Some people also experience flu-like symptoms as the body prepares itself for the viral attack by producing antibodies.
Not to mention, vaccines can also cause severe allergic reactions but it’s estimated to affect fewer than two people for every 1 million doses. The common allergic symptoms include:
- Difficulty in breathing
- Hives
- Swelling lips and eyes
- Palpitations (fast heartbeat)
- Dizziness
If anyone around you experiences these symptoms, immediately call 911 and take the person to an emergency care facility.
What Is The Best Time To Get A Flu Shot?
September and October are The best times to get a flu vaccine this year. Ideally, the CDC recommends getting vaccinated by the end of October before the cold season starts. Also, the flu shot is effective for one influenza season, which means that next year, you will need another flu vaccine to be fully immunized.
Can Urgent Care Help You Get A Flu Shot?
Yes, urgent care clinics can help you and your family get flu shots the same day you book an appointment. Or you can even walk into the clinic right away if you’re driving nearby.
If you live near Indiana or Illinois, you can also visit Family Urgent Care in a location nearer to your house. We operate in three locations: Halsted, Morse, and Schererville.
Also, if you’re feeling under the weather and experiencing symptoms like a sore throat, headache, fever, or cough, our healthcare providers will provide you with the best care.
So, don’t hesitate to contact us and receive the flu shots beforehand to prepare for the upcoming winter season.