Can You Get the Flu After Vaccination?
know about the flu vaccination, risk of flu post-vaccination, why vaccination may not work and when you should see doctor and get vaccination done and more.
Written by Dr. D Bhanu Prakash
Reviewed by Dr. Shaik Abdul Kalam MD (Physician)
Last updated on 18th Oct, 2025
Introduction
Getting a flu shot is one of the best ways to protect yourself from the flu, but you might wonder—can you still get the flu after vaccination? The short answer is yes, but there’s more to it. Let’s break it down in simple terms so you can stay informed and take the right steps to stay healthy.
Why Does the Flu Vaccine Not Always Work?
The flu vaccine is designed to protect you against the most common strains of the influenza virus expected in a given season. However, a few reasons explain why you might still get sick:
1. Virus Strains Change – The flu virus mutates frequently. Scientists predict which strains will be most active each year, but if a different strain circulates, the vaccine may not fully protect you.
2. Time for Immunity to Build – It takes about two weeks after vaccination for your body to develop immunity. If you’re exposed to the flu during this window, you could still get sick.
3. Weakened Immune Response – Older adults, young children, and people with chronic illnesses may not develop strong immunity even after vaccination.
4. Vaccine Effectiveness Varies – No vaccine is 100% effective. On average, the flu shot reduces the risk of illness by 40-60%, but it still lowers the severity if you do get sick.
Consult a top general practitioner for the best advice
What Are the Chances of Getting the Flu After Vaccination?
While the flu vaccine doesn’t guarantee complete protection, it significantly reduces your risk. Here’s what research shows:
If you get vaccinated, you’re 40-60% less likely to catch the flu.
Even if you do get sick, symptoms are usually milder and recovery is faster.
The vaccine lowers the risk of severe complications like pneumonia or hospitalization.
Can the Flu Shot Give You the Flu?
No, the flu shot cannot give you the flu. The vaccine contains either:
Inactivated (dead) virus (in the injectable flu shot)
Weakened live virus (in the nasal spray, but it doesn’t cause illness)
Some people may experience mild side effects like:
Soreness at the injection site
Low-grade fever
Mild body aches
These symptoms are not the flu—they’re signs your immune system is responding to the vaccine.
How to Reduce Your Risk of Getting the Flu?
Even after vaccination, take these extra precautions:
Wash Hands Frequently – Use soap and water or hand sanitizer.
Avoid Close Contact with Sick People – Stay at least 3 feet away from those coughing or sneezing.
Boost Your Immunity – Eat a balanced diet, exercise, and get enough sleep.
Stay Home If You’re Sick – Prevent spreading the virus to others.
When to See a Doctor?
If you experience severe flu symptoms despite vaccination, consult a doctor, especially if you have:
High fever lasting more than 3 days
Difficulty breathing
Chest pain
Extreme fatigue
You may need antiviral medications like Tamiflu, which work best when taken early.
Should You Still Get the Flu Shot?
Absolutely. Even if the vaccine isn’t perfect, it’s your best defense against the flu. Benefits include:
Lower risk of severe illness
Fewer hospitalizations
Protection for vulnerable groups (elderly, pregnant women, children).
Final Thoughts
While the flu vaccine doesn’t make you completely immune, it greatly reduces your chances of getting seriously ill. Combine vaccination with healthy habits and visit your doctor for advice and what to do for the best protection.
Consult Top Specialists
Consult a top general practitioner for the best advice
Dr. Mainak Baksi
General Practitioner
13 Years • MBBS , MD (MPH)
Howrah
Mainak Baksi Clinic, Howrah
(50+ Patients)
Dr. M L Ezhilarasan
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6 Years • MBBS
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Apollo 24|7 Clinic - Andhra Pradesh, Visakhapatnam
Dr. Dhankecha Mayank
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Hyderabad
Apollo 24|7 Clinic - Telangana, Hyderabad
Dr. Rajib Ghose
General Physician/ Internal Medicine Specialist
25 Years • MBBS
East Midnapore
VIVEKANANDA SEBA SADAN, East Midnapore
Dr. J T Hema Pratima
General Practitioner
9 Years • MBBS
Chennai
Apollo 24|7 Clinic - Tamilnadu, Chennai
(325+ Patients)
Consult Top Specialists
Dr. Mainak Baksi
General Practitioner
13 Years • MBBS , MD (MPH)
Howrah
Mainak Baksi Clinic, Howrah
(50+ Patients)
Dr. M L Ezhilarasan
General Practitioner
6 Years • MBBS
Visakhapatnam
Apollo 24|7 Clinic - Andhra Pradesh, Visakhapatnam
Dr. Dhankecha Mayank
General Practitioner
6 Years • MBBS
Hyderabad
Apollo 24|7 Clinic - Telangana, Hyderabad
Dr. Rajib Ghose
General Physician/ Internal Medicine Specialist
25 Years • MBBS
East Midnapore
VIVEKANANDA SEBA SADAN, East Midnapore
Dr. J T Hema Pratima
General Practitioner
9 Years • MBBS
Chennai
Apollo 24|7 Clinic - Tamilnadu, Chennai
(325+ Patients)
