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When Exactly Should You Get A Flu Shot And Is It Necessary If You Got It Last Year?

We’re nearing the end of September and getting closer to the flu season. Here’s what an expert has to say about when you should get your flu vaccine. 

Tenzin Chodon
Written by: Tenzin ChodonUpdated at: Sep 23, 2023 12:45 IST
When Exactly Should You Get A Flu Shot And Is It Necessary If You Got It Last Year?

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Vaccines are an effective way to reduce one's risk of developing diseases. It works along with your body's immune system to build protection against harmful viruses like influenza, also known as the flu. It is a highly contagious viral infection that spreads through the air, when people talk, cough, or sneeze or when people touch contaminated surfaces. 

While COVID-19 sparked tremendous fear among people, given its severity, greater hospitalisation rate and faster transmission risk, one forgets that the influenza virus has survived the tides of time and continues to pose risk to vulnerable groups of people, including older adults. In fact, the World Health Organization (WHO) notes that annual influenza epidemics are estimated to result in about 30-50 lakh cases of severe illness, and about 2.9-6.5 respiratory deaths. worldwide. 

Also Read: Flu Vaccination Campaign Delivers Promising Results in Reducing Severe Illness And Hospital Admissions, CDC

What Is Flu And How Does Flu Vaccine Help?

Flu is a respiratory infection that affects the nose, throat and lungs. It is caused by the Influenza virus, which comprise 4 types, namely types A, B, C and D.

According to the WHO, influenza A and B viruses are more prevalent and cause seasonal epidemics. Influenza A is divided into subtypes A(H1N1) and A(H3N2), which are currently circulating among humans. 

Common symptom of the flu include:

  • Fever
  • Dry cough
  • Headache
  • Muscle and joint pain
  • Severe malaise
  • Sore throat
  • A runny nose

The WHO says flu-associated cough can be severe and can last 2 or more weeks. 

Role Of Flu Vaccine

"The flu vaccine's primary purpose is to prevent influenza infection by stimulating your immune system to produce antibodies against specific flu virus strains," says Dr Hari Kishan, Senior General Physician, MBBS, MD, MRCP Kamineni Hospitals, L.B Nagar, Hyderabad. 

According to the WHO, influenza vaccines offer approximately 70-90% protection against clinical disease in healthy adults, provided there is a good match between the vaccine antigens and circulating virus(es). 

Dr Kishan adds, "While it may not offer complete protection, getting a flu shot is crucial. It can still reduce the severity of illness, lower the risk of severe complications, and contribute to overall community immunity, protecting those who can't be vaccinated."

The US Centers for Disease Control and Prevention (CDC) recommends everyone who is six months of age and older to get an influenza (flu) vaccine every season. However, the CDC says, “Different influenza vaccines are approved for different age groups. Some people (for example, pregnant people and people with some chronic health conditions) should not get some types of influenza vaccines, and some people should not receive flu vaccines at all (though this is rare).” 

Also Read: Protecting Two Lives: The Crucial Role Of Flu Vaccine In Pregnancy

When Is The Right Time To Get A Flu Shot?

According to Dr Kishan, the best time to receive a flu shot is in early fall, around September or October, before flu season hits its stride. 

“This gives your body time to build immunity,” he says. 

However, those of you who miss that window, it's never too late. 

“Flu can stick around into spring, so getting vaccinated any time before exposure is smart,” the doctor adds. 

Is It Necessary To Get A Flu Shot Every Year?

Dr Kishan strongly advises people to get a flu shot every year. 

He explains, “The reason for annual vaccination is twofold. First, the influenza virus is known for its ability to mutate and change over time. This means that new strains of the virus can emerge each year. To ensure that you are protected against the most recent and prevalent strains, it is crucial to update your flu vaccine annually. Second, the effectiveness of the flu vaccine may wane over time. Antibodies generated by the vaccine gradually decline, reducing your immunity. Annual vaccination helps boost and maintain your immunity levels, providing consistent protection against the flu.”

Other Ways To Prevent A Flu Infection

Besides getting vaccinated, here are some other ways to protect yourself against the virus:

  • Maintain good hand hygiene through regular hand-washing and using a hand sanitiser when needed
  • Avoid close contact with sick individuals
  • Practise respiratory etiquette, and disinfect frequently-touched surfaces
  • Wear masks in public
  • Prioritise a healthy lifestyle
  • Minimise face-touching
  • Stay informed about local flu activity 

A Final Word

Flu is an all-year long affair, which is why getting your flu shots is extremely important. Moreover, you must update your vaccination doses every year, as viruses mutate and immunity wanes over time. People at a greater risk of severe disease or complications should not only get vaccinated, but must also take necessary measures against contagious illnesses.