Dr Bharat Purandare explains the importance of yearly vaccinations.
Influenza caused by the influenza virus (an orthomyxovirus) is extremely contagious. The virus spreads in the air through droplets when an infected person coughs or sneezes. Influenza affects the respiratory system. Touching infected surfaces and then touching the nose or mouth could also spread the infection.
Influenza can range from simple self-limiting illness to a serious illness leading to hospitalisation and sometimes even death if left untreated. Flu (as influenza is called in common language) affects the bronchial tubes and lungs, causing inflammation that can then lead to bacterial pneumonia. Symptoms of flu include:
- Dry cough
- Runny nose
- Sore throat
- Muscle ache
In serious illness symptoms seen are breathlessness, chest pain, blood phlegm production and drowsiness.
Importance of vaccinations
Vaccination is a simple and effective clinical tool to prevent illness. More than 14 infectious diseases can be prevented by effective vaccination. So, vaccination is important in adults too.
Flu vaccines are given in the arm (muscle) with a needle. They are advised yearly. They help the body develop antibodies about two weeks after vaccination. These antibodies protect the body against future infections.
Types of flu vaccine
Traditional flu vaccines are called trivalent vaccines as they protect against three viruses – influenza A (H1N1) virus, influenza A (H3N2) virus and influenza B virus. Flu vaccines called quadrivalent vaccines help protect against these three viruses and also another type of B virus.
Standard-dose trivalent shots are manufactured using virus grown in eggs.
The trivalent vaccine includes a formulation that is given according to age group with:
- a high-dose trivalent shot is approved for people 65 and older.
- a recombinant trivalent shot that is egg-free is approved for people between the ages of 18 and 64 years, including pregnant women.
Quadrivalent flu vaccines include formulations also based on age groups. They are:
- A quadrivalent flu shot containing virus grown in cell culture. This is approved for children from 4 to 18 years of age.
- A recombinant quadrivalent flu shot is approved for people 18 years of age and older, including pregnant women.
There is also an intradermal quadrivalent flu shot which is injected into the skin. This requires a smaller needle. It is given to people 18 years and older.
Diabetes and flu vaccine
The immunity produced by one dose of the flu vaccine is short-lasting. Also, the flu virus changes and evolves every year. Therefore, people who are having Diabetes are advised to take flu vaccination every year. It is important for adults who have Diabetes to be vaccinated as well. Immunity is a major concern for people with Diabetes. Due to hampered defence mechanism, people with Diabetes are at a high risk of contracting various infections like pneumonia (infection in lungs), bacteraemia (infection in the blood) and meningitis (infection in the lining of spinal cord and brain). Doctors prescribe vaccinations to people with Diabetes to protect against influenza (flu), pneumonia and hepatitis B.
Amongst other infectious diseases, the most common and dangerous complication of influenza is pneumonia. Carried by a set of bacteria (pneumococcal bacteria), the disease affects the lungs and makes breathing difficult for people with Diabetes. It can lead to serious complications in people with Diabetes, even when their blood sugar levels are under control. People who are 65 years or older are recommended taking vaccination against invasive pneumococcal disease.
The annual flu vaccine is advised for all people but especially:
- Children, especially from 6 months to 5 years old
- Pregnant women
- Adults of age 65 and older People with health conditions like Diabetes and kidney disease
- Obese people with a body mass index (BMI) of 40 or more
- People travelling and living abroad
People who should not get the flu vaccine include children under 6 months old and people who are allergic to the vaccine or any of its ingredients. Minor side effects of flu vaccine in adults include:
- Itching, pain and swelling at the injection
- Muscle pain
Minor side effects of flu vaccine in children include:
- Abnormal crying
- Appetite loss
Severe side effects include high fever, weakness, dizziness, racing heart, trouble breathing and swelling around the lips or eyes. These are rare but it is important to seek medical attention in case any of these symptoms manifest.
The flu vaccine is recommended for all people including those with Diabetes. People with Type 1 or Type 2 Diabetes are at an increased risk of developing pneumonia because of the flu which is also preventable by another vaccine.
Therefore periodic vaccination should be a part of a Diabetes management plan. Ensure that you discuss with your doctor which vaccines are recommended for you.
Dr Bharat D. Purandare (M.D. Medicine, Fellowship in ID) is an Infectious Disease Physician.