Influenza (“flu”) is a contagious disease that is seen in different times of year in different countries. In India, there are 2 flu seasons- One is Post monsoons in July- August and other Flu season is in Peak winters in month of January.
Flu is caused by influenza viruses, and is spread mainly by coughing, sneezing, and close contact. These viruses as named as H1N1 (swine flu), H1N3, H1N2, etc.
Anyone can get Influenza. Flu strikes suddenly and can last several days. Symptoms vary by age, but can include:
- Runny or stuffy nose
- Sore throat & cough
- Muscle aches & fatigue
- Headache & body aches
- Loose stools
Flu can also lead to pneumonia and blood infections, and cause diarrhoea in children.
Flu is more dangerous for some people if they have other medical issues like heart problems, etc. Infants and young children, people 65 years of age and older, pregnant women and people with certain health conditions or a weakened immune system are at greatest risk.
In India, Influenza vaccine is recommended by Indian Academy of Pediatrics (IAP)for all High risk groups which include .
- Infants and young children from ages 6 month till age 5 years
- People 65 years of age and older
- Pregnant women
- People with certain health conditions or a weakened immune system
Like all other vaccines, a Flu vaccines prevents complications of Influenza like Pneumonias, Meningitis, etc and makes course of disease milder but it will not all together prevent a child from getting a flu. Also, it should be noted that vaccine includes only few of the viruses which are known to cause more severe disease. It doesn’t protect from many other routine seasonal viruses which cause common colds or coughs.
Types of vaccines
Various types of Influenza vaccines are available in India. Depending upon the number of virus types included it can be trivalent Vaccine (3 types) or Quadrivalent Vaccine (4 types). And Depending upon the technique used to prepare vaccine, it can be Live attenuated type or Inactivated/ Split Virion Type or a Sub-unit vaccine. Usually availability in Indian market varies every season and its desirable to use the Quadrivalent type with current seasons viruses included in vaccine as this vaccine is a seasonal vaccine and every year a different batch of vaccine is released around the flu season.
Initially 2 doses are administered with a minimum interval of 4 weeks, followed by an yearly dose, preferably before flu season.