Because the virus strains that circulate in the community change in most years, so a new vaccine has to be made.
The effectiveness of the vaccine begins to decline after 6-8 months.
Yes. The World Health Organization estimates between 250,000 – 500,000 die from influenza related causes every year.
In adults, the symptoms of influenza can include:
- Fever
- Dry cough
- Muscle and joint pain
- Tiredness/extreme exhaustion
- Headache
- Sore throat
In children, influenza may present as:
- High fever
- Listlessness or lack of energy
- Cough
- Children can also get diarrhoea and vomiting with influenza infection.
Duration of symptoms – typically 1-2 weeks for influenza, a few days for a cold.
Influenza often produces a high fever, with muscular aches and shivering.
It may take several weeks to fully recover from influenza, even for healthy younger people, and for some people the infection may lead to serious consequences including hospitalisation and death.
No. The vaccine contains only inactivated viral particles (a virus killed and broken apart) and therefore is incapable of causing influenza infection. People who develop a runny nose or sore throat may have been exposed to another virus before they received the influenza vaccine.
The most common side effects are pain or tenderness around the injection site.
Some people may experience fever, headache or irritability. These symptoms are mild and usually clear up within a few days.
Vaccination is contraindicated in case of severe egg allergy, including anaphylactic reaction.1
1. World Health Organization (WHO)
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