Influenza commonly known as flu can lead to hospitalization and even death. It can affect anyone even healthy person. Every flu season it differs and can affect people differently. Severe complications include pneumonia, sinusitis, ear infection, bronchitis, meningitis and even death. People prone to more serious complications include the very young (less than 5 years old), immuno-compromised patients, chronic lung/heart disease patients, diabetic patients , renal failure patients on dialysis , those on long term aspirin who are at risk of reye syndrome and those with thalassemia.
Influenza is highly contagious and can spread from person to person via respiratory droplets, sharing of food with someone down with flu and also contact with surfaces contaminated with the virus and subsequently touching one's own nose/mouth. Prevention by influenza vaccination via a flu shot or a flu nasal spray is recommended.
Symptoms of influenza include high fever, chills, headache, sore throat, cough, weakness, muscle ache, sneezing, stuffy nose, nasal discharge and tiredness.
High fever of 38-41 degree Celsius, extreme exhaustion and severe headaches are more common in influenza cases rather than common cold.
The influenza vaccine should be taken two weeks before travel as it takes up to 2 weeks for the antibodies to be developed in the body. The antibodies will provide protection against infection caused by the virus in the vaccine. As the flu virus evolve all the time and immunity decrease with time hence annual vaccination is recommended.
The trivalent vaccine protects against two influenza A viruses (H1N1 and H3N2) and a influenza B virus. Currently H7N9 the bird flu virus is not covered in the vaccine.
The quadrivalent flu vaccine protects against two influenza A viruses and two influenza B viruses. It is available in the form of injection vaccine and a nasal spray vaccine. The nasal spray vaccine can be given to those age 2-49 years old but recommended age group is still 2-8 years old.
Everyone 6 months and older should get influenza vaccination especially those who are at risk of getting complications. It should ideally be taken during the flu season.
Possible side effects of the vaccine
Some possible side effects post vaccination include:
- muscle ache and headache
- runny nose
- sore throat
- redness and swelling at injection site
These minor side effects can occur after vaccination and may last 1-2 days. Rarely anaphylactic allergy reaction occurs.
Contraindication to the influenza injection
1. Children younger than 6 months old
2. People who has allergy reaction to the content of vaccine like egg, gelatin, antibiotics and other ingredients.
3. History of Guillain-Barré Syndrome
4. Acutely ill at time of vaccine, to take after recovey.
Contraindication to Nasal spray vaccine
1. Children younger than 2 years old and adults older than 50 years old
2. People allergy to eggs and allergy to contents of nasal spray vaccine.
3. Pregnant women
5. Children on long term aspirin may have increased risk of reye's syndrome
6. History of asthma as the nasal spray may trigger an attack.
7. Those who had anti-viral medications within 48 hours of vaccination.
8. History of Guillain-Barré Syndrome
9. Acutely ill at time of vaccine, to take after recovery.