Adverse events following immunization (AEFI) after yellow fever Vaccination.
- Mild Side Effects of Vaccination:-
- Yellow fever vaccine has been associated with fever and with aches, soreness, redness or swelling where the vaccine is given.
- These problems occur in up to 1 person out of 4.
- They usually begin soon after the vaccination, and can last up to a week.
- Most people will get a slight sore arm 2-10% may feel tired, headache, muscle aches, fever for 24 hours starting 3-9 days after the vaccine, of these 1% need to curtail regular activities
- More Serious Side Effects of Vaccination :-
- The risk of a vaccine causing serious harm, or death, is extremely low.
- Severe allergic reaction to a vaccine component (about 1 person in 58,000).
- Severe nervous system reaction (about 1 person in 125,000).
- Life-threatening severe illness with organ failure (about 1 person in 250,000).
- More than half the people who suffer this side effect die.
- These last two problems have never been reported after a booster dose.
- 1 in 130,000 will get immediate hypersensitivity – rash, itching faint or asthma – this is why you need to wait 60 minutes in the clinic
- 0.09-2.5 per million will get inflammation of multiple organs e.g. lungs, kidney, liver, spleen, skin, blood stream
- 1 in 8 million will get encephalitis (Inflammation of the brain)
3. What if there is a severe reaction?
a. What should I look for?
Look for any unusual condition, such as a high fever, behavior changes, or flu-like symptoms
Signs of an allergic reaction can include difficulty in breathing, hoarseness or wheezing, hives, paleness, weakness, a fast heart-beat, or dizziness within a few minutes to a few hours after the vaccination.
b. What should I do?
Call a doctor, or get the person to a doctor right away. Tell the doctor what happened, the date and time it happened, and when the vaccination was given.
There have been rare reports of serious side-effects from the yellow fever vaccine. The rates for these severe ‘adverse events following immunization’ (AEFI), when the vaccine provokes an attack on the liver, the kidneys or on the nervous system, leading to hospitalization, are between 0.4 and 0.8 per 100 000 people vaccinated.
The risk is higher for people over 60 years of age and anyone with severe immunodeficiency due to symptomatic HIV/AIDS or other causes, or who have a thymus disorder. People over 60 years of age should be given the vaccine after a careful risk-benefit assessment.
People who are usually excluded from vaccination include:
- infants aged less than 9 months, except during an epidemic when infants aged 6-9 months, in areas where the risk of infection is high, should also receive the vaccine;
- pregnant women – except during a yellow fever outbreak when the risk of infection is high;
- people with severe allergies to egg protein; allergic to any eatable fruit and
- People with severe immunodeficiency due to symptomatic HIV/AIDS or other causes like drugs used in treatment of cancers, or who have a thymus disorder.
In accordance with the International Health Regulations (IHR), countries have the right to require travelers to provide a certificate of yellow fever vaccination. If there are medical grounds for not getting vaccinated, this must be certified by the appropriate authorities.
IHR are a legally binding framework to stop the spread of infectious diseases and other health threats. Requiring the certificate of vaccination from travelers is at the discretion of each State Party, and it is not currently required by all countries.
