AEFI (ADVERSE EVENT FOLOWING IMMUNIZATION) is any untoward medical occurrence which follows immunization & which doesn’t necessarily have a casual relationship with the usage of vaccine.
ADVERSE EVENTS ARE-
- REACTIONS INHERENT TO INCULATION- Local pain, swelling, nodules, redness, sterile abscess, tenderness [BCG- pain, swelling, redness]. General- Fever, malaise, headache.
- REACTIONS DUE TO FAULTY TECHNIQUE.
- REACTIONS DUE TO HYPERSENSITIVITY- Immediate- Anaphylactic shock. Delayed- Pyrexia, Arthralgia, Myalgia, Urticaria, oedema.
- NEUROLOGICAL INVOLVEMENT- Post vaccination encephalitis (BPL anti rabies vaccine). Guillain- Barre Syndrome (Swine Influenza vaccine). Sub-acute sclerosing pan encephalitis (Measles vaccine).
- PROVOCATIVE REACTIONS- Provocative polio (APT or PTAP against Diptheria).
- OTHERS- Damage to foetus (Rubella to pregnant woman). So, AEFI include events beyond side effects of vaccines.