Vaccines save lives — millions every year — but like any medical intervention, they’re not completely free from side effects. The key for every future doctor is knowing what’s normal, what’s not, and what to do when reactions occur.
🧠 What Is an AEFI?
Understanding AEFI
An Adverse Event Following Immunization (AEFI) is any untoward medical occurrence which happens after vaccination and does not necessarily have a causal relationship with the vaccine. In other words: It happens after the shot — but not always because of the shot.
⚙️ Classification of AEFIs
| Type | Description | Example |
|---|---|---|
| Vaccine reaction | Caused by the vaccine itself | Fever after DPT, pain at injection site |
| Program error | Due to mistakes in handling or administration | Abscess from unsterile injection |
| Injection reaction | Due to anxiety or pain, not the vaccine | Fainting after injection |
| Coincidental event | Happens by chance, unrelated to vaccine | Fever from malaria after vaccination |
| Unknown | Cause can’t be determined | Rare unexplained cases |
💡 Mnemonic: “V-P-I-C-U” — Vaccine, Program, Injection, Coincidental, Unknown.
🔹 Common Minor Reactions
Expected and Self-Limiting
These are expected and self-limiting:
- Local: Pain, redness, mild swelling.
- Systemic: Mild fever, irritability, fatigue, loss of appetite.
🩺 Management: Reassure, give paracetamol if fever >38.5°C, and encourage fluids.
🚨 Serious or Rare Reactions
Require Prompt Action
These are uncommon but require prompt action:
- Severe allergic reactions (anaphylaxis)
- Seizures (from high fever post-DPT or MMR)
- Toxic shock (from contamination)
- Encephalopathy (extremely rare, mostly coincidental)
🆘 Management: Give adrenaline (0.01 mg/kg IM) for anaphylaxis immediately. Maintain airway and circulation. Report the event through the AEFI surveillance system.
🧾 AEFI Surveillance and Reporting
Reporting Process
Every health worker must:
📊 Data from these reports help detect problem batches or training gaps — and maintain public trust.
💬 Counseling Parents
Empathetic Guidance
Be calm, factual, and empathetic: “Mild fever and pain are normal — it shows the immune system is working. But if your child has difficulty breathing, persistent vomiting, or becomes unusually sleepy, please return immediately.” Reassurance builds vaccine confidence, not fear.
🧠 Quick Recap
| Key Point | Summary |
|---|---|
| AEFI = | Any unwanted event after vaccination |
| Mnemonic | V-P-I-C-U (Vaccine, Program, Injection, Coincidental, Unknown) |
| Common reaction | Fever, soreness, mild swelling |
| Serious reaction | Anaphylaxis — treat with IM adrenaline |
| Importance | Early reporting keeps vaccination safe |
💡 In a Nutshell
AEFIs don’t mean vaccines are unsafe — they mean health systems are alert and responsible. Recognize, manage, and report — because maintaining trust in vaccines saves more lives than any single dose.