Rabies Post-Exposure Prophylaxis (PEP) — A UK Guide for Animal Bites in PLAB 2

Ann Augustin
Jun 6
2 min read

Updated: Jun 26

Animal bites are common presentations in general practice and emergency care settings. While many are minor, some carry the life-threatening risk of rabies — a viral encephalitis with a high fatality rate once symptoms begin. Therefore, Post-Exposure Prophylaxis (PEP) is critical in preventing rabies after a potential exposure.

🐾 When to Suspect Rabies Risk

Rabies is not endemic in the UK, but exposures abroad or through imported animals warrant urgent assessment. The risk varies by:

Geography: Endemic areas include India, Southeast Asia, Africa, South America, and Turkey
Animal type: Dogs, cats, bats, monkeys, raccoons, foxes
Exposure type: Bite, scratch, or saliva contact with mucosa/open wound

🚨 Step 1: Assess the Exposure

Use the WHO classification to guide management:

Category	Exposure Description	PEP Action
I	Touching/feeding animals, contact with intact skin	No PEP
II	Nibbling uncovered skin, minor scratches (no bleeding)	Vaccine only
III	Bites/scratches with bleeding, saliva in wound/mucosa	Vaccine + HRIG

💉 Step 2: Rabies Vaccine Regimen (UK Schedule)

✅ For Previously Unvaccinated Individuals:

4-dose IM schedule: Day 0, 3, 7, and 21 (or 28)
+ HRIG on Day 0 for Category III exposures

Inject HRIG around the wound site as much as possible. Any remaining amount should be given IM at a distant site (not mixed with vaccine).

🧾 What If Vaccination History Is Unknown or Uncertain?

Treat the person as unvaccinated and give:

Full 4-dose vaccine regimen
HRIG if Category III exposure
Tetanus prophylaxis if indicated

Even if the patient recalls "some vaccine years ago" but is unsure of completion, do not risk it — follow the full PEP protocol.

♻️ For Previously Fully Vaccinated Individuals:

If the patient completed a full pre-exposure or post-exposure rabies vaccine course at any point in the past, and is immunocompetent:

Give 2 doses only: Day 0 and Day 3
No HRIG needed

✅ No boosters required if vaccinated and immunocompetent — protection is considered long-lasting.

⚠️ Special Cases

🧬 Immunocompromised Patients

Should always receive the full 5-dose PEP: Day 0, 3, 7, 14, and 28
HRIG is required, even if previously vaccinated

💉 Tetanus Consideration

All bite wounds (especially dirty or deep) must be assessed for tetanus risk:

Give a tetanus-containing vaccine (Td/IPV) if incomplete or unknown history
Add Tetanus Immunoglobulin (TIG) if high-risk wound and vaccine history is inadequate

🧠 Key Takeaway Summary

Patient Type	Vaccine Schedule	HRIG	Tetanus Consideration
Unvaccinated	4 doses (Day 0, 3, 7, 21/28)	Yes if Cat III	If not up to date
Unknown status	Same as unvaccinated	Yes if Cat III	If not up to date
Fully vaccinated	2 doses (Day 0, 3)	No	If not up to date
Immunocompromised	5 doses (Day 0, 3, 7, 14, 28)	Yes	As per risk

🧾 Final Notes

Always clean wounds immediately with soap and water
Do not delay PEP — it can save a life
Educate travellers to endemic areas about pre-exposure vaccination

📚 References: