Post Exposure prophylaxis may reduce the likelihood of HIV infection after high-risk exposure. PEP may either prevent the establishment of infection or prevent new infection while allowing clearance of already infected cells. PEP is particularly effective within 24 to 48 hours of exposure.
1. All infection prevention programmes should be in place and health workers should follow procedures at all times to prevent exposure. In the event of possible exposure to HIV the following actions should be taken immediately.
2. All health workers accessing the post exposure prophylaxis package should receive counselling from a trained counsellor throughout the period and thereafter if necessary.
3. Treatment of exposure site: The wound site should be cleaned with soap and water/or in the case of mucous membranes flushed with water.
4. Timing of post-HIV exposure prophylaxis initiation
If therapy is necessary it should be initiated promptly, preferably 1 to 2 hours post exposure.
5. Assessment of exposure risk
Low risk exposure is
• Exposure to a small volume of blood or blood contaminated fluids from asymptomatics HIV-positive patients with low viral load
• An injury with a solid needle
• Any superficial injury or mucocutaneous exposure
High-risk exposure is:
• Exposure to a large volume of blood or potentially infectious fluids
• Exposure to blood or blood contaminated fluids from a patient with a high viral titre. i.e. in the AIDS phase or early sercoconversion phase of HIV
• Injury with a hollow bore needle
• Deep and extensive injury
• Drug resistance in source patient
6. Post -HIV exposure prophylaxis
Low risk:
Lamivudine 150 mg 12 hourly x 28 days
Zidovudine 200 mg 8 hourly x 28 days
High risk:
Zidovudine 200 mg 8-hourly x 28 days
Lamivudine 150 mg 12 hourly x 28 days
Indinavir 800 mg 8 hourly x 28 days
Nelfinavir 750 mg tid or 1250 mg bid x 28 days
7. Recommended drug toxicity and HIV serology testing after exposure
Baseline tests:
Full blood count
Liver and renal function tests, Hepatitis Surface Antigen
HIV serology/(PCR if available)
Two weeks:
Full blood count
Liver and renal function tests
Six weeks:
HIV serology
Three months:
HIV serology
Six months:
HIV serology
