Leprosy Prophylaxis
Single-dose rifampicin (SDR) at 600 mg for adults (or 150-450 mg for children based on weight) is the recommended post-exposure prophylaxis for contacts of newly diagnosed leprosy patients, reducing the risk of developing leprosy by 50-60% over 2 years. 1, 2
Who Should Receive Prophylaxis
Contacts eligible for SDR prophylaxis include: 2, 3
- Household contacts of newly diagnosed leprosy patients
- Neighbors living within 100 meters of the index case
- Social contacts with regular exposure to the index patient
- Minimum age of 2 years (children under 2 are typically excluded) 4
Screening Before Prophylaxis
Before administering SDR, contacts must be screened to exclude: 2, 3
- Active leprosy disease (skin lesions with loss of sensation, thickened peripheral nerves, or other clinical signs)
- Active tuberculosis (cough, fever, weight loss, night sweats)
- Pregnancy (relative contraindication requiring risk-benefit assessment)
- Severe hepatic disease (rifampicin is hepatically metabolized)
- Known hypersensitivity to rifampicin
Approximately 13% of screened contacts are excluded from SDR, primarily due to health reasons, age restrictions, or detection of active disease. 2
Dosing Regimen
Standard SDR prophylaxis dosing: 1, 2, 4
- Adults and children ≥5 years: 600 mg rifampicin as a single dose
- Children 2-4 years: 150-300 mg rifampicin (weight-adjusted)
- Administration: Single dose, taken on empty stomach when possible
Emerging enhanced regimen (investigational): 4
- Bedaquiline plus rifampicin is being evaluated in the BE-PEOPLE trial for potentially greater effectiveness
- Household contacts receive a second dose at 4 weeks in this protocol
- This remains investigational and is not yet standard of care
Implementation Strategy
The "drives" approach is most effective for contact tracing: 1
- A trained team systematically contacts all eligible index cases in a district
- Contacts are traced, screened, and SDR administered during organized campaigns
- This approach achieved 72-97% contact screening rates across multiple countries 1, 2
Key feasibility data from the LPEP programme: 2
- 174,782 of 179,769 contacts (97.2%) were successfully traced and screened
- 151,928 contacts (86.9% of those screened) received SDR
- Only 0.7% of eligible contacts refused prophylaxis
- No serious adverse events were reported
Safety and Tuberculosis Resistance Concerns
SDR poses negligible risk of inducing rifampicin resistance in M. tuberculosis: 5
- Single-dose exposure is insufficient to select for resistant M. tuberculosis strains
- The benefits of reducing leprosy transmission far outweigh theoretical TB resistance risks
- Screening for active TB before SDR administration is the critical safeguard
Common pitfall to avoid: Do not withhold SDR from contacts due to unfounded concerns about TB resistance. The expert consensus is clear that the risk is negligible when active TB is excluded. 5
Monitoring and Follow-up
Post-prophylaxis surveillance should include: 1, 3
- Annual screening of contacts for at least 2-3 years after SDR administration
- Active case detection in the community surrounding index cases
- Documentation of any new leprosy cases among contacts (expected rate: approximately 46 per 10,000 screened contacts) 2
Treatment vs. Prophylaxis Distinction
Do not confuse prophylaxis with treatment of active disease: 6, 7
- Prophylaxis: Single-dose rifampicin 600 mg for asymptomatic contacts
- Treatment of active leprosy: Multidrug therapy (MDT) with dapsone 100 mg daily plus rifampicin 600 mg monthly for 6-24 months, often with clofazimine 50-100 mg daily for multibacillary disease 6, 7
Critical distinction: Patients with confirmed leprosy require full MDT regimens, not SDR prophylaxis. Administering only SDR to someone with active disease risks treatment failure and secondary dapsone resistance. 7
Program Integration
SDR prophylaxis integrates effectively into existing leprosy control programs: 2, 3