Risk-Group Surveillance
Even though Sri Lanka has successfully eliminated malaria, the risk of reintroduction remains due to international travel, labour migration, and regional vector presence.
To safeguard the nation’s malaria-free status, the Anti-Malaria Campaign (AMC) conducts risk-group surveillance — a proactive system to identify and monitor populations most vulnerable to malaria infection and potential transmission.
Who Are Considered Risk Groups?
Risk groups are individuals or communities who have a higher probability of exposure to malaria parasites or mosquito vectors. They include:
- Returnees from malaria-endemic countries (especially Africa, South and Southeast Asia).
- Foreign migrant workers and students arriving from endemic regions.
- Military personnel, peacekeepers, or contract workers returning from high-risk missions abroad.
- Pilgrims and travellers visiting countries with active malaria transmission.
- Residents of high-receptivity areas — locations where Anopheles mosquitoes still exist and can support malaria transmission.
- Populations living near ports, airports, and border entry points.
How Risk-Group Surveillance Works
Risk-group surveillance ensures early detection and treatment of imported malaria cases before they can spread locally.
The process involves multiple coordinated activities led by Regional Malaria Officers (RMOs), Public Health Laboratory Technicians (PHLTs), and field teams under AMC guidance.
1. Screening and Case Detection
- All returnees from endemic countries are screened for malaria parasites using microscopy or Rapid Diagnostic Tests (RDTs).
- Mobile malaria screening clinics are conducted at international airports, seaports, military camps, and community settings.
- Individuals with fever or malaria-like symptoms are tested immediately and re-tested after 3–4 weeks (secondary screening).
2. Mapping and Monitoring
- RMOs maintain updated databases of at-risk populations and areas, including work sites, hostels, and construction zones.
- GIS-based mapping helps identify clusters of high-risk individuals and prioritize surveillance coverage.
3. Continuous Follow-Up
- All identified risk-group members are followed up through home visits or contact tracing.
- Health education and preventive advice (including use of insecticide-treated nets) are provided.
- If a malaria-positive case is detected, case-based reactive response is initiated immediately in the area.
Why Risk-Group Surveillance Matters
- Prevents the re-establishment of local transmission in receptive areas.
- Ensures early diagnosis and complete treatment of imported infections.
- Protects communities living near high-risk zones such as ports of entry, development sites, and resettlement areas.
- Supports national and global efforts to sustain malaria elimination.
“Every traveller returning from a malaria-endemic country must be screened and, if needed, treated — because even one missed infection can restart transmission.”— Anti-Malaria Campaign, Ministry of Health