Adult blackfly (Simulium damnosum s.l.) collection methods: overview and research needs

Area of Science:

• Medical Entomology
• Tropical Public Health
• Vector-Borne Disease Control

Background:

• River blindness (onchocerciasis) control relies on effective vector surveillance.
• Human Landing Catch (HLC) is the gold standard but has ethical and operational drawbacks.
• Evaluating alternative blackfly collection methods is crucial for programmatic success.

Purpose of the Study:

• To review and evaluate alternative blackfly collection methods.
• To assess methods against a Target Product Profile (TPP) for field use.
• To identify promising alternatives to Human Landing Catch (HLC).

Main Methods:

• Systematic literature review following PRISMA-ScR guidelines.
• Searched major databases for blackfly traps and onchocerciasis collection studies.
• Thematic synthesis of data, assessing performance against TPP criteria.

Main Results:

• Fifteen studies were included in the review.
• Esperanza Window Trap (EWT) and Host Decoy Trap (HDT) showed high catches in some settings.
• Modified HLC reduced exposure but still required human presence.

Conclusions:

• No single alternative method consistently outperformed HLC across all environments.
• Optimized EWT and HDT designs offer potential for ethical and effective onchocerciasis surveillance.
• Further development of traps is needed for widespread programmatic use.