Chlorfenapyr-pyrethroid nets for pyrethroid-resistant malaria vectors: efficacy, resistance risks, and policy...

Area of Science:

• Medical Entomology
• Global Health
• Insecticide Resistance

Background:

• Widespread pyrethroid resistance in malaria vectors threatens global malaria control targets.
• The World Health Organization recommends chlorfenapyr-pyrethroid combination nets as a key intervention against resistant vectors.

Purpose of the Study:

• To systematically review the performance, resistance risks, and policy implications of chlorfenapyr-pyrethroid nets.
• To synthesize evidence on next-generation insecticide-treated nets for malaria vector control.

Main Methods:

• Systematic literature search (2010-2024) across major databases (PubMed, Embase, WHO IRIS, Google Scholar).
• Inclusion of 31 eligible studies from 113 records.
• Analysis of mosquito mortality, malaria incidence, and resistance patterns.

Main Results:

• Chlorfenapyr-pyrethroid nets show superior efficacy (1.8x increased mosquito mortality) against resistant Anopheles populations compared to pyrethroid-only nets.
• Community trials indicate 40-60% reductions in malaria infection incidence and entomological inoculation rates.
• Early signs of chlorfenapyr resistance detected in Anopheles gambiae, linked to CYP6P4 overexpression and agricultural pesticide use.

Conclusions:

• Chlorfenapyr-pyrethroid nets are a valuable short-term tool against pyrethroid resistance.
• Long-term effectiveness requires integrated resistance management, including rotational deployment, enhanced surveillance, and a One Health approach.
• Sustaining progress towards 2030 malaria targets depends on proactive resistance management strategies.