Laboratory An. gambiae s.l. mosquito colonies show sustained high transmission of Microsporidia sp. MB and a small...

Area of Science:

• Entomology
• Microbiology
• Genetics

Background:

• Microsporidia sp. MB is a natural symbiont of Anopheles mosquitoes.
• MB can inhibit Plasmodium parasite development and transmission.
• MB-based malaria control strategies require stable mosquito colonies with high MB prevalence.

Purpose of the Study:

• To establish stable Anopheles mosquito colonies carrying Microsporidia MB at high frequency.
• To investigate the prevalence and density of MB in different mosquito life stages and tissues.
• To assess the impact of MB on mosquito egg production and spore presence in eggs.

Main Methods:

• Established Anopheles colonies (An. coluzzii and An. gambiae s.l.) from field-caught mosquitoes.
• Utilized a duplex qPCR assay to quantify MB density in various life stages and tissues.
• Monitored egg production and examined eggs for MB spores.

Main Results:

• Successfully established stable Anopheles colonies with high MB prevalence and density for over two years.
• MB prevalence and density were highest in eggs and adult females, and lowest in larvae.
• MB density increased in ovaries after blood feeding, suggesting sporogony activation.
• MB spore production correlated with increased non-hatching white eggs and a slight reduction in overall egg count.

Conclusions:

• Stable Anopheles colonies carrying MB can be established and maintained.
• Understanding MB's impact on egg production is crucial for its application as a malaria control tool.
• These findings represent significant progress towards developing MB as a novel malaria control strategy.