First record of Anopheles minimus C and significant decrease of An. minimus A in central Vietnam

Area of Science:

• Medical Entomology
• Molecular Biology
• Public Health

Background:

• Anopheles minimus s.l. is a primary malaria vector in Southeast Asia.
• Species A of Anopheles minimus s.l. was dominant in central Vietnam before 1998.
• Changes in vector species composition can significantly affect malaria transmission.

Purpose of the Study:

• To identify the specific status of Anopheles minimus s.l. collected in central Vietnam from 1993 to 2002.
• To monitor shifts in Anopheles minimus species composition over time.
• To investigate the impact of vector control measures on malaria vector populations.

Main Methods:

• Collection of Anopheles minimus s.l. samples from Khanh Phu commune, central Vietnam, between 1993 and 2002.
• Species identification using an allele-specific polymerase chain reaction (PCR) assay.
• Analysis of wing morphology to observe changes in Anopheles minimus s.l. populations.

Main Results:

• The study documented the first record of Anopheles minimus C in central Vietnam.
• A significant reduction in Anopheles minimus A was observed starting in 1998.
• The decline of Anopheles minimus A coincided with the widespread use of permethrin-treated bednets.

Conclusions:

• Selective vector control, such as permethrin-treated bednets, can alter malaria vector species composition.
• The geographic distribution of malaria vectors in Southeast Asia requires further investigation.
• Accurate species identification is crucial for understanding and managing malaria transmission dynamics.