Prevalence of human and non-human primate parasites in anopheline mosquitoes: a cross-sectional epidemiological study in Southern Vietnam.

BACKGROUND

Human malaria is a major threat in rural communities of central Vietnam. and species are critical malaria vectors in Vietnam, which transmit parasites. However, the entomological aspects of malaria transmission in some of the central provinces of Vietnam remain unexplored. Hence, a cross-sectional entomological survey was carried out to identify the malaria vector species and the transmission of parasites in seven endemic provinces of Vietnam.

METHODS

Mosquitoes were collected from seven provinces, Gia Lai, Khanh Hoa, Phu Yen, Ninh Thuan, Binh Thuan, Dong Nai, and Binh Phuoc. The collection was conducted for four to eight consecutive nights using three established methods, indoor and outdoor human landing catches and light trap method. Nested-PCR analysis was performed to detect the species in the separated thorax and the abdomen of the individual mosquitoes.

RESULTS

A total of 2278 mosquitoes belonging to one of the four species of anopheline mosquitoes, , , , and were collected. Among the collected mosquitoes, 1398 were analysed using nested-PCR, of which, 40 mosquitoes were positive for parasites. Most of these parasites were detected in the samples from the thorax region, followed by the abdominal portion. The parasites were detected in both the thorax and abdomen of . Seven species of parasites were detected during the analysis, of which, was the most common species, followed by , , , , , and . Out of the 49 positive samples, 12 showed mixed infections. Co-infection of with human and other non-human primate species was common.

CONCLUSIONS

This study demonstrated the presence of human and non-human primate infection in , a predominant malarial vector. Further, we showed that and species also take part in malarial transmission. This might potentially lead to an alarming situation conducive for the emergence of novel zoonotic malaria.