Mosquito vectors of lymphatic and zoonotic filariasis in Malaysia: a systematic review and proportionate meta-analysis of infection rates.

Lymphatic and zoonotic filariasis in Malaysia are transmitted by multiple mosquito species, but the infection rates in these vectors have not been quantitatively reviewed. This systematic review and meta-analysis of proportions compiled species-level infection data for Malaysian mosquitoes infected with Brugia malayi, Brugia pahangi, Wuchereria bancrofti and Dirofilaria immitis. Searches of PubMed, Scopus and Web of Science identified 297 records; 12 studies met the predefined inclusion criteria, yielding 42 mosquito-parasite records involving Mansonia, Anopheles, Armigeres, Aedes and Culex. Infection rates were pooled separately for natural and experimental infections using generalised linear mixed-effects models with logit transformation. For B. malayi, natural infection rates in Mansonia and Anopheles were very low (pooled 0.35%; 0.02-4.46% across species) despite large sample size, whereas experimental infections were far higher (pooled 72.4%). Wuchereria bancrofti showed low natural infection rates (pooled 2.1%; 0.9-6.7% across species) and higher experimental infection (pooled 36.8%). In contrast, B. pahangi showed high natural infection in Armigeres subalbatus (pooled 7.2%; range 3.9-14.4%), with experimental infection of 45.0%. Dirofilaria immitis showed very low natural infection (pooled 0.06%) but comparatively high experimental infection (pooled 29.1%), reaching 55-69% in Aedes togoi. Natural and experimental infection rates differed significantly for every parasite (tests for subgroup differences, p < 0.0001). Overall, classical human filariasis parasites now circulate at low levels in their traditional Mansonia and Anopheles vectors, while zoonotic parasites are maintained in peri-domestic mosquito-animal cycles. These findings highlight the need for integrated One Health strategies combining mass drug administration, peri-domestic vector control, improved diagnostics and veterinary interventions to achieve sustainable filariasis elimination in Malaysia.