Surveillance over invasion rate of blood-sucking mosquitoes with Dirofilaria spp. in the central part of the Khabarovsk krai

Objective: to evaluate necessity of surveillance over invasion rate of blood sucking mosquitoes with Dirofilaria spp. in central part of the Khabarovsk krai.

Materials and methods: a total number of 2979 female species of Culex, Anopheles, Aedes mosquitoes were captured during June, July and August in the Dada village of the Nanaysky district of the Khabarovsk krai. Captured mosquitoes were tested for presence of Dirofilaria immitis and Dirofilaria repens DNA with two methods: real-time polymerase chain reaction and polymerase chain reaction with amplification of products using species-specific primers and detection of the products in gel electrophoresis.

Results: Evaluation of dirofilaria life cycle revealed that in May there is not enough heat for development of the invasive stage of dirofilaria, 3 cycles of invasion are possible in June, 7 cycles - in July, and 5 cycles – in August.

Dirofilaria DNA was identified during all summer months. Should be noted that there was no statistically significant difference between mosquitoes invasion rate with Dirofilaria immitis (2.5 %) и Dirofilaria repens (2.1 %).

Conclusion: Circulation of dirofilariosis pathogens is possible not only in south part but also in central part of the Khabarovsk krai due to favorable climate conditions for development of microfilaria life cycle in bloodsucking mosquitoes during summer period. The results indicate a necessity of surveillance over invasion rate of blood-sucking mosquitoes with Dirofilaria spp in the observed territory.

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