Screening of mosquitoes for filarioid helminths in urban areas in south western Poland—common patterns in European Setaria tundra xenomonitoring studies

Abstract

In recent years, numerous studies screening mosquitoes for filarioid helminths (xenomonitoring) have been performed in Europe. The entomological monitoring of filarial nematode infections in mosquitoes by molecular xenomonitoring might serve as the measure of the rate at which humans and animals expose mosquitoes to microfilariae and the rate at which animals and humans are exposed to the bites of the infected mosquitoes. We hypothesized that combining the data obtained from molecular xenomonitoring and phenological studies of mosquitoes in the urban environment would provide insights into the transmission risk of filarial diseases. In our search for Dirofilaria spp.-infected mosquitoes, we have found Setaria tundra-infected ones instead, as in many other European studies. We have observed that cross-reactivity in PCR assays for Dirofilaria repens, Dirofilaria immitis, and S. tundra COI gene detection was the rule rather than the exception. S. tundra infections were mainly found in Aedes mosquitoes. The differences in the diurnal rhythm of Aedes and Culex mosquitoes did not seem a likely explanation for the lack of S. tundra infections in Culex mosquitoes. The similarity of S. tundra COI gene sequences found in Aedes vexans and Aedes caspius mosquitoes and in roe deer in many European studies, supported by data on Ae. vexans biology, suggested host preference as the most likely cause of the mosquito genus-biased infections. High diversity of the COI gene sequences isolated in the city of Wroclaw in south western Poland and the presence of identical or almost identical sequences in mosquitoes and roe deer across Europe suggests that S. tundra has been established in most of Europe for a very long time.

Dirofilaria sp. and Blood Meal Analysis in Mosquitoes Collected in Vojvodina and Mačva, and the First Report of Setaria tundra (Issaitshikoff & Rajewskaya, 1928) in Serbia

“…sticticus, Aedes rossicus Dolbeskin & Gorickaja 1930, and Cq. richiardii, in the following countries: Poland [95,96], Hungary [27,97], and Germany [22,26].…”

Mosquitoes (Diptera: Culicidae) of Poland: An Update of Species Diversity and Current Challenges

“…The knowledge of the distribution of Culicidae in Poland still remains fragmentary because regular monitoring of the presence of mosquito species is limited to only a few areas. Additionally, some data on mosquito species occurrence are included in papers concerning biocontrol [6][7][8], evening activity of synanthropic species [9], factors influencing the distribution of floodwater mosquito eggs [8], and the detection of pathogens [10][11][12][13].…”

Influence of mosquito-borne biological agents on health risks among soldiers and military personnel

“…It is worth mentioning that polymorphisms of DNA sequences within primer binding sites used in D. repens detection methods in European studies were identified, and non-specific amplification of DNA of another nematode, Setaria tundra, also occurred. The authors highlighted the need to develop a standardised test kit for sensitive and specific detection of D. repens [37,38].…”