Molecular detection of Wolbachia pipientis in natural populations of mosquito vectors of Dirofilaria immitis from continental Portugal: first detection in Culex theileri.
Wolbachia pipientis (Rickettsiales: Rickettsiaceae) protects mosquitoes from infections with arboviruses and parasites. However, the effect of its co-infection on vector competence for Dirofilaria immitis (Spirurida: Onchocercidae) in the wild has not been investigated. This study aimed to screen vectors of D. immitis for wPip, to characterize these, and to investigate a possible association between the occurrence of W. pipientis and that of the nematode. The presence of W. pipientis was assessed in the five mosquito potential vectors of D. immitis in Portugal. Polymerase chain reaction (PCR) products were sequenced, and wPip haplotypes were determined by PCR-restricted fragment length polymorphism (RFLP). Results showed that wPip was detected in 61.5% of Culex pipiens (Diptera: Culicidae) pools and 6.3% of Culex theileri pools. wPip 16s rRNA sequences found in Cx. theileri exactly match those from Cx. pipiens, confirming a mosquito origin, rather than a nematode origin, as some specimens were infected with D. immitis. Only wPip haplotype I was found. No association was found between the presence of wPip and D. immitis in mosquitoes and hence a role for this endosymbiont in influencing vectorial competence is yet to be identified. This study contributes to understanding of wPip distribution in mosquito populations and, to the best of the authors' knowledge, is the first report of natural infections by wPip in Cx. theileri.
Global Health and Tropical Medicine, GHTM, UEI Medical Parasitology, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal.
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Global Health and Tropical Medicine, GHTM, UEI Medical Parasitology, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal.|Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de Lisboa, Lisbon, Portugal.
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Mendes
Global Health and Tropical Medicine, GHTM, UEI Medical Parasitology, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal.
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Maurício
Global Health and Tropical Medicine, GHTM, UEI Medical Parasitology, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal.
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Calado
Global Health and Tropical Medicine, GHTM, UEI Medical Parasitology, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal.
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Novo
Global Health and Tropical Medicine, GHTM, UEI Medical Parasitology, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal.
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Belo
Global Health and Tropical Medicine, GHTM, UEI Medical Parasitology, Instituto de Higiene e Medicina Tropical, IHMT, Universidade Nova de Lisboa, UNL, Lisbon, Portugal.|Department of Medical Virology, Faculty of Health Sciences, Zoonosis Research Unit, University of Pretoria, Pretoria, South Africa.
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Almeida
D000818:Animals; D003465:Culex / Q000382:microbiology* / Q000469:parasitology; D004269:DNA, Bacterial / Q000235:genetics*; D004183:Dirofilaria immitis / Q000302:isolation & purification; D004184:Dirofilariasis / Q000469:parasitology / Q000635:transmission; D006239:Haplotypes; D000072138:Mosquito Vectors / Q000382:microbiology* / Q000469:parasitology; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011174:Portugal; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D020577:Wolbachia / Q000235:genetics / Q000302:isolation & purification*
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S
Culex pipiens; Culex theileri; Portugal; dirofilariasis; mosquito; wPip