Wolbachia infection and genotyping in Aedes albopictus / 上海预防医学

ObjectiveTo investigate the infection and genotypes of Wolbachia in Aedes albopictus. MethodsAdult and larval samples of Aedes albopictus were collected from different residential and wild areas from 2020 to 2021， Wolbachia surface protein （wsp） gene was amplified and genotyped for wAlbA and wAlbB by PCR， and sequenced for phylogenetic analysis. The difference of detection rate among different habitats， male and female adult mosquitoes， adult and larvae was compared by χ2 analysis. ResultsThe detection rate of Wolbachia in adult and larvae of Aedes albopictus were 43.5% （77/177） and 70.4% （190/270）， respectively， with a statistically significant difference （χ2=32.086，P<0.001）， and wAlbA and wAlbB were mainly detected together. The detection rate of Wolbachia in female and male Aedes albopictus were 50.7% （76/150） and 3.7% （1/27）， respectively， with a statistically significant difference（χ2=20.533，P<0.001）. The detection rate of adult Aedes albopictus in Songjiang wild area， residential area and Hongkou residential area were 91.7% （55/60）， 18.8% （22/117） and 41.7% （30/72）， respectively， with a statistically significant difference （χ2=54.322，P<0.001）. Genotyping and phylogenetic analysis showed that adult and larvae of Aedes albopictus infected with Wolbachia were mainly wAlb A and wAlb B. In addition， some sequences formed clades independently， and the genetic distance from other sequences was relatively large. ConclusionInfection of Wolbachia in Aedes albopictus is relatively common in Songjiang District. The main genotypes are wAlb A and wAlb B and there may be other subtypes， which are worthy of further exploration and research.

Molecular detection and phylogenetic analysis of Wolbachia infection in common mosquito species in Henan Province / 中国血吸虫病防治杂志

Objective To investigate the infection and genotypes of Wolbachia in common mosquito species in Henan Province, so as to provide insights into management of mosquito-borne diseases. Methods Aedes, Culex and Anopheles samples were collected from cowsheds, sheepfolds and human houses in Puyang, Nanyang City and Xuchang cities of Henan Province from July to September, 2022, and the infection of Wolbachia was detected. The 16S rDNA and wsp genes of Wolbachia were amplified and sequenced. Sequence alignment was performed using the BLAST software, and the obtained 16S rDNA gene sequence was compared with the sequence of the 16S rDNA gene in GenBank database. In addition, the phylogenetic trees were created based on 16S rDNA and wsp gene sequences using the software MEGA 11.0. Results A total 506 female adult mosquitoes were collected from three sampling sites in Nanyang, Xuchang City and Puyang cities from July to September, 2022. The overall detection of Wolbachia was 45.1% (228/506) in mosquitoes, with a higher detection rate in A. albopictus than in Cx. pipiens pallens [97.9% (143/146) vs. 50.6% (85/168); χ2 = 88.064, P < 0.01]. The detection of Wolbachia in Cx. pipiens pallens was higher in Xuchang City (96.8%, 62/64) than in Nanyang (15.6%, 7/45) and Puyang cities (27.1%, 16/59) (χ2 = 89.950, P < 0.01). The homologies of obtained Wolbachia 16S rDNA and wsp gene sequences were 95.3% to 100.0% and 81.7% to 99.8%. Phylogenetic analysis based on wsp gene sequences showed Wolbachia supergroups A and B in mosquito samples, with wAlbA and wMors strains in supergroup A and wPip and wAlbB strains in supergroup B. Wolbachia strain wAlbB infection was detected in A. albopictus in Puyang and Nanyang Cities, while Wolbachia strain wPip infection was identified in A. albopictus in Xuchang City. Wolbachia strain wAlbA infection was detected in Cx. pipiens pallens sampled from three cities, and one Cx. pipiens pallens was found to be infected with Wolbachia strain wMors in Nanyang City. Conclusions Wolbachia infection is commonly prevalent in Ae. albopictus and Cx. pipiens pallens from Henan Province, and Wolbachia strains wAlbB and wAlbA are predominant in Ae. albopictus, while wPip strain is predominant in Cx. pipiens pallens. This is the first report to present Wolbachia wMors strain infection in Cx. pipiens pallens in Henan Province.

Detection of Wolbachia pipientis, including a new strain containing the wsp gene, in two sister species of Paraphlebotomus sandflies, potential vectors of zoonotic cutaneous leishmaniasis

Individual, naturally occurring Phlebotomus mongolensis and Phlebotomus caucasicus from Iran were screened for infections with the maternally inherited intracellular Rickettsia-like bacterium Wolbachia pipientis via targeting a major surface protein gene (wsp). The main objective of this study was to determine if W. pipientis could be detected in these species. The sandflies were screened using polymerase chain reaction to amplify a fragment of the Wolbachia surface protein gene. The obtained sequences were edited and aligned with database sequences to identify W. pipientis haplotypes. Two strains of Wolbachia were found. Strain Turk 54 (accession EU780683) is widespread and has previously been reported in Phlebotomus papatasi and other insects. Strain Turk 07 (accession KC576916) is a novel strain, found for first time in the two sister species. A-group strains of W. pipientis occur throughout much of the habitat of these sandflies. It is possible that Wolbachia is transferred via horizontal transmission. Horizontal transfer could shed light on sandfly control because Wolbachia is believed to drive a deleterious gene into sandflies that reduces their natural population density. With regard to our findings in this study, we can conclude that one species of sandfly can be infected with different Wolbachia strains and that different species of sandflies can be infected with a common strain.