scholarly journals Detection of the Japanese encephalitis vector mosquito Culex tritaeniorhynchus in Australia using molecular diagnostics and morphology

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Bryan D. Lessard ◽  
Nina Kurucz ◽  
Juanita Rodriguez ◽  
Jane Carter ◽  
Christopher M. Hardy

Abstract Background Culex (Culex) tritaeniorhynchus is an important vector of Japanese encephalitis virus (JEV) affecting feral pigs, native mammals and humans. The mosquito species is widely distributed throughout Southeast Asia, Africa and Europe, and thought to be absent in Australia. Methods In February and May, 2020 the Medical Entomology unit of the Northern Territory (NT) Top End Health Service collected Cx. tritaeniorhynchus female specimens (n = 19) from the Darwin and Katherine regions. Specimens were preliminarily identified morphologically as the Vishnui subgroup in subgenus Culex. Molecular identification was performed using cytochrome c oxidase subunit 1 (COI) barcoding, including sequence percentage identity using BLAST and tree-based identification using maximum likelihood analysis in the IQ-TREE software package. Once identified using COI, specimens were reanalysed for diagnostic morphological characters to inform a new taxonomic key to related species from the NT. Results Sequence percentage analysis of COI revealed that specimens from the NT shared 99.7% nucleotide identity to a haplotype of Cx. tritaeniorhynchus from Dili, Timor-Leste. The phylogenetic analysis showed that the NT specimens formed a monophyletic clade with other Cx. tritaeniorhynchus from Southeast Asia and the Middle East. We provide COI barcodes for most NT species from the Vishnui subgroup to aid future identifications, including the first genetic sequences for Culex (Culex) crinicauda and the undescribed species Culex (Culex) sp. No. 32 of Marks. Useful diagnostic morphological characters were identified and are presented in a taxonomic key to adult females to separate Cx. tritaeniorhynchus from other members of the Vishnui subgroup from the NT. Conclusions We report the detection of Cx. tritaeniorhynchus in Australia from the Darwin and Katherine regions of the NT. The vector is likely to be already established in northern Australia, given the wide geographical spread throughout the Top End of the NT. The establishment of Cx. tritaeniorhynchus in Australia is a concern to health officials as the species is an important vector of JEV and is now the sixth species from the subgenus Culex capable of vectoring JEV in Australia. We suggest that the species must now be continuously monitored during routine mosquito surveillance programmes to determine its current geographical spread and prevent the potential transmission of exotic JEV throughout Australia. Graphical abstract

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Sunil Dhiman ◽  
Kavita Yadav ◽  
B. N. Acharya ◽  
Raj Kumar Ahirwar ◽  
D. Sukumaran

Abstract Background The direct toxicological impact of insecticides on vector mosquitoes has been well emphasized; however, behavioural responses such as excito-repellency and physical avoidance as a result of insecticide exposure have not been much studied. We have demonstrated the excito-repellency and behavioural avoidance in certain vector mosquito species on exposure to a slow-release insecticidal paint (SRIP) formulation in addition to direct toxicity. Methods A SRIP formulation developed by the Defence Research and Development Establishment, Gwalior, contains chlorpyriphos, deltamethrin and pyriproxyfen as active insecticides. Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti mosquitoes were used to study the excito-repellency response of the formulation. The experiments were performed in a specially designed dual-choice exposure and escape chamber made of transparent polymethyl methacrylate. For the experiments, the SRIP formulation was applied undiluted at a rate of 8 m2 per kg on 15 cm2 metallic surfaces. Mosquitoes were introduced into the exposure chamber, and observations of the movement of mosquitoes into the escape chamber through the exit portal were taken at 1-min intervals for up to 30 min. Results The evaluated formulation displayed strong excito-repellency against all three tested vector mosquito species. Results showed that the ET50 (escape time 50%) for Ae. aegypti, An. stephensi and Cx. quinquefasciatus was 20.9 min, 14.5 min and 17.9 min for contact exposure (CE) respectively. Altogether in CE, the escape rates were stronger in An. stephensi mosquitoes at different time intervals compared to Ae. aegypti and Cx. quinquefasciatus mosquitoes. The probit analysis revealed that the determined ET did not deviate from linearity for both non-contact exposure (NCE) and placebo exposure (PE) (χ2 ≤ 7.9; p = 1.0) for Ae. aegypti mosquitoes and for NCE (χ2 = 8.3; p = 1.0) and PE (χ2 = 1.7; p = 1.0) treatments in Cx. quinquefasciatus. Mortality (24 h) was found to be statistically higher (F = 6.4; p = 0.02) in An. stephensi for CE but did not vary for NCE (p ≥ 0.3) and PE (p = 0.6) treatments among the tested mosquito species. Survival probability response suggested that all the three tested species displayed similar survival responses for similar exposures (χ2 ≤ 2.3; p ≥ 0.1). Conclusion The study demonstrates the toxicity and strong behavioural avoidance in known vector mosquito species on exposure to an insecticide-based paint formulation. The combination of insecticides in the present formulation will broaden the overall impact spectrum for protecting users from mosquito bites. The efficacy data generated in the study provide crucial information on the effectiveness of the tested formulation and could be useful in reducing the transmission intensity and disease risk in endemic countries.


2021 ◽  
pp. 36-43
Author(s):  
Svetala Aleksandrovna Roslavtseva ◽  
◽  
Alla Iosifovna Frolova ◽  
Mikhail Anatol’evich Alekseev ◽  
◽  
...  

Literature on distribution of invasive mosquito species that are vectors of especially dangerous infections (dengue, Chikungunya, Zika, yellow fever, and Japanese encephalitis) in the Europe and Russia was briefly reviewed. Global warming of the climate as well as an increase in the volume of world trade and the biological characteristics of mosquitoes contribute to the widespread of these species on territories of many countries and continents


2020 ◽  
Vol 36 (1) ◽  
pp. 33-36
Author(s):  
Luis F. Hernández-Guevara ◽  
Francisco J. Sánchez-Rámos ◽  
Rahuel J. Chan-Chable ◽  
Luis M. Hernández-Triana ◽  
Ma. Teresa Valdés-Perezgasga ◽  
...  

ABSTRACT Collections of mosquitoes were conducted for the surveillance of species of medical importance in the state of Morelos, Mexico, in June 2017. Species collected included Mansonia (Mansonia) dyari, which was identified using morphological characters and cytochrome c oxidase I DNA barcoding. Although 3 species of genus Mansonia have been previously reported in Mexico, this is the 1st confirmed record of Ma. dyari in Morelos State, where no Mansonia species had been recorded. Historical records of Ma. dyari and Ma. indubitans in Mexico were reviewed. Therefore, this record increases the number of mosquito species occurring in Morelos to 46. The specimens collected in this study were deposited in the Culicidae collection of the Universidad Autónoma Agraria Antonio Narro, Unidad Laguna.


2003 ◽  
Vol 54 (2) ◽  
pp. 155-160 ◽  
Author(s):  
Tomomitsu SATHO ◽  
Yoshio TSUDA ◽  
Pradya SOMBOON ◽  
Hitoshi KAWADA ◽  
Masahiro TAKAGI

2021 ◽  
Vol 27 (11) ◽  
pp. 503-509
Author(s):  
Junyoung Park ◽  
Dong In Kim ◽  
Hyung Wook Kwon ◽  
Woochul Kang

2021 ◽  
Vol 2 (2) ◽  
pp. 133-149
Author(s):  
Aning Kesuma Putri ◽  
Ratu Eva Febriani

The mismatch between jobs and skills indicates the match model in the job market is not going well, which is referred to as (e.g.) labor match, which leads to overeducation and undereducation in the job market. This research was conducted to find the influence of growth, overeducation and undereducation on wages in Southeast Asia. The data used is secondary data sourced from https://ilostat.ilo.org/data/ data in 2010-2019, especially in 8 Southeast Asian countries consisting of Brunai Darusalam, Philippines, Laos, Indonesia, Cambodia, Thailand, Timor Leste and Vietnam. The results found that the workers with the highest undereducated levels were in Timor Laste, then Laos and Cambodia. Worker conditions in developing countries such as Southeast Asia have more undereducation conditions than overeducation. Economic growth, overeducation and undereducatio affect workers' wages. Keywords: overeducation, undereducation, mismatch, labor 


Author(s):  
Barbara Watson Andaya

Southeast Asia includes eleven countries, although this contemporary configuration disguises significant differences, especially in regard to religion and economic status. Theravada Buddhism is dominant in the “mainland” countries of Myanmar (Burma), Thailand, Cambodia, and Laos, while Vietnam is influenced by the religious and intellectual traditions of China, including Mahayana Buddhism, Daoism, and Confucianism. In the “island” areas (Philippines, Malaysia, Singapore, Brunei, Indonesia, and Timor Leste/Timor Lorosae), the dominant faiths are Islam and Christianity (the latter a majority in the Philippines, Timor Leste, and parts of the eastern Indonesian archipelago), with Bali retaining a localized form of Hinduism. There are also marked economic differences. Singapore and Brunei are among the world’s richest countries, with Laos and Timor Leste among the poorest. Despite this diversity, a regional theme concerns the interaction between religious change and commerce. A chronological and comparative approach that moves from early times to the present day shows that ideas about relationships to the cosmos have developed in tandem with expanding commerce. Although this relationship has never been static, the aim of establishing a beneficial interaction with the supranatural world remains a basic human goal. During the 1st millennium ce the rise of new polities, combined with increasing overland and maritime trade, encouraged the adoption and adaption of incoming religions, notably Hinduism and Buddhism. The 13th century marks the beginning of a new phase with the spread of Theravada Buddhism on the mainland and Islam and subsequently Christianity in the island world. The commerce-religion nexus, though still present, is less evident from the mid-19th century to World War II, when all of Southeast Asia except for Thailand was under colonial control. From the late 20th century transnational trade has allied with religious resurgence, generating new and dynamic forms of engaging with nonhuman forces.


ZooKeys ◽  
2018 ◽  
Vol 761 ◽  
pp. 1-177 ◽  
Author(s):  
Ruttapon Srisonchai ◽  
Henrik Enghoff ◽  
Natdanai Likhitrakarn ◽  
Somsak Panha

The dragon millipede genusDesmoxytess.l. is split into five genera, based on morphological characters and preliminary molecular phylogenetic analyses. The present article includes a review ofDesmoxytess.s., while future articles will deal withHylomusCook and Loomis, 1924 and three new genera which preliminarily are referred to as the ‘acantherpestes’, ‘gigas’, and ‘spiny’ groups. Diagnostic morphological characters of each group are discussed.Hylomusis resurrected as a valid genus and the following 33 species are assigned to it:H.asper(Attems, 1937),comb. n.,H.cattienensis(Nguyen, Golovatch & Anichkin, 2005),comb. n.,H.cervarius(Attems, 1953),comb. n.,H.cornutus(Zhang & Li, 1982),comb. n.,H.dracoCook & Loomis, 1924,stat. rev.,H.enghoffi(Nguyen, Golovatch & Anichkin, 2005),comb. n.,H.eupterygotus(Golovatch, Li, Liu & Geoffroy, 2012),comb. n.,H.getuhensis(Liu, Golovatch & Tian, 2014),comb. n.,H.grandis(Golovatch, VandenSpiegel & Semenyuk, 2016),comb. n.,H.hostilis(Golovatch & Enghoff, 1994),comb. n.,H.jeekeli(Golovatch & Enghoff, 1994),comb. n.,H.lingulatus(Liu, Golovatch & Tian, 2014),comb. n.,H.laticollis(Liu, Golovatch & Tian, 2016),comb. n.,H.longispinus(Loksa, 1960),comb. n.,H.lui(Golovatch, Li, Liu & Geoffroy, 2012),comb. n.,H.minutuberculus(Zhang, 1986),comb. n.,H.nodulosus(Liu, Golovatch & Tian, 2014),comb. n.,H.parvulus(Liu, Golovatch & Tian, 2014),comb. n.,H.phasmoides(Liu, Golovatch & Tian, 2016),comb. n.,H.pilosus(Attems, 1937),comb. n.,H.proximus(Nguyen, Golovatch & Anichkin, 2005),comb. n.,H.rhinoceros(Likhitrakarn, Golovatch & Panha, 2015),comb. n.,H.rhinoparvus(Likhitrakarn, Golovatch & Panha, 2015),comb. n.,H.scolopendroides(Golovatch, Geoffroy & Mauriès, 2010),comb. n.,H.scutigeroides(Golovatch, Geoffroy & Mauriès, 2010),comb. n.,H.similis(Liu, Golovatch & Tian, 2016),comb. n.,H.simplex(Golovatch, VandenSpiegel & Semenyuk, 2016),comb. n.,H.simplipodus(Liu, Golovatch & Tian, 2016),comb. n.,H.specialis(Nguyen, Golovatch & Anichkin, 2005),comb. n.,H.spectabilis(Attems, 1937),comb. n.,H.spinitergus(Liu, Golovatch & Tian, 2016),comb. n.,H.spinissimus(Golovatch, Li, Liu & Geoffroy, 2012),comb. n.andH.variabilis(Liu, Golovatch & Tian, 2016),comb. n.Desmoxytess.s. includes the following species:D.breviverpaSrisonchai, Enghoff & Panha, 2016;D.cervina(Pocock,1895);D.delfae(Jeekel, 1964);D.desSrisonchai, Enghoff & Panha, 2016;D.pinnasqualiSrisonchai, Enghoff & Panha, 2016;D.planata(Pocock, 1895);D.purpuroseaEnghoff, Sutcharit & Panha, 2007;D.takensisSrisonchai, Enghoff & Panha, 2016;D.taurina(Pocock, 1895);D.terae(Jeekel, 1964), all of which are re-described based mainly on type material. Two new synonyms are proposed:DesmoxytespterygotaGolovatch & Enghoff, 1994,syn. n.(=Desmoxytescervina(Pocock, 1895)),DesmoxytesrubraGolovatch & Enghoff, 1994,syn. n.(=Desmoxytesdelfae(Jeekel, 1964)). Six new species are described from Thailand:D.aurataSrisonchai, Enghoff & Panha,sp. n.,D.corythosaurusSrisonchai, Enghoff & Panha,sp. n.,D.eurosSrisonchai, Enghoff & Panha,sp. n.,D.flabellaSrisonchai, Enghoff & Panha,sp. n.,D.golovatchiSrisonchai, Enghoff & Panha,sp. n.,D.octoconigeraSrisonchai, Enghoff & Panha,sp. n., as well as one from Malaysia:D.perakensisSrisonchai, Enghoff & Panha,sp. n., and one from Myanmar:D.waepyanensisSrisonchai, Enghoff & Panha,sp. n.The species can mostly be easily distinguished by gonopod structure in combination with other external characters; some cases of particularly similar congeners are discussed. All species ofDesmoxytess.s. seem to be endemic to continental Southeast Asia (except the ‘tramp’ speciesD.planata). Some biological observations (relationship with mites, moulting) are recorded for the first time. Complete illustrations of external morphological characters, an identification key, and distribution maps of all species are provided.


2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Evans Atoni ◽  
Lu Zhao ◽  
Cheng Hu ◽  
Nanjie Ren ◽  
Xiaoyu Wang ◽  
...  

Abstract Mosquito-borne viruses such as Zika virus, Japanese Encephalitis virus and Dengue virus present an increasing global health concern. However, in-depth knowledge of the distribution and diversity of mosquito-associated viruses and their related vectors remains limited, especially for China. To promote their understanding, we present the first comprehensive dataset of the distribution and diversity of these viruses and their related vectors in China (including Taiwan, Hong Kong and Macau). Data was drawn from peer-reviewed journal articles, conference papers and thesis publications in both English and Chinese. Geographical data on mosquito-associated viruses’ occurrence and related mosquito vector species was extracted, and quality-control processes employed. This dataset contains 2,428 accounts of mosquito-associated viruses’ and mosquito species geo-referenced occurrences at various administrative levels in China. The prevalent mosquito-associated virus includes Japanese encephalitis virus, Dengue virus, Banna virus and Culex flavivirus, whereas the abundant mosquito vectors are Culex tritaeryohynchus, Aedes albopictus and Culex pipiens pallens. This geographical dataset delivers a distribution and diversity outline of mosquito-associated viruses in China, and also applicable in various spatial and risk-assessment analysis.


2020 ◽  
Vol 5 (1) ◽  
pp. 9
Author(s):  
Allan Warchot ◽  
Peter Whelan ◽  
John Brown ◽  
Tony Vincent ◽  
Jane Carter ◽  
...  

The Northern Territory Top End Health Service, Medical Entomology Section and the City of Darwin council carry out a joint Mosquito Engineering Program targeting the rectification of mosquito breeding sites in the City of Darwin, Northern Territory, Australia. In 2005, an investigation into potential subterranean stormwater breeding sites in the City of Darwin commenced, specifically targeting roadside stormwater side entry pits. There were 79 side entry pits randomly investigated for mosquito breeding in the Darwin suburbs of Nightcliff and Rapid Creek, with 69.6% of the pits containing water holding sumps, and 45.6% of those water holding sumps breeding endemic mosquitoes. Culex quinquefasciatus was the most common mosquito collected, accounting for 73% of all mosquito identifications, with the potential vector mosquito Aedes notoscriptus also recovered from a small number of sumps. The sumps were also considered potential dry season maintenance breeding sites for important exotic Aedes mosquitoes such as Aedes aegypti and Aedes albopictus, which are potential vectors of dengue, chickungunya and Zika virus. Overall, 1229 side entry pits were inspected in ten Darwin suburbs from 2005 to 2008, with 180 water holding sumps identified and rectified by concrete filling.


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