scholarly journals Molecular detection and identification of Culex flavivirus in mosquito species from Jeju, Republic of Korea

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Shilpa Chatterjee ◽  
Choon-Mee Kim ◽  
Na Ra Yun ◽  
Dong-Min Kim ◽  
Hyeon Je Song ◽  
...  

Abstract Background Mosquito-borne flaviviruses are prime pathogens and have been a major hazard to humans and animals. They comprise several arthropod-borne viruses, including dengue virus, yellow fever virus, Japanese encephalitis virus, and West Nile virus. Culex flavivirus (CxFV) is a member of the insect-specific flavivirus (ISF) group belonging to the genus Flavivirus, which is widely distributed in a variety of mosquito populations. Methods Viral nucleic acid was extracted from adult mosquito pools and subjected to reverse transcriptase nested polymerase chain reaction (PCR) using target-specific primers for detecting CxFV nonstructural protein 5 (NS5). The PCR-positive samples were then sequenced, and a phylogenetic tree was constructed, including reference sequences obtained from GenBank. Results 21 pools, belonging to Culex pipiens pallens (Cx. p. pallens) were found to be positive for the CxFV RNA sequence, with a minimum infection rate of 14.5/1000 mosquitoes. The phylogenetic analysis of the NS5 protein sequences indicated that the detected sequences were closely related to strains identified in China, with 95–98% sequence similarities. Conclusion Our findings highlight the presence of CxFV in Cx. p. pallens mosquito species in Jeju province, Republic of Korea. This is the first study reporting the prevalence of CxFV in Culex Pipiens (Cx. pipiens) host in the Jeju province, which can create possible interaction with other flaviviruses causing human and animal diseases. Although, mosquito-borne disease causing viruses were not identified properly, more detailed surveillance and investigation of both the host and viruses are essential to understand the prevalence, evolutionary relationship and genetic characteristic with other species.

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Shilpa Chatterjee ◽  
Choon‑Mee Kim ◽  
Na Ra Yun ◽  
Dong‑Min Kim ◽  
Hyeon Je Song ◽  
...  

2020 ◽  
Vol 14 (1) ◽  
pp. 81-88
Author(s):  
Fedor I. Vasilevich ◽  
Anna M. Nikanorova

The purpose of the research is development of preventive measures against zooanthroponoze vector-borne diseases spread by parasitic arthropods in the Kaluga Region. Materials and methods. The subject of the research was Ixodidae, mosquitoes, and small mammals inhabiting the Kaluga Region. The census of parasitic arthropods was carried out on the territory of all districts of the Kaluga Region and the city of Kaluga. Open natural habitat and human settlements were investigated. Weather conditions from 2013 to 2018 were also taken into account. For the purposes of the study, we used standard methods for capturing and counting arthropods and mouse-like rodents. In order to obtain mathematical models of small mammal populations, a full factorial experiment was conducted using the collected statistical data. In-process testing of the drug based on s-fenvalerate and piperonyl butoxide were carried out under the conditions of the agricultural collective farm “Niva” of the Kozelsky District, the Kaluga Region, and LLC “Angus Center of Genetics” of the Babyninsky District, the Kaluga Region. Results and discussion. In the Kaluga Region, two species of ixodic ticks are found, namely, Ixodes ricinus and Dermacentor reticulatus, which have two activity peaks. Mosquito may have 3-4 generations in a year in the Kaluga region. The most common mosquito species in the Kaluga Region are Aedes communis, Ae. (Och.) togoi and Ae. (Och.) diantaeus, Culex pipiens Culex Linnaeus, 1758 (Diptera, Culicidae) (Culex pipiens): Cx. pipiens f. pipiens L. (non-autogenic form) and Cx. p. f. molestus Fors. (autogenic form), which interbreed, and reproductively isolated in the Region. The developed mathematical models make it possible to quantify the risks of outbreaks of zooanthroponoze vector-borne diseases without the cost of field research, and allow for rational, timely and effective preventive measures. Medications based on s-fenvalerate and piperonyl butoxide and based on cyfluthrin showed high insecto-acaricidal efficacy and safety.


Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1475
Author(s):  
Moussa Moïse Diagne ◽  
Marie Henriette Dior Ndione ◽  
Alioune Gaye ◽  
Mamadou Aliou Barry ◽  
Diawo Diallo ◽  
...  

Yellow fever virus remains a major threat in low resource countries in South America and Africa despite the existence of an effective vaccine. In Senegal and particularly in the eastern part of the country, periodic sylvatic circulation has been demonstrated with varying degrees of impact on populations in perpetual renewal. We report an outbreak that occurred from October 2020 to February 2021 in eastern Senegal, notified and managed through the synergistic effort yellow fever national surveillance implemented by the Senegalese Ministry of Health in collaboration with the World Health Organization, the countrywide 4S network set up by the Ministry of Health, the Institut Pasteur de Dakar, and the surveillance of arboviruses and hemorrhagic fever viruses in human and vector populations implemented since mid 2020 in eastern Senegal. Virological analyses highlighted the implication of sylvatic mosquito species in virus transmission. Genomic analysis showed a close relationship between the circulating strain in eastern Senegal, 2020, and another one from the West African lineage previously detected and sequenced two years ago from an unvaccinated Dutch traveler who visited the Gambia and Senegal before developing signs after returning to Europe. Moreover, genome analysis identified a 6-nucleotide deletion in the variable domain of the 3′UTR with potential impact on the biology of the viral strain that merits further investigations. Integrated surveillance of yellow fever virus but also of other arboviruses of public health interest is crucial in an ecosystem such as eastern Senegal.


Insects ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 269
Author(s):  
Eleanor N. Field ◽  
Ryan E. Tokarz ◽  
Ryan C. Smith

The ecology and environmental conditions of a habitat have profound influences on mosquito population abundance. As a result, mosquito species vary in their associations with particular habitat types, yet long-term studies showing how mosquito populations shift in a changing ecological landscape are lacking. To better understand how land use changes influence mosquito populations, we examined mosquito surveillance data over a thirty-four-year period for two contrasting sites in central Iowa. One site displayed increasing levels of urbanization over time and a dramatic decline in Culex pipiens group (an informal grouping of Culex restuans, Culex pipiens, and Culex salinarius, referred to as CPG), the primary vectors of West Nile virus in central Iowa. Similar effects were also shown for other mosquito vector populations, yet the abundance of Aedes vexans remained constant during the study period. This is in contrast to a second site, which reflected an established urban landscape. At this location, there were no significant changes in land use and CPG populations remained constant. Climate data (temperature, total precipitation) were compiled for each location to see if these changes could account for altered population dynamics, but neither significantly influence CPG abundance at the respective site locations. Taken together, our data suggest that increased landscape development can have negative impacts on Culex vector populations, and we argue that long-term surveillance paired with satellite imagery analysis are useful methods for measuring the impacts of rapid human development on mosquito vector communities. As a result, we believe that land use changes can have important implications for mosquito management practices, population modeling, and disease transmission dynamics.


2020 ◽  
Author(s):  
Triwibowo Ambar Garjito ◽  
Lulus Susanti ◽  
Mujiyono Mujiyono ◽  
Mega Tyas Prihatin ◽  
Dwi Susilo ◽  
...  

Abstract BackgroundSeveral methods exist to collect and assess the abundance of dengue vector mosquitoes, i.e. morning adult collection using an aspirator, pupal collection, various ovitraps, whole night collection using human landing methods, and larval collection. This diversity of methods might be a source of variability and lack of statistical significance when trying to correlate mosquito density and risk of dengue outbreak. There is also a lack of published data regarding the effectiveness of these methods MethodsA mosquito survey was conducted in 39 locations corresponding to 15 dengue endemic provinces in Indonesia. The larval surveys were performed by collecting at least a single Aedes larva from each container, and then reared up until hatching. Three adult mosquito sampling methods were also used, including morning resting collection, human landing collection, animal baited trap. All field samples were tested for dengue. Factor Analysis of Mixed Data (FAMD) was conducted to analyze the effectiveness of the collection methods against mosquito species and dengue incidence.ResultsA total of 44,675 mosquitoes were collected. The single larva method was the most efficient method. Out of a total of 89 dengue-positive pools, the most frequently encountered virus was DENV2, which made up half of the positive samples, followed by DENV3 and DENV1, respectively. FAMD showed that no correlation could be found between any methods and the presence of dengue virus in mosquitoes. Moreover, no correlation could be found between either any methods or the incidence.ConclusionsThere was no concistency in the efficacy of a given method and the incidence of dengue in the human population. There was no correlation between any of the parameters considered, i.e. method, incidence of dengue, location and presence of dengue virus in mosquitoes. This indicates that entomological factors are not reliable indicators.


2009 ◽  
Vol 83 (18) ◽  
pp. 9195-9205 ◽  
Author(s):  
Dipankar Bhattacharya ◽  
Mayuri ◽  
S. M. Best ◽  
R. Perera ◽  
R. J. Kuhn ◽  
...  

ABSTRACT Serine/threonine phosphorylation of the nonstructural protein 5 (NS5) is a conserved feature of flaviviruses, but the kinase(s) responsible and function(s) remain unknown. Mass spectrometry was used to compare the phosphorylation sites of the NS5 proteins of yellow fever virus (YFV) and dengue virus (DENV), two flaviviruses transmitted by mosquitoes. Seven DENV phosphopeptides were identified, but only one conserved phosphoacceptor site (threonine 449 in DENV) was identified in both viruses. This site is predicted to be a protein kinase G (PKG) recognition site and is a strictly conserved serine/threonine phosphoacceptor site in mosquito-borne flaviviruses. In contrast, in tick-borne flaviviruses, this residue is typically a histidine. A DENV replicon engineered to have the tick-specific histidine residue at this position is replication defective. We show that DENV NS5 purified from Escherichia coli is a substrate for PKG in vitro and facilitates the autophosphorylation of PKG as seen with cellular substrates. Phosphorylation in vitro by PKG also occurs at threonine 449. Activators and inhibitors of PKG modulate DENV replication in cell culture but not replication of the tick-borne langat virus. Collectively, these data argue that PKG mediates a conserved serine/threonine phosphorylation event specifically for flaviviruses spread by mosquitoes.


Viruses ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1033 ◽  
Author(s):  
Pettersson ◽  
Shi ◽  
Eden ◽  
Holmes ◽  
Hesson

Mosquitoes harbor an extensive diversity of ‘insect-specific’ RNA viruses in addition to those important to human and animal health. However, because most studies of the mosquito virome have been conducted at lower latitudes, little is known about the diversity and evolutionary history of RNA viruses sampled from mosquitoes in northerly regions. Here, we compared the RNA virome of two common northern mosquito species, Culex pipiens and Culex torrentium, collected in south-central Sweden. Following bulk RNA-sequencing (meta-transcriptomics) of 12 libraries, comprising 120 specimens of Cx. pipiens and 150 specimens of Cx. torrentium, we identified 40 viruses (representing 14 virus families) of which 28 were novel based on phylogenetic analysis of the RNA-dependent RNA polymerase (RdRp) protein. Hence, we documented similar levels of virome diversity as in mosquitoes sampled from the more biodiverse lower latitudes. Many viruses were also related to those sampled on other continents, indicative of a widespread global movement and/or long host–virus co-evolution. Although the two mosquito species investigated have overlapping geographical distributions and share many viruses, several viruses were only found at a specific location at this scale of sampling, such that local habitat and geography may play an important role in shaping viral diversity in Culex mosquitoes.


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.


Sign in / Sign up

Export Citation Format

Share Document