#Entomological Data and #Detection of #WNV in #Mosquitoes in #Greece (2014–2016), Before Disease Re-Emergence in 2017 (Vector Borne Zoo Dis., abstract)

[Source: Vector Borne and Zoonotic Diseases, full page: (LINK). Abstract, edited.]

Entomological Data and Detection of West Nile Virus in Mosquitoes in Greece (2014–2016), Before Disease Re-Emergence in 2017

Eleni Patsoula, Stavroula Beleri, Nikolaos Tegos, Rima Mkrtsian, Annita Vakali, and Danai Pervanidou

Published Online: 11 Nov 2019 / DOI: https://doi.org/10.1089/vbz.2018.2422

 

Abstract

West Nile virus (WNV) cases were seasonally recorded in humans and animals in Greece, from 2010 to 2014, and circulation of the virus was detected in different Regional Units of the country. Small scale entomological surveillance activities were carried out by several regions and regional units in Greece, during 2014–2016, with the participation of subcontractors for the vector control programs aiming to record presence/absence of mosquito species, and monitor and control mosquito populations. Mosquito traps were placed in rural and urban sites; specimens were collected, morphologically characterized, and pooled by date of collection, location, and species types. Mosquito pools containing Culex pipiens, Aedes caspius, and Aedes albopictus were examined for the presence of WNV and positive pools were detected in different areas of the country. Sequencing of a selected number of amplicons revealed WNV lineage 2 partial NS5 gene sequences. In this study, we present data on the mosquito species composition in the areas of study and WNV detection from several parts of Greece, in 6, 11, and 26 mosquito pools corresponding to the years 2014, 2015, and 2016, respectively. A total of 15 WNV human infections were reported to the public health authorities of the country in 2014, whereas no human cases were detected for 2015–2016. Taking into consideration the complex epidemiological profile of WNV and unforeseen changes in its circulation, re-emergence of WNV human cases in Greece was possible and expected, thus rendering surveillance activities imperative.

Keywords: West Nile Virus; Mosquitoes; Aedes spp.; Culex spp.; Greece.

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#Epidemiologic, #Entomologic, and #Virologic Factors of the 2014–15 #RossRiver Virus #Outbreak, #Queensland, #Australia (Emerg Infect Dis., abstract)

[Source: US Centers for Disease Control and Prevention (CDC), Emerging Infectious Diseases Journal, full page: (LINK). Abstract, edited.]

Volume 25, Number 12—December 2019 / Research

Epidemiologic, Entomologic, and Virologic Factors of the 2014–15 Ross River Virus Outbreak, Queensland, Australia

Cassie C. Jansen, Martin A. Shivas, Fiona J. May, Alyssa T. Pyke, Michael B. Onn, Kerryn Lodo, Sonja Hall-Mendelin, Jamie L. McMahon, Brian L. Montgomery, Jonathan M. Darbro, Stephen L. Doggett, and Andrew F. van den Hurk

Author affiliations: Communicable Diseases Branch, Queensland Government Department of Health, Herston, Queensland, Australia (C.C. Jansen, K. Lodo); Brisbane City Council, Fortitude Valley, Queensland, Australia (M.A. Shivas, M.B. Onn); Metro North Hospital and Health Service, Windsor, Queensland, Australia (F.J. May); Forensic and Scientific Services, Queensland Government Department of Health, Coopers Plains, Queensland, Australia (A.T. Pyke, S. Hall-Mendelin, J.L. McMahon, A.F. van den Hurk); Metro South Hospital and Health Service, Coopers Plains (B.L. Montgomery); Queensland Institute of Medical Research Berghofer, Herston (J.M. Darbro); University of Sydney and Westmead Hospital, Sydney, New South Wales, Australia (S.L. Doggett)

 

Abstract

Australia experienced its largest recorded outbreak of Ross River virus (RRV) during the 2014–15 reporting year, comprising >10,000 reported cases. We investigated epidemiologic, entomologic, and virologic factors that potentially contributed to the scale of the outbreak in Queensland, the state with the highest number of notifications (6,371). Spatial analysis of human cases showed that notifications were geographically widespread. In Brisbane, human case notifications and virus detections in mosquitoes occurred across inland and coastal locations. Viral sequence data demonstrated 2 RRV lineages (northeastern genotypes I and II) were circulating, and a new strain containing 3 unique amino acid changes in the envelope 2 protein was identified. Longitudinal mosquito collections demonstrated unusually high relative abundance of Culex annulirostris and Aedes procax mosquitoes, attributable to extensive freshwater larval habitats caused by early and persistent rainfall during the reporting year. Increased prevalence of these mosquitoes probably contributed to the scale of this outbreak.

Keywords: Ross River Virus; Mosquitoes; Culex spp.; Aedes spp.; Queensland; Australia.

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Vector #Mosquito #Ecology and Japanese #Encephalitis Virus Genotype III Strain Detection from #Culex tritaeniorhynchus and #Pig in Huaihua, #China (Vector Borne Zoo Dis., abstract)

[Source: Vector Borne and Zoonotic Diseases, full page: (LINK). Abstract, edited.]

Vector Mosquito Ecology and Japanese Encephalitis Virus Genotype III Strain Detection from Culex tritaeniorhynchus and Pig in Huaihua, China

Chen Chen, Teng Zhao, Yuting Jiang, Chunxiao Li, Gang Wang, Jian Gao, Yande Dong, Dan Xing, Xiaoxia Guo, and Tongyan Zhao

Published Online: 10 Jun 2019 / DOI: https://doi.org/10.1089/vbz.2019.2453

 

Abstract

The Japanese encephalitis virus (JEV), a mosquito-borne zoonotic pathogen, is the major cause of viral encephalitis worldwide. An investigation of mosquito species diversity, JEV infection rate, and seasonal population fluctuations of Culex tritaeniorhynchus in Huaihua County, Hunan Province, China, revealed the distribution of vector mosquito populations and genotypes and molecular characteristics of current, common JEV strains in this region. Research on mosquito species diversity in different habitats in Huaihua revealed that local community composition was relatively simple, including five species from four genera (two Culex spp., one Anopheles sp., one Aedes sp., and one Armigeres sp.). Cx. tritaeniorhynchuswas clearly the dominant species comprising 94.2–98.6% of all specimens and was always the most common species captured in paddy fields, pigpens, and human dwellings. The seasonal abundance of Cx. tritaeniorhynchus was relatively even, with a single seasonal peak in late August. Two Huaihua JEV strains isolated from the mosquito and pig were highly congruent. The genetic affinities were determined by analyzing capsid/premembrane (C/PrM) and envelope (E) gene variation. The results showed that they were of genotype III and most closely related to the live, attenuated vaccine strains SAl4-14-2 and SA14 and JaGAr01. The Huaihua E protein shares high similarity (mosquito 98.8% and pig 97.6%) at the nucleotide level with the SA14-14-2 vaccine. Although we found that the E gene sequences of the Huaihua JEV mosquito strain and pig strain have 11 and 15 amino acid site substitutions compared with the SAl4-14-2 vaccine, key sites that associated with JEV’s antigenic activity and neurovirulence were unchanged. The SA14-14-2 vaccine should therefore be effective in preventing JEV infection in the Huaihua region.

Keywords: Japanese Encephalitis Virus; Mosquitoes; Culex spp.; Pigs; China.

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#Arboviral #screening of invasive #Aedes species in northeastern #Turkey: #WNV circulation and detection of insect-only viruses (PLoS Negl Trop Dis., abstract)

[Source: PLoS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Arboviral screening of invasive Aedes species in northeastern Turkey: West Nile virus circulation and detection of insect-only viruses

Mustafa M. Akıner, Murat Öztürk, Aykut Buğra Başer, Filiz Günay, Sabri Hacıoğlu, Annika Brinkmann, Nergis Emanet, Bülent Alten, Aykut Özkul, Andreas Nitsche, Yvonne-Marie Linton, Koray Ergünay

Published: May 6, 2019 / DOI: https://doi.org/10.1371/journal.pntd.0007334 / This is an uncorrected proof.

 

Abstract

Background

The recent reports of Aedes aegypti and Ae. albopictus populations in Turkey, in parallel with the territorial expansion identified in several surrounding countries, have raised concerns about the establishment and re-establishment of these invasive Aedes mosquitoes in Turkey. This cross-sectional study was performed to detect Aedes aegypti and Ae. albopictus in regions of recent incursions, and screen for viral pathogens known to be transmitted elsewhere by these species.

Methodology

Mosquitoes were collected at several locations in Artvin, Rize and Trabzon provinces of the Black Sea region during 2016–2017, identified morphologically, pooled and analyzed via generic or specific nucleic acid amplification assays. Viruses in positive pools were identified by product sequencing, cell culture inoculation and next generation sequencing (NGS) in selected specimens.

Principal findings

The study group comprised 791 specimens. Aedes albopictus was the most abundant species in all locations (89.6%), followed by Ae. aegypti (7.8%) and Culex pipiens (2.5%). Mosquitoes were screened for viruses in 65 pools where fifteen (23.1%) were reactive. The infecting strains was identified as West Nile virus (WNV) in 5 pools (7.7%) with Ae. albopictus or Cx. pipiensmosquitoes. The obtained WNV sequences phylogenetically grouped with local and global lineage 1 clade 1a viruses. In 4 (6.2%) and 6 (9.2%) pools, respectively, cell fusing agent virus (CFAV) and Aedes flavivirus (AEFV) sequences were characterized. NGS provided a near-complete AEFV genome in a pool of Ae. albopictus. The strain is provisionally called “AEFV-Turkey”, and functional analysis of the genome revealed several conserved motifs and regions associated with virus replication. Merida-like virus Turkey (MERDLVT), a recently-described novel rhabdovirus, was also co-detected in a Cx. pipiens pool also positive for WNV.

Conclusions/Significance

Invasive Aedes mosquitoes are established in certain locations of northeastern Turkey. Herein we conclusively show the role of these species in WNV circulation in the region. Biosurveillance is imperative to monitor the spread of these species further into Asia Minor and to detect possible introduction of pathogens.

 

Author summary

Mosquitoes can transmit viruses to susceptible humans during blood-feeding. The presence and establishment of particular mosquito species within a region is the prerequisite for the introduction and emergence of the diseases transmitted by that species. Aedes mosquitoes transmit dengue and yellow fever, as well as recently-emergent chikungunya and Zika viruses to susceptible humans. Mosquitoes were collected in the Black Sea region of Anatolia, NE Turkey, where invasive Aedes mosquitoes have recently encroached, and specimens were screened for a variety of viruses. We observed particular Aedes species that are associated with disease transmission, suggesting that these species have been established in the region. We did not detect dengue, yellow fever, chikungunya or Zika viruses, but West Nile virus was found in several pools of these invasive species. Moreover, we detected a number of related viruses that exclusively infect mosquitoes, identified for the first time in Anatolia. Using advanced sequencing technologies, the near-complete genome of a new Aedes flavivirus (AEFV-Turkey) was achieved.

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Citation: Akıner MM, Öztürk M, Başer AB, Günay F, Hacıoğlu S, Brinkmann A, et al. (2019) Arboviral screening of invasive Aedes species in northeastern Turkey: West Nile virus circulation and detection of insect-only viruses. PLoS Negl Trop Dis 13(5): e0007334. https://doi.org/10.1371/journal.pntd.0007334

Editor: Pattamaporn Kittayapong, Faculty of Science, Mahidol University, THAILAND

Received: January 3, 2019; Accepted: March 26, 2019; Published: May 6, 2019

This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Data Availability: The nucleotide sequences characterized in this study are deposited and can be accessed at the GenBank via the following accession numbers: MF361262, MF361264, MF361265, MF361263, MF361267, MF361268, MK251047, MK251048, MK251049, MK251050, MK251051, MK251052, MK251053, MK251054, MK251055 and MK251056. All remaining data are within the paper and its Supporting Information files.

Funding: This study was supported in part by the Armed Forces Health Surveillance Board, Global Emerging Infections Surveillance and Response System (AFHSB-GEIS), United States of America (FY18 award P0034_18_WR (PI: Yvonne-Marie Linton) under US Army subcontract W911QY-16-C-0160). BA and FG were also included in AIM-COST. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The material to be published reflects the views of the authors and should not be construed to represent those of the US Department of the Army or the US Department of Defense.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Flavivirus; Rhabdovirus; Mosquitoes; WNV; Aedes albopictus; Culex spp.; Turkey; Merida-like Turkey virus.

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New #strains of Japanese #encephalitis virus circulating in #Shanghai, #China after a ten-year hiatus in local #mosquito #surveillance (Parasit Vectors, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Parasit Vectors. 2019 Jan 9;12(1):22. doi: 10.1186/s13071-018-3267-9.

New strains of Japanese encephalitis virus circulating in Shanghai, China after a ten-year hiatus in local mosquito surveillance.

Fang Y1, Zhang Y2, Zhou ZB1, Xia S1, Shi WQ1, Xue JB1, Li YY1, Wu JT1.

Author information: 1 National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 20025, People’s Republic of China. 2 National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; WHO Collaborating Centre for Tropical Diseases; National Center for International Research on Tropical Diseases, Ministry of Science and Technology; Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, 20025, People’s Republic of China. zhang1972003@163.com.

 

Abstract

BACKGROUND:

Continuous vector pathogen surveillance is essential for preventing outbreaks of mosquito-borne diseases. Several mosquito species acting as vectors of Japanese encephalitis virus (JEV), dengue virus, Zika virus, malaria parasites and other pathogens are primary mosquito species in Shanghai, China. However, few surveys of human pathogenic arboviruses in mosquitoes in Shanghai have been reported in the last ten years. Therefore, in this study, we evaluated mosquito activity in Shanghai, China during 2016 and tested for the presence of alphaviruses, flaviviruses, orthobunyaviruses and several parasitic pathogens.

RESULTS:

Five pooled samples were JEV-positive [4/255 pools of Culex tritaeniorhynchus and 1/256 pools of Cx. pipiens (s.l.)] based on analysis of the NS5 gene. Alphaviruses, orthobunyaviruses, Plasmodium and filariasis were not found in this study. Phylogenetic and molecular analyses revealed that the JEV strains belonged to genotype I. Moreover, newly detected Shanghai JEV strains were genetically close to previously isolated Shandong strains responsible for transmission during the 2013 Japanese encephalitis (JE) outbreak in Shandong Province, China but were more distantly related to other Shanghai strains detected in the early 2000s. The E proteins of the newly detected Shanghai JEV strains differed from that in the live attenuated vaccine SA14-14-2-derived strain at six amino residues: E130 (Ile→Val), E222 (Ala→Ser), E327 (Ser→Thr), E366 (Arg→Ser/Pro), E393 (Asn→Ser) and E433 (Val→Ile). However, no differences were observed in key amino acid sites related to antigenicity. Minimum JEV infection rates were 1.01 and 0.65 per 1000 Cx. tritaeniorhynchus and Cx. pipiens (s.l.), respectively.

CONCLUSIONS:

Five new Shanghai JEV genotype I strains, detected after a ten-year hiatus in local mosquito surveillance, were genetically close to strains involved in the 2013 Shandong JE outbreak. Because JEV is still circulating, vaccination in children should be extensively and continuously promoted. Moreover, JEV mosquito surveillance programmes should document the genotype variation, intensity and distribution of circulating viruses for use in the development and implementation of disease prevention and control strategies.

KEYWORDS: Culex pipiens; Culex tritaeniorhynchus; Japanese encephalitis; Mosquito-borne diseases; SA14-14-2

PMID: 30626442 DOI: 10.1186/s13071-018-3267-9

Keywords: Japanese Encephalitis; Arbovirus; Mosquitoes; China; Shanghai; Culex spp.

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#Construction sites in #Miami-Dade County, #Florida are highly favorable #environments for vector #mosquitoes (PLoS One, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

PLoS One. 2018 Dec 20;13(12):e0209625. doi: 10.1371/journal.pone.0209625. eCollection 2018.

Construction sites in Miami-Dade County, Florida are highly favorable environments for vector mosquitoes.

Wilke ABB1, Vasquez C2, Petrie W2, Caban-Martinez AJ1, Beier JC1.

Author information: 1 Department of Public Health Sciences, Miller School of Medicine, University of Miami, Miami, FL, United States of America. 2 Miami-Dade County Mosquito Control Division, Miami, FL, United States of America.

 

Abstract

Urbanization is increasing globally, and construction sites are an integral part of the urbanization process. It is unknown to what extent construction sites create favorable breeding conditions for mosquitoes. The main objectives of the present study were to identify what species of mosquitoes are present at construction sites and the respective physical features associated with their production. Eleven construction sites were cross-sectionally surveyed for the presence of mosquitoes in Miami-Dade County, Florida including in areas previously affected by the Zika virus outbreak in 2016. A total of 3.351 mosquitoes were collected; 2.680 adults and 671 immatures. Aedes aegypti and Culex quinquefasciatus comprised 95% of all collected mosquitoes and were the only species found in their immature forms breeding inside construction sites. Results for the Shannon and Simpson indices, considering both immature and adult specimens, yielded the highest values for Cx. quinquefasciatus and Ae. aegypti. The individual rarefaction curves indicated that sampling sufficiency was highly asymptotic for Cx. quinquefasciatus and Ae. aegypti, and the plots of cumulative species abundance (ln S), Shannon index (H) and log evenness (ln E) (SHE) revealed the lack of heterogeneity of species composition, diversity and evenness for the mosquitoes found breeding in construction sites. The most productive construction site breeding features were elevator shafts, Jersey plastic barriers, flooded floors and stair shafts. The findings of this study indicate that vector mosquitoes breed in high numbers at construction sites and display reduced biodiversity comprising almost exclusively Ae. aegypti and Cx. quinquefasciatus. Such findings suggest that early phase construction sites have suitable conditions for the proliferation of vector mosquitoes. More studies are needed to identify modifiable worker- and organizational-level factors to improve mosquito control practices and guide future mosquito control strategies in urban environments.

PMID: 30571764 DOI: 10.1371/journal.pone.0209625

Keywords: Mosquitoes; Aedes spp.; Culex spp.; Aedes aegypti; Culex quinquefasciatus; USA; Florida.

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Vertical #transmission of naturally occurring #Bunyamwera and insect-specific #flavivirus #infections in #mosquitoes from islands and mainland shores of Lakes Victoria and Baringo in #Kenya (PLoS Negl Trop Dis., abstract)

[Source: PLoS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Vertical transmission of naturally occurring Bunyamwera and insect-specific flavivirus infections in mosquitoes from islands and mainland shores of Lakes Victoria and Baringo in Kenya

Yvonne Ukamaka Ajamma, Thomas Ogao Onchuru , Daniel O. Ouso , David Omondi, Daniel K. Masiga, Jandouwe Villinger

Published: November 19, 2018 / DOI: https://doi.org/10.1371/journal.pntd.0006949 / This is an uncorrected proof.

 

Abstract

Background

Many arboviruses transmitted by mosquitoes have been implicated as causative agents of both human and animal illnesses in East Africa. Although epidemics of arboviral emerging infectious diseases have risen in frequency in recent years, the extent to which mosquitoes maintain pathogens in circulation during inter-epidemic periods is still poorly understood. This study aimed to investigate whether arboviruses may be maintained by vertical transmission via immature life stages of different mosquito vector species.

Methodology

We collected immature mosquitoes (egg, larva, pupa) on the shores and islands of Lake Baringo and Lake Victoria in western Kenya and reared them to adults. Mosquito pools (≤25 specimens/pool) of each species were screened for mosquito-borne viruses by high-resolution melting analysis and sequencing of multiplex PCR products of genus-specific primers (alphaviruses, flaviviruses, phleboviruses and Bunyamwera-group orthobunyaviruses). We further confirmed positive samples by culturing in baby hamster kidney and Aedes mosquito cell lines and re-sequencing.

Principal findings

Culex univittatus (2/31pools) and Anopheles gambiae (1/77 pools) from the Lake Victoria region were positive for Bunyamwera virus, a pathogenic virus that is of public health concern. In addition, Aedes aegypti (3/50), Aedes luteocephalus (3/13), Aedes spp. (2/15), and Culex pipiens (1/140) pools were positive for Aedes flaviviruses at Lake Victoria, whereas at Lake Baringo, three pools of An. gambiae mosquitoes were positive for Anopheles flavivirus. These insect-specific flaviviruses (ISFVs), which are presumably non-pathogenic to vertebrates, were found in known medically important arbovirus and malaria vectors.

Conclusions

Our results suggest that not only ISFVs, but also a pathogenic arbovirus, are naturally maintained within mosquito populations by vertical transmission, even in the absence of vertebrate hosts. Therefore, virus and vector surveillance, even during inter-epidemics, and the study of vector-arbovirus-ISFV interactions, may aid in identifying arbovirus transmission risks, with the potential to inform control strategies that lead to disease prevention.

 

Author summary

The East African region is endemic to diverse mosquito-transmitted arboviruses, though little is known about the role of vertical transmission in maintaining these viruses within mosquito vector populations during inter-epidemic periods. We sampled mosquito larvae from the Lake Baringo and Lake Victoria regions of Kenya and reared them to adults in the laboratory before screening them for mosquito-associated viruses by multiplex RT-PCR-HRM, cell culture, and sequencing. From the Lake Victoria region, we detected the arbovirus, Bunyamwera, which can cause febrile illness in humans, in Culex univittatus and vector competent Anopheles gambiaemosquitoes. We also identified diverse insect-specific flaviviruses in Aedes aegypti, Aedes luteocephalus, Aedes spp. and Culex pipiens mosquitoes. From the Lake Baringo region, we detected Anopheles flavivirus in An. gambiae mosquitoes. These findings demonstrate that naturally occurring vertical transmission potentially maintains viruses in circulation within the sampled vector species populations. Therefore, mosquitoes may potentially transmit a pathogenic arbovirus during their first bite after emergence. Because various insect-specific flaviviruses have recently been found to either inhibit or enhance replication of specific arboviruses in mosquitoes, their vertical transmission, as observed in this study, has implications as to their potential impact on both horizontal and vertical transmission of medically important arboviruses.

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Citation: Ajamma YU, Onchuru TO, Ouso DO, Omondi D, Masiga DK, Villinger J (2018) Vertical transmission of naturally occurring Bunyamwera and insect-specific flavivirus infections in mosquitoes from islands and mainland shores of Lakes Victoria and Baringo in Kenya. PLoS Negl Trop Dis 12(11): e0006949. https://doi.org/10.1371/journal.pntd.0006949

Editor: Michael J. Turell, INDEPENDENT RESEARCHER, UNITED STATES

Received: May 3, 2018; Accepted: October 26, 2018; Published: November 19, 2018

Copyright: © 2018 Ajamma et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All ISFV sequences are available from the GenBank nucleotide database (accession MG372051-MG372060, MK015647- MK015648).

Funding: This work was supported by the Swedish International Development Cooperation Agency (Sida) (www.sida.se), grant number 75000529 to YUA as an African Regional Postgraduate Programme in Insect Science (ARPPIS) scholar; and institutional financial support from UK Aid (www.ukaiddirect.org) from the UK Government; Sida; the Swiss Agency for Development and Cooperation (SDC) (www.eda.admin.ch/sdc); and the Kenyan Government (www.mygov.go.ke). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The views expressed herein do not necessarily reflect the official opinion of the donors.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Arbovirus; Flavivirus; Orthobunyavirus; Bunyamwera Virus; Mosquitoes; Culex spp.; Anopheles spp.; Kenya.

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