#Sequencing of #ZIKV #genomes directly from Ae. aegypti and Cx. quinquefasciatus #mosquitoes collected during the 2015-16 #epidemics in #Recife (Infect Genet Evol., abstract)

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

Infect Genet Evol. 2020 Jan 6:104180. doi: 10.1016/j.meegid.2020.104180. [Epub ahead of print]

Sequencing of ZIKV genomes directly from Ae. aegypti and Cx. quinquefasciatus mosquitoes collected during the 2015-16 epidemics in Recife.

Paiva MHS1, Guedes DRD2, Krokovsky L2, Machado LC2, Rezende TMT2, de Morais Sobral MC2, Ayres CFJ2, Wallau GL3.

Author information: 1 Universidade Federal de Pernambuco, Caruaru, Brazil. 2 Entomology Department of the Aggeu Magalhães Institute, Oswaldo Cruz Foundation, Recife, Pernambuco, Brazil. 3 Entomology Department of the Aggeu Magalhães Institute, Oswaldo Cruz Foundation, Recife, Pernambuco, Brazil. Electronic address: gabriel.wallau@cpqam.fiocruz.br.

 

Abstract

Zika virus (ZIKV) is a negative sense RNA virus from the Flaviviridae family, which was relatively unknown until the first human epidemic in Micronesia, in 2007. Since its spread to French Polynesia and the Americas. Recife, the capital of Pernambuco state and epicenter of the Zika epidemic in Brazil, experienced a large number of microcephaly cases and other congenital abnormalities associated to the ZIKV infection from, 2015 to 16. Evidences suggest that both Aedes aegypti and Culex quinquefasciatus mosquitoes from Recife are capable of replicating and transmitting the virus. Here, we conducted high throughput sequencing of ZIKV genomes directly from Ae. aegypti and Cx. quinquefasciatus mosquitoes collected during the ZIKV epidemics in Recife, in order to investigate the variability and evolution of the virus. We obtained 11 draft ZIKV genomes derived from 5 pools from each Ae. aegypti and Cx. quinquefasciatus species. Genome coverage breadth ranged from 16 to 100% and average depth from 45 to 46,584×. Two of these genomes were obtained from pools of unfed Cx. quinquefasciatus females. Amino acid substitutions found here were not species-specific, which could indicate species specific virus adaptation. In addition, molecular clock dating estimated that ZIKV draft genomes obtained here were co-circulating in the region during the epidemics. Overall results highlight that viral mutations and even minor variants can be detected in genomes directly sequenced from mosquito samples and insights about natural viral genomic variability and viral evolution can be useful when designing tools for mosquito control programs.

Copyright © 2019. Published by Elsevier B.V.

KEYWORDS: Aedes aegypti; Arboviruses; Culex quinquefasciatus; Surveillance; ZIKV

PMID: 31918041 DOI: 10.1016/j.meegid.2020.104180

Keywords: Zika Virus; Aedes aegypti; Culex quinquefascitus; Mosquitoes; Brazil.

——

No #evidence of #Zika, #dengue, or #chikungunya virus #infection in field-caught #mosquitoes from the Recife Metropolitan Region, #Brazil, 2015 (Wellcome Open Res., abstract)

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

Wellcome Open Res. 2019 Jun 10;4:93. doi: 10.12688/wellcomeopenres.15295.1. eCollection 2019.

No evidence of Zika, dengue, or chikungunya virus infection in field-caught mosquitoes from the Recife Metropolitan Region, Brazil, 2015.

Ramesh A#1,2, Jeffries CL#3, Castanha P4,5, Oliveira PAS1, Alexander N2, Cameron M3, Braga C1, Walker T3.

Author information: 1 Department of Parasitology, Instituto Aggeu Magalhães(IAM/FIOCRUZ Pernambuco), Recife, Brazil. 2 Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, WC1E 7HT, UK. 3 Department of Disease Control, London School of Hygiene & Tropical Medicine, London, WC1E 7HT, UK. 4 Department of Virology, Instituto Aggeu Magalhães(IAM/FIOCRUZ Pernambuco), Recife, Brazil. 5 Universidade Estadual de Pernambuco (UPE), Recife, Brazil. #Contributed equally

 

Abstract

Background:

The Recife Metropolitan Region (RMR), north-eastern Brazil, was the epicentre of the 2015 Zika virus (ZIKV) epidemic, which was followed by a 2016 chikungunya virus (CHIKV) epidemic. It historically has amongst the highest incidence of dengue virus (DENV) infections and is the only remaining focus of lymphatic filariasis (LF) in Brazil. In early 2015, a molecular xenomonitoring surveillance project focused on Culex (Cx.) quinquefasciatus commenced to inform LF elimination activities. Aedes (Ae.) aegypti mosquitoes were also collected, concurrent with the first microcephaly cases detected in the RMR. In terms of the 2015 ZIKV epidemic, these are the earliest known field-collected mosquitoes, preserved for potential RNA virus detection, when ZIKV was known to be circulating locally.

Methods:

Adult mosquitoes were collected in two sites (0.4 km 2) of Sítio Novo, Olinda, RMR, from July 22 to August 21, 2015. Mosquitoes were morphologically identified, sorted by physiological status, and pooled (up to 10 mosquitoes per house per day or week). RNA was extracted, reverse transcribed and the cDNA tested by real-time PCR.

Results:

A total of 10,139 adult female Cx. quinquefasciatus and 939 adult female Ae. aegypti were captured. All female Ae. aegypti specimens were included within 156 pools and screened for ZIKV, DENV and CHIKV. In addition, a sub-set of 1,556 Cx. quinquefasciatus adult females in 182 pools were screened for ZIKV. No evidence of infection with any of the three arboviruses was found.

Conclusions:

The absence of arbovirus detection may have been expected given the extremely restricted geographic area and collection of mosquitoes during a very short time period of peak mosquito abundance (July-September), but low arbovirus circulation (November-March).  However, this study demonstrates the potential to retrospectively screen for additional unexpected pathogens in situations of rapid emergence, such as occurred during the outbreak of ZIKV in the RMR.

KEYWORDS: Aedes aegypti; Culex quinquefasciatus; Zika virus; arboviruses; chikungunya virus; dengue virus; disease surveillance; molecular xenomonitoring; neglected tropical diseases; urban areas

PMID: 31363498 PMCID: PMC6644828 DOI: 10.12688/wellcomeopenres.15295.1

Keywords: Arbovirus; Zika virus; Chikungunya fever; Dengue fever; Mosquitoes; Culex quinquefasciatus; Aedes aegypti; Brazil.

——

#Transmission #potential of African, Asian and American #Zika virus #strains by #Aedes aegypti and #Culex quinquefasciatus from #Guadeloupe (French West Indies) (Emerg Microbes Infect., abstract)

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

Emerg Microbes Infect. 2019;8(1):699-706. doi: 10.1080/22221751.2019.1615849.

Transmission potential of African, Asian and American Zika virus strains by Aedes aegypti and Culex quinquefasciatus from Guadeloupe (French West Indies).

Hery L1, Boullis A1, Delannay C1, Vega-Rúa A1.

Author information: 1a Institute Pasteur of Guadeloupe, Laboratory of Vector Control research, Unit Transmission Reservoir and Pathogens Diversity , Les Abymes , France.

 

Abstract

Zika virus (ZIKV) is an arbovirus that has dramatically spread in South America and the Caribbean regions since 2015. The majority of vector incrimination studies available for ZIKV showed that Aedes aegypti mosquitoes are important vectors for this virus. However, several reports suggest that Culex quinquefasciatus mosquitoes may be implicated in ZIKV transmission in certain urban settings. In the present study, we evaluated the vector competence for ZIKV of Cx. quinquefasciatus and Ae. aegypti mosquitoes from Guadeloupe using African, American and Asian strains. The results demonstrated that Cx. quinquefasciatus is refractory to ZIKV infection whatever the strain tested at 7, 14 or 21 days post-infection (dpi), while ZIKV transmission was recorded in Ae. aegypti for all the three strains. The African ZIKV strain was better transmitted by Ae. aegypti (∼ 50% mean transmission efficiency) and with a shorter incubation period (7 dpi) when compared to the Asian and American strains (<14% transmission efficiency; incubation period of 14-21 dpi). Taken together, these results suggest that only Ae. aegypti mosquitoes are involved in urban ZIKV transmission in Guadeloupe and highlight a higher infectiousness of the African ZIKV strain in this mosquito species when compared to the Asian and American ones.

KEYWORDS: Guadeloupe; Zika virus; vector competence

PMID: 31109248 DOI: 10.1080/22221751.2019.1615849

Keywords: Zika Virus; Mosquitoes; Culex quinquefasciatus; Aedes aegypti; Guadeloupe.

——

#Vertical #transmission of #Zika virus in #Culex quinquefasciatus Say and #Aedes aegypti (L.) #mosquitoes (Sci Rep., abstract)

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

Sci Rep. 2019 Mar 27;9(1):5257. doi: 10.1038/s41598-019-41727-8.
Vertical transmission of Zika virus in Culex quinquefasciatus Say and Aedes aegypti (L.) mosquitoes.

Phumee A1,2, Chompoosri J3, Intayot P4, Boonserm R2, Boonyasuppayakorn S5, Buathong R6, Thavara U3, Tawatsin A3, Joyjinda Y1, Wacharapluesadee S1, Siriyasatien P7.

Author information: 1 Thai Red Cross Emerging Infectious Health Science Centre, Neuroscience Center for Research and Development & WHO-CC for Research and Training on Viral Zoonoses King Chulalongkorn Memorial Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand. 2 Vector Biology and Vector Borne Disease Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand. 3 National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand. 4 Medical Science Program, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand. 5 Applied Medical Virology Research Unit, Department of Microbiology, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand. 6 Department of Disease Control, Bureau of Epidemiology, Ministry of Public Health, Nonthaburi, 11000, Thailand. 7 Vector Biology and Vector Borne Disease Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand. padet.s@chula.ac.th.

 

Abstract

Several mosquito species have been described as vectors for the Zika virus (ZIKV), such as those in the Aedes, Anopheles, Mansonia and Culex genera. Our previous survey studies were found the ZIKV RNA positive in both male, female and larvae of Culex quinquefasciatus Say and Aedes aegypti (L.) mosquitoes collected from active ZIKV infected patients’ homes in Thailand. Therefore, the aims of this study were to investigate whether ZIKV could be vertically transmitted in Cx. quinquefasciatus, Ae. aegypti and Ae. albopictus. Laboratory and field colonies of these mosquito species were maintained and artificially fed with ZIKV in human blood. Fully engorged mosquitoes (F0) were selected and reared for the vertical transmission study. The subsequent mosquito generations were fed with human blood without the virus. ZIKV in the mosquitoes was detected by hemi-nested RT-PCR and sequencing. C6/36 cells were used to isolate ZIKV from samples that tested positive by hemi-nested RT-PCR. Moreover, ZIKV was identified by immunocytochemical staining 7 days after infection in several organs of infected F0 females, including the salivary glands, midguts, yoke granules and facet cells of the eye. The localization of the ZIKV antigen was identified by the presence of the specific antibody in the salivary glands, midguts, yoke granules and facet cells. ZIKV was detected in female and male Cx. quinquefasciatus until the F6 and F2 generations, respectively. The isolated virus showed cytopathic effects in C6/36 cells by 5 days postinfection. The results suggested that the vertical transmission of ZIKV occurs in Cx. quinquefasciatus in the laboratory. However, we were able to detect the presence of ZIKV in Ae. aegypti in only the F1 generation in both male and female mosquitoes, and Ae. albopictus mosquitoes were not able to vertically transmit the virus at all. Data obtained from this study could be valuable for developing a better understanding of the role of Cx. quinquefasciatus as a potential vector for ZIKV transmission in Thailand and may be useful in creating more effective mosquito vector control strategies in the future.

PMID: 30918310 DOI: 10.1038/s41598-019-41727-8

Keywords: Zika Virus; Aedes aegypti; Culex quinquefasciatus; Mosquitoes.

——

#Molecular #Epidemiology and Genetic #Diversity of #Zika Virus from Field-Caught #Mosquitoes in Various Regions of #Thailand (Pathogens, abstract)

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

Pathogens. 2019 Mar 6;8(1). pii: E30. doi: 10.3390/pathogens8010030.

Molecular Epidemiology and Genetic Diversity of Zika Virus from Field-Caught Mosquitoes in Various Regions of Thailand.

Phumee A1,2, Buathong R3, Boonserm R4, Intayot P5, Aungsananta N6, Jittmittraphap A7, Joyjinda Y8, Wacharapluesadee S9, Siriyasatien P10.

Author information: 1 Thai Red Cross Emerging Infectious Diseases-Health Science Centre, World Health Organization Collaborating Centre for Research and Training on Viral Zoonoses, Chulalongkorn Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. amphumee@gmail.com. 2 Vector Biology and Vector Borne Disease Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. amphumee@gmail.com. 3 Bureau of Epidemiology, Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand. romebua@hotmail.com. 4 Vector Biology and Vector Borne Disease Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. sky_rung123@hotmail.com. 5 Medical Science Program, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. khunproaw@gmail.com. 6 Public Health Center 22 Wat Pak Bor, Health Department, Bangkok Metropolitan Administration, Bangkok 10250, Thailand. thephonee@gmail.com. 7 Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand. akanitt@hotmail.com. 8 Thai Red Cross Emerging Infectious Diseases-Health Science Centre, World Health Organization Collaborating Centre for Research and Training on Viral Zoonoses, Chulalongkorn Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. yutthana.jjd@gmail.com. 9 Thai Red Cross Emerging Infectious Diseases-Health Science Centre, World Health Organization Collaborating Centre for Research and Training on Viral Zoonoses, Chulalongkorn Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. spwa@hotmail.com. 10 Vector Biology and Vector Borne Disease Research Unit, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. padet.s@chula.ac.th.

 

Abstract

Zika virus (ZIKV) infection is an emerging and re-emerging arbovirus disease that is transmitted to humans through the bite of infected mosquitoes. ZIKV infections were first described in Thailand in 1954 from the sera of indigenous residents and several travelers returning from Thailand in 2014. However, reported cases in Thailand have been increasing since 2015 and 2016, and epidemiological information about the vectors of ZIKV is unclear. We investigated the molecular epidemiology and genetic diversity of ZIKV from mosquitoes collected from different geographic regions experiencing ZIKV outbreaks in Thailand. Polymerase chain reaction was used to amplify the non-structural protein (NS5) gene of ZIKV, which was then sequenced. A total of 1026 mosquito samples (626 females, 367 males, and 33 larvae) were collected from active ZIKV patients’ houses. ZIKV was detected in 79 samples (7.7%), including Aedes aegypti (2.24% female, 1.27% male, and 0.19% larvae), Culex quinquefasciatus (1.85% female, 1.66% male, and 0.29% larvae), and Armigeres subalbatus (0.1% female and 0.1% male), whereas no ZIKV was detected in Aedes albopictus. Phylogenetic analysis of the 79 positive samples were classified into two clades: Those closely related to a previous report in Thailand, and those related to ZIKV found in the Americas. This is the first report of the detection of ZIKV in Ae. aegypti, Cx. quinquefasciatus, and Ar. subalbatus mosquitoes, and genetic variations of ZIKV in the mosquitoes collected from several geographic regions of Thailand were examined. Detection of ZIKV in male and larval mosquitoes suggests that vertical transmission of ZIKV occurred in these mosquito species. This study provides a more in-depth understanding of the patterns and epidemiologic data of ZIKV in Thailand; the data could be used for future development of more effective prevention and control strategies of ZIKV in Thailand.

KEYWORDS: Thailand; Zika virus; genetic diversity; molecular epidemiology; mosquitoes

PMID: 30845707 DOI: 10.3390/pathogens8010030

Keywords: Zika Virus; Moquitoes; Aedes aegypti; Culex quinquefasciatus; Thailand.

——

#Insecticide #resistance genes affect #Culex quinquefasciatus #vector competence for #WNV (Proc Roy Soc B., abstract)

[Source: Proceedings of the Royal Society Biological Sciences, full page: (LINK). Abstract, edited.]

Insecticide resistance genes affect Culex quinquefasciatus vector competence for West Nile virus

Célestine M. Atyame, Haoues Alout, Laurence Mousson, Marie Vazeille, Mawlouth Diallo, Mylène Weill and Anna-Bella Failloux

Published: 16 January 2019 / DOI: https://doi.org/10.1098/rspb.2018.2273

 

Abstract

Insecticide resistance has been reported to impact the interactions between mosquitoes and the pathogens they transmit. However, the effect on vector competence for arboviruses still remained to be investigated. We examined the influence of two insecticide resistance mechanisms on vector competence of the mosquito Culex quinquefasciatus for two arboviruses, Rift Valley Fever virus (RVFV) and West Nile virus (WNV). Three Cx. quinquefasciatus lines sharing a common genetic background were used: two insecticide-resistant lines, one homozygous for amplification of the Ester2locus (SA2), the other homozygous for the acetylcholinesterase ace-1 G119S mutation (SR) and the insecticide-susceptible reference line Slab. Statistical analyses revealed no significant effect of insecticide-resistant mechanisms on vector competence for RVFV. However, both insecticide resistance mechanisms significantly influenced the outcome of WNV infections by increasing the dissemination of WNV in the mosquito body, therefore leading to an increase in transmission efficiency by resistant mosquitoes. These results showed that insecticide resistance mechanisms enhanced vector competence for WNV and may have a significant impact on transmission dynamics of arboviruses. Our findings highlight the importance of understanding the impacts of insecticide resistance on the vectorial capacity parameters to assess the overall consequence on transmission.

Keywords: Arbovirus; Rift Valley Fever virus; West Nile Virus; Mosquitoes; Insecticides; Culex quinquefasciatus.

——

#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.

——

North #American #Culex pipiens and Culex quinquefasciatus are competent #vectors for #Usutu virus (PLoS Negl Trop Dis., abstract)

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

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

North American Culex pipiens and Culex quinquefasciatus are competent vectors for Usutu virus

Christian L. Cook, Yan-Jang S. Huang, Amy C. Lyons, Barry W. Alto, Isik Unlu, Stephen Higgs, Dana L. Vanlandingham

Published: August 17, 2018 / DOI: https://doi.org/10.1371/journal.pntd.0006732 / This is an uncorrected proof.

 

Abstract

Background

Usutu virus (USUV) is a member of the Japanese encephalitis virus (JEV) serocomplex in the Flaviviridae family. Emergence of USUV in Europe has led to disease burdens in birds and created increasing concern for the potential zoonotic transmission to humans. Whilst USUV has not been detected in the New World, the identification of competent vector species in North America is critical in the assessment of the likelihood of its dispersal and establishment of enzootic transmission cycles. The objective of this study was to determine vector competence of potential mosquito vectors in North America for USUV. Three medically important mosquito species were selected for testing because of their involvement in the transmission of West Nile virus and St. Louis encephalitis virus, two related JEV serocomplex flaviviruses in the New World.

Methodology/Principal findings

Oral challenge of Culex pipiens, Culex quinquefasciatus, and Aedes albopictus was performed to determine the susceptibility and vector competence of North American mosquitoes for USUV. Infection status was monitored by the isolation of virus from homogenized mosquito tissues. The disseminated form of infection was demonstrated by the detection of infectious virus in the head, wings, and legs of infected mosquitoes. The presence of viral RNA in saliva of infected Cx. pipiens and Cx. quinquefasciatus indicated that both species are competent for transmission of USUV.

Conclusions/Significance

Results indicate that members of the Cx. pipiens complex are susceptible to USUV and competent for its transmission potential in North America in the event of its introduction. In contrast, Ae. albopictus were highly refractory to USUV infection, suggesting that this species is unlikely to contribute to USUV transmission in North America.

 

Author summary

Usutu virus is an emerging mosquito-borne flavivirus maintained between avian and mosquito species. Although the pathogen has only been detected in Africa and Europe, a growing concern of its dispersal and zoonotic potential warrants the investigation on the vector competence of mosquito species outside the endemic regions for USUV. Identification of species involved in the transmission cycles allows for the formulation of disease control strategies such as vector control. As observed with West Nile virus and Japanese encephalitis virus, the presence of competent vector species is critical for the establishment of enzootic transmission cycles and contributes to the viral maintenance in nature. Despite differences in the genetics and bionomics of Culex pipiens in the Old World, members of the Cx. pipiensspecies in the New World are competent for USUV based on the results of per os challenges performed in this study. Cx. pipiens and Cx. quinquefasciatus are capable of initiating enzootic transmission cycles in the presence of susceptible avian species and should be targeted for vector control in the event of a disease outbreak.

___

Citation: Cook CL, Huang Y-JS, Lyons AC, Alto BW, Unlu I, Higgs S, et al. (2018) North American Culex pipiens and Culex quinquefasciatus are competent vectors for Usutu virus. PLoS Negl Trop Dis 12(8): e0006732. https://doi.org/10.1371/journal.pntd.0006732

Editor: Eric Mossel, Center for Disease Control and Prevention, UNITED STATES

Received: April 9, 2018; Accepted: August 3, 2018; Published: August 17, 2018

Copyright: © 2018 Cook 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 relevant data are within the paper.

Funding: This project is the result of funding provided by United States Department of Homeland Security Science and Technology Directorate’s Homeland Security Advanced Research Projects Agency Chemical and Biological Defense Division under contract number D15PC00276. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

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

Keywords: Usutu Virus; Mosquitoes; American Region; Culex pipiens; Culex quinquefasciatus; Aedes albopictus.

——-

#Spondweni Virus in Field-Caught #Culex quinquefasciatus #Mosquitoes, #Haiti, 2016 (Emerg Infect Dis., abstract)

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

Volume 24, Number 9—September 2018 / Research Letter

Spondweni Virus in Field-Caught Culex quinquefasciatus Mosquitoes, Haiti, 2016

Sarah K. White1  , John A. Lednicky, Bernard A. Okech, J. Glenn Morris, and James C. Dunford

Author affiliations: University of Florida, Gainesville, Florida, USA (S.K. White, J.A. Lednicky, B.A. Okech, J.G. Morris, Jr.); US Navy and Marine Corps Public Health Center, Portsmouth, Virginia, USA (J.C. Dunford)

 

Abstract

Spondweni virus (SPONV) and Zika virus cause similar diseases in humans. We detected SPONV outside of Africa from a pool of Culex mosquitoes collected in Haiti in 2016. This finding raises questions about the role of SPONV as a human pathogen in Haiti and other Caribbean countries.

Keywords: Spondweni virus; Culex quinquefasciatus; Mosquitoes; Haiti.

——

#Vector competence of #Aedes aegypti, #Culex tarsalis, and Culex quinquefasciatus from #California for #Zika virus (PLoS Negl Trop Dis., abstract)

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

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Vector competence of Aedes aegypti, Culex tarsalis, and Culex quinquefasciatus from California for Zika virus

Bradley J. Main, Jay Nicholson, Olivia C. Winokur, Cody Steiner, Kasen K. Riemersma, Jackson Stuart, Ryan Takeshita, Michelle Krasnec, Christopher M. Barker, Lark L. Coffey

Published: June 21, 2018 / DOI: https://doi.org/10.1371/journal.pntd.0006524

 

Abstract

Zika virus (ZIKV) has emerged since 2013 as a significant global human health threat following outbreaks in the Pacific Islands and rapid spread throughout South and Central America. Severe congenital and neurological sequelae have been linked to ZIKV infections. Assessing the ability of common mosquito species to transmit ZIKV and characterizing variation in mosquito transmission of different ZIKV strains is important for estimating regional outbreak potential and for prioritizing local mosquito control strategies for Aedes and Culex species. In this study, we evaluated the laboratory vector competence of Aedes aegypti, Culex quinquefasciatus, and Culex tarsalis that originated in areas of California where ZIKV cases in travelers since 2015 were frequent. We compared infection, dissemination, and transmission rates by measuring ZIKV RNA levels in cohorts of mosquitoes that ingested blood meals from type I interferon-deficient mice infected with either a Puerto Rican ZIKV strain from 2015 (PR15), a Brazilian ZIKV strain from 2015 (BR15), or an ancestral Asian-lineage Malaysian ZIKV strain from 1966 (MA66). With PR15, Cx. quinquefasciatus was refractory to infection (0%, N = 42) and Cx. tarsalis was infected at 4% (N = 46). No ZIKV RNA was detected in saliva from either Culex species 14 or 21 days post feeding (dpf). In contrast, Ae. aegypti developed infection rates of 85% (PR15; N = 46), 90% (BR15; N = 20), and 81% (MA66; N = 85) 14 or 15 dpf. Although MA66-infected Ae. aegypti showed higher levels of ZIKV RNA in mosquito bodies and legs, transmission rates were not significantly different across virus strains (P = 0.13, Fisher’s exact test). To confirm infectivity and measure the transmitted ZIKV dose, we enumerated infectious ZIKV in Ae. aegypti saliva using Vero cell plaque assays. The expectorated plaque forming units PFU varied by viral strain: MA66-infected expectorated 13±4 PFU (mean±SE, N = 13) compared to 29±6 PFU for PR15-infected (N = 13) and 35±8 PFU for BR15-infected (N = 6; ANOVA, df = 2, F = 3.8, P = 0.035). These laboratory vector competence results support an emerging consensus that Cx. tarsalis and Cx. quinquefasciatus are not vectors of ZIKV. These results also indicate that Ae. aegypti from California are efficient laboratory vectors of ancestral and contemporary Asian lineage ZIKV.

 

Author summary

Assessing the ability of common mosquito species to transmit Zika virus (ZIKV) and characterizing variation in mosquito transmission of different ZIKV strains is important for estimating regional outbreak potential and for prioritizing local mosquito control strategies for Aedes and Culex species. In this study, we evaluated the laboratory vector competence of Aedes aegypti, Culex quinquefasciatus, and Culex tarsalis that originated in areas of California where ZIKV cases in travelers since 2015 were frequent. We observed variation in infection loads between ZIKV strains in Ae. aegypti, but transmission rates were not different. In addition, there was a positive relationship between ZIKV RNA levels in infected mosquitoes ascertained from bodies and ZIKV RNA transmission rates. Our data add to the growing body of evidence supporting the role of Aedes aegypti as a ZIKV vector and refute Cx. quinquefasciatus and Cx. tarsalis as vectors.

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Citation: Main BJ, Nicholson J, Winokur OC, Steiner C, Riemersma KK, Stuart J, et al. (2018) Vector competence of Aedes aegypti, Culex tarsalis, and Culex quinquefasciatusfrom California for Zika virus. PLoS Negl Trop Dis 12(6): e0006524. https://doi.org/10.1371/journal.pntd.0006524

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

Received: March 19, 2018; Accepted: May 11, 2018; Published: June 21, 2018

Copyright: © 2018 Main 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 relevant data are within the paper.

Funding: Primary funding for this work was provided by Abt Associates and a consortium of vector control districts in California: Coachella Valley, Orange County, Greater Los Angeles County, San Gabriel Valley, West Valley, Kern, Butte County, Tulare, Sacramento-Yolo, Placer, and Turlock. OCW and CMB also acknowledge financial support from NASA Health and Air Quality grant NNX15AF36G, and CMB and LLC acknowledge funding support from the Pacific Southwest Regional Center of Excellence for Vector-Borne Diseases funded by the U.S. Centers for Disease Control and Prevention (Cooperative Agreement 1U01CK000516). KKR was supported by a National Institutes of Health Ruth L. Kirschstein National Research Service Award T32 OD O11147. Part of this work was supported by start-up funds provided to LLC by the Pathology, Microbiology and Immunology Department in the School of Veterinary Medicine at UC Davis. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. One funder, Abt Associates, provided support in the form of salaries for authors [MK and RT], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.

Competing interests: Michelle Krasnec and Ryan Takeshita are/were employed by Abt Associates. Abt Associates provided support in the form of salaries for authors [MK and RT], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.

Keywords: Zika Virus; Mosquitoes; USA; California; Aedes aegypti; Culex quinquefasciatus; Culex tarsalis.

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