Analysis in a murine model points to IgG responses against the 34k2 salivary proteins from Aedes albopictus and Aedes aegypti as novel promising candidate markers of host exposure to Aedes mosquitoes

Mosquitoes of Aedes species are vectors of several arboviral diseases which continue to be a major public health problem in Nigeria. This study among other things, morphologically identified Aedes mosquitoes collected from Nsukka LGA and used an allele specific PCR amplification for discrimination of dengue vectors. Larval sampling, BG-sentinel traps and modified human landing catches were used for mosquito sampling in two selected autonomous communities of Nsukka LGA (Nsukka and Obimo). A total of 124 Aedes mosquitoes consisting of five (5) different species were collected from April to June, 2019 in a cross-sectional study that covered 126 households, under 76 distinct geographical coordinates. Larvae was mainly collected from plastic containers 73% (n=224), metallic containers 14% (n=43), earthen pots 9% (n=29) and used car tyres 3% (n=9), reared to adult stage 69.35% (n=86), and all mosquitoes were identified using standard morphological keys. Five (5) Aedes mosquito species were captured; Aedes aegypti 83(66.94%), Aedes albopictus 33(26.61%), Aedes simpsoni (4.48%), Aedes luteocephalus (≤1%) and Aedes vittatus (≤1%). Nsukka autonomous community had higher species diversity than Obimo. Allele specific amplification confirmed dengue vectors, Aedes aegypti and Aedes albopictus species on a 2% agarose gel. Since the most recent re-emergence of arboviral diseases is closely associated with Aedes species, findings of this study, therefore, give further evidence about the presence of potential arboviral vectors in Nigeria and describe the role of a simple PCR in discriminating some. Further entomological studies should integrate PCR assays in mosquito vector surveillance.

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Key breeding sites of Aedes mosquitoes in Huaylau village, Pakse city, Champasack province, Lao People Democratic Republic 2019

Journal of Health and Development Studies ◽

10.38148/jhds.0502skpt20-080 ◽

2021 ◽

Vol 05 (02) ◽

pp. 52-61

Author(s):

Thi Thanh Huong Le ◽

◽

Quynh Nguyen ◽

Saenthavisouk Vanhnasack ◽

Sinh Nam Vu

Keyword(s):

Aedes Aegypti ◽

Dengue Fever ◽

Aedes Albopictus ◽

Statistical Significance ◽

P Value ◽

Epidemic Threshold ◽

Cross Sectional ◽

Breeding Sites ◽

Aedes Mosquitoes ◽

The Village

Objectives: The elimination of key breeding sites of dengue vector is applied worldwide to control the vector density under the critical epidemic threshold. This study aimed to identify key breeding sites of Aedes mosquitos and associated factors in Huaylau village, Pakse city, Champasack province in Laos in 2019. Methods: This was a cross-sectional study, combining of immature stage survey of Aedes mosquitoes in all water and discarded containers and the community’s knowledge and practices on the prevention of dengue fever in all 240 households in Huaylau village. Multivariate logistic regression was applied to identify factors associated with the absence of Aedes larvae and pupae in the village. Statistical significance was set at a p-value less than 0.05. Results: Among the 720 water and discarded containers surveyed, the study found 654 Aedes larvae and pupae; of which 94.6% were immature Aedes aegypti. Key breeding sites of Aedes aegypti included water jars (34.2%), plastic drums (30.7%), tanks < 500 litter (14.7%), and discarded containers (12.6%), while that of all Aedes albopictus was discarded containers. The community’s better practices on the prevention of dengue fever contributed to the increased odds of the absence of Aedes larvae ad pupae by 1.612 (95%CI: 1.218-2.134, p<0.01), and the cleanliness of the house were associated with the increased odds of 4.072 of the absent Aedes larvae and pupae in the participated households (95%CI: 1.589-10.434, p<0.01). Conclusions: Aedes aegypti mosquitoes in the Huaylau village laid their eggs in various breeding sites, including water containers and discarded containers while discarded containers were the only key breeding site of Aedes albopictus. Better practices on dengue prevention and better hygiene conditions of the houses contributed to the absence of Aedes larvae and pupae. Special attention should be paid to the clearance of all discarded containers and education of the community people to cover water containers in the village. Keywords: key breeding sites, Aedes, mosquito, pupae, larvae, Champasack province, Lao PDR

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Insect-specific viruses regulate vector competence in Aedes aegypti mosquitoes via expression of histone H4

10.1101/2021.06.05.447047 ◽

2021 ◽

Author(s):

Roenick P. Olmo ◽

Yaovi Mathias H. Todjro ◽

Eric R. G. R. Aguiar ◽

Joao Paulo P. de Almeida ◽

Juliana N. Armache ◽

...

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Molecular Basis ◽

Vector Competence ◽

Spatiotemporal Analysis ◽

Host Factor ◽

Mosquito Vectors ◽

Histone H4 ◽

African Cities ◽

Aedes Mosquitoes

Aedes aegypti and Aedes albopictus are major mosquito vectors for arthropod-borne viruses (arboviruses) such as dengue (DENV) and Zika (ZIKV) viruses. Mosquitoes also carry insect-specific viruses (ISVs) that may affect the transmission of arboviruses. Here, we analyzed the global virome in urban Aedes mosquitoes and observed that two insect-specific viruses, Phasi Charoen-like virus (PCLV) and Humaita Tubiacanga virus (HTV), were the most prevalent in A. aegypti worldwide except for African cities, where transmission of arboviruses is low. Spatiotemporal analysis revealed that presence of HTV and PCLV led to a 200% increase in the chances of having DENV in wild mosquitoes. In the laboratory, we showed that HTV and PCLV prevented downregulation of histone H4, a previously unrecognized proviral host factor, and rendered mosquitoes more susceptible to DENV and ZIKV. Altogether, our data reveals a molecular basis for the regulation of A. aegypti vector competence by highly prevalent ISVs that may impact how we analyze the risk of arbovirus outbreaks.

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TRUCK-MOUNTED NATULAR 2EC (SPINOSAD) ULV RESIDUAL TREATMENT IN A SIMULATED URBAN ENVIRONMENT TO CONTROL AEDES AEGYPTI AND AEDES ALBOPICTUS IN NORTH FLORIDA

Journal of the American Mosquito Control Association ◽

10.2987/17-6697r.1 ◽

2018 ◽

Vol 34 (1) ◽

pp. 53-57 ◽

Cited By ~ 4

Author(s):

Robert L. Aldridge ◽

Frances V. Golden ◽

Seth C. Britch ◽

Jessika Blersch ◽

Kenneth J. Linthicum

Keyword(s):

Aedes Aegypti ◽

Urban Environment ◽

Aedes Albopictus ◽

Management Program ◽

Urban Setting ◽

Integrated Vector Management ◽

Aedes Mosquitoes ◽

Vector Management ◽

Low Volume ◽

Treatment Application

ABSTRACT Preemptive treatment of dry habitats with an ultra-low volume (ULV) residual larvicide may be effective in an integrated vector management program to control populations of container-inhabiting Aedes mosquitoes, key vectors of Zika, dengue, and chikungunya viruses. We exposed dry, artificial containers placed in exposed and protected locations to Natular 2EC (spinosad) larvicide applied with a truck-mounted ULV sprayer in a simulated urban setting in North Florida, and later introduced water and Ae. aegypti or Ae. albopictus larvae to conduct bioassays. Up to 50% mortality was observed in bioassays, indicating further analysis of spinosad as a residual treatment application.

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Analyses of Insecticide Resistance Genes in Aedes aegypti and Aedes albopictus Mosquito Populations from Cameroon

Genes ◽

10.3390/genes12060828 ◽

2021 ◽

Vol 12 (6) ◽

pp. 828

Author(s):

Borel Djiappi-Tchamen ◽

Mariette Stella Nana-Ndjangwo ◽

Konstantinos Mavridis ◽

Abdou Talipouo ◽

Elysée Nchoutpouen ◽

...

Keyword(s):

Aedes Aegypti ◽

Insecticide Resistance ◽

Aedes Albopictus ◽

Expression Profiles ◽

Resistance Mechanisms ◽

Vector Borne Diseases ◽

Aedes Mosquitoes ◽

Control And Prevention ◽

Vector Borne ◽

First Time

The emergence of insecticide resistance in Aedes mosquitoes could pose major challenges for arboviral-borne disease control. In this paper, insecticide susceptibility level and resistance mechanisms were assessed in Aedes aegypti (Linnaeus, 1762) and Aedes albopictus (Skuse, 1894) from urban settings of Cameroon. The F1 progeny of Aedes aegypti and Aedes albopictus collected in Douala, Yaoundé and Dschang from August to December 2020 was tested using WHO tube assays with four insecticides: deltamethrin 0.05%, permethrin 0.75%, DDT 4% and bendiocarb 0.1%. TaqMan, qPCR and RT-qPCR assays were used to detect kdr mutations and the expression profiles of eight detoxification genes. Aedes aegypti mosquitoes from Douala were found to be resistant to DDT, permethrin and deltamethrin. Three kdr mutations, F1534C, V1016G and V1016I were detected in Aedes aegypti populations from Douala and Dschang. The kdr allele F1534C was predominant (90%) in Aedes aegypti and was detected for the first time in Aedes albopictus (2.08%). P450s genes, Cyp9J28 (2.23–7.03 folds), Cyp9M6 (1.49–2.59 folds), Cyp9J32 (1.29–3.75 folds) and GSTD4 (1.34–55.3 folds) were found overexpressed in the Douala and Yaoundé Aedes aegypti populations. The emergence of insecticide resistance in Aedes aegypti and Aedes albopictus calls for alternative strategies towards the control and prevention of arboviral vector-borne diseases in Cameroon.

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First detection of dengue and chikungunya viruses in natural populations of Aedes aegypti in Martinique during the 2013 – 2015 concomitant outbreak

Revista Panamericana de Salud Pública ◽

10.26633/rpsp.2017.63 ◽

2017 ◽

Vol 41 ◽

pp. 1 ◽

Cited By ~ 5

Author(s):

Laurence Farraudière ◽

Fabrice Sonor ◽

Said Crico ◽

Manuel Étienne ◽

Laurence Mousson ◽

...

Keyword(s):

Public Health ◽

Aedes Aegypti ◽

Aedes Albopictus ◽

West Indies ◽

Natural Populations ◽

French West Indies ◽

Aedes Mosquitoes ◽

Health Authorities ◽

Public Health Authorities ◽

First Time

Dengue and chikungunya viruses are transmitted by Aedes mosquitoes. In Martinique, an island of the French West Indies, Aedes aegypti is the suspected vector of both arboviruses; there is no Aedes albopictus on the island. During the concomitant outbreak of 2013 – 2015, the authors collected wild A. aegypti populations, and for the first time, detected dengue and chikungunya viruses in field-collected females. This paper demonstrates the mosquito’s role in transmission of both dengue and chikungunya on the island, and also highlights a tool that public health authorities can use for preventing outbreaks.

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Variation in the susceptibility of urban Aedes mosquitoes infected with a densovirus

Scientific Reports ◽

10.1038/s41598-020-75765-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Aurélie Perrin ◽

Anne-Sophie Gosselin-Grenet ◽

Marie Rossignol ◽

Carole Ginibre ◽

Bethsabée Scheid ◽

...

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Mortality Rates ◽

Biocontrol Agents ◽

Environmental Toxicity ◽

Aedes Mosquitoes ◽

Specific Variation ◽

Different Strains ◽

Entomopathogenic Viruses ◽

Alternative Control Methods

Abstract Urban Aedes mosquitoes are vectors of many viruses affecting human health such as dengue, chikungunya and Zika viruses. Insecticide resistance and environmental toxicity risks hamper the effectiveness of chemical control against these mosquito vectors. Alternative control methods, such as the use of mosquito-specific entomopathogenic viruses should be explored. Numerous studies have focused on evaluating the potential of different densoviruses species as biological control agents. However, knowledge on the extent of inter- and intra-specific variations in the susceptibility of Aedes mosquitoes to infection by different densoviruses remains insufficient. In this study, we compared infection and mortality rates induced by the Aedes albopictus densovirus 2 in different strains of Aedes albopictus and Aedes aegypti mosquitoes. The two Aedes species were different in terms of susceptibility to viral infection. Under laboratory conditions, Aedes albopictus densovirus 2 appeared more virulent for the different strains of Aedes aegypti tested than for those of Aedes albopictus. In addition, we also found significant intra-specific variation in infection and mortality rates. Thus, although even if Aedes albopictus densoviruses could be powerful biocontrol agents used in the management of urban Aedes populations, our results also call into question the use of single viral isolate as biocontrol agents.

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Comparative Skip-Oviposition Behavior Among Container Breeding Aedes spp. Mosquitoes (Diptera: Culicidae)

Journal of Medical Entomology ◽

10.1093/jme/tjab084 ◽

2021 ◽

Author(s):

Drew David Reinbold-Wasson ◽

Michael Hay Reiskind

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Egg Production ◽

Tap Water ◽

Oviposition Behavior ◽

Site Conditions ◽

Gonotrophic Cycle ◽

Spreading Behavior ◽

Aedes Mosquitoes ◽

Oviposition Sites

Abstract Container Aedes mosquitoes are the most important vectors of human arboviruses (i.e., dengue, chikungunya, Zika, or yellow fever). Invasive and native container Aedes spp. potentially utilize natural and artificial containers in specific environments for oviposition. Several container Aedes spp. display ‘skip-oviposition’ behavior, which describes the distribution of eggs among multiple containers during a single gonotrophic cycle. In this study, we compared individual skip-oviposition behavior using identical eight-cup testing arenas with three container Aedes species: Aedes aegypti (Linnaeus), Aedes albopictus (Skuse), and Aedes triseriatus (Say). We applied the index of dispersion, an aggregation statistic, to individual mosquitoes’ oviposition patterns to assess skip-oviposition behavior. Aedes aegypti and Ae. albopictus utilized more cups and distributed eggs more evenly among cups than Ae. triseriatus under nutritionally enriched oviposition media (oak leaf infusion) conditions. When presented with a nutritionally unenriched (tap water) oviposition media, both Ae. aegypti and Ae. albopictus increased egg spreading behavior. Aedes albopictus did not modify skip-oviposition behavior when reared and assessed under fall-like environmental conditions, which induce diapause egg production. This study indicates specific oviposition site conditions influence skip-oviposition behavior with ‘preferred’ sites receiving higher amounts of eggs from any given individual and ‘non-preferred’ sites receive a limited contribution of eggs. A further understanding of skip-oviposition behavior is needed to make the best use of autodissemination trap technology in which skip-ovipositing females spread a potent larvicide among oviposition sites within the environment.

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Attraction of the Mosquitoes Aedes aegypti and Aedes albopictus (Diptera: Culicidae) to a 3-Part Phytochemical Blend in a Mesocosm

Journal of Medical Entomology ◽

10.1093/jme/tjab195 ◽

2021 ◽

Author(s):

Robert P Hutcheson ◽

Babak Ebrahimi ◽

Basilio N Njiru ◽

Woodbridge A Foster ◽

William Jany

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Mosquito Species ◽

Population Surveillance ◽

Anopheline Mosquito ◽

Blend Ratio ◽

Aedes Mosquitoes ◽

And Control ◽

Trap Catches ◽

Ratio Of Components

Abstract Aedes aegypti (L.) and Aedes albopictus (Skuse) mosquitoes of both sexes were attracted to a 3-part volatile synthetic phytochemical blend but differed according to their component ratios, 7:3:2 or 1:1:1, and their initial concentrations. These arbovirus vectors were presented with the blends as baits in paired baited and blank CFG traps in a large greenhouse mesocosm. Ae. aegypti attraction was highest at a 7:3:2 blend ratio, but at a concentration half that found most effective for an anopheline mosquito species in outdoor screenhouses. Both lower and higher concentrations yielded substantially lower attraction scores for Ae. aegypti. By contrast, the few tests conducted on Ae. albopictus showed that it was not as sensitive to concentration, but again it was more responsive to the 7:3:2 ratio of components than to the 1:1:1 ratio. The two sexes of both species were represented equally in the trap catches, indicating the potential value of this and similar attractive blends for population surveillance and control of Aedes mosquitoes.

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Detection of dengue virus in Aedes mosquitoes in Delhi, India

ENTOMON ◽

10.33307/entomon.v44i3.466 ◽

2019 ◽

Vol 44 (3) ◽

pp. 213-218

Author(s):

Suresh Chand Kaushik ◽

Sukhvir Singh ◽

Purnima Srivastava ◽

R. Rajendran

Keyword(s):

Early Intervention ◽

Early Detection ◽

Aedes Aegypti ◽

Dengue Virus ◽

Infection Rate ◽

Transmission Season ◽

Aedes Mosquitoes ◽

Alternative Approach ◽

Human Sera ◽

Minimum Infection Rate

Detection of viruses in human sera particularly in endemic areas is cumbersome and laborious. Therefore, an alternative approach, Immuno-fluorescence assay (IFA) was performed to determine dengue virus (DENV) positivity in mosquitoes. A total of 1055 adult Aedes aegypti female mosquitoes were tested for IFA test against DENV. Minimum infection rate (MIR) for DENV was found higher during August to November 2016 ranging from 10.75 to 20.83. The average yearly MIR was about 6.64. Higher MIR for Ae. aegypti was found in Sarfabad, Noida (12.71) and Khoda Colony, Ghaziabad (11.90). Minimum MIR (4.67) was observed in Sanjay colony (Faridabad). The main contribution of this study resides in the development of a more suitable monitoring system for early detection of viral circulation and to prioritize early intervention in the non-transmission season.

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