Transmission of Major Arboviruses in Brazil: The Role of Aedes aegypti and Aedes albopictus Vectors

AbstractInsecticide resistant Aedes populations have recently been reported in Pakistan, imposing a threat to their control. We aimed to evaluate the susceptibility of Aedes aegypti and Aedes albopictus populations from Lahore to WHO-recommended insecticides and to investigate metabolic and target-site resistance mechanisms. For this purpose, we first carried out bioassays with the larvicides temephos and pyriproxyfen, and the adulticides malathion, permethrin, deltamethrin, alpha-cypermethrin, and etofenprox. We looked for Knockdown resistance mutations (kdr) by qPCR, High-Resolution Melt (HRM), and sequencing. In order to explore the role of detoxifying enzymes in resistance, we carried out synergist bioassay with both species and then checked the expression of CYP9M6, CYP9J10, CYP9J28, CYP6BB2, CCAe3a, and SAP2 genes in Ae. aegypti. Both species were susceptible to organophosphates and the insect growth regulator, however resistant to all pyrethroids. We are reporting the kdr haplotypes 1520Ile + 1534Cys and T1520 + 1534Cys in high frequencies in Ae. aegypti while Ae. albopictus only exhibited the alteration L882M. PBO increased the sensitivity to permethrin in Ae. aegypti, suggesting the participation of P450 genes in conferring resistance, and indeed, CYP928 was highly expressed. We presume that dengue vectors in Lahore city are resistant to pyrethroids, probably due to multiple mechanisms, such as kdr mutations and P450 overexpression.

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Surveillance of Zika virus in field-caught Aedes aegypti and Aedes albopictus suggests important role of male mosquitoes in viral populations maintenance in Medellín, Colombia

Infection Genetics and Evolution ◽

10.1016/j.meegid.2020.104434 ◽

2020 ◽

Vol 85 ◽

pp. 104434

Author(s):

Arley Calle-Tobón ◽

Juliana Pérez-Pérez ◽

Raul Rojo ◽

Winston Rojas-Montoya ◽

Omar Triana-Chavez ◽

...

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Zika Virus ◽

Male Mosquitoes

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Penentuan Status Maya Index Larva Aedes Sp.

Jurnal Penelitian Perawat Profesional ◽

10.37287/jppp.v2i1.40 ◽

2020 ◽

Vol 2 (1) ◽

pp. 15-24

Author(s):

Fatimah Azzahra ◽

Emantis Rosa ◽

Muhammad Galih Irianto ◽

Hanna Mutiara

Keyword(s):

Aedes Aegypti ◽

Dengue Fever ◽

Aedes Albopictus ◽

Risk Index ◽

Water Reservoir ◽

Breeding Site ◽

The Status ◽

Mosquito Breeding ◽

Breeding Place

Demam berdarah atau DBD adalah penyakit yang ditularkan melalui vektor nyamuk Aedes aegypti dan Aedes albopictus. Maya Index dapat digunakan untukmengidentifikasi suatu area yang memiliki risiko tinggi sebagai tempat perkembangbiakan atau breeding site nyamuk Aedes sp. didasarkan pada status kebersihan lingkungan dan ketersediaan tempat–tempat yang berpotensi sebagai tempat perkembangbiakan nyamuk. Tujuan penelitian ini adalah untuk mengetahui status Maya Index, mengidentifikasi tipe tempat penampungan air atau TPA, dan mengidentifikasi jenis larva Aedes sp. yang ditemukandi kecamatan Sukabumi yang dilakukan pada bulan November-Desember 2019. Penelitian ini dilakukan dengan cara survey ke 100 rumah masyarakat di 3 kelurahan, yaitu kelurahan Nusantara, kelurahan Sukabumi dan Kelurahan Sukabumi Indah. Analisis Maya Index menggunakan Breeding Risk Index atau BRI and Hygiene Risk Indexatau HRI. Hasil dari penelitian ini menunjukkan bahwa TPA terkontrol yang paling berpotensi untuk perkembangbiakan nyamuk adalah tempat penampungan air pada dispenser, sedangan TPA tidak terkontrol yang paling berpotensi untuk perkembangbiakan nyamuk adalah kaleng bekas. Ada 2 tipe dari larva nyamuk yang ditemukan, yaitu Aedes aegypti dengan persentase 73.5% dan Aedes albopictus dengan persentase 26.5%. Status Maya Index dikategorikan kepada kategori sedang yang ditentukan bedasarkan kategoriBreeding Risk Index dan Hygiene risk index. Namun demikian, hal itu tidak berarti daerah tersebut bebas dari kasus DBD. Pengaturan dari masyarakat sangat dibutuhkan untuk mengeradikasi TPA yang memiliki potensial tinggi sebagai tempat perkembangbiakan vektor DBD. Kata Kunci: demam berdarah, larva aedes sp., maya index DETERMINATION THE MAYA INDEX STATUS OF AEDES SP. LARVAE ABSTRACT Dengue Fever is a disease that is transmitted through the Aedes aegypti and Aedes albopictus mosquito vectors. Maya Index can be used to identify an area that has a high risk of breeding site of the Aedes sp. Mosquito based on the status of environmental hygiene and the availability of potential places of mosquito breeding. The aim of this study was to determine the type of landfill which has the potential as a breeding ground for mosquitoes, to find out the larvae found in various landfill sites, and to know the Maya index status in Sukabumi District which was carried out in November-December 2019. This research conducted by a direct survey of 100 houses in 3 villages in Sukabumi District, namely Nusantara, Sekabumi, and Sukabumi Indah. Data analysis to determine Maya Index uses the Breeding Risk Index or BRI and Hygiene risk index or HRI. The results indicated that the type of controlled water reservoir that had the most potential as a breeding place for mosquitoes was a water reservoir of dispenser, while the type of water reservoir that was not controlled which had the potential as a place for mosquito breeding was a used cans. There were 2 types of larvae found, namely, Aedes aegypti larvae with a percentage of 73.5% and Aedes albopictus larvae with a percentage of 26.5%. The Maya index status detected there, was a medium category, which obtained from the Breeding Risk Index category and Hygiene Risk Index category. Besides, it did not mean that the area has been free from dengue cases. The role of the community is still very much needed in eradicating landfills which has the potential as a breeding place for dengue mosquitoes vector. Keyword: dengue fever, larva of aedes sp., maya index

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Distribution of Aedes aegypti and Aedes albopictus in different eco zones of Thiruvananthapuram city with special reference to dengue viremia in humans

ENTOMON ◽

10.33307/entomon.v43i4.402 ◽

2018 ◽

Vol 43 (4) ◽

pp. 223-230

Author(s):

S. Sunil Kumar ◽

D.A. Evans ◽

K. Muthulakshmi ◽

T. DilipKumar ◽

R. Heera Pillai ◽

...

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Dengue Shock Syndrome ◽

Single Step ◽

Equal Distribution ◽

Distribution Study ◽

Urban Zone ◽

High Prevalence ◽

Vector Management ◽

Efficient Vector

Mosquito index study of three ecologically different ecozones of the Thiruvananthapuram district, Kerala showed sharp difference on the proportionate distribution of Aedes aegypti and Aedes albopictus. Human dengue viremia (HDV) was very high in those ecozones where A.aegypti density was high and HDV was low where A.albopictus was high. In a coastal zone of Thiruvananthapuram city, A. aegypti was the most abundant vector and in a hilly, arid suburban zone, A.albopictus was the abundant vector. In the urban zone both species of mosquitoes showed equal distribution. Study on the circulating serotypes in the serum of HDV by Single step single tube Multiplex PCR showed all the four serotypes viz DENV1, DENV2, DENV3 and DENV4 in patients of Thiruvananthapuram city, which indicated the possibility of Dengue Shock Syndrome, unless there is efficient vector management. Among the four dengue serotypes, Type 1 was the most abundant virus. Abundance of microhabitats in Thiruvananthapuram city, which support A. aegypti may be the reason for high prevalence of dengue fever in the urban zone.

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Insecticide Susceptibility Status of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in Awka South Local Government Area, Anambra State, Nigeria

10.35248/2161-0983.19.8.220 ◽

2019 ◽

Vol 8 (3) ◽

Author(s):

Nwankwo EN ◽

Ononye IP ◽

Ogbonna CU ◽

Ezihe EK ◽

Onwude CO ◽

...

Keyword(s):

Local Government ◽

Aedes Aegypti ◽

Aedes Albopictus ◽

Local Government Area ◽

Insecticide Susceptibility ◽

Anambra State ◽

Susceptibility Status

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A Simple PCR Assay for Discrimination of Dengue Vectors from Nsukka LGA, Nigeria

International Annals of Science ◽

10.21467/ias.10.1.67-77 ◽

2020 ◽

Vol 10 (1) ◽

pp. 67-77

Author(s):

Amos Watentena ◽

Ikem Chris Okoye ◽

Ikechukwu Eugene Onah ◽

Onwude Cosmas Ogbonnaya ◽

Emmanuel Ogudu

Keyword(s):

Aedes Aegypti ◽

Aedes Albopictus ◽

Mosquito Species ◽

Public Health Problem ◽

Major Public Health Problem ◽

Mosquito Vector ◽

Aedes Mosquitoes ◽

Allele Specific ◽

Arboviral Diseases ◽

Dengue Vectors

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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