Nghiên cứu phân bố, tập tính, độ nhạy cảm với hóa chất diệt côn trùng của muỗi aedes aegypti và aedes albopictus tại tỉnh bình định và gia lai (2016 2018) tt tiếng anh

MINISTRY OF HEALTH
THE SOCIALIST REPUPLIC OF VIETNAM
NATIONAL INSTITUTE OF
Independence – Freedom – Happiness
MALARIOLOGY-PARASITOLOGY
---------------------------AND ENTOMOLOGY
----------------Ph.D THESIS SUMMARY SUBMITTING TO THE WEBSITE OF
THE MINISTRY OF EDUCATION AND TRAINING
Thesis title: “Studies on distribution, behaviour and insecticide susceptibility status of Aedes
aegypti and Aedes albopictus in Binh Dinh and Gia Lai provinces (2016-2018)”
The objectives of the study are:
1. Determination of the distribution, behaviour and prevalence of Dengue virus in Aedes aegypti
and Aedes albopictus at study sites in Binh Dinh and Gia Lai provinces (2016-2018).
2. Evaluation of the susceptibility to some insecticides and kdr gene mutation of Aedes aegypti and
Aedes albopictus in study sites.
Major: Entomology;
Code: 62.72.01.16
Ph.D Student: Do Van Nguyen
Promotors:1. Dr. Nguyen Xuan Quang 2. Dr. Huỳnh Hồng Quang.
Training institution: National Institute of Malariology, Parasitology and Entomology (NIMPE)
Main findings of the thesis:
1. Distribution, behaviour and Dengue virus infection rate of Aedes aegypti and Aedes albopictus at study
sites in Binh Dinh and Gia Lai provinces (2016-2018).
1.1. Distribution and Dengue vector indices
Aedes aegypti and Aedes albopictus populations were found in all landscapes of Binh Dinh and Gia Lai
provinces, except mountainous landscapes where Aedes albopictus was not found.
Binh Dinh province: Aedes aegypti and Aedes albopictus accounted for 97.1% and 2.9% respectively.
The highest density index of Ae. aegypti was recorded in urban areas (0.9 mos/house), flatlands (0.83
mos/house) in 10/2016, in mountainous areas in 10/2016 (0.7 mos/house). Similarly, in urban areas the
BI index was the highest in 10/2017, in flatlands and mountainous area the highest BI index was recorded
in 10/2016 (BI: 56); In Gia Lai province, Aedes aegypti and Aedes albopictus accounted for 88.1% and

11.9% respectively. The DI index of ae aegypti was the highest in urban areas in 8/2017 (0.6 mos/house),
rural areas 1 in 10/2016 (0.7 mos/house), rural areas 2 in 6/2016 and 8/2017 (0.45 mos/house). BI of Ae.
aegypti was highest in urban areas in 10/2017 (74), rural areas 1 in 12/2016 (92) and rural areas 2 in
12/2016 (77).
1.2. Behaviour and larve sources of Aedes aegypti and Ae. albopictus.
Binh Dinh province: Adult of Ae. aegypti were collected mainly indoor (99.4%) and resting in clothes
(75.7-86% follow landscapes), bed net (10.9%-17.9% follow landscapes) and found resting on the wall in
urban (1.3%). The key breeding sites were ornamental plant pot, buckets, jars, tires and flower pots.
Gia Lai province: the rate of adult Ae. aegypti collected indoor (95.4%) and outdoor (4.6%), for Ae.
albopictus the collecting of indoor and outdoor were 12.5% and 87.5% respectively. Ae. aegypti rest
mainly in bed nets (33-53.2%), clothes (30.2%-60.8%) and 0.3% mosquitoes was found resting on the
wall. Ae. albopictus was also found resting on the wall in the rural areas 1 (3.9%). The key breeding sites
were cement tanks, drums, buckets, tires and flower pots.
1.3. The dengue virus infection rate of Aedes aegypti and Ae. albopictus
Only Ae. aegypti samples collected from urban were found infected with dengue virus. The dengue virus
infection rate of Aedes aegypti and Ae. albopictus were 0.82% in Binh Dinh and 0.95% in Gia Lai.
2. Susceptibility of Aedes to insecticide.
Aedes aegypti and Ae. albopictus collected from Binh Dinh and Gia Lai provinces was found resistant to
alphacypermethrin, lambdacyhalothrin, deltamethrin, permethrin. However, both of species were still
susceptible to malathion.
Ae. aegypti and Ae. albopictus populations from Binh Dinh and Gia Lai provinces were resistant to
lambdacyhalothrin, deltamethrin, permethrin and alphacypermethrin. However, both species remained
sensitive to malathion in all the sites of the two provinces.
The proportion of samples of Ae. aegypti with mutation were 52% in urban areas, 48% in flatlands and 28
in mountainous areas of Binh Dinh and 56% in urban areas, 48% in rural areas 1 and 32% in rural areas 2
of Gia Lai province.
Binh Dinh province: Two kdr mutations (L982W and V1016G) in domain II were identified in Ae.
aegypti populations from urban areas and flatlands, but only found V1016G mutation in the mountainous

samples. Furthermore, co-occurrence of kdr mutations (L982W and V1016G, 7.7%) appeared in one
same sample of Ae. aegypti mosquito in urban. In Gia Lai, only kdr mutation L982W (100%) were
detected in all the samples.

Promotors
1. Dr. Nguyen Xuan Quang
2. Dr. Huynh Hong Quang

Hanoi, July 10th, 2019
Ph.D Student

Do Van Nguyen