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British Journal of Healthcare and Medical Research - Vol. 11, No. 3
Publication Date: June 25, 2024
DOI:10.14738/bjhmr.113.16931.
Tawatsin, A., Thavara, U., Yowang, A., Jitphayak, U., & Srivarom, N. (2024). The Control of Dengue Hemorrhagic Fever Using
Innovations for The Integrated Controlling Aedes Mosquitoes. British Journal of Healthcare and Medical Research, Vol - 11(3). 51-
62.
Services for Science and Education – United Kingdom
The Control of Dengue Hemorrhagic Fever Using Innovations for
The Integrated Controlling Aedes Mosquitoes
Apiwat Tawatsin
Medical Science Technical Office, Department of Medical Sciences,
Nonthaburi 11000, Thailand
Usavadee Thavara
Consultant, Department of Medical Sciences,
Nonthaburi 11000, Thailand
Amara Yowang
Regional Medical Sciences Center 1/1 Chiang Rai,
Department of Medical Sciences, Chiang Rai 57100, Thailand
Udorn Jitphayak
Regional Medical Sciences Center 1/1 Chiang Rai,
Department of Medical Sciences, Chiang Rai 57100, Thailand
Navy Srivarom
Medical Science Technical Office, Department of Medical Sciences,
Nonthaburi 11000, Thailand
ABSTRACT
Dengue hemorrhagic fever (DHF) is an infectious disease transmitted to humans by
Aedes aegypti and Ae. albopictus mosquitoes. The prevention and control of these
vector mosquitoes are the main strategies to control the disease since no effective
vaccine is available for prevention. This project aimed to reduce the Aedes
mosquito populations in the study areas using the three innovations of the
Department of Medical Sciences (LeO-Trap: lethal ovitrap, AZAI: Aedes larvicide,
and RepelMos: mosquito repellent) with community participation. The study was
conducted in Chiang Rai Province (Muang District) and Phrae Province (Muang
District and Song District) as these provinces were predicted as the potentially
epidemic areas of DHF in 2022. The study areas were 2 villages (approximately 100
houses/village) selected from each District; as a result, 815 houses from these 6
villages participated in this study. The owner of each house received 4 sets of LeO- Trap (2 traps for use inside the house and 2 traps for use outside the house), 4 bags
(100 g.) of AZAI, and 2 bottles (40 ml.) of RepelMos. Overall, the village health
volunteers collected the sponge sheets (substrate for egg laying of Aedes
mosquitoes) from the total treated houses ranged from 78% to 100% while the
houses positive for Aedes eggs were between 29.6% and 100%. The total number
of Aedes eggs collected from inside and outside the houses of the 6 villages in this
study was 282,160 eggs; therefore, it could be estimated that 70,540,000 Aedes
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British Journal of Healthcare and Medical Research (BJHMR) Vol 11, Issue 03, June-2024
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mosquitoes were rid of by the LeO-Trap in the study areas based on the assumption
that a female mosquito could produce 500 offspring in her lifetime. Regarding the
data collected by Sub-district, the highest numbers of Aedes eggs were collected
from Nang Lae Sub-district in Muang District, Chiang Rai Province (117,557 eggs
with an average 87 eggs/house),followed by Hua Muang Sub-districtin Song District,
Phrae Province (99,326 eggs with an average 97 eggs/house) and Mae Kam Mee Sub- district in Muang District, Phrae Province (65,277 eggs with an average 62
eggs/house). Overall, the number of Aedes eggs collected by the LeO-Trap inside the
houses was higher than those obtained outside the houses in the three sub-districts.
The results obtained from this study indicated that the innovations used in this
project with community participation could substantially reduce Aedes mosquito
populations in the study areas and reduce the incidence of DHF. This study could be
a model for preventing and controlling Aedes mosquitoes in other areas.
Keywords: Aedes aegypti, Dengue, Lethal ovitrap, Control
INTRODUCTION
Aedes aegypti and Ae. albopictus mosquitoes are the primary vectors for dengue hemorrhagic
fever, chikungunya, and Zika viruses [1-4]
. These mosquito species are known for their role in
transmitting arboviruses, including dengue, chikungunya, and Zika, which have significant
public health implications due to their global spread and associated health consequences [3]
.
Studies have shown that Aedes aegypti and Aedes albopictus are highly competent in
transmitting these arboviruses, highlighting the importance of understanding the factors
affecting virus transmission from mosquitoes to humans for effective public health
interventions. The presence of these vectors in urban environments poses a significant risk for
the transmission of these diseases, emphasizing the need for targeted vector control strategies
to mitigate the impact of dengue, chikungunya, and Zika infections. Understanding the factors
influencing virus transmission from these vectors to humans is essential for public health
interventions and targeted control measures. Additionally, controlling these mosquito vectors
through strategies like biological insecticides can help break the transmission chain of dengue
hemorrhagic fever. The main strategies to control Ae. aegypti and Ae. albopictus include
integrated vector management, sterile insect technique (SIT), and the use of larvicides,
insecticides, and biological control methods [5-6]
. Integrated vector management, as promoted
by the World Health Organization, emphasizes a holistic approach considering biological,
genetic, chemical, physical, and cultural control methods tailored to the local context [7]
.
Additionally, the use of larvicides, and insecticides, has been shown to effectively reduce the
population of Ae. aegypti, at the beginning of each seasonal period being identified as a cost- effective control strategy. The lethal ovitrap (LO) has shown significant effectiveness in
controlling Aedes mosquitoes. Studies have demonstrated that the application of lethal ovitraps
led to a decline in Aedes mosquito density, with some experiments showing a reduction in
mosquito populations by attracting gravid mosquitoes and killing newly emerged larvae [8-9]
.
Additionally, a novel durable dual-action lethal ovitrap (DDALO) designed for Aedes aegypti
displayed high adult mosquito mortality and prevented successful hatching of eggs, making it a
promising tool for controlling wild vector populations [10]
. Community participation plays a
crucial role in Aedes mosquito control efforts. Studies have shown that engaging communities
through various methods such as workshops, seminars, and knowledge sharing can lead to a
significant reduction in Aedes larval indices. Additionally, community perceptions and
involvement can help in identifying challenges and implementing effective solutions for
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Tawatsin, A., Thavara, U., Yowang, A., Jitphayak, U., & Srivarom, N. (2024). The Control of Dengue Hemorrhagic Fever Using Innovations for The
Integrated Controlling Aedes Mosquitoes. British Journal of Healthcare and Medical Research, Vol - 11(3). 51-62.
URL: http://dx.doi.org/10.14738/bjhmr.113.16931.
mosquito control projects [11]
. Furthermore, community members' knowledge, attitudes, and
practices toward mosquito management influence their behaviors, highlighting the importance
of addressing misconceptions and promoting appropriate control methods [12]
. Overall,
community participation is essential for sustainable Aedes mosquito control by fostering
awareness, cooperation, and effective implementation of preventive measures. This study
aimed to reduce the Aedes mosquito populations in the study areas using the three innovations
of the Department of Medical Sciences (LeO-Trap: lethal ovitrap, AZAI: Aedes larvicide, and
RepelMos: mosquito repellent) with the community participation approach.
MATERIALS AND METHODS
The study was carried out in 2 Provinces, Chiang Rai and Phrae. In Chiang Rai, 2 villages: Village- 8 (151 houses) and Village-13 (282 houses) in Nang Lae Sub-district, Muang District, were
chosen for the experiment. As for Phrae, the experiment was conducted in 4 villages: Village-2
(68 houses) and Village-7 (112 houses) of Hua Muang Sub-district, Song District, and Village-9
(103 houses) and Village-10 (99 houses) of Mae Kam Mee Sub-district, Muang District. These
villages were selected as the study areas according to what they were forecasted as risk areas
of the DHF epidemic in 2021 by the Department of Disease Control, Ministry of Public Health,
Thailand. Before the initiation of the project, the village health volunteers (VHVs) of each village
were educated on the etiology of DHF and the biology and ecology of the mosquito vectors that
transmit the disease: Ae. aegypti and Ae. albopictus. The prevention and control of the disease
and the mosquito vectors were also elaborated clearly. In this study, we used 3 innovations
developed by the scientists of the Department of Medical Sciences, Ministry of Public Health,
Thailand to reduce the Aedes populations in the areas. These innovations were LeO-Trap (lethal
ovitrap), AZAI (Aedes larvicide, containing 1% temephos as the active ingredient), and
RepelMos (mosquito repellent, containing 20% DEET as the active ingredient) (Figure 1), and
they were implemented in areas with community participation driven by VHVs of each village.
All VHVs were trained on how to use these innovations properly. LeO-Trap is a lethal ovitrap
filled with about 500 ml of water and had an attractant (carpet shell extract) to lure gravid
Aedes females to lay their eggs on the sponge sheet (substrate for egg laying of Aedes
mosquitoes)in the trap and about 1 g of AZAI was also added in the trap to kill all larvae hatched
from eggs. The owner of each house received 4 sets of LeO-Trap (2 traps for use inside the house
and 2 traps for use outside the house), 4 bags (100 g.) of AZAI, and 2 bottles (40 ml.) of
RepelMos (Figure 1). The owners of the houses were informed to use LeO-Trap properly, refill
the water in each trap every two weeks, and replace the AZAI in the trap every three months.
The AZAI would be used in water-storage containers infested with Aedes larvae to get rid of the
larvae while the RepelMos would be applied on bodies to prevent Aedes biting. The VHVs
collected the sponge sheets from the owner of the treated houses once a month and the number
of mosquito eggs on each sheet was counted and recorded. During this study, we used the LINE
application to communicate with VHVs in all villages. This is an effective social media to provide
knowledge and help them to solve the problems that might occur during their contact with the
villagers.
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British Journal of Healthcare and Medical Research (BJHMR) Vol 11, Issue 03, June-2024
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Figure 1: The 3 innovations: LeO-Trap, AZAI, and RepelMos were used in this study.
RESULTS
Table 1 shows the results of the houses infested with Aedes mosquito eggs using LeO-Trap in
the areas of Village-8 (151 houses) and Village-13 (282 houses) ofNang LaeSub-district, Muang
District, Chiang Rai Province, including a total of 433 houses during the study period of 6
months. It was found that the VHVs were able to collect the sponge sheets from the trapped
houses of both 2 villages as compared to all surveyed houses ranging from 81.1% to 95.4%. The
houses infested with Aedes mosquito eggs ranged from 31.3% to 78.3%. Regarding each village,
the VHVs in Village-8 were able to collect sponge sheets from the trapped houses as compared
to all surveyed houses with the range from 84.8% to 100% with infested rates of mosquito eggs
ranging between 34.4% and 91%. On the other hand, the VHVs in Village-13 could collect
sponges from the trapped houses as compared to all surveyed houses from the range of 78% to
100%. The infested rates of houses infested with Aedes mosquito eggs were between 29.6%
and 82.7% (Table 1).
Table 1: The total number of surveyed houses and Aedes eggs-infested houses
employing LeO-trap in Village-8 and Village-13 of Nang Lae Sub-district, Muang District,
Chiang Rai Province during the study period of 6 months.
Places Houses Total number ofsurveyed houses and Aedes eggs-infested houses(%)
by month
Total
Month-1 Month-2 Month-3 Month-4 Month-5 Month-6
Village-8 Surveyed
houses
151
(100%)
131
(86.8%)
134
(88.7%)
136
(90.1%)
150
(99.3%)
128
(84.8%)
830
(91.6%)
Infested
houses
79
(52.3%)
75
(57.3%)
122
(91%)
104
(76.5%)
74
(49.3%)
44
(34.4%)
498
(60.0%)
Village- 13
Surveyed
houses
220
(78%)
282
(100%)
276
(97.9%)
262
(92.9%)
223
(79.1%)
223
(79.1%)
1,486
(87.8%)
Infested
houses
182
(82.7%)
157
(55.7%)
199
(72.1%)
145
(55.3%)
110
(49.3%)
66
(29.6%)
859
(57.8%)
Total Surveyed
houses
371
(85.7%)
413
(95.4%)
410
(94.7%)
398
(91.9%)
373
(86.1%)
351
(81.1%)
2,316
(89.1%)
Infested
houses
261
(70.4%)
232
(56.2%)
321
(78.3%)
249
(62.6%)
184
(49.3%)
110
(31.3%)
1,357
(58.6%)
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Tawatsin, A., Thavara, U., Yowang, A., Jitphayak, U., & Srivarom, N. (2024). The Control of Dengue Hemorrhagic Fever Using Innovations for The
Integrated Controlling Aedes Mosquitoes. British Journal of Healthcare and Medical Research, Vol - 11(3). 51-62.
URL: http://dx.doi.org/10.14738/bjhmr.113.16931.
A total of 117,557 Aedes mosquito eggs (average 87 eggs/house) were collected from 2 villages
of Nang Lae Sub-district, Muang District, Chiang Rai Province for the study period of 6 months
(Table 2). The total number of eggs trapped in the LeO-Trap (both inside and outside houses)
collected from the 2 villages was the highest number of 37,629 eggs in month 1 (average 144
eggs/house) and the lowest number of 9,684 eggs in month 5 (average 53 eggs/house) (Table.
2). Regarding the areas, it was found that the Village-8 had the highest number of 10,097 eggs
in month 3 (average 83 eggs/house) and the lowest number of Aedes mosquito eggs at 5,351
eggs (average 72 eggs/house) in month 5, while the Village-13 had the highest 28,621 eggs in
month 1 (average 157 eggs/house) and the lowest 4,079 eggs in month 6 (average 62
eggs/house) as shown in Table 2. In the total of the 2 villages, the number of Aedes mosquito
eggs in the LeO-Trap placed inside the houses was the highest (19,351 eggs) in month 1, and
the lowest (3,860 eggs) in month 6 (Table 2). Village-8 had the highest at 5,402 eggs in month
3, and the lowest number of Aedes mosquito eggs at 1,868 eggs in month 6. In Village-13, it was
found that the highest (14,303 eggs) was in month 1 and the lowest number of Aedes mosquito
eggs was 1,992 eggs in month 6 (Table 2).
The total number of Aedes mosquito eggs in the LeO-Trap placed outside the house (2 villages)
was the highest number at 18,278 eggs in month 1 and the lowest at 4,355 eggs in month 5 as
shown in Table 2. Village-8 had the highest at 4,695 eggs in month 3, and the lowest number of
Aedes mosquito eggs at 2,368 eggs in month 5, while the highest at 14,318 eggs of Aedes
mosquito eggs in month 1 in Village-13, and the lowest number was 1,987 eggs in month 5
(Table 2).
Table 2: The total number of Aedes mosquito eggs trapped in the LeO-Trap collected
from Village-8 and Village-13 of Nang Lae Sub-district, Muang District, Chiang Rai
Province for the study period of 6 months (both inside and outside houses).
Places Locations oftrapsin
houses
Number of mosquito eggs collected in the LeO-Trap by
month
Total
Month- 1
Month- 2
Month- 3
Month- 4
Month- 5
Month- 6
Village- 8
Inside 5,048 4,432 5,402 5,050 2,983 1,868 24,783
Outside 3,960 3,510 4,695 4,423 2,368 4,453 23,409
Total 9,008 7,942 10,097 9,473 5,351 6,321 48,192
Average/house 114 106 83 91 72 144 97
Village- 13
Inside 14,303 5,510 4,904 6,813 2,346 1,992 35,868
Outside 14,318 5,784 5,381 3,940 1,987 2,087 33,497
Total 28,621 11,294 10,285 10,753 4,333 4,079 69,365
Average/house 157 72 52 74 39 62 81
Total Inside 19,351 9,942 10,306 11,863 5,329 3,860 60,651
Outside 18,278 9,294 10,076 8,363 4,355 6,540 56,906
Total 37,629 19,236 20,382 20,226 9,684 10,400 117,557
Average/house 144 83 63 81 53 95 87
Table 3 shows the results of the houses infested with Aedes mosquito eggs using LeO-Trap in
the areas of Village-2 (68 houses) and Village-7 (112 houses) of Wang Fon Sub-district, Song
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District, Phrae Province, including a total of 180 houses during the study period of 6 months.
Overall, the VHVs were able to collect the sponge sheets from the trapped houses of both 2
villages as compared to all surveyed houses ranging from 97.8% to 99.4%. The houses infested
with Aedes mosquito eggs ranged from 94.3% to 98.9%. Regarding each village, the VHVs in
Village-2 were able to collect sponge sheets from the trapped houses as compared to all
surveyed houses with the range from 98.5% to 100% with infested rates of mosquito eggs
ranging between 92.5% and 100%. On the other hand, the VHVs in Village-7 could collect
sponges from the trapped houses as compared to all surveyed houses from the range of 97.3%
to 99.1%. The infested rates of houses infested with Aedes mosquito eggs were between 95.4%
and 99.1% (Table 3).
Table 3: The total number of surveyed houses and Aedes eggs-infested houses
employing LeO-trap in Village-2 and Village-7 of Hua Muang Sub-district, Song District,
Phrae Province during the study period of 6 months.
Places Houses Total number of surveyed houses and Aedes eggs-infested houses
(%) by month
Total
Month-1 Month-2 Month-3 Month-4 Month-5 Month-6
Village- 2
Surveyed
houses
67
(98.5%)
67
(98.5%)
67
(98.5%)
68
(100%)
68
(100%)
68
(100%)
405
(99.3%)
Infested
houses
67
(100%)
62
(92.5%)
62
(92.5%)
66
(97.1%)
64
(94.1%)
65
(95.6%)
386
(95.3%)
Village- 7
Surveyed
houses
111
(99.1%)
109
(97.3%)
110
(98.2%)
111
(99.1%)
110
(98.2%)
111
(99.1%)
662
(98.5%)
Infested
houses
109
(98.2%)
104
(95.4%)
105
(95.5%)
107
(96.4%)
109
(99.1%)
108
(97.3%)
642
(97.0%)
Total Surveyed
houses
178
(98.9%)
176
(97.8%)
177
(98.3%)
179
(99.4%)
178
(98.9%)
179
(99.4%)
1,067
(98.8%)
Infested
houses
176
(98.9%)
166
(94.3%)
167
(94.4%)
173
(96.1%)
173
(96.1%)
173
((96.1%)
1,028
(96.3%)
A total of 99,326 Aedes mosquito eggs (average 97 eggs/house) were collected from 2 villages
of Wang Fon Sub-district, Song District, Phrae Province for the study period of 6 months (Table
4). The total number of eggs trapped in the LeO-Trap (both inside and outside houses) collected
from the 2 villages was the highest number of 31,800 eggs in month 1 (average 91 eggs/house)
and the lowest number of 10,371 eggs in month 5 (average 31 eggs/house)(Table 4). Regarding
the areas, it was found that Village-2 had the highest number of 13,086 eggs in month 1 (average
195 eggs/house) and the lowest number of Aedes mosquito eggs at 3,670 eggs (average 57
eggs/house) in month 5, while the Village-7 had the highest 18,714 eggs in month 1 (average
172 eggs/house) and the lowest 6,701 eggs in month 5 (average 62 eggs/house) as shown in
Table 4. In the total of the 2 villages, the number of Aedes mosquito eggs in the LeO-Trap placed
inside the houses was the highest (16,000 eggs) in month 1, and the lowest (5,359 eggs) in
month 5 (Table 4). Village-2 had the highest number of 6,728 eggs in month 1, and the lowest
number of Aedes mosquito eggs at 1,852 eggs in month 6. In Village-7, it was found that the
highest (9,272 eggs) was in month 1 and the lowest number of Aedes mosquito eggs was 3,355
eggs in month 4 (Table 4). The total number of Aedes mosquito eggs in the LeO-Trap placed
outside the house (2 villages) was the highest number at 15,800 eggs in month 1 and the lowest
at 5,012 eggs in month 5 as shown in Table 4. Village-2 had the highest at 6,358 eggs in month
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Tawatsin, A., Thavara, U., Yowang, A., Jitphayak, U., & Srivarom, N. (2024). The Control of Dengue Hemorrhagic Fever Using Innovations for The
Integrated Controlling Aedes Mosquitoes. British Journal of Healthcare and Medical Research, Vol - 11(3). 51-62.
URL: http://dx.doi.org/10.14738/bjhmr.113.16931.
1, and the lowest number of Aedes mosquito eggs at 1,811 eggs in month 5, while the highest at
9,442 eggs of Aedes mosquito eggs in month 1 in Village-7, and the lowest number was 3,201
eggs in month 5 (Table 4).
Table 4: The total number of Aedes mosquito eggs trapped in the LeO-Trap collected
from Village-2 and Village-7 of Hua Muang Sub-district, Song District, Phrae Province
for for the study period of 6 months (both inside and outside houses).
Places Locations of traps in
houses
Number of mosquito eggs collected in the LeO-Trap by month Total
Month- 1
Month- 2
Month- 3
Month- 4
Month- 5
Month- 6
Village- 2
Inside 6,728 4,018 3,154 2,279 1,859 1,852 19,890
Outside 6,358 2,452 3,589 1,906 1,811 2,217 18,333
Total 13,086 6,470 6,743 4,185 3,670 4,069 38,223
Average/house 195 104 109 63 57 63 99
Village- 7
Inside 9,272 4,857 6,159 3,355 3,500 3,903 31,046
Outside 9,442 4,913 5,298 3,352 3,201 3,851 30,057
Total 18,714 9,770 11,457 6,707 6,701 7,754 61,103
Average/house 172 94 109 63 62 72 95
Total Inside 16,000 8,875 9,313 5,634 5,359 5,755 50,936
Outside 15,800 7,365 8,887 5,258 5,012 6,068 48,390
Total 31,800 16,240 18,200 10,892 10,371 11,823 99,326
Average/house 91 53 56 33 31 33 97
Table 5 shows the results of the houses infested with Aedes mosquito eggs using LeO-Trap in
the areas of Village-9 (103 houses) and Village-10 (99 houses) of Mae Kam Mee Sub-district,
Muang District, Phrae Province, including a total of 202 houses during the study period of 6
months. Overall, the VHVs were able to collect the sponge sheets from the trapped houses of
both villages as compared to all surveyed houses ranging from 97.5% to 100%. The houses
infested with Aedes mosquito eggs ranged from 74.8% to 95%. Regarding each village, the VHVs
in Village-9 were able to collect sponge sheets from the trapped houses as compared to all
surveyed houses with the range from 97.1% to 100% with infested rates of mosquito eggs
ranging between 76.7% and 96.1%. On the other hand, the VHVs in Village-10 could collect
sponges from the trapped houses as compared to all surveyed houses from the range of 98% to
100%. The infested rates of houses infested with Aedes mosquito eggs were between 72.7%
and 97% (Table 5).
Table 5: The total number of surveyed houses and Aedes eggs-infested houses
employing LeO-trap in Village-9 and Village-10 of Mae Kam Mee Sub-district, Muang
District, Phrae Province during the study period of 6 months.
Places Houses Total number of surveyed houses and Aedes eggs-infested houses
(%) by month
Total
Month-1 Month-2 Month-3 Month-4 Month-5 Month-6
Village- 9
Surveyed
houses
103
(100%)
100
(97.1%)
102
(99.0%)
103
(100%)
103
(100%)
103
(100%)
614
(99.3%)
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Infested
houses
79
(76.7%)
89
(89.0%)
86
(84.3%)
91
(88.3%)
97
(94.2%)
99
(96.1%)
541
(88.1%)
Village- 10
Surveyed
houses
99
(100%)
97
(98.0%)
99
(100%)
99
(100%)
99
(100%)
99
(100%)
592
(99.7%)
Infested
houses
72
(72.7%)
81
(83.5%)
89
(89.9%)
96
(97.0%)
89
(89.9%)
93
(93.9%)
520
(87.8%)
Total Surveyed
houses
202
(100%)
197
(97.5%)
201
(99.5%)
202
(100%)
202
(100%)
202
(100%)
1,206
(99.5%)
Infested
houses
151
(74.8%)
170
(86.3%)
175
(87.1%)
187
(92.6%)
186
(92.1%)
192
(95.0%)
1,061
(88.0%)
A total of 65,277 Aedes mosquito eggs (average 62 eggs/house) were collected from 2 villages
of Mae Kam Mee Sub-district, Muang District, Phrae Province for the study period of 6 months
(Table 6). The total number of eggs trapped in the LeO-Trap (both inside and outside houses)
collected from the 2 villages was the highest number of 12,644 eggs in month 2 (average 74
eggs/house) and the lowest number of 10,101 eggs in month 6 (average 53 eggs/house) (Table
6). Regarding the areas, it was found that Village-9 had the highest number of 6,512 eggs in
month 2 (average 73 eggs/house) and the lowest number of Aedes mosquito eggs at 5,108 eggs
(average 59 eggs/house) in month 3, while the Village-10 had the highest 6,132 eggs in month
2 (average 76 eggs/house) and the lowest 4,451 eggs in month 1 (average 62 eggs/house) as
shown in Table 6.
In the total of the 2 villages, the number of Aedes mosquito eggs in the LeO-Trap placed inside
the houses was the highest (6,992 eggs) in month 2, and the lowest (4,736 eggs) in month 6
(Table 6). Village-9 had the highest number of 3,747 eggs in month 2, and the lowest number
of Aedes mosquito eggs at 2,267 eggs in month 6. In Village-10, it was found that the highest
(3,247 eggs) was in month 4 and the lowest number of Aedes mosquito eggs was 2,077 eggs in
month 1 (Table 6).
The total number of Aedes mosquito eggs in the LeO-Trap placed outside the house (2 villages)
was the highest number at 5,652 eggs in month 2 and the lowest at 5,029 eggs in month 3 as
shown in Table 6. Village-9 had the highest at 2,923 eggs in month 1, and the lowest number of
Aedes mosquito eggs at 2,494 eggs in month 3, while the highest at 2,887 eggs of Aedes mosquito
eggs in month 2 in Village-10, and the lowest number was 2,210 eggs in month 5 (Table 6).
Table 6: The total number of Aedes mosquito eggs trapped in the LeO-Trap collected
from Village-9 and Village-10 of Mae Kam Mee Sub-district, Muang District, Phrae
Province during the study period of 6 months (both inside and outside houses).
Places Locations of traps in
houses
Number of mosquito eggs collected in the LeO-Trap by month Total
Month- 1
Month- 2
Month- 3
Month- 4
Month- 5
Month- 6
Village- 9
Inside 3,031 3,747 2,614 2,576 3,531 2,267 17,766
Outside 2,923 2,765 2,494 2,734 2,860 2,851 16,627
Total 5,954 6,512 5,108 5,310 6,391 5,118 34,393
Average/house 75 73 59 58 66 52 64
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Tawatsin, A., Thavara, U., Yowang, A., Jitphayak, U., & Srivarom, N. (2024). The Control of Dengue Hemorrhagic Fever Using Innovations for The
Integrated Controlling Aedes Mosquitoes. British Journal of Healthcare and Medical Research, Vol - 11(3). 51-62.
URL: http://dx.doi.org/10.14738/bjhmr.113.16931.
Village- 10
Inside 2,077 3,245 2,487 3,247 2,362 2,469 15,887
Outside 2,374 2,887 2,535 2,477 2.210 2,514 14,997
Total 4,451 6,132 5,022 5,724 4,572 4,983 30,884
Average/house 62 76 56 60 51 54 59
Total Inside 5,108 6,992 5,101 5,823 5,893 4,736 33,653
Outside 5,297 5,652 5,029 5,211 5,070 5,365 31,624
Total 10,405 12,644 10,130 11,034 10,963 10,101 65,277
Average/house 69 74 58 59 59 53 62
DISCUSSION
The LINE application was used in this study to provide essential information and help the VHVs
during their operation in the villages. One significant issue lies in the incapacity of the VHVs to
retrieve sponge sheets from LeO-Traps placed in certain households within the vicinity. This
difficulty arises when the homeowner relocates to a different area beyond the village for
employment purposes or misplaces the trap during its operation. Coupled with the challenge
posed by the COVID-19 pandemic in the region, the retrieval of sponge sheets from traps in
specific houses became unfeasible. Hence, village health volunteers play a crucial role as key
figures in the management of diseases within specific regions. Oversight of the activities aimed
at preventing and managing these diseases falls under the responsibility of the officials at the
Subdistrict Health Promotion Hospital within the responsible areas. Guidance on addressing
challenges and hindrances in the operations was closely offered by the personnel at the
Department of Medical Sciences.
In this study, LeO-Trap was used to collect Aedes mosquito eggs and the emerged larvae were
killed eventually by AZAI (1% temephos larvicide). LeO-Trap is a novel lethal ovitrap designed
to attract gravid female Ae. aegypti and Ae. albopictus mosquitoes and kill the emerged larvae,
significantly increasing oviposition efficacy and reducing adult populations in field experiments
[8]
. The trap combines a physically attractive design with a biochemical attractant from carpet
shell extract and a larvicide (AZAI) to effectively lure mosquitoes to lay eggs inside, leading to
the eventual elimination of larvae [8]
. The LeO-Trap was used for surveillance and control for
Ae. aegypti and Ae. albopictus in many places in Thailand [12-14]
.
Overall, the number of Aedes eggs collected by the LeO-Trap inside the houses was higher than
those obtained outside the houses in the three sub-districts. Some Aedes eggs collected inside
the houses were identified as Ae. aegypti only, while some of those retrieved from outside the
houses were identified as Ae. aegypti for 80-90% and Ae. albopictus for 10-20%. The total
number of Aedes eggs collected from inside and outside the houses of the 6 villages in this study
was 282,160 eggs; therefore, it could be estimated that 70,540,000 Aedes mosquitoes were rid
of by the LeO-Trap in the study areas based on the assumption that a female mosquito could
produce 500 offspring in her lifetime. Regarding the data collected by Sub-district, the highest
numbers of Aedes eggs were collected from Nang Lae Sub-district in Muang District, Chiang Rai
Province (117,557 eggs with an average 87 eggs/house), followed by Hua Muang Sub-district in
Song District, Phrae Province (99,326 eggs with an average 97 eggs/house) and Mae Kam Mee
Sub-district in Muang District, Phrae Province (65,277 eggs with an average 62 eggs/house). As
can be seen, a large number of Aedes eggs were collected from the 6 villages, and they were
decreased gradually over the study period. The people in all the villages have been satisfied
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British Journal of Healthcare and Medical Research (BJHMR) Vol 11, Issue 03, June-2024
Services for Science and Education – United Kingdom
with the decrease in Aedes mosquitoes in their houses. It is interesting to note that there was
no case of dengue or DHF in the 6 villages during the study period and even a year after that.
Therefore, implementing vector control interventions based on oviposition behavior to reduce
mosquito populations and pathogen transmission is crucial. Monitoring and controlling vector
species like Aedes aegypti using ovitraps, which are effective tools in epidemiological studies
and long-term mosquito control is thus important. Ovitraps with biological larvicide, Bacillus
thuringiensis israelensis (Bti) were also effective and safe for controlling Ae. aegypti and Ae.
albopictus, considering the number of eggs laid and the selectivity of pathogens for mosquitoes
[16]
.
The AZAI larvicide was also applied in some water-storage containers in the villages when the
VHVs or homeowners found Aedes larvae in the containers. A large number of containers
infested with Aedes larvae are usually found in the rainy season. Hidden larval habitats,
potentially created by rainwater in inconspicuous places, contributed to the mosquito
population. Therefore, it is important to get rid of the breeding places of Aedes mosquitoes as
much as possible to reduce Aedes populations. The use of RepelMos to prevent mosquito biting
is an important intervention to minimize vector-human contact. The application of repellent
lotion serves as a method to disrupt the interaction pattern between individuals and Aedes
mosquitoes, thereby offering an additional approach to dengue fever prevention. Furthermore,
it can deter the feeding activities of various mosquito vectors, including bothersome
mosquitoes and Anopheles mosquitoes. This could be the best way to prevent mosquito-borne
diseases via pathogen transmission as well as to reduce mosquito populations when the
mosquitoes lack blood meal. The villagers in this study were satisfied with the repellent
application when they had to be exposed to mosquitoes.
Dengue fever is always prevalent across all regions of Thailand. Consequently, efforts are
implemented to oversee and manage disease prevention. This undertaking must encompass
comprehensive coverage of all territories, particularly in regions with heightened susceptibility
to outbreaks. This involves the implementation of disease surveillance protocols and the
supervision of Aedes mosquito breeding sites in high-risk locations like residential areas,
educational institutions, religious sites, public parks, and tourist destinations. Effective risk
communication plays a crucial role in raising public awareness regarding the prevention of
dengue fever, particularly in anticipation of the upcoming rainy season. Such proactive
communication efforts are essential in averting extensive outbreaks and mitigating the severity
of cases during the epidemic period. To achieve this objective, a collaborative approach
involving multiple stakeholders is necessary, encompassing both public and governmental
entities.
The successful prevention and control of Aedes mosquitoes through the utilization of all three
innovations developed by the Department of MedicalSciences are highlighted in this study. This
achievement is attributed to the collaborative efforts of village health volunteers within the
community, who work in conjunction with homeowners assigned to each volunteer in every
village (approximately 10-15 houses per person). Furthermore, the active participation of the
homeowners plays a crucial role in this endeavor. The primary consideration in the
management of Aedes mosquitoes through the utilization of LeO-Trap pertains to the necessity
of replenishing the trap with water on a biweekly basis and replacing the AZAI that kills Aedes
larvae every three months. In the absence of these aforementioned procedures, the efficacy of
Page 11 of 12
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Tawatsin, A., Thavara, U., Yowang, A., Jitphayak, U., & Srivarom, N. (2024). The Control of Dengue Hemorrhagic Fever Using Innovations for The
Integrated Controlling Aedes Mosquitoes. British Journal of Healthcare and Medical Research, Vol - 11(3). 51-62.
URL: http://dx.doi.org/10.14738/bjhmr.113.16931.
Leo-Trap in attracting Aedes mosquitoes for oviposition and eradicating the hatched larvae will
be compromised. Consequently, the employment of LeO-Trap serves as a preventive measure
against the reproduction of mosquitoes that have previously ingested blood.
Effective communication of risks is essential in raising awareness about the prevention of
dengue fever, particularly in anticipation of the onset of the rainy season. Such efforts play a
crucial role in averting large-scale outbreaks and mitigating the impact of the disease during
epidemic periods. This initiative has engaged village health volunteers, who share collective
responsibility for its implementation. Utilizing the LINE application as a consistent and
frequent means of imparting information and addressing operational challenges within the
community. Communication is utilized to disseminate information regarding dengue fever and
the innovative strategies employed for the prevention and control of Aedes mosquitoes. The
promotion of enhanced comprehension among village residents is facilitated through the
dissemination of periodic audiovisual content reflecting local sounds. Achievement of these
objectives necessitates collaborative efforts from all sectors, encompassing both public and
governmental entities.
CONCLUSION
In conclusion, it was evidenced that the three innovations, especially the LeO-Trap used in this
study with community participation could substantially reduce Aedes mosquito populations in
the study areas. Close communication using the LINE application would be an effective tool to
provide important information for VHVs and villagers and solve problems that occur promptly,
especially during the COVID-19 epidemic period. It could affect the reduction of the disease.
This could be an effective model for the prevention and control of Aedes mosquitoes in other
areas.
ACKNOWLEDGMENT
The authors would like to thank the Public Health Academic Bureau, Office of the Permanent
Secretary, Ministry of Public Health for supporting the research budget. We also would to thank
the staff of the Regional Medical Sciences Center 1/1, Chiang Rai, the staff of Nang Lae Sub- district Health Promoting Hospital, Muang Chiang Rai District, Chiang Rai Province, and the
village health volunteers (VHVs) of Village-8 and Village-13, Nang Lae Subdistrict, Muang
District, Chiang Rai Province, the staff of Mae Kam Mee Sub-district Health Promoting Hospital,
the staff of Muang Phrae District, Phrae Province, and the VHVs of Village-9 and Village-10, Mae
Kam Mee Sub-district, Muang District, Phrae Province, and the staff of Wang Fon Sub-district
Health Promoting Hospital, Song District, Phrae Province, and the VHVs of Village-2 and Village- 7, Wang Fon Sub-district, Song District, Phrae Province, as well as the people in all 6 villages
who cooperated in the project.
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