Detection of dengue viruses and Wolbachia in Aedes aegypti and Aedes albopictus larvae from four urban localities in Kuala Lumpur, Malaysia
- Author:
Teo, C.H.J.
;
Voon, K.
;
Mak, J.W
- Publication Type:Original Article
- From:Tropical Biomedicine
2017;34(3):583-597
- CountryMalaysia
- Language:English
-
Abstract:
Dengue fever (DF) is currently one of the most important mosquito-borne diseases
that affects humans. Dengue fever (DF) and dengue hemorrhagic fever (DHF) are caused by
four serotypes of dengue viruses (DENV-1 to DENV-4). The main vector transmitting dengue
is Aedes aegypti while Aedes albopictus acts as a secondary vector. As treatment is unavailable
and the first dengue vaccine approved in Mexico, Dengvaxia® has yet to be accepted worldwide,
prevention of the disease relies heavily on surveillance and control of mosquito vectors.
A transgene driver, Wolbachia was found to limit the transmission of dengue virus in Aedes
mosquitoes. Wolbachia alone was able to inhibit viral replication, dissemination and
transmission in A. aeygpti mosquitoes in experimental studies. In A. albopictus, Wolbachia
did not affect the replication of dengue virus but was able to reduce the viral infection of
mosquito salivary glands and limit transmission. Studies on Wolbachia have all been carried
out in adult Aedes mosquitoes, hence this study was conducted to determine the presence of
dengue virus serotypes and Wolbachia in A. aegypti and A. albopictus larvae collected from
ovitraps in four localities in Kuala Lumpur viz. Happy Gardens, IMU Bukit Jalil, Ampang and
Taman Yarl. Another objective of this study was to determine the association between dengue
virus serotypes and the presence of Wolbachia in A. aegypti and A. albopictus larvae. A total
of 300 mosquito larvae was collected; 99 (Happy Gardens), 85 (Bukit Jalil), 73 (Ampang) and
43 (Taman Yarl). Out of 300 larvae collected, 284 were identified as A. albopictus and 16
others were identified as A. aegypti. Of the 284 A. albopictus larvae collected, 211 (74.3%)
and 73 (25.7%) were found to be negative and positive for dengue virus respectively. The
dengue serotypes detected were 2 DENV-2 (2.7%), 58 DENV-3 (79.5%) and 13 DENV-4 (17.8%).
DENV-1 was not detected in any of the A. albopictus larvae. For A. aegypti, out of 16 A.
aegypti larvae collected, 12 (75%) were found to be negative and 4 (25%) were positive for
DENV-2. For the detection of Wolbachia in A. albopictus, 71 out of 284 (25%) and 213 (75%)
larvae were found to be positive and negative for Wolbachia respectively. For A. aegypti, 4
(25%) and 12 (75%) out of 16 larvae were positive and negative for Wolbachia respectively.
This is the first report of Wolbachia in A. albopictus and A. aegypti larvae in Malaysia. A chisquare
test analysis to determine the association between dengue virus and Wolbachia in A.
albopictus and A. aegypti larvae collected from the four localities in Kuala Lumpur showed
that there was no association (χ2 = 3.080; df = 1; P > 0.05).
