Mission

Mission- is to provide world-class entomologic, epidemiologic and ecologic research on vector-borne diseases in support of US troops engaged in military operations. The department conducts research on all aspects of the transmission of malaria, arboviruses, and rickettsial diseases with an emphasis on suppression. These are the vector-borne diseases that pose the greatest threat to troops in tropical regions. Interagency and interdepartmental collaborations have and continue to be a central focus in mission accomplishment.

Collaborative partners: Naval Medical Research Unit-2, 18th Medcom, Republic of Korea, USAMRIID, CHPPM-PAC and CINCPAC, University of North Dakota (NIH R01 grant)

In the tropical world as well as in some well-developed countries, vector-borne infectious diseases are still one of the major public health problems. Thailand is located in the heart of the endemic area for several vector-borne diseases. Furthermore, a large amount of national budget is also spent on treatment of the vector-borne diseases patients. The Center is established with an aim to strength the capacity of the team for researching and training on vector biology in Southeast Asian region and to coordinate scientific researches concerning disease vector and related topics at regional, national and international levels.

Research Areas

The research focal areas include:

Population biology and population genetics of the vectors and their relationship with the pathogens
The study will provide the baseline data for the future application of control technologies to the field population of vectors. Research along this line involves the study on biodiversity and coevolution of vectors, pathogens and symbiotic microbes that have the potential to be used for future genetic control. Other baseline data on vectors and vector-borne pathogens such as insecticide resistance will be studied.

Vector control methodologies
This area ranges from appropriate technologies that could be applied at the community level to the molecular-based technologies for future vector control approaches. The goal of research for short-termed vector control is to improve the practical community-based vector control technologies such as insecticide-coated bed nets for malaria control or insecticide-coated resting boxes for dengue control whereas for the long term is to find cost-effective and practical vector control methodologies as well as to search for the future promising vector control approaches.

Molecular ecology of the malaria parasite population and their vector specificity in Thailand
This project aims at studying molecular ecology, population structure and epidemiology of malaria parasites and their Anopheles mosquito vectors in different areas of Thailand bordering Cambodia and Myanmar. Cloning and sequencing of ten microsatellite loci and antigen loci of Plasmodium falciparum and Plasmodium vivax, including microsatellite markers developed for Anopheles dirus will be conducted. Data will be used to determine population structure and coevolution of these parasites and their main host.

Monitoring of insecticide resistance and mapping of malaria vectors in Southeast Asia: A prerequisite for sustainable malaria vector control.
New tools for improving sustainable control of malaria vectors in Southeast Asia will be developed. An adapted monitoring system to detect early development of insecticide resistance will be set up. We will develop molecular and biochemical tests to explore the resistance mechanism involved. At the end of the project, the insecticide resistance status will be available for at least 120 sites and a decision tree for the management of operational implications will be available. A Geographic Information System (GIS) on vector distribution and insecticide resistance will be developed. We will develop a model to predict vector distribution and associations of species by environmental factors. This will be a practical tool to delineate malaria risk areas to improve the targeting of vector control and assessing the resistance status of vectors.

Suppression of dengue transmission by focal vector control
This project aims to develop a cost-effective dengue vector control model for rural communities. We hypothesize, based on our previous serological data, that suppression of dengue vectors at foci within a village and in schools will effectively reduce dengue transmission throughout the community. The identification of foci will involve an integration of serosurvey and spatial GIS mapping of the study area. Our study design should also determine whether vector control efforts in villages or in schools or both are necessary to suppress transmission. The vector control methodologies will be an environmental-friendly, integrated, community-based approach using locally-made screen covers and the combination of local BTI toxin and local predaceous crustacean for controlling mosquito larvae. Lethal ovitraps will be added to control adult vector populations.

Densoviruses as transducing vector
Our project carried out in Thailand with the aim to Survey for novel strains of densoviruses in different mosquito species, mainly in genera Aedes, Anopheles and Culex in Thailand. The densoviruses found in different species of mosquitoes will be isolated and characterized. Complete genome sequencing of these viruses will be carried out. Studying infectivity and vertical transmission of these densoviruses and also the chimeric densoviruses constructed from the Colorado State University in the mosquito vectors in order to map the genes responsible for vilurence, infectivity, vertical transmission or other viral properties. The ultimate goal of this project is to develop densovirus as the tranducing vectors to express genes in the mosquito vector in an attempt to genetically control them.

Crustacean Wolbachia: strain diversity and host effect
This project aims at studying strain diversity and distribution of Wolbachia bacteria in crustacean hosts inhabiting fresh water and intertidal zone including the mangrove forests. This group of Wolbachia bacteria is poorly known in the tropics. The crustacean Wolbachia are known to cause feminization of genetic male hosts and this property may be useful for cost-effective mass-culturing of commercial or beneficial crustaceans. In this project, the effect of crustacean Wolbachia on different hosts will be investigated. The use of feminizing property of certain Wolbachia strain in mass-rearing of crustacean copepods, a mosquito larval predator used for biological control of mosquito vectors, will be studied. The use of these feminizing strains of Wolbachia for mass-rearing of fairly shrimps for commercial purpose will also be investigated.

Molecular ecology and vector capacity of tick and mite
This project aims to survey on distribution and variation of vectors and their related pathogens and to study epidemiology and prevalence of the diseases in Thailand.