Contact Us  |  Search  
The National Academies of Sciences, Engineering and Medicine
Partnerships for Enhanced Engagement in Research
Development, Security, and Cooperation
Policy and Global Affairs
Home About Us For Applicants For Grant Recipients Funded Projects Email Updates
Cycle 7 (2018 Deadline)

Developing dengue risk predictions from environmental, entomological, and societal information to aid public health management in Sri Lanka

PI: Pahalagedera Hewayalage Dona Kusumawathie (, Tropical Climate Guarantee
U.S. Partner: Aravinda de Silva, University of North Carolina Chapel Hill
Dates: November 2018 - October 2020

Project Website:

Project Overview:

Dengue is a major vector-borne viral disease that has become a serious public health problem in Sri Lanka and elsewhere, but the lack of a vaccine against it means that control programs rely on management of environmental and human factors. Dengue is highly intermittent, has some seasonality, and is showing an exponential rise in the last few decades (Hopp & Foley, 2003). Dengue outbreaks are primarily associated with climatic variables such as rainfall, temperature, and relative humidity. Usually peak transmission occurs after the rains in the areas where the mosquito population is high and temperature and humidity levels are optimal. Nevertheless, there can be situations where transmission is enhanced during droughts, as water storage becomes more important. Though the risk of epidemics is contingent on a complex set of social, environmental, climatic, and epidemiological factors and their prediction is fraught with uncertainty, climate is a critical factor. As there is a 1-2 month lag between heavy rains and dengue transmission, targeted weather monitoring can give advance warning of dengue risks and trigger alerts to the authorities to launch cleanup programs of potential breeding sites.

7-201 Balika Training7-201 Lab Test
Project team members teaching at the Muslim Balika Vidyalaya event.Dr. Kusumawathie preparing to observe mosquito eggs through the digital microscope (photos courtesy of Dr. Kusumawathie)

To address the problem of dengue in Sri Lanka, this project involves entomological surveillance, weather and climate impact analysis, vulnerability analysis, and the development of monitoring systems for mosquito abundance and vulnerability. The scientific objectives are to (1) identify relationships between prevalence and transmissivity of the dengue vectors and weather using routinely collected data; (2) identify relationships between abundance of vectors, incidence of dengue, and weather in the country’s Central Region; and (3) develop dengue risk prediction methodology based on weather for high-risk centers. Through these efforts the PI and her team will develop an early warning system for dengue risk using weather, climate, entomological and epidemiological information for Sri Lanka, working in close collaboration with the Central Province Health Department and National Dengue Control officials. These government officials will be engaged in helping to develop the risk prediction methodology and formats for dissemination. The PI and her team will share their results and recommendations with public health officers and other interested stakeholders via the Internet and in-person workshops.

Summary of Recent Activities:

During the last quarter of 2019, Dr. Kusumawathie and her team filled some of the critical data gaps on their project with regard to available dengue cases and entomological, demographic and meteorological data. The data collected include national level climate data with a focus on the Central and surrounding provinces, and the researchers are still working on collecting additional meteorological data (rainfall, temperature, and humidity) up to 2019. Recently they met with health officials from the North-Western Province to discuss their project and request their assistance in obtaining data from their jurisdiction, which neighbors Central Province.

The PI and her group have organized the data into databases and mapped some of the data. An animation of national-level monthly district maps is now available from 2001 to 2019, as is an animation of sub-district data for each of the districts in the Central Province for this same duration, with some gaps still to be filled. In addition, mapping of village-level data has been undertaken in two sub-districts. These animations will be included on a Web page that is currently under development.

The PI reports that her laboratory instruments are functioning, and she and her team are carrying out some trials on assessing the impact of temperature on the gonotrophic cycle of vector insects. The researchers continue to maintain their own weather stations, and they are also collaborating with partners to gather data from their networks.

Overall, the project is on track, although the team is several months behind schedule due to security-related disruptions during 2019. Planned activities for the first half of 2020 will follow the original work plan, focusing on analysis of the impacts of the built environment, urbanization, and demographic factors; data sharing and network building with stakeholders in the health sector; preparation of technical reports and journal articles; and outreach and dissemination through various channels.

Back to PEER Cycle 7 Grant Recipients