Environmental Epidemiology in Latin America: Leishmania (2015-2016)
For the past three years, we have run a successful Bass Connections project in Peru to train students in field epidemiology and bench-to-field science focused on understanding human health impacts from ongoing environmental change due to gold mining, road construction and heavy metal exposure. This year’s team continues this theme by focusing on cutaneous leishmaniasis. Leishmaniasis is a neglected tropical disease that is transmitted by a phlebotomine sandfly. While the total number of cases reported in South America is relatively low (200,000-300,000 annually), Peru has the second highest incidence rate, and our study region, which is the Andean-Amazon areas of Madre de Dios and Cusco, accounts for 30% of all cases reported. There is little information available regarding the ecology of vectors for leishmania, particularly pertaining to preferred locations of reproduction and animal reservoirs of infection.
The purpose of this project is to learn about the current epidemiology and state of science regarding leishmaniasis, including vector ecology, transmission dynamics, cutaneous vs. visceral forms of disease, treatment options and designing and implementing a field-based ecological study of leishmania vectors and (potential) hosts. Students will be trained in ecological sampling, sandfly morphology and animal biology as well as sample collection, storage and processing in the field. The project also includes working with the Ministry of Health to conduct prevalence surveys of infection and with the US Naval Medical Research Unit-6 (NAMRU-6) to conduct parasitology tests on identified patients having active skin lesions. Lastly, this project includes developing molecular screens that can be used for improving the detection of sandflies in environmental samples. This will involve using archived sandflies from prior years and developing (or identifying) molecular tools that can be used to identify different sandfly species.
In June 2016 the team traveled to Peru. Student team members were interviewed live on Yurimaguas TV about environmental health.
Also in June 2016, an article in Nature highlighted the impact of the Bass Connections research over the past three years. Describing how a gold-mining boom in southeastern Amazon is driving high levels of mercury contamination, the article cited Duke research that “found high levels of mercury (above the maximum recommended by the World Health Organization) in hair samples from 40% of the Madre de Dios residents that they tested. The Duke team has examined about 800 people living along a major highway in the region, 100 people living beside the river and 2,000 in the Amarakaeri Indigenous Reserve.... Peru’s government used the Duke team’s latest study to determine which riverside communities should receive the emergency aid.”
October 2015 - December 2016
Lauren H. Wyatt, Sarah E. Diringer, Laura A. Rogers, Heileen Hsu-Kim, William K. Pan, Joel N. Meyer. “Antagonistic Growth Effects of Mercury and Selenium in Caenorhabditis Elegans Are Chemical Species-Dependent and Do Not Depend on Internal Gs/SE Ratios” 2016. Environmental Science and Technology. 50:3256-3264.
William Pan, Developing an Early Warning System for Malaria Risk in the Amazon ($1,000,000 grant awarded from the National Aeronautics and Space Administration, 2015)
Malaria and Leishmaniasis in Loreto and San Martin, Peru (poster by Jennifer Callejas, Liane Emerson, Joshua Grubbs, Luiza Perez, Huijia Yu, Elizabeth Monahan and Justin Lana)
Risk Factors for Cutaneous Leishmaniasis in the Alto Mayo Region of Peru (poster by Justin Lana)
Evaluating the Effectiveness of Permethrin and Deltamethrin in the Northern Peruvian Amazon (poster by Elizabeth Monahan)
Duke Global Health Institute People’s Choice Award for “Jesus and Ernesto” (photo by Liane Emerson)
This Team in the News
- Joel Meyer, Nicholas School of the Environment-Environmental Sciences and Policy
- Ernesto Ortiz, Duke Global Health Institute
- William Pan, Nicholas School of the Environment-Environmental Sciences and Policy
/graduate Team Members
Justin Lana, Global Health - MS
Elizabeth Monahan, Global Health - MS
/undergraduate Team Members
Jennifer Callejas, Environmental Sci/Policy (AB), Global Health (AB2)
Liane Emerson, Biology (BS), Global Health (AB2)
Joshua Grubbs, Chemistry (AB), Global Health (AB2)
Luiza Perez, Sociology (AB), Global Health (AB2)
Huijia Yu, Statistical Science (BS), Computer Science (BS2)
/zcommunity Team Members
Peru Ministry of Health
US Naval Medical Research Unit-6 (NAMRU-6)