The growth of human populations and the rapid destruction of forested habitat are bringing humans and wildlife into ever-increasing contact. What does this amplified interaction mean for global public health and biodiversity? Concern has grown in recent years as the potential threat for emerging infectious disease (EID) from wildlife reservoirs has become a tangible risk. Zoonotic pathogens, or those stemming from animal origin, comprise nearly 75 percent of the 1,500 species of infectious organisms detrimental to humans. Occurrences of cross-species disease transfer, such as Nipah virus, Ebola, and HIV (from SIV), have occurred more frequently as humans move into uninhabited forest areas.
Nowhere is this issue more pertinent than in Madagascar, where nearly 90 percent of original forest cover has already been lost to deforestation for resource extraction, rice cultivation, and cattle grazing. Village expansion has spread into previously uninhabited areas, increasing wildlife contact. Pathogen “spill-over” from domestic animals into wildlife reservoirs can cause local population extinctions and can potentially move back into novel domestic animal and human hosts. These threats are especially relevant when considering primate hosts, such as lemurs, because of the closer phylogenetic relationship to humans. Researchers have documented cases of malaria, West Nile Virus, E. coli, and Toxoplasmosis within lemur populations; all of these diseases could potentially be transferred among human, domestic, and wildlife hosts.
My research focuses on the impacts of increasing human development on lemur health in Madagascar. I am looking at how escalating rates of contact between wildlife and humans could heighten the probability of EID and threaten biodiversity. Consistent baseline health monitoring provides an effective tool for evaluating wildlife health and also serves as an early warning sign in the occurrence of an epizootic outbreak. By capturing the lemurs, we can conduct health evaluations on a number of different species throughout Madagascar. When evaluating the lemur individual, we assess the general body condition of the lemur (teeth, coat, eyes, ears) and also collect useful specimens, such as fecal samples, hair and a small amount of tissue. With these data, we can assess body condition, examine the parasite diversity within a population, measure the amount of stress that the population is experiencing, and figure out how genetic diversity influences health. By incorporating this information with assessments of the site quality and levels of human exposure, we can figure out how human development influences lemur health and biodiversity. Additionally, we can develop predictive tools for assessing disease emergence risk, which can inform both conservation and public health agencies in their planning.
To find out more about my project, (funded, in part, by the Duke University Center for International Studies’ Graduate Awards for Research & Training), as well as what life is like in the field in Madagascar, please check out my blog at: lemurhealth.blogspot.com