Health as an Ecosystem Service Around Tanzanian Lakes and National Parks

2010-15 Seed Grant

The goal of this project is to increase the knowledge and understanding of the ecology and epidemiology of infectious diseases shared by domestic livestock and wildlife in East Africa. It focuses on the role that biodiversity, specifically near national parks in northern Tanzania, plays in buffering infectious disease outbreaks of zoonotic and vector borne diseases, such as schistosomiasis (snail fever), malaria and sleeping sickness, caused by parasitic worms (helminthes). It will also research worms that infect both humans and cattle. The team anticipates that this work will provide important insights to help shape health policy throughout sub-Saharan Africa.

Specifically, the project seeks to accomplish three key objectives:

  1. To quantify the distribution and abundance of zoonotic pathogens shared between humans, livestock, and wildlife in and around two Tanzanian national park;
  2. To quantify the extent to which wild species provide a major ecosystem service by protecting humans and domestic livestock against disease outbreaks; and
  3. To determine which pathogens are more of a threat to people living close to national parks and to develop ways to minimize these threats in order to minimize damage to wildlife.

Educational Impacts

This award supported five undergraduates who spent the summers of 2010 and 2011 in East Africa; four in Tanzania and one in Kenya. The two students working in Tanzania were assisted by a post-doc, Katarzyna Nowak, in Professor Andrew Dobson’s laboratory. Nowak set up a variety of contacts in Dar es Salaam and Zanzibar to enable undergraduate student Aquina Wihak ‘11 to work on malaria eradication. Undergraduate Neia Prata ‘11 spent a summer working on mapping the distribution and abundance of tsetse flies, the vectors of sleeping sickness (trypanosomiasis) in and around Serengeti National Park.

Both of these projects required the students to collate long-term data from hospital records and to combine this with their own field observations, along with creating mathematical models that include the diversity of species that either act as hosts in the life cycle, or species that modify the abundance of host species.

The student working in Kenya, Meyeneobang Inyand ’11, was based at Mpala ranch and collected data from local health clinics to examine possible interactions between HIV and malaria. She developed mathematical models to conduct this analysis as part of her senior thesis.

Claire Standley, a post-doc, examined the role of biodiversity in modifying the dynamics of schistosomiasis (snail fever) at several sites in Tanzania: Gombe Stream National Park, Mahale National Park, Rubondo Island National Park in Lake Victoria, and Serengeti National Park. Two undergraduates worked with Standley on this project. Kathleen LaRow ’12 examined how the diversity of fish that feed on snails impact the abundance of the snail species that acts as an intermediate host for schistosomiasis; the other student, Kelly Harchut ’12, studied the reliability of malaria diagnostic tests for her senior thesis.

A graduate student in Dobson’s laboratory, Christina Faust, obtained Health Challenge funds to examine the role of primates as reservoir hosts for a new emerging species of malaria in South East Asia. Faust traveled to South East Asia, collecting preliminary data and setting up field sites and collaborations in preparation for field research conducted during the summer of 2011.

Other Outcomes

During 2011, this award resulted in the development, by Professor Andrew Dobson, of a new set of theoretical models for pathogens with complex life cycles. The models provide broad and general insights into the ways in which the prevalence of vector pathogens with complex life cycles are dependent upon the abundance of both species that act as hosts at different stages in their life cycle.

In addition, this project will complement the long-term collaborations of Professor Andrew Dobson with the Tanzanian EcoHealth Project, which is a collaboration that focuses on the health of humans, domestic livestock, and wildlife in around Serengeti National Park and Gombe Stream National Park.

Future Directions:

This project ultimately intends to develop a three-week ‘Tropical health’ course for Ecology and Evolutionary Biology students attending a junior semester at Mpala Ranch in Kenya.

This award will also:

  1. help integrate the projects with ‘gap-year’ students working at the Wilson School in Arusha;
  2. provide pre-freshmen students with research experience with Princeton faculty before they enter as freshmen, and
  3. allow seniors to spend a year after graduation advancing pursue their research.


Participating Department

Collaborating Institutions




Professor of Ecology and Evolutionary Biology
Professor of Ecology and Evolutionary Biology and Public Affairs, Woodrow Wilson School

Research Associates:

  • Christiana Faust
  • Katarzyna Nowak
  • Claire Standley

Undergraduate Students:

  • Kelly Harchut ’12
  • Meyeneobang Inyand ’11
  • Kathleen LaRow ’12
  • Neia Prata ’11
  • Aquina Wihak ’11