The Gombe Ecosystem Health Project: 16 years of program evolution and lessons learned

Abstract

Infectious disease outbreaks pose a significant threat to the conservation of chimpanzees (Pan troglodytes) and all threatened nonhuman primates. Characterizing and mitigating these threats to support the sustainability and welfare of wild populations is of the highest priority. In an attempt to understand and mitigate the risk of disease for the chimpanzees of Gombe National Park, Tanzania, we initiated a long‐term health‐monitoring program in 2004. While the initial focus was to expand the ongoing behavioral research on chimpanzees to include standardized data on clinical signs of health, it soon became evident that the scope of the project would ideally include diagnostic surveillance of pathogens for all primates (including people) and domestic animals, both within and surrounding the National Park. Integration of these data, along with in‐depth post‐mortem examinations, have allowed us to establish baseline health indicators to inform outbreak response. Here, we describe the development and expansion of the Gombe Ecosystem Health project, review major findings from the research and summarize the challenges and lessons learned over the past 16 years. We also highlight future directions and present the opportunities and challenges that remain when implementing studies of ecosystem health in a complex, multispecies environment.

Mycobacterium tuberculosis sensu stricto in African Apes, What Is Its True Health Impact?

“…The wild populations of mountain gorillas in Virunga National Park (Democratic Republic of Congo [DRC]), Volcanoes National Park (Rwanda) and Bwindi Impenetrable National Park (Uganda), and chimpanzees in Gombe National Park in Tanzania and Tai National Park in Ivory Coast, have maintained systematic health monitoring programs for well over 20 years. These programs consist of veterinary health evaluations as well as mortality investigation including screening for potential infectious agents [ 44 , 45 , 46 , 47 ]. These programs have shown evidence of clinical disease caused by Mycobacterium leprae [ 48 ] and granulomatous lesions in organs caused by a MTBC organism known as M. africanum West Africa 2 or Bacillus Chimpanzee in a chimpanzee [ 14 ], however, no reports of disease caused by M. tb were found in apes screened using molecular techniques.…”

“…Due to this, it is important to continue implementing and enforcing sanitary protocols for visitors, researchers and any other personnel with potential direct contact with these species. These protocols have proven to be effective in reducing the risk of pathogen exposure in the mountain gorilla and chimpanzee habitats [ 47 , 66 ] which is likely reflected in the absence of tuberculosis reports in these species.…”

Great ape health watch: Enhancing surveillance for emerging infectious diseases in great apes

“…Further, the systematic assessment of syndromic system performance in respiratory disease outbreak detection demonstrated the value of combined daily and weekly health data collection methods in assuring accuracy and reliability (i.e., daily data) along with achieving broad population coverage (i.e., weekly health census; T. M. Wolf, Singer, et al, 2019; T. M. Wolf, Wang, et al, 2019). This assessment also contributed to the development of targeted outbreak response protocols to enhance diagnostic sampling of sick individuals and their social contacts (Lonsdorf et al, 2022, this issue).…”

“…Still in place today, this long‐term database of baseline and outbreak‐associated health data has been necessary to understand disease dynamics in the chimpanzee population (Lonsdorf et al, 2018), system performance in outbreak detection (T. Wolf et al, 2018; T. M. Wolf et al, 2019a, 2019b), and development of outbreak response protocols (Lonsdorf et al, 2022, this issue). For instance, the integration of SIVcpz surveillance and pathology data demonstrated the depletion of CD4 + T cells and AIDS‐like immunopathology, refuting long‐held assumptions that SIV was apathogenic in its natural host (Keele et al, 2009; Terio et al, 2011).…”

Primatology and one health: Two disciplines destined to come together

“…The next two articles look at One Health in chimpanzees. Lonsdorf et al (2021) review the Gombe Ecosystem Health Project and its creation and evolution over the past 16 years with the goal that their results can be applied to other field sites. Next, Sonnweber et al (2021) examine the relationship between wild male chimpanzee testosterone levels in the presence of sickness and when they are asymptomatic, with results suggesting that testosterone levels in male chimpanzees are impacted when they are sick and that this may have broad implications for the fitness of males both temporarily and longer term.…”