Dynamic Drivers of Disease in Africa
Integrating our understandings of Trypanosomiasis, ecosystems and
wellbeing
www.driversofdisease.org
www.driversofdisease.org
Key questions
•
What kinds of ecological changes affect possible
animal-to-human disease transmission?
•
How do different uses of ecosystems bring people into
contact with possible disease risk?
•
How are these local dynamics affected by wider
changes, e.g. climate, land use, urbanisation?
•
How do different people and agencies understand and
represent these dynamics?
•
What are the implications for public health policy?
Taking a One Health approach
One Health: the collaborative effort of multiple
disciplines working locally, nationally and globally
to attain optimal health for people, animals and
the environment.
• Animal and human health experts work together with
ecologists, environmental and wildlife experts
• Integrated and strategic approach replaces a fragmented
and disease-centred approach.
• Surveillance and preparedness informed by crossdisciplinary approach
Trypanosomiasis
• Parasitic diseases of humans, wildlife and
livestock
• Mainly tsetse transmitted in Africa
Species
Sub-species
Trypanosoma
brucei
Trypanosoma
rhodesiense
Hosts
brucei Humans
Livestock
Wildlife
brucei Humans HAT
Trypanosome
gambiense
Trypanosoma brucei brucei
Trypanosoma
congolense
Diseas
e
HAT
Livestock Nagana
Wildlife
(AAT)
Livestock Nagana
Wildlife
Trypanosomiasis
• Tsetse distributions dependent on
environment
– HAT and AAT also linked to environment
– Land cover/land use significant factor
• Environmental change may destabilise
tsetse dynamics and transmission of
HAT/AAT
Drivers of Disease context
Traditional Rhodesian HAT situation (inc Zambia)
• Wildlife main reservoir
• Occasional spill over into human populations
Trypanosomiasis in Uganda
• Domestic livestock largely replaced wild animal
reservoirs of trypanosomiasis
• Large outbreaks and spread of Rhodesian HAT
Could the Ugandan situation
be replicated elsewhere?
Study problem
Luangwa Valley, Eastern Province, Zambia
• On-going environmental changes
Changing dynamics of
human, livestock, tsetse and
wildlife populations
What is the impact on
HAT and AAT?
Study area
Eastern Province, Zambia
• Tropical climate, modified by
altitude
• Dry season May - Oct
• Rainy season Nov - Apr
The people
• The Kunda people are an ethnic group of
Zambia, Zimbabwe, and Mozambique
• They speak the Chikunda/Chinyanja
language, a Bantu language in the Bantu
subfamily
• Other ethnic groups like the Chewa and
Ngoni speaking people have emigrated
into area
Research activities include:
• Household and livestock census
• Participatory approaches
• Socio-economics questionnaire
• Repeat sampling of transect (animal
sampling, HAT, malaria)
• Geostatistical model from 2006 and
current data
• Ecological niche model using HAT atlas
data
Data collection methods
• Ecological and animal population surveys
• Pathogen/antibody sampling in animal and human
populations, laboratory analysis
• Narrative interviews
• Participatory mapping, ranking, scoring
• Household surveys
• Secondary data sources – published literature,
government and health centre records, satellite data,
spatially-referenced databases
Expected scientific
outcomes/academic impact
• A novel theoretical conceptualisation of the
relationships including trade-offs between ecosystem
services, disease regulation and human wellbeing
• A new evidence base on ecological, social and political
dynamics of emergence and transmission for key wildlife
and livestock-transmitted diseases
• An integrated set of process-based, empirical and
participatory models across scales, leading to socialecological systems analysis to identify
tipping points, trade-offs and interventions;
• An understanding of the drivers of such ecosystem-
disease-wellbeing dynamics at multiple scales, feeding into
prognostic models and scenarios for use in policymaking;
• An understanding of current policy processes and the
political economy of knowledge across stakeholder
groups;
• New methods and practices of interdisciplinary and
researcher-practitioner collaboration, and built capacity
across partner organisations to apply these;
•Drivers of Disease is also geared towards practical and
policy impacts: Towards managing ecosystem services in
sustainable ways that reduce disease risks and burdens for
the poor