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Ebola and bushmeat: myth and reality
Noëlle F. Kümpel, Andrew A. Cunningham, John E. Fa, Julia P.G. Jones, J. Marcus
Rowcliffe and E.J. Milner-Gulland
“Bushmeat”, or wild meat, is a term that is usually applied to the meat of any wild-caught
animal that doesn’t fall under the category of “fish”, from caterpillars to crocodiles to gorillas.
The term derives from “viande de brousse”, which originated in colonial Africa. While wild meat
has been consumed around the world for as long as humans have existed, this is still particularly
prevalent in the tropics. In particular, the forest regions of Central and West Africa have a high
level of extraction of, and dependence on, wild meat1, as alternative sources of protein are
limited and there are still some relatively intact faunas which can support high levels of offtake.
In Asia, by contrast, there is comparatively more marine fish available and wildlife populations
are depleted in many areas.2 In Latin America, domestic livestock and fish are more widely
consumed,3 although the bushmeat trade is more significant than commonly assumed.4 In the
Congo basin, high human population densities and a substantial trade of wildlife into cities have
triggered concerns about a “bushmeat crisis”. Despite objections to its African connotations,
the term bushmeat has to some extent stuck; it is used by international conventions and
increasingly to refer to wild meat on other continents.5
The recent Ebola outbreak in West Africa has triggered much, often conflicting, comment by
conservationists, wildlife health professionals and the general media regarding the links
between bushmeat and Ebola.6 In January 2015, a meeting of the UK Bushmeat Working Group
– an open forum for discussion on policy and research relating to bushmeat, funded by the UK
Department for Environment, Food and Rural Affairs7 – was convened to discuss the topic. Here
we summarise and expand on some of the points raised at the meeting, in an attempt to dispel
some common misconceptions, and recommend some key policy and research needs.
Some myths and misconceptions
The threat from Ebola: Around 60% of human diseases, and around 75% of emerging
infectious diseases, are believed to be zoonotic (i.e. derived from animals), mainly from
wildlife.8 They are transmitted via different pathways; in the case of Ebola, only through
1 Milner-Gulland, E. J., E. L. Bennett, and S. A. M. W. M. Group. 2003. Wild meat: the bigger picture. Trends in Ecology
& Evolution 18:351-357.
2Bennett, E. L., and M. Rao. 2002. Wild meat consumption in Asian tropical forests: is this a glimpse of the future for
Africa? in S. Mainka, and M. Trivedi, editors. Links between biodiversity conservation, livelihoods and food
security: the sustainable use of wild species for meat. IUCN, Gland, Switzerland and Cambridge, UK.
3 Fa, J. E., and C. A. Peres. 2001. Game vertebrate extraction in African and Neotropical forests: an intercontinental
comparison. Pages 203-241 in J. D. Reynolds, G. M. Mace, J. G. Robinson, and K. H. Redford, editors.
Conservation of exploited species. Cambridge University Press, Cambridge.
4 van Vliet, N., M. P. Quiceno-Mesa, D. Cruz-Antia, C. Morsello, C. Adams, F. Mori, B. Yagüe, S. Hernández, T. Bonilla, L.
Tellez, L. Neves de Aquino, J. Moreno, T. Schor, M. De Oliveira Princi, E. Haiden, F. Trujillo, and R. Nasi. 2014.
Bushmeat in the tri-frontier region of Brazil, Peru and Colombia: Demise or persistence?. Occasional Paper
118. Center for International Forestry Research (CIFOR), Bogor, Indonesia.
5 Ibid.
6 Pooley, S., J. E. Fa, and R. Nasi. 2015. No conservation silver lining to Ebola. Conservation Biology DOI:
10.1111/cobi.12454.
7 See www.zsl.org/ukbwg for more details
8 Cleaveland, S., D. T. Haydon, and L. Taylor. 2007. Overview of pathogen emergence: which pathogens emerge when,
where and why. Current Topics in Microbiology and Immunology 315:85-111.
direct contact with bodily fluids such as blood, sweat or saliva. Ebola has probably been
under-reported in both humans and wildlife, as its symptoms can be misdiagnosed and
it is found in areas with low diagnostic capacity. While the scale and horror of the
current Ebola outbreak has justifiably made headlines, the total human death toll from
the current outbreak will probably be under 10,000, compared with the totals
succumbing every year to better-known but less news-worthy diseases (e.g. over
500,000 malaria deaths globally per year).
The risk of Ebola from bushmeat: Bushmeat hunting and butchering is a key – though
not the only – mechanism by which human populations come into contact with
reservoirs of disease, including Ebola virus, circulating in the wild. As the Ebola virus can
remain viable in untreated carcasses for up to 3-4 days,9 there is a risk of transporting it
to bushmeat markets (although there is no evidence of this to date). However, the risk
of transmitting Ebola in bushmeat overseas to Europe or the USA is extremely low, given
the total travel time and the fact that these carcasses are usually smoked (which
probably inactivates the virus). The risk of spread to new areas lies with the movement
of infected people, not infected meat.
The role of bats: Bats have some physiological features which mean they are more
likely to transmit viruses, and not just as bushmeat. Firstly, they fly, which means they
can potentially spread a virus across large distances and also drop infected material
(semi-chewed fruit, droppings or urine) which can be picked up by other animals.
Secondly, bats are known to harbour more zoonotic pathogens per species than any
other taxon,10 without themselves succumbing to disease. It has been hypothesised
that this is due to bat pathogens adapting to their host’s cyclically high body
temperature and metabolism, which then makes them resistant to the defensive fevers
triggered in other infected taxa.11 Bats are widely eaten as bushmeat in West Africa; for
example, over 100,000 bats are traded and consumed annually in southern Ghana,12 but
there has been no recorded outbreak of Ebola in that country even though Ebola is
known to be present in bats there.13 We still have much to learn about bats and
zoonotic diseases, but a kneejerk reaction to the potential zoonotic threat posed by bats
(e.g. through culling) would be massively counterproductive, given their role in
livelihoods and their particularly substantive contribution to ecosystem services,
through pollination and seed dispersal.14
9 Leroy, E. M., P. Rouquet, P. Formenty, S. Souquière, A. Kilbourne, J. M. Froment, M. Bermejo, S. Smit, W. Karesh, R.
Swanepoel, S. R. Zaki, and P. E. Rollin. 2004. Multiple Ebola virus transmission events and rapid decline of
central African wildlife. Science 303:387 - 390.
10 Luis, A. D., D. T. S. Hayman, T. J. O’shea, P. M. Cryan, A. T. Gilbert, J. R. C. Pulliam, J. N. Mills, C. K. R. Willis, M. E.
Timonin, A. A. Cunningham, A. R. Fooks, C. E. Rupprecht, J. L. N. Wood, and C. T. Webb. 2013. A comparison of bats
and rodents as reservoirs of zoonotic viruses: Are bats special? . Proceedings of the Royal Society, B 280:2012-2753.
11 O’Shea, T. J., P. M. Cryan, A. A. Cunningham, A. R. Fooks, D. T. S. Hayman, A. D. Luis, A. J. Peel, R. K. Plowright, and J.
L. N. Wood. 2014. Bat flight and emerging zoonotic viruses. Emerging Infectious Diseases 20.
12 Kamins, A. O., O. Restif, Y. Ntiamoa-Baidu, R. Suu-Ire, D. T. S. Hayman, A. A. Cunningham, J. L. N. Wood, and J. M.
Rowcliffe. 2011. Uncovering the fruit bat bushmeat commodity chain and the true extent of fruit bat hunting in
Ghana, West Africa. Biological Conservation 144:3000-3008.
13 Hayman, D. T. S., P. Emmerich, R. Suu-Ire, A. R. Fooks, A. A. Cunningham, and J. L. N. Wood. 2010. Long-term
survival of an urban fruit bat seropositive for Ebola and Lagos Bat viruses. PLoS ONE 5:e11978.;
Hayman, D. T. S., M. Yu, G. Crameri, L.-F. Wang, R. Suu-Ire, J. L. N. Wood, and A. A. Cunningham. 2012. Ebola virus
antibodies in fruit bats, Ghana, West Africa. Emerging Infectious Diseases 18.
14 Kamins, A. O., O. Restif, Y. Ntiamoa-Baidu, R. Suu-Ire, D. T. S. Hayman, A. A. Cunningham, J. L. N. Wood, and J. M.
Rowcliffe. 2011. Uncovering the fruit bat bushmeat commodity chain and the true extent of fruit bat hunting in
Ghana, West Africa. Biological Conservation 144:3000-3008.
The role of primates: Until the latest outbreak, more great apes (gorillas and
chimpanzees) than humans were believed to have died from Ebola, and the virus is a
major conservation threat to the persistence of these threatened species.15 While
primates should not necessarily be singled-out as posing a particularly high risk of
transmitting Ebola to people (28 species from 6 mammal orders, including rodents,
carnivores and cetartiodactyls, have been linked to Ebola: J.E. Fa, unpubl. data), as they
are known to get sick with the disease, they are likely to develop high viral loads which
could threaten public health. Beyond Ebola, because humans and other primates are
closely-related, there is higher cross-transmission risk of diseases in general (e.g. simian
immunodeficiency virus (SIV) in chimpanzees and sooty mangabeys mutating into HIV in
humans). As above, the main risk is to people who butcher and handle infected animals,
especially (but not exclusively) a sick animal showing signs of disease.
The role of commercial vs subsistence hunting: A number of organisations have
suggested that one way of limiting disease transmission is to ban the commercial trade
in bushmeat, while allowing subsistence hunting. This is an approach that has been
suggested for a number of years in order to reduce unsustainable bushmeat hunting.
Studies over the last 10-15 years16 have shown that individual hunters have different
balances of commercial and subsistence use depending on their current needs and
livelihood options, and people move in and out of hunting as other opportunities arise
or are curtailed. Although trade in fresh meat to urban centres may pose a disease risk,
so too does movement of people, but the livelihood implications of limiting either of
these could be severe. Governments must consider these costs and relative risks when
setting and implementing policies.
Links to deforestation: Loss of forest to agriculture, and other forms of development,
increases human-wildlife contact and provides the potential for previously-contained
zoonotic diseases to adapt to new anthropogenic environments (e.g. zoonotic spill-over
when domestic animals are reared in recently-cleared areas and act as a bridging, or
amplifier host, as occurred with Nipah virus emergence in Malaysia). However,
increased access to intact forest (e.g. through the construction of logging roads) might
present a higher risk of spill-over events. To date, most Ebola outbreaks have occurred
in areas with high levels of forest cover, such as Democratic Republic of Congo, Republic
of Congo and Gabon, but these have been contained due to low human population
densities and their remote locations. Entry of people into forest areas, particularly for
high risk activities such as hunting, increases the risk of an infected person exporting the
disease from the forest with resultant human-to-human transmission and, hence,
outbreak detection.
The food security quandary: The population of Africa is projected to at least double by
2050, but supplies of wild protein (both bushmeat and fish) are dwindling even under
current levels of demand.17 Bushmeat is seen as a ‘luxury’ in many urban centres, but
15 Walsh, P. D., K. A. Abernethy, M. Bermejo, R. Beyers, P. de Wachter, M. Ella Akou, B. Huijbregts, D. Idiata
Mambounga, A. Kamdem Toham, A. M. Kilbourn, S. A. Lahm, S. Latour, F. Maisels, C. Mbina, Y. Mihindou, S. Ndong
Obiang, E. Ntsame Effa, M. Starkey, P. Telfer, M. Thibault, C. E. G. Tutin, L. J. T. White, and D. S. Wilkie. 2003.
Catastrophic ape decline in western equatorial Africa. Nature 422:611-614.
16 Coad, L., J. Schleicher, E. J. Milner-Gulland, T. R. Marthews, M. Starkey, A. Manica, A. Balmford, W. Mbombe, T. R.
Diop Bineni, and K. A. Abernethy. 2013. Social and ecological change over a decade in a village hunting system, central
Gabon. Conservation Biology 27:270-280.; Gill, D. J. C., J. E. Fa, J. M. Rowcliffe, and N. F. Kümpel. 2010. Drivers of
change in hunter offtake and hunting strategies in Sendje, Equatorial Guinea. Conservation Biology 26:1052–1060.
17 Fa, J. E., D. Currie, and J. Meeuwig. 2003. Bushmeat and food security in the Congo Basin: linkages between wildlife
and people's future. Environmental Conservation 30:71-78.
often this may be because it is a fresh (rather than frozen) meat, rather than because
bushmeat itself is preferred. For example, East et al.18 showed that preferences in
Equatorial Guinea were for fresh meat, including fish and bushmeat, rather than frozen
fish and frozen domestic meat. Bushmeat is not just one kind of meat; for example cane
rat is often preferred, and it is a common agricultural pest.19 Chimpanzee, on the other
hand, is not generally a preferred species.20 The challenge therefore is how to ensure
that there are sufficient quantities and diversity of acceptable protein for urban people
(domestic meat, wild meat and fish), while limiting the conversion of natural habitat to
agriculture as much as possible, better managing hunting to ensure sustainable
bushmeat supplies for rural people, and minimising contact between wildlife and
livestock to limit opportunities for disease emergence (including through holding
multiple species in live animal markets).
Recommendations to African governments to reduce the risk of transmission of Ebola from
wildlife to humans:
Publicise basic public health measures related to the use of bushmeat: Public
awareness programmes should encourage people (1) to take steps to avoid being bitten
and to wear protective clothing (ideally including latex, or similar, gloves that prevent
skin contact with animal body fluids or faeces) while hunting and butchering wildlife, (2)
to not touch or collect dead or dying animals, and (3) to ensure all bushmeat is
thoroughly cooked before eating. Properly smoked or dried carcasses also carry
minimal risk of Ebola (although could pose other disease or health risks, e.g. a high level
of carcinogen load: Chaber21, and are not always preferred). These are the simplest and
most important measures that can be taken to minimise the risks of zoonotic disease
transmission in general and to prevent another Ebola outbreak.
Consider strengthening controls on commercial trade of bats and primates for
bushmeat: This is both for conservation and public health reasons, although it is
important that these two rationales for any policy change are not confounded, as it may
risk “demonizing” these species and prompt extermination attempts. In public health
terms, these taxa are relatively high risk for zoonotic disease transmission in general
(not just Ebola) compared to other species, although this risk is still extremely low and
must not be overstated. In conservation and livelihood terms, these taxa are particularly
vulnerable to over-hunting.
Improve management of livestock farming and animal markets: This should aim to
reduce contact between livestock and wildlife to limit transmission of disease between
the two.
18 East, T., N. F. Kümpel, E. J. Milner-Gulland, and J. M. Rowcliffe. 2005. Determinants of urban bushmeat
consumption in Rio Muni, Equatorial Guinea. Biological Conservation 126:206-215.
19 Alexander, J., J. McNamara, J. M. Rowcliffe, J. Oppong, and E. J. Milner-Gulland. 2014. The role of bushmeat in a
West African agricultural landscape. Oryx:1-9.
20 Kümpel, N. F., E. J. Milner-Gulland, J. M. Rowcliffe, and G. Cowlishaw. 2008. Impact of gun-hunting on diurnal
primates in continental Equatorial Guinea. International Journal of Primatology 29:1065-1082.
21 Chaber, A. L. 2008. An analysis of the African bushmeat trade in France. MSc thesis, Royal Veterinary College and
ZSL Institute of Zoology, London.
Longer-term needs:
Modelling and predicting the risk of future outbreaks of Ebola, incorporating socio-
political factors to evaluate the risk of an outbreak becoming an epidemic. This
modelling needs to include, and be informed by, virus prevalence data of wildlife
species along with the dynamics of human-wildlife contact in a range of guises (including
bushmeat hunting), in order better to predict the changing risks of zoonotic
transmission as intact forest is entered by more people and as fresh bushmeat is
transported to urban centres.
Better understanding of the transmission dynamics of Ebola and other key zoonotic
viruses in their natural wildlife hosts in West Africa and across the continent. In the first
instance, this should include identifying which species are reservoir hosts (in which the
pathogen persists at the population level) and which are spill-over hosts (which are
intermittently infected from reservoir species but in which the pathogen does not
persist at the population level). In the case of bats, this can lead to a more informed
strategy for managing human-bat interactions in order to safeguard bat populations and
their key services, while also reducing disease transmission risks.
Better understanding of local use of bushmeat, including perceptions of disease risk
from bushmeat, and the precautions people do and don't currently take, and why.
Large-scale research into scaling up provision of alternative sources of meat and fish in
Africa, which are acceptable to consumers, while maintaining intact ecosystems such as
forests which provide important local and global ecosystem services in addition to
bushmeat. This research should include gaining a better understanding of the levels of
sustainable harvest for different bushmeat species; at the moment the lack of basic
knowledge on the distribution, abundance and biology of many bushmeat species
means that it is not possible to make specific recommendations about the potential
sustainability of bushmeat hunting in different locations and for different species.
Better understanding of the various roles of bushmeat hunting in the livelihoods of rural
people, thereby enabling interventions aimed at modifying the way that people use
bushmeat to be more appropriately designed and targeted.
Improved channels for providing appropriate advice to those implementing
interventions and disseminating information on the ground (e.g. policy-making, law
enforcement and social marketing by governments and local NGOs).
Noelle Kumpel is a Policy Programme Manager at the Zoological Society of London and
chair of UK Bushmeat Working Group (noelle.kumpel@zsl.org); A. Cunningham is
Professor of Wildlife Epidemiology and Wildlife Epidemiology Theme Leader at the ZSL
Institute of Zoology, working on bats and zoonotic diseases (a.cunningham@ioz.ac.uk);
John Fa is a Visiting Professor, Imperial College London, and Senior Associate Researcher,
CIFOR, Bogor, Indonesia, working on CIFOR’s Bushmeat Research Initiative
(jfa949@gmail.com); Julia Jones is a Senior Lecturer in Conservation Science at the
School of Environment, Natural Resources and Geography, Bangor University, working
on bushmeat issues in Madagascar (julia.jones@bangor.ac.uk). Marcus Rowcliffe is a
Research Fellow at the ZSL Institute of Zoology and Co-Director of the ZSL Bushmeat
Research Programme (marcus.rowcliffe@ioz.ac.uk); E.J. Milner-Gulland is a Professor of
Conservation Science and Director, Grand Challenges in Ecosystems and the
Environment, at Imperial College London (e.j.milner-gulland@ic.ac.uk).