Connecting Global Priorities Biodiversity and Human Health

and the evolution of a more suitable habitat for
invasive alien species.
eiht of the eidene and further
researh needs
• Research to date has shown strong evidence
for the overlapping drivers of disease emergence
and biodiversity loss. Anthropogenic activities
are rapidly altering ecological and evolutionary
systems under which hosts and pathogens
operate, creating new dynamics and opportunities
for disease transmission and spread.
• Further investigation is needed around the
ecological factors (e.g. community composition,
abundance, etc.) affecting disease risks for humans
and other species in ecosystems. Disease ecology
studies can provide insight on both host and
pathogen dynamics. Understanding of disease
in an ecosystem can be best served through
One Health approaches that consider the links
between humans, animals and the environment,
thus providing a more integrated and broader
understanding of disease risks as well as
prevention and control strategies.
• Environmental impact assessments (EIAs)
provide useful tools to guide risk prevention and
mitigation. Incorporating health risks into EIA
processes can provide a more robust evaluation of
risks, including the high financial cost of potential
disease emergence and outbreaks. Disease may
also have significant impacts on ecosystems (e.g.
to wild species and their provision of ecosystem
services) in addition to human health.
3.2 One Health approach to drivers of
infectious diseases
The integral infectious disease connections
between domestic animals, humans and
ecosystems are exemplified by the highly
pathogenic avian influenza (HPAI) H5N1
panzootic. Evolving from a low-pathogenic
strain, intensive poultry production, paired with
inadequate biosecurity, enabled the emergence
and spread of H5N1 among poultry flocks,
geographies, and species, including infection
of wild birds and humans (Karesh et al. 2012)
Similarly, many neglected infectious diseases
have an animal link. For example, echinococcosis,
a zoonotic pathogen transmitted from a dog
tapeworm, causes 200 000 human cases each year,
costs an estimated US$ 2 billion in losses annually
to the global livestock industry, and infects a range
of wild species (Cardona et al. 2013; Karesh et al.
2012). These examples highlight the importance
of disease surveillance across the species spectrum
to enable early detection or early warning systems.
While in some cases disease control measures may
be harmful to biodiversity, they can also yield
benefits for wildlife. Mass vaccination of cattle
for rinderpest boosted wildebeest population
numbers after large drops attributed to rinderpest
infection. Surveillance in wildlife has subsequently
been used to monitor rinderpest circulation
(Couacy-Hymann et al. 2005). Surveillance and
reporting employing a One Health approach
may provide sentinel benefits to enable early
detection of pathogens potentially transmissible
between humans, wild species, and livestock.
This is especially important given chronic underreporting
of disease in animals, including in food
production, as well as changing ecological factors
from climate change (de Balogh et al. 2013; Pinto
et al. 2008).
In order to move from the currently reactive
response to infectious disease emergence and
spread, we must also go a step further to address
the underlying drivers of disease emergence, many
which also overlap with drivers of biodiversity loss
(FAO 2013; Karesh et al. 2012; CBD 2012). This
requires an integrated effort around ecosystems,
human, and animal health, rather than a siloed
one-species or one-discipline perspective. A One
Health or ecohealth approach that considers
the links between humans, animals (domestic
and wild), and the environment can improve
understanding of infectious disease drivers and
dynamics and move from response to prevention
measures (FAO 2013; Karesh et al. 2012). Given
the high costs of disease emergence events (for
example, the 2003 outbreak of SARS cost the
global economy an estimated US$ 30 billion) and
significant public health impacts (over one billion
cases of infectious diseases annually), both the
economic and health arguments for tackling root
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