WSAVA Nov 2021 Proceedings - Flipbook - Page 23
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RABIES: PRACTICAL DELIVERY OF ONE HEALTH
T. Scott1, A. Coetzer2, L. Nel2
Luxembourg/Luxembourg, 2Pretoria/South Africa
1
Qualifications:
Dr. Terence Peter Scott
PhD Microbiology (Virology; Rabies)
terence.scott@rabiesalliance.org
Rabies is a deadly zoonotic disease that kills both animals and humans
equally effectively. While the majority of the focus for rabies advocacy
and elimination presently lies with the public health impact of the disease,
this does not detract from the fact that in addition to the estimated 59
000 human deaths each year, rabies also kills hundreds of thousands
of non-human mammals. Critically, rabies is entirely preventable in both
human and canine populations through mass vaccination, and the most
effective means to eliminate the disease in humans is to eliminate the
disease in dog populations in endemic countries. Not only is this possible,
but this approach has been demonstrated to be the most practicable and
economically viable. Thus, rabies is an excellent example for the practical
delivery of One Health and should be considered the ‘flagship’ disease to
demonstrate the concept.
One Health has many definitions, the majority of which remain vague and
generalized and are often biased towards the goals of the organization or
group that defined it. However, the One Health Commission has developed
a more inclusive definition for One Health as follows: “One Health is a
collaborative, multisectoral, and trans-disciplinary approach - working at
local, regional, national, and global levels - to achieve optimal health and
well-being outcomes recognizing the interconnections between people,
animals, plants and their shared environment.”1. Despite the presence of
multiple definitions, the principal aspects of One Health remain consistent
in the fact that human, animal, and environmental health are inter-dependent. This epitomizes the need for collaboration for the effective control
and elimination of rabies, whereby the three health systems (human,
animal and environmental) are critical to achieving success. For rabies,
animal health should be considered the keystone to achieving elimination,
as human health is directly and inextricably linked to animal health, and
animal health is linked to environmental health, yet human health is not
reliant upon environmental health. Therefore, the animal health sector
is crucial for the operationalization of the One Health approach for dog
rabies control and subsequent elimination.
Many countries have drastically reduced the number of human rabies
deaths to nearly zero through preventative pre-exposure prophylaxis
(PrEP) and timely and adequate treatment of exposed individuals with
post-exposure prophylaxis (PEP)2. However, these measures are solely
preventative and reactionary measures that do not address the issue at its
source, resulting in the need for expensive and continued human health
interventions in perpetuity. In contrast, many of the countries that have
controlled and eliminated both dog-mediated human rabies and dog rabies
have done so through effective mass dog vaccination strategies. While
mass dog vaccination has been demonstrated to be the most cost-effective and practical means to eliminate almost all human rabies deaths,
there remains a disparity in resource allocation and availability for the
implementation of these programs in dog-rabies endemic countries. While
veterinarians and animal health practitioners are tasked with multiple
responsibilities for rabies control and elimination, it is understood that in
general, the veterinary sector remains poorly funded and resourced. It is
for this reason that there lies the need for true One Health collaboration
between human and animal health, so that funding and resources from the
better resourced human health sector can be used to address the issue
of rabies at the source – in the dog population – rather than responding
to cases and using the allocated resources on human prophylaxis3.
While both pre- and post-exposure prophylaxis for people is essential
and should not be ignored, investment into the vaccination of dogs would
result in a significant reduction in expenditure once dog-mediated rabies
has been eliminated.
To make a case for the sharing and allocation of resources towards jointly
combatting rabies using a One Health approach, there is a clear need for
effective surveillance within each of the sectors, but also a dire need for
effective and transparent data sharing among sectors. For human health
to adequately invest in rabies elimination through mass dog vaccination,
the evidence-base is needed to identify which areas should be targeted
for dog vaccination based on bite incidents and human rabies cases.
Therefore, the human health sector needs to collect, analyze, and share
this data in a timely manner with the relevant stakeholders in the animal
health sector for reactionary interventions. Similarly, the animal health
sector must share their data to help identify areas that need attention,
helping to direct the allocation of therapeutics and biologicals to health
facilities in high-risk areas. Only through such concerted efforts can dog
rabies elimination be achieved in a timely and cost-effective manner. By
targeting hotspots and high-risk areas with strategic interventions (rather
than through a blanket approach required to achieve herd immunity in the
entire dog population), further cost-savings can be made.
While the roles of both human and animal health are critical and most
prominent for dog rabies elimination, the environmental sector is often
overlooked. While scientific studies are lacking as to the direct role of the
environment on rabies elimination, there have been suggestions as to its
importance through various factors. For instance, in dog-rabies endemic
countries, the environment has the potential to affect the size, distribution, and turnover of dog populations through the availability of food
resources and the carrying capacity of the area. With a larger carrying
capacity, a larger – typically unwanted - dog population is possible in
areas where free-roaming dogs are prominent. These free roaming dog
populations are typically more challenging to vaccinate and thus affect
the resources required to achieve herd immunity in these areas. On the
other hand, environmental factors can contribute to rabies elimination
efforts and the prevention of the re-introduction of the disease from
neighboring areas. Geographical barriers have been successfully used to
create vaccination corridors that create a buffer zone between rabies-free
areas and those that remain dog-rabies endemic4. Lastly, climate change
and the migration of reservoir species into new territories poses a risk
for the introduction of new rabies variants. This is most evident with the
northerly migration of vampire bat species from Latin America into North
America which now poses a risk of the introduction of vampire bat rabies
virus variant into the United States.
To support the efforts to operationalize One Health, rabies has the tools
and technologies available to effectively implement these concepts. The
Stepwise Approach towards Rabies Elimination (SARE) tool is integral to
the Global Strategic Plan, and both encourages and fosters One Health
collaboration through a joint landscape analysis and the development
of an inter-sectoral work plan5. Similarly, surveillance tools such as the
Rabies Epidemiological Bulletin have been designed for transparent, effective, and real-time data sharing between sectors and partners, ensuring
that effective decisions can be made towards the joint goal of eliminating
dog-mediated human rabies.
With the emphasis of the One Health approach in the Sustainable Development Goals, as well as in various recent international guidance documents
such as the WHO Neglected Tropical Diseases Roadmap, as well as the
emphasis for the need for One Health from international political leaders
at the recent G20 summit, it is essential that the global community is capable of operationalizing this concept into an effective approach. Rabies
presents as the ideal candidate disease to operationalize One Health in
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