Viewpoints
The Need for Full Integration of Snakebite Envenoming
within a Global Strategy to Combat the Neglected
Tropical Diseases: The Way Forward
Jose´ Marı´a Gutie´rrez1*, David A. Warrell2, David J. Williams3,4, Simon Jensen3,4, Nicholas Brown4,5,
Juan J. Calvete6, Robert A. Harrison7, for the Global Snakebite Initiative
1 Instituto Clodomiro Picado, Facultad de Microbiologı´a, Universidad de Costa Rica, San Jose´, Costa Rica, 2Nuffield Department of Clinical Medicine, John Radcliffe
Hospital, University of Oxford, Oxford, United Kingdom, 3 School of Medicine & Health Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea,
4Australian Venom Research Unit, Department of Pharmacology, University of Melbourne, Parkville, Victoria, Australia, 5 Royal Brisbane and Women’s Hospital, Herston,
Queensland, Australia, 6 Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Cientı´ficas (CSIC), Valencia, Spain, 7Alistair Reid Venom Research Unit,
Liverpool School of Tropical Medicine, Liverpool, United Kingdom
Snakebite envenoming constitutes a
serious medical condition that primarily
affects residents of rural communities in
Africa, Asia, Latin America, and New
Guinea [1,2]. It is an occupational,
environmental, and domestic health haz-
ard that exacerbates the already impov-
erished state of these communities [3].
Conservative estimates indicate that,
worldwide, more than 5 million people
suffer snakebite every year, leading to
25,000–125,000 deaths, while an estimat-
ed 400,000 people are left with perma-
nent disabilities [4–7]. Eight thousand
amputations are thought to be performed
annually in Africa alone [8]. However,
community-based surveys illustrate that
the actual burden of human suffering is
likely to be even greater [9,10]. Despite
this global impact, snakebite has received
little attention from the global health
community, the pharmaceutical industry,
governments, and public health advocacy
groups, and has a disappointingly low
priority in the global health research
agenda. As a consequence, the paucity
of health programs addressing snakebite
at national, regional, and global levels
allows deaths or maimings of snakebite
victims to continue. This burden of
suffering could be significantly reduced
because effective preventive and thera-
peutic resources are available, but, be-
cause of systemic neglect, they are not
delivered in many regions. There has
been progress in highlighting the neglect
of snakebite. Thus, the inclusion of
snakebite in the WHO list of Neglected
Tropical Diseases (NTDs), and the devel-
opment of initiatives by the WHO and its
regional offices [1,11] as well as by the
Global Snakebite Initiative (GSI) [6] and
other efforts at national and regional
levels, have improved the global aware-
ness of this disease. However, the impact
of these projects has been rather limited,
particularly in light of the progress made
in control of the helminthic NTDs.
Global efforts launched in the last
decade to confront NTDs have recruited
the important support of the World Health
Organization (WHO), governments, di-
verse funding agencies, and other advoca-
cy groups/foundations [12,13]. As a result,
there is a growing awareness of the
sociomedical importance of this group of
ancient human scourges. Several strategies
are being implemented to reduce the
burden of these diseases [13] within the
framework of the Millennium Develop-
ment Goals (MDGs). A significant
achievement has been the conceptualiza-
tion of NTDs as a group of health
problems that share many common de-
mographic, sociological, epidemiological,
and clinical features. Implementing inte-
grated initiatives conducted by advocates,
involving research and development, con-
trol, treatment, and attention to the needs
of affected populations, is now a primary
strategy to reduce disease burden. Regret-
tably, snakebite, despite being included in
the 2009 WHO list of NTDs, has not been
incorporated into these globally coordi-
nated efforts to reduce the impact of the
NTDs. The reasons for this omission are
diverse and are probably based upon the
perception that, because snakebite is not
an infectious disease, the strategies for its
alleviation do not fit within the strategies
used to combat the ‘‘typical’’ NTDs. This
perception is misleading, since snakebite
epitomizes the main features that charac-
terize NTDs [13]:
(1) Snakebite causes significant rates of
mortality, morbidity, disfigurement
[6], and chronic psychological sequel-
ae [14], and incurs a heavy loss of
productivity due to physical disability.
Since impoverished rural farmers are
the group at highest risk [3], snakebite
exerts a direct economic and social
impact on families and communities
and thereby significantly contributes
to the prevailing vicious cycle of
poverty and inequity.
(2) Since snakebite mainly afflicts low-
profile, rural populations that lack a
political voice, victims cannot influ-
ence regional and national adminis-
trative and political policy makers,
and their needs remain largely un-
heard and politically neglected.
(3) Snakebite does not represent a health
risk to high-income peoples and
countries. This contributes to the
negligible interest shown by govern-
ments to combat this problem with
the financial and political resources
appropriate to that task.
(4) Snakebite causes stigma and discrim-
ination, especially in people suffering
Citation: Gutie´rrez JM, Warrell DA, Williams DJ, Jensen S, Brown N, et al. (2013) The Need for Full Integration of
Snakebite Envenoming within a Global Strategy to Combat the Neglected Tropical Diseases: The Way
Forward. PLoS Negl Trop Dis 7(6): e2162. doi:10.1371/journal.pntd.0002162
Editor: Janaka de Silva, Faculty of Medicine, University of Kelaniya, Sri Lanka
Published June 13, 2013
Copyright:  2013 Gutie´rrez et al. This is an open-access article distributed under the terms of the Creative
Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium,
provided the original author and source are credited.
Funding: The preparation of this viewpoint did not receive financial support.
Competing Interests: The authors have declared that no competing interests exist.
* E-mail: jose.gutierrez@ucr.ac.cr
PLOS Neglected Tropical Diseases | www.plosntds.org 1 June 2013 | Volume 7 | Issue 6 | e2162
from venom-induced permanent phys-
ical deformity and disability, as well as
from amputations and other surgical
procedures employed in the manage-
ment of these complications [8]. This
affects working performance and
greatly limits the chances of victims’
finding jobs and leading productive
and fulfilling lives. In addition, since a
high proportion of cases occur in
children, snakebite may have profound
implications for their development,
education, and future opportunities,
blighting their entire lives.
(5) The true rates of snakebite-induced
morbidity and mortality are still
largely unknown in many regions of
the world because estimates are based
mostly on extrapolations of hospital
statistics. Recent national community-
based surveys have highlighted the
fact that the actual magnitude of this
disease is much greater than was
previously thought because many
snakebite victims never manage to
reach hospitals and therefore remain
unrecorded and invisible to the health
system [9,10]. The current estimate of
20,000 to 94,000 deaths caused by
snakebite annually [5] is therefore
bound to be an underestimate, mak-
ing the burden of mortality from
snakebite much higher than for other
NTDs [6].
(6) Snakebite has been largely omitted
from research agendas and does not
feature as a listed research priority for
any health funding agency. Despite
significant advances in the biochemi-
cal and toxicological understanding of
snake venoms, including the realiza-
tion of their potential as pharmaco-
logical agents, there are serious defi-
ciencies in our knowledge of the
epidemiological and clinical features
of snakebite envenomings in many
countries. There has also been negli-
gible funding for research to improve
the technologies for antivenom man-
ufacture—the only validated therapy
for snakebite envenoming. Likewise,
topics related to economic impacts,
public health policies, and cultural
perceptions of snakebite have failed to
attract the attention of research
groups and their funders.
(7) The tragedy of snakebite is that
effective solutions already exist but
are not being delivered in many
countries. Timely administration by
a trained practitioner of effective and
appropriate antivenoms can be ex-
pected to prevent most deaths and
sequelae resulting from these enve-
nomings. Although approved methods
for antivenom production are readily
available in the public domain, anti-
venoms are neither available nor
accessible in many regions of the
world [15].
Some distinctions between snakebite
and the other NTDs pose significant
challenges to establishing effective snake-
bite control programs. Thus, because it is
not an infectious disease, there is no
potential for elimination or eradication of
snakebites, unlike the expectation for most
other NTDs. Highly effective and logisti-
cally efficient mass vaccination or admin-
istration of antihelminthics, antibiotics,
and other interventions, such as vector
control, and provision of safe food, water,
and sanitation [13], are not applicable to
snakebite envenoming. Furthermore, un-
like the near global effectiveness of most
antihelminthics and antibiotics, snakebite
envenoming therapy is regionally specific
and this limits the implementation of
‘‘economics of scale’’ to antivenom pro-
duction.
Nevertheless, the fact that snakebite
envenoming coexists with bacterial, viral,
and parasitic NTDs in many rural settings
suggests patterns of comorbidity that are
amenable to integrated intervention.
There are several features of snakebite
control that are similar to the principal
aspects used to combat the infectious
NTDs, indicating that incorporation of
snakebite prevention, treatment, and re-
habilitation resources into the strategies to
fight NTDs would offer a great health
benefit to vulnerable communities. For
example, encouraging the wearing of
appropriate shoes, the use of a torch after
dark, sleeping under an insecticide-im-
pregnated bed net, and speeding patient
transport to medical care in remote areas
using trained volunteer motorcyclists (S.K.
Sharma, personal communication, 2011)
are all effective in reducing the incidence
of snakebite [16]. These approaches would
also reduce the burden of soil-transmitted
helminthic infections, tropical and Buruli
ulcer, podoconiosis, malaria, and kala-azar
and other vector-borne infections. Most of
the key elements of the WHO Global Plan
to Combat Neglected Tropical Diseases
2008–2015 [13] also apply to reduce the
burden of snakebite envenoming.
The Way Forward: Toward a
Globally Integrated Strategy
The global struggle to reduce the
impact of snakebite envenoming should
be based on an integrated approach
encompassing diverse interventions. The
key actions to achieve this should be
coordinated with the more general efforts
to combat NTDs, such as:
(1) Improving health information systems
to generate reliable disease-burden
data in regions of high NTD inci-
dence. These data would allow the
design of knowledge-based strategies
for effective prevention and treatment
of all the NTDs [17], including
snakebite.
(2) International research efforts dedicat-
ed to achieving a better understanding
of the biological epidemiology of the
NTDs would also serve to improve
understanding of the systematics and
venom composition of the snake
species of greatest medical impor-
tance, thereby fostering the develop-
ment of antivenoms with broader
coverage of snake species and geo-
graphical areas [18].
(3) Improving the availability and acces-
sibility of safe and effective NTD
treatments. This difficult task is being
very effectively addressed for the
helminthic NTDs but remains a
formidable challenge for many others.
In the case of snakebite treatment, it
involves the strengthening of current
manufacturing laboratories, the com-
mitment of large laboratories to
generate more effective antivenoms,
and the promotion of technology
transfer projects aimed at enabling
countries with a high burden of
snakebites to produce their own anti-
venoms. There is a self-perpetuating
cycle that has resulted in a decline in
the production of antivenoms, espe-
cially for sub-Saharan Africa. Inade-
quate financial support for antivenom
production and the poor quality of
some products has caused loss of
confidence, a reduced market, a
consequent drop in production, and
increased prices, which in turn con-
tribute to further reduction in avail-
ability and accessibility, and an alarm-
ing increase in the unscrupulous
marketing of inappropriate products
[19–21]. The net result has been a
serious crisis in the access to anti-
venoms in various regions of the
world. The solution to this problem
has to be based on: (a) the generation
of increased volumes of safe and
effective antivenoms, (b) the improve-
ment of the capacity of national
regulatory agencies to ensure the
safety and efficacy of antivenoms, (c)
PLOS Neglected Tropical Diseases | www.plosntds.org 2 June 2013 | Volume 7 | Issue 6 | e2162
the allocation of national and inter-
national resources for the regular
purchase of antivenoms, and (d) the
design of marketing and purchasing
strategies that guarantee access to
affordable antivenoms for the health
systems of developing countries. This
resolution of the snakebite problem
should go hand in hand with the
strengthening of public health sys-
tems, especially with the provision of
health services to vulnerable popula-
tions in areas of high coincidence of
all the NTDs.
(4) Ensuring that the health workforce in
areas of snakebites is appropriately
trained in the clinical management of
these diseases. Establishing and main-
taining ‘‘best clinical practice’’ educa-
tion programs for all the NTDs in
high-risk regions would improve
health outcomes significantly. In
many cases, these education packages
are already available but inadequately
distributed. Thus, the WHO has
provided regional snakebite-manage-
ment guidelines [22,23] and relevant
teaching materials for nurses and
dispensers as well as medical officers.
These activities can incorporate infor-
mation and communication technol-
ogies of various sorts in a creative
manner to maximize effectiveness.
(5) Attention and follow-up for people
suffering from physical and psycho-
logical sequelae secondary to NTDs.
Snakebite, like some of the other
NTDs, causes substantial disfigure-
ment and disability that frequently
results in chronic psychological mor-
bidity [13,24]. Given the comorbidity
and geographical coexistence of these
NTDs, there is an urgent and com-
pelling need for an integrated strate-
gy, focusing on wound healing and
psychological support, to alleviate
these physical and psychological com-
plications.
(6) Implementation of preventive and
educational campaigns to reduce the
incidence of NTDs and to promote
effective first aid intervention. Again,
these campaigns would benefit vic-
tims of all the NTDs, including
snakebite victims. The involvement
of local communities in the design
and performance of these activities is
of paramount relevance to increas-
ing the likelihood of community
compliance.
The fulfillment of these tasks demands
an integrated, interprogrammatic, and
intersectorial strategy at the global level,
involving a wide spectrum of active
protagonists, such as: (a) the medical and
scientific community, (b) technology de-
velopment groups, (c) antivenom manu-
facturers, (d) national and international
public health authorities, (e) advocacy
groups, international partners, and non-
governmental organizations working in
the public health sector, and (f) diverse
community organizations and local initia-
tives in the regions where snakebites are
frequent [15]. The implementation of this
ambitious strategy, which is being pro-
moted by the GSI (www.
snakebiteinitiative.org) and other institu-
tions and organizations, should be inte-
grated with other programs designed to
combat NTDs. To quote from the Direc-
tor-General of the WHO’s address (2007)
to the Regional Committee for Africa:
‘‘Last year, WHO launched an integrated
strategy for the management of several of
the neglected tropical diseases, all of which
disproportionately affect the poorest of the
poor in Africa. Instead of a host of
individual programs going their separate
ways, we now have a unified strategy that
simplifies drug distribution, reduces dupli-
cation, and lessens some of the demands
on health systems and staff.’’ The incor-
poration of the proposed snakebite initia-
tives within the general struggle against all
the NTDs will result in a significant and
more logistically efficient reduction of
human suffering.
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