ArticlePDF Available

Venom, antivenom production and the medically important snakes of India

Authors:
  • Centre for Herpetology/Madras Crocodile Bank Trust, India, Mahabalipuram

Abstract and Figures

Snakebite is a medically and socially significant issue in India, but the quality of treatment and reporting protocols need to be upgraded to international standards. There are currently seven pharmaceutical laboratories in India which produce antivenom against four medically important Indian snake species (cobra (Naja sp.), krait (Bungarus sp.), Russell's viper (Daboia russelii) and sawscaled viper (Echis carinatus sp.), the 'big four'. Most venom for antivenom production is sourced from Chennai, South India. While the 'big four' are responsible for a majority of serious and fatal bites, the situation is actually much more complex. In this article, we review the production of venom and antivenom in India and suggest areas of improvement. We show that several factors complicate the treatment of snakebite in India. The first is geographic, intra-species variation in venoms of cobras and Russell's vipers. Secondly, there are four species of cobra, eight species of kraits, two distinct sub-species of saw-scaled viper. In view of these observations, it is felt that identifying, evaluating and implementing changes to venom and antivenom production protocols, public education, snakebite treatment and policy in India should be an immediate priority.
Content may be subject to copyright.
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012 635
The authors are in the Centre for Herpetology/Madras Crocodile Bank,
Mamallapuram 603 104, India.
*For correspondence. (e-mail: kingcobra.two@gmail.com)
Venom, antivenom production and the
medically important snakes of India
Romulus Whitaker* and Samir Whitaker
Snakebite is a medically and socially significant issue in India, but the quality of treatment and re-
porting protocols need to be upgraded to international standards. There are currently seven phar-
maceutical laboratories in India which produce antivenom against four medically important Indian
snake species (cobra (Naja sp.), krait (Bungarus sp.), Russell’s viper (Daboia russelii) and saw-
scaled viper (Echis carinatus sp.), the ‘big four’. Most venom for antivenom production is sourced
from Chennai, South India. While the ‘big four’ are responsible for a majority of serious and fatal
bites, the situation is actually much more complex. In this article, we review the production of
venom and antivenom in India and suggest areas of improvement. We show that several factors
complicate the treatment of snakebite in India. The first is geographic, intra-species variation in
venoms of cobras and Russell’s vipers. Secondly, there are four species of cobra, eight species of
kraits, two distinct sub-species of saw-scaled viper. In view of these observations, it is felt that iden-
tifying, evaluating and implementing changes to venom and antivenom production protocols, public
education, snakebite treatment and policy in India should be an immediate priority.
Keywords: Antivenom, snakebite, snakes, venom.
‘IN January 1870, being then in Calcutta, I collected sta-
tistical information which afforded proof that the loss of
human as well as animal life in India from the bite of
venomous snakes was very great; and as it seemed to me
that this ought to be, to a great extent, preventable, I
extended my investigations with the view of obtaining
accurate information as to the characters and peculiarities
of the venomous snakes themselves, the localities in
which they most abound; the modus operandi of the poi-
son; the circumstances under which the bites are inflicted;
the value of any known remedies in the treatment of those
bitten, and what measure might possibly be devised for
diminishing this serious evil….’1
Snakebite in India has been a subject of considerable
interest and debate for centuries. During the colonial era,
several physicians and naturalists were remarkably pre-
scient in their observations and strived to alleviate the
trauma and suffering inherent in what has been identified
as a common rural occupational hazard. A study reports
19,060 human deaths from snakebite in India in 1880
(ref. 1). The author petitioned the government of the time
not to cut and clear jungles near villages, but rather to
offer rewards for killing venomous snakes and to provide
identification and information charts in colour. Alto-
gether, 467,744 snakes were killed for rewards during
1880 and 1881. This, the author asserted, resulted in
lesser human deaths (18,610) on 1881, though the
methodology for data collection is not given. It
seems likely that a majority of the snakes (if indeed ven-
omous species) brought in for rewards were saw-scaled
vipers, the only species of venomous snake in India that
occurs abundantly in several places1. The Dictionary of
the Economic Products of India (1892) states that there
were 22,480 snakebite deaths in India in 1889 and an
average of about 20,000 per year ‘for the past 10 years’
(when India had a population of about 250 million
people). The editor makes the astute observation that the
‘Death rate is higher or lower more in relation to the
habits of the people than to the prevalence of poisonous
snakes.’2
A century later, it is still acknowledged that snakebite
is a serious medical problem in rural India and in
April 2009, snakebite was added to WHO’s list of
‘neglected tropical diseases’3. A recent study reported
that worldwide, the total number of snakebites could
be as high as 5.5 million with 94,000 deaths4. Reliable
statistics for India are available only now, thanks to
the Million Death Study, an initiative of the Registrar-
General of India and the Centre for Global Health
Research at St Michael’s Hospital and University of
Toronto, Canada. Based on this study, the upper estimate
for snakebite deaths in India is a staggering 50,000 per
annum5.
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012
636
Reasons for such a high incidence of snakebite and
resultant mortality in India include the following:
High numbers of snake species of medical importance
in agricultural areas.
Inadequate distribution/availability/publicity of anti-
venom serum (AVS).
Reliance on traditional and quack treatments.
Walking at night without light, no adequate footwear,
sleeping on ground mats.
Lack of widely disseminated, standardized first aid
and treatment protocols.
Geographic variation in venom composition.
Lack of knowledge about snake habits and behaviour.
Inadequate training of clinicians in dealing with
snakebite.
Morbidity, including loss of limbs and other serious
disability could affect further hundreds of thousands of
victims of venomous snakebite, but there are no reliable
data. Inexplicably however, the Government of India’s
‘National Health Profile’ reports a total of more than
1,400 snakebite deaths for all of India6. Since 2008, the
Government of West Bengal has given Rs 1 lakh com-
pensation to families of persons killed by snakebite. In
2011/2012, the total amount disbursed was Rs 4 crores 11
lakhs, indicating a minimum of 411 snakebite deaths in
that state alone (source: West Bengal State Health Bureau).
As important as it is for accurate compilations of
snakebite data to aid our understanding and guide snake-
bite management, there is sufficient data to demonstrate
the urgent need to bring together key stakeholders: clini-
cians, venom researchers, antivenom producers, venom
producers, health authorities and wildlife authorities (all
snakes are protected in India). Some of the important
issues to address are as follows:
Reliable supply of quality snake venoms.
Reliable supply of quality, high potency antivenom
and its publicity.
Regional variation in venoms.
Regional differences regarding species responsible for
bites.
Review of snake species of medical importance.
Training in snakebite first aid and treatment.
What follows is a review of available data on the produc-
tion of snake venom and antivenom in India and the species
responsible, based on existing literature and communica-
tion with colleagues in the field. The main purpose is to
provide a guide to the current production of venom and
antivenom in India. The second purpose is to encourage
further effort in this direction so that the production of
appropriate venom and antivenom can be based on robust
science rather than heresay or mere repetition of esta-
blished, but not optimum, production protocols and
potency standards. Lastly, it is acknowledged that the
advancement in snakebite treatment with antivenom has
never been a subject of importance in training clinicians
nor has it been conveyed to the public at large. Publicity
and knowledge sharing about prevention and treatment of
snakebite at the clinical, village and rural levels is an
essential part of the national mitigation initiative that is
the need of the hour. Community education about snakes
and their habits, sensible behaviour to avoid bites such as
using a torch at night, sleeping under a mosquito net and
watching where you walk are basic requirements to
reduce what is a tremendous health burden for India.
Competition from unregistered ‘medical
practitioners’
Before the widespread usage of an effective antivenom in
the early 20th century, a plethora of ‘remedies’ were
available to victims of snakebite. Delving into the litera-
ture, it can be seen that a century ago, it was already as-
certained that none of the existing ‘cures’ had any value.
A. J. Wall who, in the footsteps of Joseph Fayrer and
others, tested many of the existing ‘remedies’ states: ‘In
regard to remedies…, it is impossible to exaggerate the
uselessness of each of them.’7
Amazingly, today it is as easily possible to go for
treatment of a life-threatening venomous snakebite to a
shaman, herbalist or other ‘healer’ in India, as it was
a hundred years ago. Traditional Indian medical systems
of ayurveda, siddha and the introduced homeopathic sys-
tem have sophisticated treatments for many ailments,
developed over time. However, antivenom, prepared by
immunizing horses or sheep is the only medically
accepted remedy for systemic snake envenomation8.
When practitioners of other medicine systems purport to
be able to treat systemic symptoms of serious venomous
snakebite, it becomes dangerous, life-threatening quackery.
Purveyors of bogus snakebite remedies have a ready
market amongst the superstitious in rural and semi-rural
communities, and there do not seem to be any effective
laws to prevent the sale and use of these ‘treatments’.
Serious envenomation or mortality occurs in less than
10% of the snakebite victims which makes the ‘quack’
appear quite successful and flourish in his trade. Figure 1
is an illustrative example of a well-known bogus ‘rem-
edy’ for snakebite available in India and used even by
educated people. Although exact numbers are not known,
several authors estimate that 20–70% of snakebite victims
go to unregistered medical practitioners (read ‘quacks’)
for treatment often resulting in tragedies8,9. A relevant
question is why the purveying of such quack ‘remedies’
is not considered a criminal offence.
Widely publicizing the efficacy of antivenom treatment
for snakebite victims will certainly improve the current
situation. In addition, clinicians with rural patients need
to familiarize themselves with the latest WHO update on
snakebite treatment protocol10 (http://www.searo.who.int/
LinkFiles/BCT_Snake_Bite_Guidelines.pdf) and the
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012 637
snakes of medical importance in their area. Efforts
towards community education and promoting sensible
activity and awareness of snake movement and
habits amongst farmers and their families are of utmost
importance.
Venom production
In India, all snakes are protected under the Wildlife Pro-
tection Act and as such, snakes cannot be collected or
venom extracted without the permission of the state wild-
life authorities11. There is no scientific study that ade-
quately quantifies snake abundance (though the export of
up to 10 million snake skins per year in the 1960s gives
some indication), which has resulted in a conservative
stance by the wildlife authorities in some states and a
general reluctance to permit capture of large numbers of
snakes for venom extraction to produce AVS.
Case study A – the Irula Snake Catchers Industrial
Cooperative Society
The Irula Snake Catchers Industrial Cooperative Society
(ISCICS), which operates in two districts of Tamil Nadu
totalling 7,850 sq. km, is a tribal self-help project set up
in 1978 (ref. 12). The Society is licensed by the Tamil
Nadu Forest Department to capture an average of 8,000
snakes per year of the four most medically important spe-
cies, the ‘big four’. Snakes are kept in captivity for 3–4
weeks and venom extracted four times from each snake.
Snakes are then released back to the wild. Table 1 gives
the average annual sales made by the society for the
period 2000–2009 for antivenom production.
The number of snakes permitted to be caught under the
state forest department license determines the relative
Figure 1. The infamous ‘snake stone’ from a clinic in Kerala, India.
quantities of venom produced. This has resulted in a per-
ennial surfeit of cobra and Russell’s viper venom, hence
the Irula Cooperative stipulates that buyers must purchase
venom in a ratio of 5 : 5 : 1 : 1 (Naja : Daboia : Bungarus :
Echis). For buyers who wish to purchase only krait
or saw-scaled viper venom, the price is an astronomical
US$ 3888 per gram13. Antivenom producers have
expressed concern over the high venom prices (see Table
2) and purchase of Irula Cooperative venoms dropped
considerably in 2010 (ref. 14). New methods of immuni-
zation require much less venom to produce the same re-
sults which will of course reduce demand even further8.
In comparison, prices for Indian snake venoms produced
in the USA are US$ 150 per gram for spectacled cobra,
US$ 600 for Russell’s viper and US$ 400 for saw-scaled
viper (Kentucky Reptile Zoo).
The Irula Cooperative now produces a major portion
(an estimated 80%) of India’s venom needs (for the pro-
duction of antivenom) from snakes found within two
districts of Tamil Nadu14. Therefore, it would be advan-
tageous to expand the scope of the cooperative activities
to other parts of the country by becoming a multi-state
cooperative in order to include other snake catching
communities under its wing. This will benefit both mar-
ginalized snake catchers as well as being a big step
forward in dealing with the complex and life-threatening
problem of regional venom variation and address the pos-
sibility of other species of snakes being medically impor-
tant. However, it is to be noted that the standards of
venom production and protocols of the cooperative have
considerable scope for improvement in conformity with
WHO guidelines8.
Case study B – N.S. and Associates, Sehore,
Madhya Pradesh
This is a small venom production unit started in 2004,
with the capacity to keep 100 to 150 snakes. The snakes
Table 1. ISCICS venom sales (average annual sales
for 10 years, 2000–2009)
Species Quantity (grams)14
Naja naja 274
Bungarus caeruleus 38
Daboia russelii 262
Echis carinatus 36
Table 2. ISCICS venom prices per gram (lyophilized) (July 2010)
Species Price per gram (US$)13
Naja naja (spectacled cobra) 511
Bungarus caeruleus (common krait) 888
Daboia russelii (Russell’s viper) 666
Echis carinatus (saw-scaled viper) 1,000
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012
638
(only Naja naja and Daboia russelii) are caught locally in
houses and gardens in response to villagers’ requests. Till
2008, a total of 295 ml of N. naja and 51 ml of D. russelii
liquid venom had been sold to an antivenom manufac-
turer15.
There are several other producers of snake venom
in India, but the status of their legality is questionable
and some reportedly supply liquid or ‘light-bulb dried’
venom to antivenom producers. The WHO protocol for
venom standards and production for the manufacture of
antivenom is unfortunately, not yet implemented in
India. In 2009, the Maharashtra State Forest Department
announced plans, via a press release, to set up a Snake
Venom Research and Extraction Centre in Nashik, utilizing
the snakes caught by ‘snake rescuers’, often attached to
local animal welfare bodies16. The current status of this
initiative is unknown, but considering the popularity of
snake rescue in many parts of India, this is an obvious
potential source of snakes for venom production.
Production of antivenom
In an effort to quantify total antivenom production capa-
city in India, along with projected production estimates of
Indian antivenom producers, a simple questionnaire was
sent, via e-mail, to all these producers, with follow-up
phone calls required for most respondents. There are cur-
rently at least seven laboratories in India which produce
snake antivenom; Table 3 shows their stated projected
production estimates for 2011/2012.
Antivenom production statistics from the Indian Cen-
tral Bureau of Health Intelligence (ICBHI) for the years
2008–2009 are shown in Table 4 (ref. 17). These statis-
tics when compared with the results of the author-
conducted survey, suggest that installed capacity for the
production of AVS has increased by at least 260% over a
period of 3 years. This figure, however, does not accu-
rately quantify the actual situation, as data is missing
from both the data sets. This further illustrates the need
for a standardized, data collection, collation and display
system to process all data related to the production and
use of antivenom.
Earlier production estimates (2001–2004) are also pub-
lished by ICBHI18. These figures, as originally published,
are somewhat difficult to interpret as different units have
been used, sometimes within individual data sets. For
ease of representation, they have all been converted into
the same units and are presented in this paper as thou-
sands of vials (10 ml vials are standard antivenom doses
in India) as in Table 5.
The installed production capacity of antivenom pro-
ducers in India appears to have dropped by nearly 300%
from 2001 to 2008; following this, there has been an
increase of at least 260% in installed capacities from 2009
to 2011. Reasons for the decline include the fact that the
Serum Institute of India, one of the biggest producers,
stopped production for many years. The subsequent in-
crease in production from 2009 to 2011 could be ex-
plained by several factors, including the emergence of
new producers (for e.g., Mediclone Biotech, Chennai),
and an increase in production capacity by others – most
notably Bharat Serums and Vaccines, whose installed ca-
pacity increased almost four-fold from 400,000 vials in
2001, to 1,500,000 vials in 2010.
Two antivenom producers have recently stopped pro-
duction.
Serum Institute of India, Pune Polyvalent for ‘big
four’, lyophilized, average annual production >100,000
vials. Also lyophilized polyvalent for two species of
African snakes combined (for reasons unknown) with
Indian Daboia and Echis. Production of antivenom
was stopped in 2008, reportedly in view of the strin-
gent conditions which were implemented by the
Committee for the Purpose of Control and Supervi-
sion of Experiments on Animals (India) CPCSEA.
Venom source (India): Irula Cooperative.
Central Research Institute, Kasauli (Government
of India) Polyvalent for ‘big four’, lyophilized, aver-
age annual production was 25,000 vials. Production dis-
continued on 2007. Venom source: Irula Cooperative.
All Indian antivenom labs produce polyvalent serum of
equine origin against the four most common and widely
distributed medically important Indian snake species,
referred to for brevity as the ‘big four’. It has been
observed that 2010 prices for a 10 ml vial of Indian poly-
valent AVS range from about INR 300 to 500 (US$ 6.50–
11.00), which is a fraction of the cost of a vial of CroFab
antivenom in the USA (at over US$ 1900 per vial) or
CSL antivenom in Australia (at US$ 1500 per vial)15,19,20.
Table 3. 2010–2011 production estimates of Indian polyvalent
antivenom (responses from an author-conducted survey)
Production estimates
Institute (10 ml vials)
Public sector
Central Research Institute, Kasauli 0
Haffkine Institute, Mumbai 180,000
King Institute, Chennai 3,300
Bengal Chemicals and
Pharmaceuticals Ltd, Kolkata NR
Private sector
Serum Institute of India, Pune 0
VINS Bioproducts Ltd, Hyderabad No projection
Biological E Ltd, Hyderabad 200,000
Bharat Serum and Vaccine, Mumbai 1,500,000
Mediclone Biotech (Chennai) 75,000
Total 1,958,000
NR, Not received.
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012 639
Table 4. Production values of Indian polyvalent antivenom serum for 2007–08 and 2008–09
Actual production
Institute Installed capacity (10 ml vials) 2007–08 2008–09
Public sector
Central Research Institute, Kasauli 30,000 2,500 0
Haffkine Institute, Mumbai 393,000 1,600 396,500
King Institute, Chennai 75,000 0 0
Bengal Chemicals and 6,000 400 NR
Pharmaceuticals Ltd, Kolkata
Private sector
Serum Institute of India, Pune 40,000 NR NR
VINS Bioproducts Ltd, Hyderabad 30,000 NR NR
Bharat Serum and Vaccine Pvt Ltd, Mumbai 84,000 NR NR
Biological E Ltd, Hyderabad 20,000 NR 11,700
Total 678,000 4,500 408,200
NR, Not received.
Table 5. Actual production values of Indian polyvalent antivenom serum for 2001–02 and 2002–03, proposed production
for 2003–04 (1000s of vials)
Actual production Proposed production
Installed capacity
Institute (10 ml vials) 2001–02 2002–03 2003–04
Public sector
CRI, Kasauli 35 70.9 26.4 36
HBPCL, Bombay 453 143.1 143.3 250
KIPM, Chennai 75 4.3 0 20
Bengal Chemicals and Pharmaceuticals Ltd, Kolkata 623 231.9 NR NR
Private sector
SII, Pune 550 110.4 NR NR
VINS Bioproducts Ltd, Hyderabad 25 10.4 25 50
Biological E Ltd, Hyderabad 100 0 34 30
Bharat Serum and Vaccine Pvt Ltd 400 226.9 419.4 876
Total 2,261 797.9 648.1 1262
AVS is supplied by Indian antivenom producers to gov-
ernment hospitals at Rs 115 per vial (US$ 2.50)15. Some
labs produce both liquid and lyophilized sera and some
have produced bivalent sera in the past. While this rela-
tively low cost makes Indian antivenom more accessible,
it does have certain inherent problems, which are dealt
with under a separate heading below.
Venom and antivenom requirements for India
It will be advantageous to ascertain exactly how much
venom is required to produce an adequate quantity of
antivenom for India in order that venom supply permits
and protocols can be worked out. Based on a production
breakdown provided by an antivenom producer (though
subject to considerable variability depending on the
immunization procedures used and other factors), produc-
tion of 10,000 vials of antivenom requires approximately
2 g each of N. naja and D. russelii venom and 0.2 g each
of Bungarus caeruleus and Echis carinatus venom21.
Production of 2,000,000 vials (estimated output for
2011/2012 based on responses from antivenom produc-
ers) would therefore require an annual production of at
least 400 g each of N. naja and D. russelii venom and 40 g
each of B. caeruleus and E. carinatus venom (see the
next section).
Using these estimates, it is inferred that the Irula
Cooperative supplies only about half of India’s N. naja
and D. russelii venom requirements, but almost all of its
B. caeruleus and E. carinatus venom requirements. How-
ever, it must be noted that there was considerable vari-
ability in estimates provided by two other antivenom
producers: the second data set indicates that the produc-
tion of 2,000,000 vials would require 2,260 g of N. naja,
1,508 g of D. russelii and 300 g each of E. carinatus and
B. caeruleus venoms22. The third dataset indicates that
the production of 2,000,000 vials of antivenom would re-
quire 250 g of N. naja and D. russelii venom with 76 g
each of B. caeruleus and E. carinatus venom23. Efforts to
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012
640
Table 6. Number of snakes required to meet 2011/2012 antivenom production requirements,
(two million vials) using AVS statistics from Bharat Serums and Vaccines21
Venom yield (g) Total grams Total snakes
Species per snake (average) required (g)21 required*
Naja naja 0.330 400 1,212
Bungarus caeruleus 0.0227 40 1,762
Daboia russelii 0.200 400 2,000
Echis carinatus 0.00625 40 6,400
Total 880 11,374
*Total snakes required = total venom required (g)/average venom yield (g).
Table 7. Number of snakes required to meet 2011/2012 antivenom production requirements,
(two million vials) using AVS statistics from Haffkine Institute22
Venom yield (g) Total grams Total snakes
Species per snake (average) required (g)22 required*
Naja naja 0.330 2,260 6,848
Bungarus caeruleus 0.0227 300 13,215
Daboia russelii 0.200 1,508 7,540
Echis carinatus 0.00625 300 48,000
Total 4,368 75,603
*Total snakes required = total venom required (g)/average venom yield (g).
trace the rest of the venom supply in India have yielded
minimal information. A recent, state by state estimate of
AVS requirements in India totals 1,200,500 vials24. Fur-
ther refinement of the estimated needs will help both
venom and antivenom producers fulfil India’s actual re-
quirements.
ICBHI estimates antivenom ‘demand’ (it is unclear as
to whether this can be equated to ‘requirements’) for In-
dia to be just 110,000 doses for 2007–08 and 128,133
doses for 2008–09 (ref. 17). This is an entire order of
magnitude lower than the estimates made by antivenom
producers. We see the need, again, based on these fig-
ures, for standard methods of reporting production, de-
mand (requirements) and supply details for all antivenom
producers and purchasers.
Are our antivenom producers up to date?
Indian antivenom producers have to upgrade their pro-
duction protocols that have not changed much since the
1950s. For example, an Australian antivenom producer
uses 2 mg of taipan (Oxyuranus scutellatus) venom
to yield the equivalent of 1,600 10 ml vials of antivenom
from horses. This means that 2 million vials could be
produced by their methodology using a mere 2.5 g of
venom!
Irula Cooperative statistics13 using their standard aver-
age of four venom extractions from each snake while it is
in captivity for 3–4 weeks, have been compared to
antivenom production statistics of two producers. Tables
6 and 7 show the approximate number of snakes required
to produce 1 g of venom (lower estimate of all three
antivenom production data sets).
Table 6 provides the most conservative output in terms
of the number of snakes required to meet the antivenom
production requirements for India. Conversely, Table 7
shows a much greater estimate of the number of snakes
required – it is not possible, with the existing information
to determine which data set is most accurate, but it is
possible that an average of the two outputs provides a
reasonable overview of the situation.
Tables 6 and 7 illustrate the need for accurate report-
ing, and also the potential variability between antibody
yield and venom requirement in the production of
antivenom. All snakes are protected under India’s Wild-
life Protection Act and permits for snake capture for the
essential purpose of antivenom production, have in the
past been difficult to obtain. The process urgently needs
to be streamlined by the state forest departments11.
Issues related to Indian antivenoms
Several studies have demonstrated regional variation in
D. russelii venom. A study shows that D. russelii venom
from northern and western parts of India was twice as
toxic as venom samples from the south25. Antivenom
prepared from venum from south India failed to protect
experimental animals against venom from D. russelii of
other parts of India26. Similarly, N. naja venom from the
eastern part of India was more lethal than that of western
and northern forms and available antivenom (made
mainly with venom sourced from the south) could not
neutralize venoms from the eastern and northern parts of
the country27. Other studies showed significant variation
in the composition of D. russelii and N. naja venoms28–30.
Inadequate attention to these long-understood geo-
graphic variations in venoms is one of the reasons for the
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012 641
increasingly common reports from clinicians about the
ineffectiveness of commercially available antivenoms31–33.
Other issues include the sourcing of venom from unli-
censed producers, misleading/outdated medical informa-
tion in the instruction leaflets, noncompliance with WHO
standards and protocols for venom and antivenom pro-
duction. The export/sale of India-specific antivenoms to
other countries including Cambodia, Nigeria and Papua
New Guinea is another serious issue raised in various
national and international fora regarding antivenom pro-
duction in India34,35.
The quality and potency of South Asian antivenoms
have been largely unchanged for more than 55 years36. A
review of the situation35 highlights the fact that poor
manufacturing standards persist, and products have
minimal efficacy and unacceptably high adverse reaction
rates37. There is, therefore, an urgent need for regional
partners to come together, perhaps with external collabo-
ration, to develop a robust, potent, high quality pan-Asian
polyvalent antivenom that provides broad coverage
against the venoms of the major venomous species
throughout the region. The WHO has recently published
Guidelines for the Production, Regulation and Control of
Snake Antivenom Immunoglobulins, and produced a com-
plementary website with a number of resources8,10. As
one author puts it, ‘a new antivenom for South Asia that
meets these rigorous standards, could fulfil the needs of
all governments across the region, and at the same time
significantly improve patient outcomes, while substan-
tially reducing treatment costs35’.
The current antivenom potency requirements (set
by Indian Government regulators in the 1950s) of 0.45–
0.6 mg/ml are woefully inadequate, given the venom
yields of most of the species responsible for envenom-
ing35. While it is true that India produces the cheapest
antivenom in the world (averaging US$ 10 per vial,
retail), simple calculation shows that treatment can actu-
ally be very expensive. For example, the range of venom
yields for cobras reported in one study was 58–742 mg
(ref. 38), which translates to a need for 13–165 vials (a
treatment cost of US$ 130–1,650 or INR 6,500–82,500).
To corroborate this, one study in northern India reported
the median number of vials used for bites by elapid
snakes (kraits and cobras) as 90, for a treatment cost of
US$ 900 or INR 45,000 (ref. 39). As venom yields
measured during venom extraction may far exceed the
average (but always unknown) quantity of venom
Table 8. Venom yields of some medically important species42
Species Average venom yield (mg)
Naja naja (black form) 198.6
Bungarus sindanus 13.0
Trimeresurus malabaricus 16.5
Echis carinatus sochureki 51.2
Peltopelor macrolepis 5.1
injected in a defensive bite, it is obviously vital that
antivenom potency must be adequate (and affordable) for
a ‘worst case’ scenario.
In addition to this disparity in venom yields, variations
in venom composition and yield geographically and with
sub-species of the ‘big four’ are understudied phenomena,
which have significant implications for snakebite treat-
ment. There are at least four medically significant species
of Bungarus (kraits), viz. B. caerulus, B. sindanus, B. ni-
ger and B. walli40,41, two of Naja sps., viz. N. kouthia and
N. oxiana and one sub-species of Echis, E. carinatus
sochureki37. We are currently looking at structural differ-
ences between these venoms and aim to determine ED50
(effective neutralizing dose of antivenom) of Indian
antivenom against these and other species of possible
medical significance42. Table 8 illustrates venom yields
from the first extractions conducted by the Centre for Her-
petology as part of a collaborative effort to quantify struc-
tural differences in venom composition geographically.
These average venom yields indicate that, although
antivenom is not made specifically for these species/
variants, all of them (with the exception of P. macrolepis
and T. malabaricus, for which there are no recorded fata-
lities) can inject potentially lethal quantities of venom.
Discussion
Snake venom production for antivenom in India was done
solely by the Haffkine Institute in Mumbai prior to the
establishment of ISCICS outside Chennai12. There are
currently seven laboratories producing antivenom in India
with a total production capacity estimated at two million,
10 ml vials15,22–24. Based solely on venom sales by the
Irula Cooperative, requirements to fulfil this capacity are
approximately 1,330 g each of N. naja and D. russelii and
133 g each of B. caeruleus and E. carinatus. However,
these figures are subject to confirmation and require-
ments based on data from antivenom producers are sig-
nificantly different. One data set indicates a requirement
of about 2,260 g of N. naja, 1,508 g of D. russelii and
300 g each of E. carinatus and B. caeruleus22.
The current potency of Indian antivenoms is 0.60 mg/
ml for cobra, while prior to the 1950s, it was 4 mg/ml. In
Russell’s viper venom, it was 2 mg/ml and is now a mere
0.45 mg/ml. When and why was this changed by the
government antivenom potency regulators? This issue of
antivenom potency needs urgent attention.
Since the start of antivenom production in India over
100 years ago, conventional wisdom was that the ‘big
four’ are responsible for the majority of serious bites.
While this is still true at the generic level, current taxo-
nomy now recognizes four species of cobras, eight spe-
cies of kraits, one species of Russell’s viper and two sub-
species of saw-scaled vipers43. Also, considerable regional
variation has been found in Russell’s viper venom which
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012
642
requires further study25,26. There are growing indications
from clinicians that antivenom produced from venoms of
the ‘big four’, mainly sourced from Irula Cooperative,
may not effectively neutralize envenomation by the ‘big
four’ and related species in other parts of the coun-
try27,31,33,35. Whether this is due to venom variation, bites
by other species, low antivenom potency or a combina-
tion of these factors, needs to be determined.
In addition, several of the 22 species of pit vipers in
India43, a number of sea snakes and species such as the
king cobra are capable of causing human and livestock
disability and death. Though serious bites from most of
these species are thought to be rare, snakebites which occur
in more remote areas are often not reported. When bites
occur from species other than the four used in India’s
polyvalent antivenom production, clinicians are apt to use
the available antivenom, even though there is a great like-
lihood that it is ineffectual. For example, a recent case of
pit viper bite in the Himalayas was treated at a military
hospital using 30 ampoules of polyvalent serum, which
has no neutralizing effect on pit viper bites44.
Snakebite is responsible for tens of thousands of deaths
and disabilities every year in India3–5,35,37. In a somewhat
complex ‘snakes-of-medical-importance’ scenario, there
is an urgent need to address the following issues to
improve the situation.
Venom/antivenom research to establish venom toxi-
city, antivenom potency, minimum effective dose of
antivenoms, cross-reactivity of antivenom among spe-
cies and the important area of geographic variation of
venoms.
Venom production in sufficient quantities and to sup-
ply the demand, under WHO protocol to produce a
high standard of venom with immediate attention to
proven and likely geographic variations.
To achieve the previous point it is suggested that
India’s largest venom producer, the ISCICS be recon-
stituted as a multi-state cooperative under the central
government so that snake venom for the production of
antivenom can be collected from as wide a geographic
area as possible in recognition of the fact that there is
considerable regional variation in the composition of
venoms and that there are species other than the ‘big
four’ responsible for serious bites.
Field studies on the distribution and abundance of the
medically important snakes to guide antivenom manu-
facture (regionally specific, monovalent, bivalent,
polyvalent) and effects on local populations, if any,
on capture of large numbers for antivenom produc-
tion.
Designing a protocol acceptable to wildlife authorities
for the capture of sufficient numbers of snakes for
India’s antivenom needs, safety standards for
venom extraction and humane treatment of captured
snakes.
Education and awareness campaign to publicize use
and effectiveness of antivenom as opposed to local,
quack remedies.
Enforcement of stringent laws against bogus snakebite
‘treatments’ and appropriate public awareness against
these practices.
Inducing state and central government health agencies
to ensure wider availability of antivenom on a sub-
sidized/free distribution basis for the rural poor via
primary health centres and other rural health facilities.
Antivenom production to supply India’s needs under
WHO protocol including additional species if venom
research and clinical data proves their medical signifi-
cance. Producing a pan-Asian antivenom a high po-
tency antivenom designed for several countries across
the South Asian region, produced in large volumes
and dispensed in single dose vials is a worthy goal.
Training of clinicians in correct treatment and man-
agement of serious snakebites.
To effectively implement these strategies, it has been
suggested to the Ministry of Health, Government of India
that it convenes a series of regional and central meetings
of the key stakeholders including the following
Venom producers
Venom researchers
Antivenom producers
Clinicians with snakebite experience
State and central health authorities
Environment/wildlife authorities
WHO experts
Herpetologists with local experience.
Finally, it is significant to note that despite efforts over a
period of nearly 10 years, we have been unable to eluci-
date concrete information about any other venom produc-
tion units in India. There is ample evidence to suggest
that several other venom producers do exist, and several
individuals involved in the production of antivenom have
confirmed this. These venom producers are most likely
illegal, as suggested by paucity of information concerning
them and by their temporary nature. If mechanisms are
complimented to better facilitate, and also regulate the
creation of venom production facilities, it would go a
long way in promoting the production of high quality
venoms (following WHO protocol) and creating better
systems of accountability and reporting.
1. Fayrer, J., Destruction of life in India by poisonous snakes.
Nature, 1883, 27, 205–208.
2. Watt, G., A Dictionary of the Economic Products of India, Cosmo
Publications, Delhi, 1892, vol. VI.
3. Harrison, R. A., Hargreaves, A., Wagstaff, S. C., Faragher, B. and
Lalloo, D. G., Snake envenoming: a disease of poverty. PLoS
Negl. Trop. Dis., 2009, 3; http://www.e569; doi:10.1371/journal.
pntd.0000569.
GENERAL ARTICLE
CURRENT SCIENCE, VOL. 103, NO. 6, 25 SEPTEMBER 2012 643
4. Kasturiratne, A., Wickremasinghe, A. R., de Silva, N., Gunawar-
dena, N. K. and Pathmeswaran, A., The global burden of snake-
bite: a literature analysis and modelling based on regional
estimates of envenoming and deaths. PLoS Med., 2008, 5, e218;
doi:10.1371/journal.pmed.0050218.
5. Mohapatra, B. et al., Snakebite mortality in India: a nationally
representative mortality survey of 1.1 million homes; for the Million
Death Study Collaborators, PLoS. Negl. Trop. Dis., 2010; http://
www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.pnt
d.0001018
6. Government of India (2006, 2007, 2008, 2009), National Health
Profile of India, Central 147 Bureau of Health Intelligence, New
Delhi, 2008, pp. 107–108; http://www.cbhidghs.nic.in/index1.asp?
linkid=267
7. Wall, A. J., Indian Snake Poisons, Their Nature and Effects, Agro-
Biological Publications, Delhi (1990 reprint), 1883, p. 171.
8. WHO, Guidelines for the Production, Control and Regulation of
Snake Antivenom Immunoglobulins, WHO Technical Report
Series, October 2008.
9. Fox, S., Rathuwithana, A. C., Kasturiratne, A., Lalloo, D. G. and
de Silva, H. J., Underestimation of snakebite mortality by hospital
statistics in the Monaragala District of Sri Lanka. Trans. R. Soc.
Trop. Med. Hyg., 2006, 100, 693–695.
10. Warrell, D. A., Guidelines for the Management of Snake-bites,
World Health Organization South-East Asia Regional Office, New
Delhi, 2010, p. 152; http://www.searo.who.int/LinkFiles/BCT_
Snake_Bite_Guidelines.pdf
11. Indian Wildlife (Protection) Act (1972), Government of India,
Amended up to 2008; envfor.nic.in/legis/wildlife/wildlife1.html
12. Whitaker, R. and Andrews, H., The Irula Venom Centre – India.
In Indian Wildlife Resources, Ecology and Development (ed.
Sharma, B. D.), 1999.
13. ISCICS, Venom Price List for July 2010. Compiled and released
by the Special Officer-in-Charge, 2010.
14. ISCICS, Internal Venom Extraction and Sales Records of the Irula
Snake Catchers Industrial Cooperative Society for the year 2010,
Audited by the Government of Tamil Nadu Industrial Board, 2010.
15. N. S. and Associates, Personal communication between Romulus
Whitaker and Director of N.S & A, Sehore, Madhya Pradesh,
India on 20 March 2008.
16. Maharasthra State Forest Department, Press release, published by
Mid Day, 2009; http://www.mid-day.com/news/2009/jul/300709-
Venom-bank-Nashik-Andhashraddha-Nirmulan-Samiti-Snake-Fri-
ends-Pune-news.htm
17. Central Bureau of Health Intelligence, Government of India.
National Health Profile of India, 2009 – Health Infrastructure, 2009,
pp. 174–175; http://cbhidghs.nic.in/writereaddata/linkimages/11%-
20Health%20Infrastructure8356493923.pdf
18. Central Bureau of Health Intelligence, Government of India,
Installed capacity and production of vaccines, 2001–02 to 2003–
04, 2004; http://cbhidghs.nic.in/hia/12.03.htm
19. Antivenin (Crotalidae) Polyvalent, equine origin product informa-
tion. (MS/Antiven.001/r2-2-00), Wyeth-Ayerst Laboratories,
Philadelphia, 2010.
20. Crotalidae Polyvalent Immune FAb (Ovine), CroFab, Product
information. Protherics, Inc. Nashville, 2010.
21. Bharat Serums and Vaccines, Response to Survey on Antivenom
Production Statistics, via e-mail dated 3 February 2010.
22. Haffkine Bio-Pharmaceutical Corporation Ltd, Response to
Survey on Antivenom Production Statistics, via letter dated 30
December 2009, ref. No.: ATS/1306.
23. Mediclone Biotech Pvt Ltd, Response to Survey on Antivenom
Production Statistics, via letter dated 18 January 2010. ref. No.:
MBPL/ASVS-1/10.
24. Nair, A., Personal communication between author (Romulus
Whitaker) and Ajit Nair, VINS Bioproducts Hyderbad, India in
March 2010.
25. Jayanthi, G. P. and Gowda, T. V., Geographical variation in India
in the composition and lethal potency of Russell’s viper (Vipera
russelii) venom. Toxicon, 1988, 26, 257–264.
26. Prasad, N. B., Uma, B., Bhatt, S. K. and Gowda, V. T., Compara-
tive characterization of Russell’s viper (Daboia/Vipera russelii)
venoms from different regions of the Indian peninsula. Biochim.
Biophys. Acta, 1999, 1428, 121–136.
27. Shashidharamurthy, R. and Kemparaju, K., Region-specific neu-
tralization of Indian cobra (Naja naja) venom by polyclonal anti-
body raised against the eastern regional venom: a comparative
study of the venoms from three different geographical distribu-
tions. Int. Immunopharmacol., 2007, 7, 61–69.
28. Kasturi, S. and Gowda, T. V., Analysis of Vipera russelii venom
using polyclonal antibodies prepared against its purified toxic
phospholipase A2 VRV PL-V. Biochem. Int., 1992, 27, 155–164.
29. Mukherjee, A. K. and Maity, C. R., The composition of Naja naja
venom samples from three districts of West Bengal, India. Comp.
Biochem. Physiol. A Mol. Integr. Physiol., 1998, 119, 621–627.
30. Warrell, D. A., Snake venoms in science and clinical medicine. 1.
Russell’s viper: biology, venom and treatment of bites. Trans. R.
Soc. Trop. Med. Hyg., 1989, 83, 732–740.
31. Chippaux, J. P., Williams, V. and White, J., Snake venom vari-
ability: methods of study, results and interpretation. Toxicon,
1991, 29, 1279–1303.
32. Warrell, D. A., Geographical and intraspecies variation in the
clinical manifestations of envenoming by snakes. In Venomous
Snakes. Ecology, Evolution and Snakebite (eds Thorpe, R. S., Wuster,
W. and Malhotra, A.), Clarendon Press, Oxford, 1997, pp. 189–203.
33. Kumar, A. V. M. and Gowda, T. V., Novel non-enzymatic toxic pep-
tide of Daboia russelii (Eastern region) venom renders commercial
polyvalent antivenom ineffective. Toxicon, 2006, 47, 398–408.
34. Warrell, D. A., Unscrupulous marketing of snake bite antivenoms
in Africa and Papua New Guinea: choosing the right product
‘What’s in a name?’. Trans. R. Soc. Trop. Med. Hyg., 2008, 102,
397–399.
35. Williams, D. J., Snake bite in South Asia: a call for coordinated
action. Editorial for the global snakebite initiative. J. Ind. Soc.
Toxicol., 2010, 16, 1–3.
36. Grasset, E., Survey of assay methods of antivenins: immunologi-
cal factors influencing antivenin standardization. Bull. WHO,
1957, 16, 79–122.
37. Alirol, E., Sharma, S. K., Bawaskar, H. S., Kuch, U. and Chap-
puis, F., Snake bite in South Asia: a review. PLoS Negl. Trop.
Dis., 2010, 4, e603; doi:10.1371/journal.pntd.0000603.
38. Mirtschin, P. J. et al., Venom yields from Australian and some
other species of snakes. Ecotoxicology, 2006, 15, 531–538.
39. Agarwal, P. et al., Management of respiratory failure in severe
neuroparalytic snake envenomation. Neurol. India, 2001, 49, 25–28.
40. Kuch, U. et al., Severe neurotoxic envenoming by Wall’s Krait
(Bungarus walli) in Bangladesh and Nepal. Inaugural Conference
on Global Issues in Clinical Toxinology, Melbourne, Australia, 2008.
41. Faiz, A. et al., The greater black krait (Bungarus niger), a newly
recognized cause of neuro-myotoxic snake bite envenoming in
Bangladesh. Brain. J. Neurol., 2010, 4, 1–13.
42. Whitaker, R. and Whitaker, S., Venom Research Project – Interim
Report to the Madras Crocodile Bank Trust, 2 February 2011.
43. Whitaker, R. and Captain, A., Snakes of India the Field Guide,
Draco Books, Chengalpattu, India, 2004, p. 481.
44. Chandnu, T., A case of snakebite possibly by the Himalayan
white-lipped pit viper, Cryptelytrops septentrionalis. Here be
Dragons, Blogspot of MCBT/CFH, July 2007, p. 1.
ACKNOWLEDGEMENTS. We are grateful to David Warrell, Ashok
Captain, David Williams and Gerry Martin for advice and for com-
menting on early drafts of the paper, and to the staff and trustees,
Madras Crocodile Bank/Centre for Herpetology, for their continued
help and support.
Received 18 June 2012; accepted 23 July 2012
... Snake antivenom is one kind of therapeutic serum that is the only effective treatment choice for snake bite envenoming [24], [25]. Antivenom may be a mono variant or poly variant but the second one is best for treatment cause biting a snake may not be familiar to the victim [26]. A recent study reveals that 48 public laboratories produce antivenom across the world. ...
... A recent study reveals that 48 public laboratories produce antivenom across the world. Among them, 04 (four) are running in India and it is the largest antivenom producer as well [3], [5], [26]- [28]. A previous study reported that some countries provide free antivenom for snake bite envenoming but most of the common practice is to buy the antivenom by victim [28]. ...
... The expenditure on antivenom treatment may be decreased by producing the antivenoms from local venomous snakes despite purchasing or manufacturing from abroad. The composition of snake venom and potency varies depending on geo-climate and environmental factors [26], [39]. The polyvalent antivenom from local snake venoms may reduce the doses as well as complexity to patients. ...
Article
Full-text available
Snakebite is a buzzing issue among neglected diseases. Bangladesh is one of the most affected zones by snake bites due to its geographical location, tropical climatic conditions, high population density, agricultural practices, human-wildlife interaction, etc. Treatment facilities are getting interrupted owing to a lack of sufficient antivenom and health care providers, the high cost of antivenom, delayed reporting, etc. Although there are several species of both poisonous and non-poisonous snakes available in Bangladesh, no regional or country epidemiological data and organized snake farming systems are available. There is an opportunity to produce antivenoms through snake farming in Bangladesh. Researchers, policymakers, and other respected authorities should look into this issue to reduce the snake bite burden as well as the opportunities of a new era. In addition, the development of the local polyvalent antivenom may decrease treatment costs by developing medical facilities in rural networks.
... Representing just 5% of India's population, Tamil Nadu has been estimated to contribute around 20% of the official national snakebite mortality cases (Samuel et al., 2020). This has been suggested to be a product of high agricultural reliance, a rural population living in poverty, and a high abundance of India's four medically significant venomous snakes (Samuel et al., 2020); the spectacled cobra (Naja naja), the Russell's viper (Daboia russelii), the saw-scaled viper (Echis carinatus), and the common krait (Bungarus caeruleus) (Whitaker & Whitaker, 2012). Bites are most likely to occur at lower altitudes, specifically less than 500 m above sea level, in correlation with rainfall and crop harvesting (April-June and September-October) (Suraweera et al., 2020;Vaiyapuri et al., 2013). ...
... Bites are most likely to occur at lower altitudes, specifically less than 500 m above sea level, in correlation with rainfall and crop harvesting (April-June and September-October) (Suraweera et al., 2020;Vaiyapuri et al., 2013). The four medically significant species are terrestrial but vary in nocturnal and diurnal activity patterns, causing a consistent risk for agricultural workers (Whitaker & Whitaker, 2012). While currently listed as "least concern" on the IUCN's Red List (IUCN, 2022) and protected under The Wildlife Protection Act (1972) of India, conflict with humans and land use change threaten these species' persistence in India (Janani et al., 2016). ...
Article
Full-text available
Negative interactions between humans and venomous snakes are increasing, with the World Health Organization committed to halving snakebite deaths and disabilities by 2030. Evidence‐based strategies are thus urgently required to reduce snakebite events in high‐risk areas, while promoting snake conservation. Understanding the factors that drive the adoption of snakebite prevention measures is critical for the effective implementation of snakebite management strategies. We conducted in‐person questionnaires ( n = 535 respondents) with rural agricultural communities within the Thiruvarur District of Tamil Nadu, India, a national snakebite hotspot. Using a health belief model framework, we explored current snakebite prevention measures and factors impacting their adoption. The majority of respondents reported using multiple snakebite prevention measures. Perceived self‐efficacy and perceived risk frequency of snakebites were important overall predictors of future adoption, whereas education, gender, relative wealth, and current adoption were important for specific measures. Achieving international commitments to support human–snake coexistence will require collective and collaborative action (e.g., governments, donor agencies, civil society organizations, researchers, and communities) underpinned by behavioural insights and context‐specific solutions.
... Certain antivenoms have only limited efficacy, and their trustworthiness remains unvalidated in comprehensive clinical trials. 18 Venom analysis revealed substantial geographical disparities in venom, influencing antivenom effectiveness and indicating the necessity for region-specific antivenoms to enhance treatment outcomes. 19 The greater black krait ( Bungarus niger ), a species found in Uttarakhand, Assam, Sikkim and Arunachal Pradesh, has been associated with multiple envenomation incidents and fatalities in these regions. ...
Article
Full-text available
India faces substantial challenges from snakebite envenoming secondary to the high morbidity, mortality and financial burden, particularly in rural communities. While concentrated on the ‘Big Four’ venomous species, recent research indicates a necessity to expand the focus to encompass additional medically relevant species. This review emphasizes the geographic heterogeneity in venom among these snakes, which impacts antivenom effectiveness and necessitating region-specific formulations. This analysis highlights the shortcomings of current antivenoms and identifies non–Big Four species involved in snakebite envenoming, advocating for an urgent shift to inclusive antivenom strategies that integrate local venom profiles to enhance treatment effectiveness and thereby reduce snakebite-related morbidity and mortality. Improved training for healthcare providers and enhancements in anti-snake venom quality are essential for meeting the World Health Organization’s 2030 Sustainable Development Goal objective of halving snakebite-related fatalities and disabilities. Incorporating snakebite management into national health programs and conducting epidemiological research systematically are crucial to mitigating this preventable health concern.
... The most affordable POC device identified in this review was the microINR system, which costs 500 USD for the device and 2 USD per test cartridge. Considering that a course of antivenom treatment typically costs over 50 USD [83,84], and that a POC device could facilitate more effective allocation of antivenom, it is possible that the cost of the device would be off-set. Formal cost-effectiveness studies would be important to understand the indirect cost savings of implementing POC tests in these settings. ...
Article
Full-text available
Venom induced consumption coagulopathy (VICC) is a common complication of snakebite that is associated with hypofibrinogenaemia, bleeding, disability, and death. In remote tropical settings, where most snakebites occur, the 20-minute whole blood clotting test is used to diagnose VICC. Point-of-care (POC) coagulation devices could provide an accessible means of detecting VICC that is better standardised, quantifiable, and more accurate. In this scoping review, the mechanistic reasons that previously studied POC devices have failed in VICC are considered, and evidence-based recommendations are made to prioritise certain devices for clinical validation studies. Four small studies have evaluated a POC international normalised ratio (INR) device in patients with Australian Elapid, Daboia russelii and Echis carinatus envenoming. All of these studies used POC INR devices that rely on a thrombin substrate endpoint, which, unlike laboratory-based INR measurement, is known to underestimate INR in patients with hypofibrinogenaemia. Seventeen commercially available POC devices for measuring INR, activated clotting time (ACT), activated partial thromboplastin time (aPTT), fibrinogen, D-dimer, and fibrin(ogen) degradation products (FDP) have been reviewed. POC INR devices that detect fibrin clot formation, as well as a novel POC device that quantifies fibrinogen were identified, that show promise for use in patients with VICC. These devices could support more accurate allocation of antivenom, reduce the time to antivenom administration, and provide improved clinical trial outcome measurement instruments. There is an urgent need for these promising POC coagulation devices to be validated in prospective clinical snakebite studies.
... This polyvalent antiserum has the potential to neutralize the venoms of the 'big four' snake species found in India. [19] While using this lyophilized antiserum, it was reconstituted into solution as per manufacturer's guidelines but in double strength by adding half the volume of water than mentioned. SVA was expressed quantitatively in terms of reconstituted volume. ...
Article
The commercial availability of the snake venom antiserum (SVA) significantly improved the chances of survival of snakebite victims and eventually, the research on phytotherapeutics for snake envenomation declined. India is the capital of snakebite deaths and needs safer molecules for treatment. Systematic investigations on phytotherapeutics are carried out on many animals, and most of them are sacrificed. The study evaluates the possibility of reducing the number of animals sacrificed in venom research by monitoring physiological parameters. Respiratory and electrocardiographic (ECG) monitoring was done in anaesthetized rats after administration of Naja naja (neurotoxic) and Daboia russelii (cytotoxic) venoms separately. Anti-venom action of Woodfordia fruticosa (Lythraceae) extract was evaluated against these venoms and SVA was used as the positive control. Physiological parameters were recorded with the LabChart® program and PowerLab® system coupled with 3 electrode ECG bioamplifier and a respiratory flow-head with a custom-designed mask. Sinus bradycardia was a major cardiac effect imparted by both venoms. The absence or inverted appearance of P-waves, PR prolongation, changes in QRS configuration and QT prolongation were induced by venoms. Significant respiratory depression was observed with N. naja venom and significant ECG changes were observed with D. russelii venom. W. fruticosa extract significantly prevented envenomed animals from developing sinus bradycardia (P < 0.001) for both venoms comparable to the action of SVA. W. fruticosa extract reversed severe respiratory depression induced by N. naja venom up to 70% and D. russelii venom up to 91%. Prolongation of PR and QT intervals induced by both the venoms was significantly reversed by W. fruticosa extract (p < 0.001). Development of RSR’ configuration in ECG and changes to cardiac axis induced by D. russelii venom were reversed by W. fruticosa. Possible mechanisms of venom toxicity and their reversal can be studied with such well-designed methods, and using sub-lethal venom doses would reduce animal sacrifices. Correlating prospective clinical case studies of snakebite victims with these controlled animal studies can generate base data for future venom research.
... Hence, the possibility of poor efficacy of ASV is highly unlikely. Polyvalent ASV in India is primarily obtained from the snakes of Tamil Nadu region, 11 where E carinatus sochureki (which is restricted to the western region of India) is not found. This raises a strong possibility that the polyvalent ASV available in India is likely to be poorly effective against bites from this snake. ...
Article
Full-text available
Available online xxx Keywords: Snake bite E. carinatus sochureki Thrombotic microangiopathy Venom-induced consumption coagulopathy a b s t r a c t Snake bite is a major cause of mortality in the Indian subcontinent. The condition is fraught with the problem of under reporting. Most bites in India are caused by the "Big 4 species," based on this, the antiesnake venom (ASV) is also sourced from these species only. It has been observed that the venom of snakes from different regions respond differently to it, as is sourced mainly from snakes of southern region of India. We present a case of a saw-scaled viper (SSV) bite, where the patient had unusual presentation of thrombotic microangiopathy (TMA) along with venom-induced consumption coagulopathy (VICC). The patient was resistant to ASV and finally succumbed. The snake was identified as Echis carinatus sochureki (a subspecies of SSV). This case highlights that VICC is the commonest presentation in a SSV bite, rather than disseminated intravascular coagulation (DIC). The organ failure in such bites is due to rare coexistence of TMA (especially in an E carinatus sochureki bite) and should not be attributed to DIC. It also identifies that the polyvalent ASV produced in India is not effective against E carinatus sochureki bite.
... As a result, patients require a large dose of antivenom administration for recovery, where a study in a North Indian hospital reported 51.2 antivenom vials for treating elapid and 31 vials for viperid envenomation (Sharma et al., 2005), whereas, another study for neuroparalytic symptoms after envenomation reported up to 90 vials of antivenom being administered (Agrawal et al., 2001). The average price of these polyvalent antivenom for a 10 mL vial in 2010 cost between INR 550-935/vial (US$ 6.5-11) (Whitaker and Whitaker, 2012). A high antivenom dosage requirement is not only associated with a significant financial burden on the patient and his family but also associated with availability issues, storage issues (requirement of low temperature), batch-to-batch variability issues, and their side-effects such as the risk of pyrogenic fever and anaphylactic reactions in patients (Bhatia et al., 2022;Stone et al., 2013;Tongpoo et al., 2018). ...
Article
Full-text available
Bungarus fasciatus also referred to as the Banded krait is a snake which possesses venom and belongs to the Elapidae family. It is widely distributed across the Indian subcontinent and South East Asian countries and is responsible for numerous snakebites in the population. B. fasciatus possesses a neurotoxic venom and envenomation by the snake results in significant morbidity and occasional morbidity in the victim if not treated appropriately. In this study, the efficacy of Indian polyvalent antivenom (Premium Serums polyvalent antivenom) was evaluated against the venom of B. fasciatus from Guwahati, Assam (India) employing the Third-generation antivenomics technique followed by identification of venom proteins from three poorly immunodepleted peaks (P5, P6 and P7) using LC-MS/MS analysis. Seven proteins were identified from the three peaks and all these venom proteins belonged to the phospholipase A2 (PLA2) superfamily. The identified PLA2 proteins were corroborated by the in vitro enzymatic activities (PLA2 and Anticoagulant activity) exhibited by the three peaks and previous reports of pathological manifestation in the envenomated victims. Neutralization of enzymatic activities by Premium Serums polyvalent antivenom was also assessed in vitro for crude venom, P5, P6 and P7 which revealed moderate to poor inhibition. Inclusion of venom proteins/peptides which are non-immunodepleted or poorly immunodepleted into the immunization mixture of venom used for antivenom production may help in enhancing the efficacy of the polyvalent antivenom.
Article
Snakebites are critical medical emergencies that significantly contribute to emergency department visits during monsoon seasons. This case report details a patient who experienced simultaneous arterial and venous thrombosis of major intracranial vessels due to venom-induced consumptive coagulopathy. Additionally, the patient developed diffuse alveolar haemorrhage (DAH), highlighting the severe impact of these uncommon complications on prognosis. Early recognition of such rare conditions depends on maintaining a high index of suspicion.
Article
Venomous snakebite is a neglected tropical disease and disease of poverty, affecting hundreds of thousands of people annually. The only effective medical intervention for snakebite is antivenom, produced primarily using captive venomous snakes as a source of venom. This paper analyzes snakes’ welfare at venom labs within this global health context. I recommend significant changes to improve the welfare of captive snakes, particularly in light of recent ethological research and attention on snakes. These recommendations are broadly consequentialist, aiming to improve the lives of the snakes and ensure that people have increased access to affordable antivenom.
Article
Full-text available
Prospective studies of snake bite patients in Chittagong, Bangladesh, included five cases of bites by greater black kraits (Bungarus niger), proven by examination of the snakes that had been responsible. This species was previously known only from India, Nepal, Bhutan and Burma. The index case presented with descending flaccid paralysis typical of neurotoxic envenoming by all Bungarus species, but later developed generalized rhabdomyolysis (peak serum creatine kinase concentration 29,960 units/l) with myoglobinuria and acute renal failure from which he succumbed. Among the other four patients, one died of respiratory paralysis in a peripheral hospital and three recovered after developing paralysis, requiring mechanical ventilation in one patient. One patient suffered severe generalized myalgia and odynophagia associated with a modest increase in serum creatine kinase concentration. These are the first cases of Bungarus niger envenoming to be reported from any country. Generalized rhabdomyolysis has not been previously recognized as a feature of envenoming by any terrestrial Asian elapid snake, but a review of the literature suggests that venoms of some populations of Bungarus candidus and Bungarus multicinctus in Thailand and Vietnam may also have this effect in human victims. To investigate this unexpected property of Bungarus niger venom, venom from the snake responsible for one of the human cases of neuro-myotoxic envenoming was injected into one hind limb of rats and saline into the other under buprenorphine analgesia. All animals developed paralysis of the venom-injected limb within two hours. Twenty-four hours later, the soleus muscles were compared histopathologically and cytochemically. Results indicated a predominantly pre-synaptic action (β-bungarotoxins) of Bungarus niger venom at neuromuscular junctions, causing loss of synaptophysin and the degeneration of the terminal components of the motor innervation of rat skeletal muscle. There was oedema and necrosis of extrafusal muscle fibres in envenomed rat soleus muscles confirming the myotoxic effect of Bungarus niger venom, attributable to phospholipases A₂. This study has demonstrated that Bungarus niger is widely distributed in Bangladesh and confirms the risk of fatal neuro-myotoxic envenoming, especially as no specific antivenom is currently manufactured. The unexpected finding of rhabdomyolysis should prompt further investigation of the venom components responsible. The practical implications of having to treat patients with rhabdomyolysis and consequent acute renal failure, in addition to the more familiar respiratory failure associated with krait bite envenoming, should not be underestimated in a country that is poorly equipped to deal with such emergencies.
Article
Full-text available
Snake bite is one of the most neglected public health issues in poor rural communities living in the tropics. Because of serious misreporting, the true worldwide burden of snake bite is not known. South Asia is the world's most heavily affected region, due to its high population density, widespread agricultural activities, numerous venomous snake species and lack of functional snake bite control programs. Despite increasing knowledge of snake venoms' composition and mode of action, good understanding of clinical features of envenoming and sufficient production of antivenom by Indian manufacturers, snake bite management remains unsatisfactory in this region. Field diagnostic tests for snake species identification do not exist and treatment mainly relies on the administration of antivenoms that do not cover all of the important venomous snakes of the region. Care-givers need better training and supervision, and national guidelines should be fed by evidence-based data generated by well-designed research studies. Poorly informed rural populations often apply inappropriate first-aid measures and vital time is lost before the victim is transported to a treatment centre, where cost of treatment can constitute an additional hurdle. The deficiency of snake bite management in South Asia is multi-causal and requires joint collaborative efforts from researchers, antivenom manufacturers, policy makers, public health authorities and international funders.
Article
Full-text available
Most epidemiological and clinical reports on snake envenoming focus on a single country and describe rural communities as being at greatest risk. Reports linking snakebite vulnerability to socioeconomic status are usually limited to anecdotal statements. The few reports with a global perspective have identified the tropical regions of Asia and Africa as suffering the highest levels of snakebite-induced mortality. Our analysis examined the association between globally available data on snakebite-induced mortality and socioeconomic indicators of poverty. We acquired data on (i) the Human Development Index, (ii) the Per Capita Government Expenditure on Health, (iii) the Percentage Labour Force in Agriculture and (iv) Gross Domestic Product Per Capita from publicly available databases on the 138 countries for which snakebite-induced mortality rates have recently been estimated. The socioeconomic datasets were then plotted against the snakebite-induced mortality estimates (where both datasets were available) and the relationship determined. Each analysis illustrated a strong association between snakebite-induced mortality and poverty. This study, the first of its kind, unequivocally demonstrates that snake envenoming is a disease of the poor. The negative association between snakebite deaths and government expenditure on health confirms that the burden of mortality is highest in those countries least able to deal with the considerable financial cost of snakebite.
Article
Full-text available
Envenoming resulting from snakebites is an important public health problem in many tropical and subtropical countries. Few attempts have been made to quantify the burden, and recent estimates all suffer from the lack of an objective and reproducible methodology. In an attempt to provide an accurate, up-to-date estimate of the scale of the global problem, we developed a new method to estimate the disease burden due to snakebites. The global estimates were based on regional estimates that were, in turn, derived from data available for countries within a defined region. Three main strategies were used to obtain primary data: electronic searching for publications on snakebite, extraction of relevant country-specific mortality data from databases maintained by United Nations organizations, and identification of grey literature by discussion with key informants. Countries were grouped into 21 distinct geographic regions that are as epidemiologically homogenous as possible, in line with the Global Burden of Disease 2005 study (Global Burden Project of the World Bank). Incidence rates for envenoming were extracted from publications and used to estimate the number of envenomings for individual countries; if no data were available for a particular country, the lowest incidence rate within a neighbouring country was used. Where death registration data were reliable, reported deaths from snakebite were used; in other countries, deaths were estimated on the basis of observed mortality rates and the at-risk population. We estimate that, globally, at least 421,000 envenomings and 20,000 deaths occur each year due to snakebite. These figures may be as high as 1,841,000 envenomings and 94,000 deaths. Based on the fact that envenoming occurs in about one in every four snakebites, between 1.2 million and 5.5 million snakebites could occur annually. Snakebites cause considerable morbidity and mortality worldwide. The highest burden exists in South Asia, Southeast Asia, and sub-Saharan Africa.
Chapter
This is the first book to present a multidisciplinary approach to venomous snake research. As well as focusing on the medical aspects of snake venoms and the effects of snakebites, the book examines the evolution and ecology of venomous snakes, which are so crucial in the search for snakebite antidotes. The book has been written to be accessible to an audience of varied scientific backgrounds. Due to the wide range of information, it will be of great interest to scientists and students involved in any aspect of venomous snake research, whilst also appealing to the growing band of amateur enthusiasts.
Book
Please note that to obtain a copy of the book Snakes of India-the Field Guide, please write to <pavithra@madrascrocodilebank.org>
Article
Vipera russelli venom induces predominantly neurotoxic, myotoxic necrotic and hemorrhagic symptoms in experimental animals and has several hydrolytic enzyme activities. In this study, V. russelli venom is characterized both as a PLA2 and as a toxin. Anti PL-V Ig (antibodies to a toxic phospholipase A2 VRV PL-V of V. russelli venom) nullifies the toxicity of whole V. russelli venom to a great extent. The neurotoxic symptoms vanish completely in the presence of anti PL-V Ig. The cross reacting components of whole V. russelli venom were removed by precipitating them from whole venom by the addition of anti PL-V Ig. The non-cross reacting components present in the supernatant were checked for toxicity. There was a significant reduction in toxicity. The LD50 value of the supernatant had increased from 4.1 mg/kg body weight to 11.7 mg/kg body weight and it showed about 34% of the total venom phospholipase A2 activity. It had edema forming, hemorrhagic and hemolytic activity but failed to induce neurotoxic, anticoagulant and myotoxic effects.