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At Nepal's northern border with Tibet is the great. Himalaya Range, capped by Mount Everest itself. (8848 m) and including Cour of the other eight highest.
VOLUME 28 1998 ISSN: 0049-4755

Doctor

This quarterly publication of the Royal Society of Medicine Press is .. .

* A journal for those who serve the medical needs of populations in tropical and developing countries, in particular those in district level hospitals and community services

* A forum for practitioners to contribute original work arising from tropical experience

* A vehicle for teaching the appropriate application of current knowledge to the special circumstances of remote communities

* A means of communication between medical staff dealing with the same disease problems in many different environments

EDITOR : Dr Michae l E Jones

Th e

CHAIRMAN: Professor E H 0 Parry

R O YAL

S OC IETY of MEDI CINE PRESS

LWilred

ASSISTANT EDITORS : Dr T E L ancaster Mr F I Tovey Dr M Corachan Professor H Folmer Mr David Goodh all

Professor G J Johnso n Dr J Town send

INTERNAT IONAL ADV ISORY BOARD: Dr JemaJ Abdulkadir (Ethiopia) Professor R G Barruzzi (Brazil) Professor Paul C Y Chen (Malaysia) Professor Nurul Islam (Banglades h) Professor Iftu khar A Malik (Pakis tan) Dr D A Meira (Brazil ) Dr Sami ran Nundy (India)

Dr J C Pinto Dias (Brazil )

Professor Ro nald E Pust (US A) Professor Zohair A Sebai (S audi Arabia) Professor V Seminario de Rivera (Penl)

TROPICAL DOCTOR

VOLUME 28

NCMBER 4 OCTOBER 1998

EDITORIAL

Snakes and snake bite

lD

Nepal

At Nepal's northern border with Tibet is the great Himalaya Range, capped by Mount Everes t itself (8848 m) and in cluding Cour of the other eight highest mountains in the world South of the Kathmandu Valley at the centre of the country are the lesser mountains of the Mahabh at'at Range and Churia Ghati Hill s, below 3000m , and in th e far so uth . stretching to Indi a, are the fertile alluvial Terai Plains with scattered swamps a nd hard wood dnd ba mboo forests. The distributi on of the 14 species of venomo us snakes known to inhab it Nepa l is determined by geography and climatel.2. The range of only one species. the Him a la ya n pit viper (Agkislrodon liimala.\'ww.l) , ex tends into the higher elevation s. Th ere is a record in the Indi an Museum at Calcutta of a specimen collected at the foot of the Dh ,umsala Glacier (Himacha[ Pradesh, India) at [6000 feet (48 7 m)l Thi s may be a world altitude record for snakes". The four other species of pit viper (Tril11e1'esurus olbolabris, loca l name 'hareu' or green snakes). T. jerdonii, T. .\' Iejnegl'ri and Ol'opliis 1110171icolo inhabit wooded montane slopes below :l000 rn. Russell's viper (Dohaill russC'lii, local name 'baghe' or 'leopard-spotted') (figure [). an impo rtant ca use of snake bite mortality a nd mor bidity in many pa rts of Asia . occ urs in western Nepa l. Three species of kraits [BlIl7garus clII:'I'/deus (Figure 2). B. li/sciolu.1 and B. sindwws) occur below 2000 m, so me­ tim es in farming areas. while the two species of lypica l cobra, both of great medical importance (monoce llate Naja k{{oulhia, loca l name 'paniadaraj' and spectacled Naja l1aja - figure 3) and the world's largest ve nomous snake , the king cobra (Ophiophl1gus hannah) are confined to the Teral. MacCle[land 's coral snake (Hemibungllrus macclellili/di univirgaills) is a lowland species.

Figurr I. Russe/l's riper I Daboia russe lii russelii ). RO_I'al

Bardill NUliol/a/ Park, Nepal (cop)Tighl Mark 0 'Sheo)

Figure 2. CommOI/ Inclilll7 krail (Bungarus caerlilells) Roml B{j/'diu Nalional Parle Nepal (cop.lTigll/ Mark O'Shea )

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Figurl' 3. Common Indian cobm (Naja naja). Royal Burilia Na/iollal Park, Nl'pal (copl'righ/ iv/ark 0 'S/zl'u)

Little has been published on the problem of snake bite in Nepal' S Most is known about the clinical pattern in envenomed patients presenting to the former British Military Hospital in Oharan (altitude about 400 m abo\" sea level). The Director of the National Zoonosis and food Hygiene Research Centre in Kathmandu, Dr DO Joshi, estimates that there are between 150 and 200 deaths in Nepalese hospitals each year. Oharan in the eastern foothills, Heteaunda, Butwal, Chitwan, Nepal­ ganj in the west and Ohangadi in the far west, are thought to have a particularly high incidence of snake bites. According to a World Health Organization (WHO) report, more than 20 000 cases of snake bite with 1000 deaths . occur every year in Nepal". Dr Y Sawai. a WHO consultant set up an epidemiological study in 15 district hospitals. From 1980 to 1985,3189 cases were treated with 144 deaths (case fatality, 4.5%). The highest seasonal incidence or bites is during the

TJ'Opical DoC/o/', OC/ohcr 1998 monsoon from June to October, with a peak in August. Much remains to be learnt about the medicallv­ important species In the different regions of Nepal. It is clear from the small literature, including the paper by Hansdak 1'/ al. published III this edition or Tropica/ Doc/or (p. 223), that bites are being inAicted by species with neurotoxic venoms (notably cobras and kraits) and by vipers producing severe local bleeding, swelling, bruising, blistering and necrosis together with systemic bleeding and clotting disorders. An unusual case of fatal snake bite was rerorted by I.ugen Kramer of the Musee de I'Histoire Naturelle, (jeneve 2 While collecting reptiles and amphibians ned[ Pokhara in 1964, his friend, Hans Schnurrenberger was bitten by a Juvenile srecimen of the elarid species, H mace/ellandi 1II1i­ virga/liS. approximately 30 cm long, and no thicker than a pencil. There were no symptoms for 2 h and so he ignored the bite, but 6 h later he develored pain on movement and died of resriratory paralysis 8 h after the bite. This fatal accident illustrates the risk of handling potentially dangerous species and, in small specimens, of underestimating the lethal capacity of their venom. There is a strongly held local belief tha t the bite of the chequered kneelback (Xenochrophi.I-Na/rix-p!.ICC/{or) is lethal to cattle but harmless to humans. Members 01' the superficially similar genus of keel backs (RhaiJdophis) are venomous, back-fanged colubrid snakes, two species or which (R. subminia/lis and R. /igrinus) have caUSed life-threatening envenoming in human victims 9 There are no records of bites by R. himllllll'anlis which occur 1I1 Nepal. About 3000 vials of polyspecific anti venom (iVa/a naja. Bungurl/,\ Clll!rlllnls. Daboia rllsselii, Echis carinu­ {liS) manufactured by the Serum Institute of India are imrorted from India each year but this is insufficient. Because of chronic shortage of anti venom in govern­ ment hospitals and belief in traditional remedies, most victims 0[' snake bite in Nepal do not Seek heir in wes tern style hospi ta Is and d ispensa ries. Popu lar traditional methods of treatment involve chanting, incantations. attempts to suck the venom from the site or the bile (e.g. using the anal sphincter 0[' a chicken) and the arplication of mithridates, lexins, tiriyaq and latex from a climbing plant known as the snake gourd. Pastes of herbal medicines, snake stones and special kinds or earth are applied to the wounds and multiple tourniquets and local incisions are popular firsl aid methods. Only when the symptoms deteriorate are the patients brought to hospital but many are thought to die on tl1e way. As In so many tropical countries, snake bite in Neral is an occupational hazarcl fc)I' poor rural people and is not reg~lrded as an important medical problem by most senior health officials in the capital city. To discover how to reduce the morbidity and mortality it will be necessary first to carry out prospective studies in different regions of the country in which the srecies of snake responsible for bites can be determined by

Tr op ical DoC/ or , O c/o/)cr 1998

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immunod iag nosis. Approp ri ate a nti venoms can th en be identified a nd their efficacy and sa fet y investi gated. Results of this resea rch will be relevan t to bordering areas of Indi a. Sikkim , Bhuta n a nd Tibet. BJ SHNli BA Hr\DAR BHETW A L

V DC-Bljalpllm-2, PO Baradhill(fs,

/v/ol1ol/([ri Dis/ ritl,

(l.iP{J(//

M ARK O ' SHE A

Buckingham Road, Penll, WolI'('rlwn1p/on WV4 5 TJ . UK 46

E-l1I a il: osl1('O ((I sna/(emos.dellloll .co.uk D AV I D

A W A RRELL D I'v1 FRCP

Centre lor Tropical /v/edicine (Ullil'er si/y 0/ Ox/ord) , John Rw lcli/(e Hospiwl, H eadillg/on, Ox/cJr(/ OX3 9 DU. UK E -II/ail. davie!.II 'arr!! I/(!'. ndm.()x .ac.uk R EI ER E"\. CS

Swan LW, LC\' ito n, AE. Th e he rpeto logy o f Nep a l: a his to ry, c hecklisl and zoogeog ra phi ca l a na lys is o r the

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h.:rpclOiauna. fm c Calililr/lia Ac",1 S ci 1962;32 : I 03 4­ Kramer F. luI' Schl;in ~\!nra lln:1 Nc' IXds . Rer Sui."\(' Z oolog l' 1977:84: 121 - 6 1

_, ScJat r vVL . Lis/ \' .:I ·SlIakes ill Ihe illdilll/ .\1l1setlll1 . Cdkutta : Tr usk es o r the In dian Museum, I Xl) I 4 G loy u H K, Conant R. SI10" ,'\ or /111': A gk i., rot!ol7 COll1ple .r­ A /vionogrophic Rcrir'l\' Socie ty fo r the Stud y o f Amphi­ bIans J nd Repli les. O hio: Oxford. Jl)90:26 1 5 For'y the-J,.tUch WF . 1\ , ,,ric, of snak e bites . .1 R /11'1"-1' !l4ec/ Co rl''' IlJ - ' :12l: D X 6 World l-J"" ltl l Org3nizJtion. Zoonotic di'~ J se control. R lsei ine cridel11 iologic;lI , (tidy on sn J ke-bitc treatment and ma n:l ge­ menl. Wl'ck lI' i:i'idell1iolog ReI' 1987 :42 :3 19- 20 7 Hear BJ , Co wan GO. T h" ep idemiology o f sna ke bite pre,e nting to Brilish Mil ila ry Hosp it aL Dhara n during 1989 . J R Arm\' .I1ed Corp" 1991 : J37 : 123 5 R Joshi DD, Tor iba M, Kawalllura y , Hayash i Y. Snak e bileS In Ter'li regio n of Ne pal. In : i l/ le rnol ilJl7al Cuu ference (J11 El1rir(Jl/ n /('11I o! O cnlrrel1 n' or Snoke 8 i/('s ol/(llhe i( ,'Vl i'd iml Trealil1et1l 011(1 Prophrlaxi l·. lt40ebw hi City. JUpUII 3U ;/lIglis/- 1 Seplel1/ncr 199 7 [Abstra ctsJ: r 7

9 Warrell DA . C lini ca l tox icology of sna ke bite in Asia. In Meier J , White J, eds . H Olldboo/{ Clinical Toxic()/J)~l' (lr Animal V e l/UIIIS olld Poisol1S . Boca Ra ton : CRC Press . 1995:493 594

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