International Journal of Livestock Research ISSN 2277 ... - eJManager

International Journal of Livestock Research ISSN 2277-1964 ONLINE www.ijlr.org

Vol 3(1) Jan’13

Gnathostomiasis - An Emerging Nematodal Zoonotic Disease Mahendra Pal*, Hayat Seid, Bulto Giro, Berhane Wakjira and Jewaro Abdo

Addis Ababa University, College of Veterinary Medicine and Agriculture, P.O. Box No.34, Debre Zeit, Ethiopia *Coressponding author: [email protected]

Abstract Gnathostomiasis, an emerging food-borne helminthic zoonosis, is reported in tropical and subtropical regions of the world. The disease is caused by the third stage larvae of several species of the genus Gnathostoma. The life cycle of the helminth Gnathostoma is complex as it needs two intermediate hosts. Man acts as an accidental host, and acquires infection by ingesting raw or undercooked or unprocessed meat of the freshwater fish, chicken, duck, frog, pig, and snake. Cutaneous and visceral form of disease is reported in human beings. The involvement of central nervous system carries high morbidity and mortality. Laboratory help is required to diagnose Gnathostomiasis. Disease should be differentiated from angiostrongyliasis, cutaneous larva migrans and trichinosis. Chemotherapy is done with albendazole and ivermectin. However, surgical excision of parasite becomes imperative when vital organs are affected. Thorough cooking of meat in endemic areas and health education of people about the importance of safe cooking are considered the best strategy to control this emerging food-borne nematodal zoonosis. Further studies on the diagnostic techniques and epidemiology of gnathostomiasis seem imperative. Key words: Emerging zoonosis, Fish, Gnathostomiasis, Humans, Meat, Nematode Introduction Gnathostomiasis, sometimes referred to as cosular disease, larval migrans profundus, nodular migratory eosinophilc panniculitis, panniculitis nodular migratoria eosinofilica,Shanghai’s rheumatism ,tuao chid and Yangtze river’s oedema,

is an emerging helminthic zoonosis ( Samantaray and Topno,2006;

Pal,2007 and Herman and Chiodini,2009).The disease usually occur in sporadic form and involving many persons in the form of outbreak and may carry high morbidity and mortality if left untreated ( Nagler et al.,1983; Chai et al.,2003 and Herman and Chiodini,2009 ).Gnathostomiasis has been reported from several counties of the world but foci of endemicity have been predominately in Japan and Thailand ( Herman and Chiodini,2009).Migration of people from the tropical and subtropical countries to settle in the West has been recognized as one of the important factors to spread the infection to the non endemic regions ( Herman and Chiodini,2009).The source of infection is exogenous and transmission occurs following the consumption of raw or undercooked freshwater fish or other meats( Pal,2007 and Herman

Host

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emerging foodborne nematodal zoonosis.

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and Chiodini,2009).The present communication focuses on the importance of gnathostomiasis as an


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Natural infection due to Gnathostoma has been reported in humans by several investigators from many parts of the world (Pal,2007 and Herman and Chiodini,2009).The parasite is also encountered in cat, dog, duck, eel, fish, frog, leopard, lion, mink, opossum, pig, poultry, raccoon, snake, and tiger ( Samantaray and Topno,2006;Pal,2007;Herman and Chiodini,2009;Woo et al,2011). Etiology The disease is caused by the nematode Gnathostoma which was first discovered in the stomach wall of a tiger that died due at London zoo (Owen,1836).The genus Gnathostoma which belongs to the order Spirurida that contains 12 species ( Nawa ,1991).Hitherto,only four species of Gnathostoma such as G.spinigerum,G.nipponicum,G.hispidum and G.doloresi are recorded in human beings ( Herman and Chiodini,2009). Life cycle The life cycle of Gnathostoma is complex as it is completed in definitive host and two intermediate hosts. The definitive host include the cat, dog, leopard, tiger and probably other fish eating mammals, where the adult worm lives in the stomach, producing a tumor- like mass; and adult worm releases eggs into the stomach which are excreted through the faeces. Later, the eggs embryonate in the freshwater and release the first stage larvae which are ingested by the first intermediate host, a copepod of the genus, Cyclops where they develop into the second stage larvae .When infested Cyclops are eaten by the second intermediate hosts such as the bird, eel, fish, frog and reptile, the second stage larvae are freed in the intestine and develop into third stage larvae (Herman and Chiodini, 2009). These migrate into the tissues and become encysted. When encysted forms are eaten by the definitive hosts such as cat, dog, leopard, lion, monk, opossum, raccoon and others, the larvae are freed once in the gastrointestinal tract and become matured in the stomach wall of the definitive host in about 6 months (Samantaray and Topno,2006 and Herman and Chiodioni,2009).The eggs are passed into the environment in the stool of the host about 8 to 12 months after initial ingestion of the infective third stage larvae by the definitive host (Rusnak and Lucey,1993).Humans usually get infection by eating raw or undercooked freshwater fish or other intermediate hosts like chicken, frog ,snake containing third stage larvae. Clinical manifestations in man occur as the third stage larvae migrate through the tissues, causing intermittent symptoms of cutaneous or visceral migrans (Herman and Chiodini, 2009). Transmission Humans are infected by consuming raw, undercooked or unproceeesd meat of fish, pig, chicken, duck,

of contaminated water containing copepods can also result infection to humans. Food handlers may

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bathing in water contaminated with larvae or infested copepods (Samantaray and Topno,2006).Drinking

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frog and water snake containing infective larvae (Pal,2007).Infection can also occur while working or


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contract infection through penetration of the skin by third stage larvae from the infected meat (Daengsvang, 1949). Clinical Spectrum in Man Two clinical forms namely cutaneous and visceral form are observed depending on the site of migration of larvae. Migration can take place in any part of body such as the mouth, pharynx, liver, intestine, anus, spinal cord and brain. Rarely, immature worms have been recovered from the respiratory tract, ear, eye and urinary bladder (Nagler et al.,1983 and Samantaray and Topno,2006 and

Herman and

Chiodini,2009).Most common manifestation of gnathostomiasis is localized migratory swelling in the skin and subcutaneous tissues. The swellings occur commonly in the upper extremities, trunk, neck, shoulder and other parts of body, and may last for 1 to 4 weeks. Disease may persist for 10 to 12 years. Other clinical signs include abdominal pain, nausea, cough, chest pain, haemoptysis, pleural effusion, pneumothorax, haematuria, haemtospermia, balanitis, cervicitis, profuse vaginal bleeding, ocular pain, irtits, glaucoma, uveitis, retinal scaring,eosinophilic meningitis, subarachnoid haemorrage, lachrymation, phtophobia, pruritis, urticaria, paralysis and death (Chitanondh and Rosen,1967; Nagler et al,1983; Rusnak and Lucey,1993;Pal,2007and Herman and Chiodini,2009). Epidemiology Gnathostomiasis is recognized as an emerging foodborne helminthic disease of public health significance (Mac Carthy et al., 2000; Morre et al., 2003 and Dorny et al., 2009). It is endemic in areas where people have the habit of eating raw freshwater fish or shell-fish. The disease in man has been reported from many regions of the world such as Botswana, Cambodia, China, India, Indonesia, Japan, Laos, Korea ,Malaysia, Mexico, Myanmar, Philippines, Sri Lanka, Taiwan,Thailand ,and Zambia(

Rusnak and

Lucey,1993; Rao et al.,1999;Chai,et al.,2003;Hale et al.,2003 and Herman et al.,2009).It is the most frequently diagnosed parasitic disease of the brain in Thailand and is responsible for 6% and 18 % subarachnoid haemorrages in adults and children, respectively ( Visudhiphan et al.1980). Few cases have been described from Isreal (Nagler et al.,1983) and USA (Kagen et al.,1984).Such cases were observed either in immigrants or in those persons who travelled to other countries where Gnathostomiasis is endemic.It is estimated that about 50 million residents of industrialized countries travel annually to such endemic areas which can expose them to many zoonotic pathogens (Steffen et al.,2003).In recent years , gnathostomiasis has become an increasing public health problem in Central and South America due to the consumption of ceviche which is a raw fish marinated in lime (Rojas-Molina et al.,1999) and also in

clinical manifestation recorded in these patients. Based on the epidemiological evidences, changes in dietary habits are considered the chief reasons of expansion of the geographic range of gnathostomiasis

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98 cases of gnathostomiasis in Acpulco,Mexico. Intermittent cutaneous swellings were the commonest

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Ecuador,Guatemala ,and Peru ( Herman and Chiodini,2009).Rojas and co-investigators (1999) identified


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(Herman and Chiodini, 2009).Disease can occur in sporadic as well in outbreak form.The global incidence of gnathostomiasis is not estimated as majority of cases are misdiagnosed due to similarities of symptoms of with other diseases (Samantaray and Topno, 2006). Diagnosis The tentative diagnosis of gnathostomiasis can be made by the presence of migratory skin lesions , eosionophilia and history of travel to an endemic area and consumption of raw or undercooked fish or other meat. Magnetic resonance imaging (MRI) has been used to demonstrate the migratory lesions within the spinal cord (Sawanyawisuth et al.,2004).ELISA helps to detect L3 immunoglbin G (IgG) antibody but it has sensitivity of 59 to87 % and specificity ranges from 79 to 96 % (Suntharasamai et al.,1985 and Herman and Chiodini,2009).Currently, immunoblot assay

is most widely used to

demonstrate specific 2K-kDa band to confirm the diagnosis of disease ( Herman and Chiodini,2009).The nematode can also be demonstrated in the

subcutaneous nodule by staining the tissue section by

haematoxylin and eosin technique. Skin test using intradermal injection of G. spinigerum antigen was developed in Japan but the later findings revealed lack of sensitivity and specificity (Tada et al.,1966 and Herman and Chiodini,2009). Treatment Numerous

chemotherapeutic

agents

such

as

dietylcarbamazine,

metronidazole,

praziquantel,

thiabendazole were tried both in humans and in animal models without any encouraging results (Kravichian et al., 1992. However, albendazole (400 mg b.i.d.for three weeks) has shown good response to treat cases of gnathostomiasis in humans ( Samantaray and Topno,2006). In addition, this drug can stimulate the outward migration of the larva and possibly amenable to excision (Suntharasamai et al., 1992). Ivermectin at the dosage rate of 200 mg per kg body weight per day for two days is also used in the treatment of disease (Samantarary and Topno, 2006). It is emphasized to undertake further detailed clinical trials to investigate the efficacy on the use of combined treatment with both albendazloe and ivermectin for the better management of gnathostomiasis in human patients. Control Since a wide variety of animals act as intermediate host, the eradication of the parasite from the globe may not be feasible. However, certain measures such as avoiding ingestion of freshwater fish, poultry,

the consequences of eating local delicacies will certainly minimize the prevalence of gnathostomiasis

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public to change the eating habits in areas with high levels of endemicity and tourists and migrants about

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duck, pig, frog, snake etc., proper cooking of all meats before consumption ,and health education of the


which has emerged as an important foodborne helmithic zoonosis

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in some areas of the world(

Pal,2007and Herman and Chiodini,2009). Conclusions In recent years, gnathostomiasis has been recognized as a food borne emerging helminthic zoonosis. The disease is caused by several species of Gnathostoma, the life cycle of the parasite is complex as it has two intermediate hosts. Gnathostomiasis is reported from several country of the world including India. Hitherto, there is no record of gnathostomiasis from Ethiopia. The source of infection is exogenous. The ingestion of raw or undercooked freshwater fish is the main risk s for acquisition of infection. The disease occurs in sporadic form as well as affecting many persons in the form of outbreak. Cutaneous gnathostomiasis is the most common manifestation of infection. The involvement of central nervous system carries highly morbidity and mortality rate. As the disease is under diagnosed, the exact incidence of gnathostomiasis is not estimated. Laboratory investigation is necessary to confirm the diagnosis of gnathostomiasis. Albendazole and ivermectin have been used to treat the cases of gnathostomiasis in humans. The disease can be control by consumption of cooked meat of various animals and health education to the public about the risk of eating raw meat. Acknowledgement Authors wish to express their sincere thanks to Professor Dr. Ram Krishan Narayan for reviewing our manuscript.

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Chai,J.Y.,Han,E.T.,Shin,E.H.,Park,J.H.,Chu,J.P.,Hirota,M.,Nakamura-Uchiyama,F.and Nawa,Y.2003.An outbreak of gnathostomiasis among Korean emigrants in Myanmar. American Journal of Tropical Medicine and Hygiene 69:67-73. Chitanonadh,H.and Rosen,L.1967.Fatal eosinophilic encephalomyelitis caused by the nematode Gnathostoma spinagerum .American Journal of Tropical Medicine and Hygiene 16:638-645. Daevngsvang,S.1947.Human gnathostomiasis in Siam with reference to the method of prevention. Journal of Parasitology12:319-332. Dorny,P., Praet,N., Deckers,N.and Gabriel,S.2009.Emerging foodborne parasites. Veterinary Parasitology 163:196-206. Hale,D.C., Blumberg,L. and Frean,J.2003.Case report:gnathostomisasisin two travelers to Zambia.Amercan Journal of Tropical Medicine and Hygiene68:707-709. Herman,J.S.and Chiodini,P.L.2002.Gnthostomiasis,another emerging imported disease. Clinical Microbiology Reviews 22:484-492. Herman,J.S.,Wall,E.,Van Tullekan,C.,Godfrey-Faussett,P.,Bailey,R.L.and Chiodini,P.l.2009.Emergence of gnathostomiasis in Botswana in Brtitish tourists. Emerging Infectious Diseases 15:594-597. Kagen,C.N.Vance,J.C.and simpson,M.1984.Gnathostomiasis: infestation in an Asian Migrant. Archives of Dermatology 120:508-510. Kraivichian, K.,Kulkumthorn,M.,Yingyourd,P.,Akarabovorn,P.and Paireepai,C.C.1992.Albendazole for the treatment of humn gnthostomiasis.Transections of Royal society of Tropical Medicine and Hygiene 86:418-421. Mac Carthy,J.and Moore,T.A.2000.Emerging helminth zoonoses. International journal of Parasitology30:1351-1360.

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References


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Page

17

Moore,D.A.,McCroddan,J.,Dekumyoy,P and Chiodini,P.L.2003:Gnathostomiasis: An emerging imported disease.Emerging Infectious Diseases 9:647-650. Negler, A.,Pollack,,hassoun,G.,Kerner,H.,Brazilai,D.and Lengy,J.1983.Human pleuropulmonary gnathostomiasis: a case report from Isreal.Isreal Journal of Medical Sciences 19:834-837. Nawa, Y.1991. Historical reviews and current status of gnathostomiasis in Asia.Sotheast Asian Journal of Tropical Medicine and Public Health 22( Suppl.):217-219. Owen, R.1836. Gnatostoma spinigerum n.sp.Proceedings of Zoological Society (London) 4:123-126. Pal, M.2007.Zoonoses.2nd Edition.Satyam Publishers,Jaipur,India. Rao,V.A.,Pravin,T.and Parija,S.C.1999.Intracorneal gnthostomiasis: a first case report from Pondicherry.Journal of Communicable Diseases 31:197-198. Rojas-Molina,N.Pedraza-Sanchez,S,Torres Bibiano,B.,Meza-Martinez,H.and EscobarGuiterrez,A.1999.Gnathostomiasis,an emerging foodborne zoonotic disease in Acapuco,Mexico. Emerging Infectious Diseases 5:264-266. Rusnak,J.M.and Lucey,1993.Clinical gnthostomiasis:case report and review of the English literature.Clinical Infectious Diseases16:33-50. Samantaray,S.and Topno,R.K.2006.Gnathostomiasis:An emerging parasitic zoonosis. Intas Polivet 7:473478. Sawanyawisuth,K.,Tiamkao,S.,Kanpittaya,J.,Dekumyoy,P.and Gitpimolmarg,S.2004.MRimaging findingsin cerebrospinal gnathostomiasis.American Journal of Reuroradiology 25:446-449. Steffen R.C.,deBarnardis,C.and Baos,A.2003.Travel epidemiology-global perspective. International Journal of Antimicrobial Agents 21:89-95. Suntharasamai,P.,Desakorn,V.,Migasena,S.,Bunnag,D.and Harinasuta,T.1985.ELISA for immunodiagnosis of human gnathostomiasis .Southeast Asian Journal of Medicine and Public Health 16:274-279. Suntharasamai,P.,Riganti,M.,Chittamas,S.and Desakorn,V.1992.Albendazole stimulates outward migration of Gnathostoma spinogerum to the dermis in man. Southeast Asian Journal of Tropical Medicine and Public Health 23:716-722. Tada,I.,Kasashima,K.,Nishimuta,K.and Miyahara,M.1966.Intradermal reaction with Gnathostma spinigerum antigen.Japanese Journal of Parasitology 15:256. Visudhiphan,P.S.,Chiemchanya,S.and Somnuranasim,R.1980.Causes of spontaneous sub-arachnoid haemorrhage in Thai infants and children. Journal of Neurosurgery 53:185-187. Woo,H.C.,Oh,H.S.Cho,S.H.Na,B.K.and Sohan,W.M.2011.Discovery of larval Gnthostoma nippicum in frogs and snakes from Jeju-do (Province),Republic of Korea.Korean Journal of Parasitology 49:445-448.