sign in sign up
<<
Home , Clonorchiasis, Dirofilariasis, Fasciolopsiasis, Fasciolopsis, Opisthorchis felineus

Parasitc zoonoses: Different modes of are: Foodborne Vectorborne Inanimate objects born viz. soil, (Saprozoonoses)

Based on etiology: • Helminthic i. Trematodal • Protozoal ii. Cestodal • Arthropodal iii. Nematodal

Contd.. borne diseases

Contd.. Trematode Final Intermediate host Transmission to : Man, dog and buffalo; Snail Ingestion of buski (reservoir) metacercaria on water chestnut : Man and other Snail Skin penetration S. hematobium, by cercaria S. mansoni, S. Japonicum : Man, dog, cat, pig, rat 1st snail Ingestion of cyst 2nd freshwater in fish (Chinese fluke) fishes esp. cyprinid : Man and fish eating 1st snail Ingestion of cyst felineus mammals; Dog and 2nd cyprinid fish in fish O. viverrini cat-(reservoir) : Man, dog, cat and 1st snail Ingestion of cyst Paragonimus other mammals 2nd fresh water in crab meat westermanni crabs and fishes

Fasciolopsiasis: •Fasciolopsis buski •Intestinal-ulcerous disease in humans •Humans and are final hosts; pigs are reservoirs.

Infective stage (metcercaria) via ingestion of contaminated water chest nuts and walnuts which are eaten raw.

Contd.. Occurrence:

 Areas of endemicity are large parts of the People’s Republic of and , , Bangladesh, , Thailand, and Vietnam.  Disease occurs focally and is most prevalent in school-age children.  The prevalence of infection in children ranges: 60% in India 57% in China 50% in Bangladesh 25% in Taiwan, and 10% in Thailand [Nithiuthai et al. 2004] Schistosomiasis (Bilharziosis) Common in tropical and subtropical areas

Schistosome Type of infection Occurrence Reservoir Hosts caused (highly (zoonotic) prevalent)

S. hematobium Schistosomiasis of North America, Not important, but urinary tract Africa monkey, pig and rodents may play role

S. mansoni Intestinal East, Central Monkeys and rodents Schistosomiasis and West Africa, and Egypt S. japonicum Asian intestinal Southeast and Domestic ruminants, schistosomiasis East dogs, and rodents

Contd.. In India, hematobium is endemic in village Gimvi, Ratnagiri district of Maharashtara Percutaneous penetration of infective stage (cercaria)

Skin lesions Hepatomegaly Lymphadenopathy Encephalopathy

Many species are known to causing “Swimmer’s itch”, but no authentic information on prevalence in humans. Schistosome cercaria

Swimmer.’s Itch /Cercarial dermatitis Chlonorchiasis and Opisthorchiasis •Both parasitize in bile duct system Chlonorchis sinensis •Occurs in all Asian countries. •In Korea, Vietnam, Taiwan, and the People’s Republic of China, prevalence rates in humans are up to 50%. •Besides humans, cats, dogs, pigs and various carnivores are serving as final host. (Krauss et al. 2003)

Opisthorchis species Endemic areas

O. felineus Eastern and Southern Europe O. viverrini South East Asia and East Asia

Contd.. Human infection occur by ingestion of uncooked or undercooked freshwater fish, esp. cyprinid fishes e.g. carp. Paragonimiasis (Pulmonary distomiasis) • Lung flukes of the Paragonimus • is prevalent predominantly in Central, Southeast and East Asia.

High prevalence in humans is expected in north-eastern states in India as crab and dog meat are delicacies there [Borthakur et al. 2007].

Zoonotic ()

Ancylostoma Disease in humans Final host species Ancylostoma Eosinophilic enteritis Dogs caninum (occasionally) A. braziliense Cutaneous Larva Dogs Migrans(CLM) A. ceylanicum Anaemia and intestinal Dogs, jangle cats, infection civet

is the most common and is worldwide. • In Madhya Pradesh, prevalence among stray dogs reported is 89%. [Sahasrabudhe et al. 1969] and in tea growing communities in Assam , it is 72%. [Traub et al. 2004] Contd.. •Up to 60% of dogs in tea growing communities of Assam harboured A. braziliense, with 37% of dogs having mixed infections with A. braziliense and A.caninum. [Traub et al. 2004] Humans are accidental hosts and High incidence of get infection by percutaneous CLM in the area penetration of larva. and majority of individuals (67%) admitted to walking barefoot while outdoors [Traub et al. 2004].

Contd.. •There are no reports of A. ceylanicum infections in dogs despite the isolation of the hookworm in 16 out of 173 humans from the Hoogly region. [Chowdhury et al. 1972]

CLM (Creeping Eruption) Disease is acute and self-limiting. Etiological agent Favourable climate Tropical and subtropical areas Uncinaria stenocephala Cold and moderate climate

Contd.. (CLM) A syndrome caused by the invasion of inner organs (liver, lungs, brain) or the eye by larvae of the genus , and to a lesser extent, T.cati (T. mystax).

Parasite Definitive host Paratenic host Toxocara canis Dog, fox; less Essentially every prevalent in other species of mammals, canids, e.g. coyote, and birds wolf, jackal Toxocara cati Cats and other Rodents and birds felidae Racoons Rodents and birds procyonis

Contd.. •Human infections occur worldwide.

•Antibodies to T. canis are found worldwide in 2 to 14% of the human population, with higher prevalence in children than in adults (Krauss et al, 2003). •Humans are accidental hosts and get infection by accidental ingestion of embryonated eggs.

Contd.. In Dogs

 Parasitic surveys found T. canis to be most common parasite of stray dogs in Miraj (prevalence 55.8%) and Calcutta (prevalence 82%). [Joshi et al. 1977, Mapplestone.1940]

 By contrast, the prevalence of T.canis in adult stray dogs in Madhya Pradesh was found to be 2.7% and in tea growing communities in Assam , it was 11%. [Malla et al. (2002); Traub et al. 2002]

 In another study, 46% of public parks and 32% of school grounds in Andhra Pradesh were contaminated with Toxocara ova. [Kumar and Hafeez. 1998]

Contd.. In humans In a random rural survey in Haryana, 6.4% prevalence rate was found. [Malla et al. (2002)] Stunning, 23.3% prevalence has been found in Chandigarh in ocular cases and rate was 20.5% in New Delhi. [Mirdha and Khokar 2002]

4 types of clinical syndromes associated with T. canis are: 1. VLM 2. OLM 3. NEUROLOGICAL 4. COVERT

Contd.. Ocular Larva Migrans (OLM) Trichinellosis ()  of the genus Trichinella. Caused by consumption of poorly cooked meat of a number of species, especially of pig. Autopsy surveys indicate that about 2% of the population is infected globally (Uni. Of South Carolina online). More frequent in temperate than tropical areas. Incidence higher in winter season. Contd.. In India, most of human cases go undetected. [Dupouy-Camet, 2000]

In past, many human cases had been reported by different workers. [Alipuria et al. 1996; Mohan et al. 2002]

15.79% prevalence rate in panthers and tigers of the Ranthambore National Park had been reported. [Singh. 2000] In number of species like cats, bandicoots and country pigs, Trichinella infection had been described. [Uppal. 2000] Zoonotic Wuchereria bencrofti Filariasis (non-zoonotic)

Dirofilariasis (both zoonotic and non-zoonotic) Zoonotic in country In India Non-zoonotic repens (Natural host is dog)

Subcutaneous lesions only

Transmission is by bite of various mosquitoes.

Contd.. In Kerala, a high prevalence of filarial worms in the subcutaneous tissues and subconjunctival space of human beings has been found. From Kerala, 12 worm specimens of (2002 to 2004) have been identified from human cases. During the same period, in 7% dogs’ blood smears microfilariae have been detected. [Sabu et al. 2005]

Taeniasis and

Taenia species Adult tapeworm Metacestode (final host) (intermediate host) Humans Cattle, reindeer; wild saginata ruminants T. solium Humans Domestic and wild pigs; humans; also, dogs T. saginata asiatica Humans Domestic and wild pigs; also, cattle, goats, monkeys

Taeniasis (non-fatal) Cysticercosis (often neurocysticecosis and is lethal) Contd.. Cysticercosis: Neuro-cysticercosis (most common) Ocular cysticercosis Muscular and S/C connective tissue (10% in India) (Uni. of South Carolina online)

Neuro-cysticercosis is responsible for most of the morbidity/mortality observed in cases of human cysticercosis. [Pedro N. Acha and Boris Szyfres. 2003]

Contd..  At HIMS hospital, Dehradun, 32.0% patients clinically manifesting neurological signs (33/103) were positive for T. solium IgG antibodies in their sera. Among these patients children (11-20 years age group) were most affected (39.4%). [Kumar et al. 2006] In Pondichery, 14/216 (6.48 %) male blood donors are found to be positive for either anti-Cysticercus antibodies or antigens by ELISA. [Kaliaperumal et al. 2005] A number of ocular cysticercosis cases have been reported in the South India. [Kaliaperumal et al. (2005)]

In a study at IVRI, 3% prevalence of neurocysticercosis has been in the 200 slaughtered pigs’ brain samples in the Bareilly region. [Prakash et al. 2007] Contd.. Diphylobothrium latum, the largest cestode of humans. Predominantly in temperate and sub arctic areas of Northern hemisphere.

Infection by ingestion of uncooked or partially cooked contaminated fish

Contd..  Besides humans, major hosts are cats, dogs and pigs but all other fish eating mammals may become infected.

Megaloblastic and neurological signs are the manifestations of disease.

In India, the disease is uncommon. Recently, A rare case has been reported from Pondicherry, in a 5-year-old boy hailing from a fishing community. [Devi et al. 2007] one of the most important and globally widespread helminthic zoonoses.

Echinococcus Disease in humans Occurence spp. called Echinicoccus Classical/hydatidosis/ Worldwide granulosus cystic/ unilocular echinococcosis E. multilocularis Alveolar hydatid 4 geographical disease/multilocular regions of northern echinococcosis hemisphere E. vogeli Polycystic echinococcosis Central and south E. oligarthus America

Contd..  In country, an isolated case of Alveolar Echinoccosis caused by E. multilocularis was reported from a man from the hill regions of Kashmir. [Aikat et al. 1978] But, no reservoir has yet been identified.

 Cystic Echinococcosis Chronic disease caused by expansive growth of Echinococcus cysts (metacestodes) in liver, lungs, and spleen etc. Adult worm in dogs, other canids, and large cats (lions and leopards) but rarely in house cats. All domestic can act as I.H., but major zoonotic problems occur in sheep rearing regions. Man gets involved as an accidental and dead-end host.

Contd.. In 50 to 70% human cases, cysts (metacestodes) form in liver, followed by lungs (30 to 50%), spleen and peritoneum (3 to 8%). The mean age when patients develop clinical signs is approximately 50 years.

Clinical case of Echinococcosis

Contd.. Hydatid cyst contents Positive Casoni skin test

In India, Echinococcosis is present in most of the states of which Andhra Pradesh and Tamil Nadu predominate. [Anantaraman. 1983]

Contd.. Pulmonary hydatidosis from Andhra Pradesh, Gujarat, Himachal Pradesh, Maharashtra, Rajasthan, Tamil Nadu and Uttar Pradesh were recorded. In 15-20% of patients having multiple unilocular cysts, multiple cysts have been found to be 66% in liver, 20% in lungs and 10% in other parts of the body. [Parija. 2002] In a retrospective study at PGI, Chd., a significant increase in seropositivity was observed during the 1999-2003 (23.12%) as compared with 1984-1998 (10.97%). A similar increase (33.83%) was also observed in Casoni's skin test than earlier (21.38%). [Khurana et al. 2007]

Contd.. In dogs  Prevalence ranges 3.5%  In other species, Thapliyal (1999) reported prevalence: (Amritsar) to 33% (Kurnool).  17.82-31.9% in cattle,  In Kurnool, the prevalence of  11.3-48.1% in buffaloes, infection was higher in stray  2.75-30.5% in sheep, dogs near slaughter houses  2.6-21% in in goats, compared with stray dogs away from the area [Reddy,  3-52% in swine, and D.B. et al. (1968)].  dogs 16-30%.

Singh and Dhar (1988) reported prevalence of larval E. graulosus 48.1%, 30.5% and 21% among Buffaloes, sheep and goats, respectively in northern India.

Contd..

Trypanosomiasis

Zoonotic Non-pathogenic Non-zoonotic

•Trypanosoma brucei (Sleeping sickness) T. evansi in cattle T. lewisi in rodents •T. cruzi (Chaga’s disease) zoonoses

Recently, human cases reported in India. [Powar et al. 2006; Joshi et al. 2005] Contd.. First case, 56-year-old farmer from Shivni village in Chandrapur district, Maharhashtra on 11 January, 2005; treated with Suramin and cured. The parasite was reported to be T. evansi; a vet. Practotioner. [Powar 2006, Joshi et al. 2005] Second case, 57-year-old water supplier, from Pune in May, 2007; despite the treatment he died in November, 2007. The parasite was identified as T. lewisi. No contact with cattle. [Indian Express, 2007] Third case, 2-month-old girl child from Mumbai. After treatment at Parel's Wadia hospital, Mumbai, she was declared healthy. But she is being monitored. No contact with cattle but father is a dairyman. [Kaur et al. 2007] Contd.. Giardiasis (Lambliasis) Ubiquitous flagellated protozoa Giardia intestinalis (syn. G. lamblia or G. duodenalis) causing infectious GIT disease.

These parasites are transmissible from humans to dogs and rodents and vice-versa.  Human infections-worldwide. Prevalence rates in temperate climates are 2-10% in adults and up to 25% in children; where as in tropical areas, about 50 to 80% are carriers. (Krauss et al, 2003)

Contd.. Two categories of people- young children and HIV infected adults- are particularly susceptible, [Angulo et al. 1994] In country, Peak incidences usually occur during the monsoons or in dry seasons in drought-affected areas. [Traub et al. 2004] In 11% children of acute diarrhoea cases and 15% of persistent diarrhoea in Delhi, Giardia was implicated as cause. [Rastogi et al. 1999, Kaur et al. 2002] A staggering 67% of children with recurrent were harbouring the parasite in Kashmir. [Buch et al. 2002] In tea-growing communities of Assam, 8% of humans and 20% of dogs were positive for Giardia. [Traub et al. 2004] Cryptosporidiosis  Cryptosporidium parvum species is mainly responsible for zoonotic cryptosporidiosis; widespread in mammals; in calves and lambs. A major cause of human diarrhoeal disease worldwide, especially in immunocompromised patients.  Usual transmission by Because of autoinfection by contamination with thick thin walled oocysts walled oocysts

Contd..  At CMC, Vellore, in 28 cases out of 111 HIV patients with diarrhoea, Cryptosporidial infection was identified. [Rao Ajjampur et al. 2007]

 In Madurai, South India, intestinal parasites were detected in 38.7% HIV/AIDS patients; protozoa (Entamoeba spp. 37.5%, Cryptosporidium parvum 28.7%) accounted for the majority of diarrhoea cases among these patients. [Ramakrishnan et al. 2007]

 In West Bengal, during 2003-04, in 18.51% of diarrhoeic human cases and 6.68% of non-diarrhoeic cases, Cryptosporidium had been found. [Roy et al. 2006] Leishmaniasis

Clinical syndrome (Synonym) Species Visceral leishmaniasis (Kala-azar, Leishmania donovani donovani, Dumdum fever, Assam fever, L. donovani infantum Black sickness) Cutaneous leishmaniasis (Old L. tropica minor, world leishmaniasis, Oriental L. tropica major boil, Delhi boil, Baghdad boil) Muco-cutaneous leishmaniasis L. aethiopica, (New world leishmaniasis, L. braziliensis, American leishmaniasis, L. mexicana Espundia)

 Wild animals (fox, jackal and rodents) and dogs are the major animal species involved in maintaining the natural foci of infection. Contd.. In India- 3 clinical Kala-azar Non-zoonotic; syndromes while in rest of world ‘dog’ is reservoir Post kala-azar dermal Old world leishmniasis (PKDL ) Cutaneous Both

Non-zoonotic; Zoonotic Non-zoonotic Chronic to KA Both are endemic in Rajasthan; In zoonoses, the animal reservoir was the rodent, Meriones hurricane; sand fly (Phlebotomus papatasi and/or P. salchi) was responsible for transmission of infection to man.

Contd.. The pattern is changing.  In the temperate area of H. P. (previously non-endemic area), 38 new cases of CL from 1988-2000. [Sharma et al. 2003] 161 new localized cases (May 2001- Dec. 2003) in the Kinnaur District; The new cases are increasing almost by epidemic proportions. [Sharma et al. 2005] In Rajasthan, a new focus of CL has emerged in the Ajmer city (previously non-endemic area). 23 new cases between Jan. 2004 – Dec. 2005 and 13 new cases from Jan.-Feb. 2006 have been reported . [Rastogi and Nirwan. 2007] Contd.. Cutaneous leishmaniasis

Contd.. Cutaneous leishmaniasis Mucosal leishmaniasis

Visceral leishmaniasis Post-kala-azar dermal leishmaniasis (PKDL) Toxoplasmosis

 Worldwide in humans, esp. problematic in children after congenital transmission and in opportunistic infections of immunocompromised persons.

 Studies have estimated that up to 1/3rd of world’s human population is serological positive to T. gondii. (Krauss et al., 2003)

 The encephalitis due to T. gondii infection can occur in up to 40% of HIV infected patients. [Montoya and Remington. 2000]

 Almost 200 human cases of toxoplasmosis were recorded from Coimbatore. [The Hindu. Friday, Dec.17, 2004] Contd.. Human infection: Ingestion of undercooked infected meat containing cysts Ingestion of the sporulated oocysts from contaminated hands or Organ transplantation Blood transfusion (iatrogenic) Transplacental transmission Accidental inoculation of tachyzoites in the skin

Contd.. Toxoplasma infection in humans

Immunocompetent Immunocompromised pregnancy persons

 >90% of cases Congenital infection  Acute infection. from reactivated, previously acquired,  80-90% clinical latent infection Abortion, Ocular inapparent. (tissue cysts). neonatal disease death, fetal  Mainly in brain, in adult exceptionally in the abnormalities eyes, lungs, heart, and other organs. .

Contd..  27% of women with bad obstetric history (BOH) are susceptible to toxoplasmosis in North India. [The Tribune. Sunday, Nov.9, 2003]  Meisheri et al. (1997) has reported 30.9% sero-prevalence in healthy individuals while 67.8% in HIV patients.  In the first national serological surveillance, 24.3% serum samples were IgG and 2% IgM positive by immunocapture ELISA. The lowest seroprevalences were in the northern parts of India, with the highest in the south. [Dhumne et al. 2007]  In Karnataka, Overall 20.3% sero-prevalence of T. gondii in healthy adult blood donors has been reported. [Sundar et al. 2007] Contd.. Out of 135 hospitalised HIV-patients in north India, in 3.7% cases cerebral toxoplasmosis has been reported. Other imp. infection reported was cerebral tuberculosis (71%). [Sharma et al 2004]  An outbreak of ocular toxoplasmosis, of acute acquired type rather than reactivation of congenital toxoplasmosis, has been reported in Coimbatore. [Palanisamy et al. 2006]  If maternal infection was acquired ≥6 months before conception, fetus is generally not affected. TORCH  High sero-prevalence of TO- Toxoplasmosis toxoplasmosis during TORCH R-Rubella testing in Delhi and Kinnaur areas (Kaushik, R. 2005, C- Cytomegalovirus (Thapliyal, N. 2005). H- Herpes simplex virus type 1 and 2