Blood Trematodes

Isna IndrawatiDepartment of Parasitology

SCHISTOSOMA JAPONICUM SCHISTOSOMA MANSONI SCHISTOSOMA MEKONGISCHISTOSOMA INTERCALATUMSCHISTOSOMA HAEMATOBIUM

Schistosoma

WHO fact sheet (2012) :230 million infected people are require

treatment yearly.Schistosomiasis transmission has been

documented in 77 countries.90% of those requiring treatment for

schistosomiasis live in Africa.In sub-Saharan Africa: > 200 000 deaths

per year are due to schistosomiasis.

Schistosoma

Belongs to Platyhelminthes.Have separate sexes. Live in venule of mesenteric / plexus

vesicalisRequire one intermediate host to

complete their life cycleLife cycle and pathological effect nearly

the same

Species Geographical distribution

Intestinal schistosomiasis Schistosoma mansoni

Africa, the Middle East, the Caribbean, Brazil, Venezuela, Suriname

Schistosoma japonicum China, Indonesia, the Philippines

Schistosoma mekongiSeveral districts of Cambodia and the Lao People’s Democratic Republic

Schistosoma guineensis and related S. intercalatum

Rain forest areas of central Africa

Urogenital schistosomiasis

Schistosoma haematobium Africa, the Middle East

S.Japonicum S. mansoni S. haemato

bium

Distribution

Asia: China, Indonesia, the Philippines

Africa, South America

DiseaseOriental Schist.is Katayama disease, snail fever

Manson’s intestinal schist. is

Definitive Host

Human, dog, cat, rat, cattle ect.

Human, Monkey

Intermediate host

Oncomelania Biomphalaria

Habitat V. Mesenterica superior V. Mesenterica inferior

OnchomelaniaBiomphalaria

S. mansoni

S.Japonicum S. mansoni S.haematobium

Adult:- Male- female

1.2 – 2 cm2.6 cm

0.6 – 1.2 cm1.2 – 1.7 cm

Body surface The cuticle of the

male is covered with fine spines

The cuticle of the male is covered with minute papillae.

Testes 7 testes 6-9 testes

Eggs 70-100 x 50-65 µ , oval, lateral knob

114-175x 45-68 µ, elongate, lateral spine

Pathogenesis and clinical symptoms

Infection : penetration of cercaria through the skin pruritic skin rash (swimmer's itch within 24 hours post infection

During incubation period: General : malaise, headache, nauseaAllergic rx to metabolite : urticaria ,

angio-neurotic edema, feverLung: cell infiltration and haemorrhage

Cercarial / swimmers’s itch

Clinical symptoms

Acute : usually 4-8 weeks after contact with infested water

Fever , fatigueabdominal pain, When egg deposition : gastro intestinal

complaints, diarrhoea (dysentery).Symptoms : >> are caused by the

body's reaction to the worms’ eggs

Adult worms may produce 300 to 3000 eggs per day.

Many of the eggs pass through the intestinal wall into the feces.

carried in blood and become trapped in, gastro-intestinal, the liver , lungs and brain etc.

Eggs of Schistosoma trapped in the intestinal wall and liver

eggs that carried in bloodtrapped in liver, lungs, and brain

rx granuloma surrounding eggs

pseudo tubercle in the liver / organs

fibrosis

Chronic :

90 % patients are in chronic stage. weakness, fatigue, abdominal pain Liver enlargement Portal hypertension of the abdominal

blood vessels.Splenomegali

Occasionally central nervous system lesions occur: cerebral granulomatous disease may be caused by ectopic S. japonicum eggs in the brain,

Ascites : an accumulation of fluid in the peritoneal cavity

Source : twmrf.com

Terminal / late stage :

Cirrhosis Abdominal collateral vein dilatation ,

oesopahago-gastric variceslower limb edema, hematemesis, and melena

DIAGNOSIS

detection of parasite eggs in stool or tissues biopsy

In chronic stage: difficult to find eggs in the stool

serological/ immunological test : may be useful in the detection of infection.

Diagnosis (cont’d)

Elisa, COPT, IHA

COPT

Epidemiology

People are at risk of infection : activities which expose them to infested water.

Prevention and Control : preventive treatment snail control, improved sanitation health education

Epidemiology (cont’d)

In Indonesia : endemic in Danau Lindu and Lembah Napu, Central of Sulawesi

Integrated control started in year 2000, ( mass treatment and snail control

Mass treatment using praziquantel was held every 6 months.

Epidemiology (cont’d)

Difficult in controlling the disease : zoonotic disease ( prevalence in Rattus spp. 0 to 20% )

in Indonesia : transmission still occured in 2006 : prevalence 0.49% in Danau

Lindu and 1.08% in Lembah Napu ( in1973: 73 %)

Epidemiology (cont’d)

needs for power and water, often result in environmental modifications

Treatment should be complemented with health education, as well as access to safe water and good sanitation.

Thank you