2. • Zoonotic disease
• Two parasites: T. solium and T.
saginata.
• Classified as cyclo-zoonoses.
• T. saginata – highly endemic in south
of Sahara, Eastern mediterranean and
parts of USSR. India comes under
moderate prevalence.
• T.solium- endemic in many countries
of Latin America, Africa and Asia.
Endemic in India.
3.
4.
5. Epidemiological determinants
• T.saginata and T.solium pass their life cycle in
2 hosts.
• Adult parasites lives in man’s small intestine.
Larval stage of T. saginata is found in cattles
while that of T.solium in pigs.
• Can lead to muscular, ocular and cerebral
cysticercosis.
6. Epidemiological determinants
• Mode of transmission:
– Through ingestion of larvae in undercooked beef.
– Through ingestion of food, water and vegetables
contaminated with eggs.
– Reinfection by transport of eggs from bowel to
stomach. (very rare)
Incubation period: 8 to 14 weeks
7.
8. Clinical features
• Vast cases they do not lead to clinical illhealth.
• Abdominal discomfort, anorexia and chronic
ingestion.
• May occasionally cause appendicitis or
cholangitis.
• Most serious risk of T. solium infection is
cysticercosis.
9. HUMAN CYSTICERCOSIS
• Human infection is caused by the ingestion of
eggs.
• The eggs disintegrate and infective stages leave
the intestine via hepatic portal system and are
dispersed throughout the body.
• Cysticerci that develop in nervous system is a
serious threat to individual and community.
• Variety of pathological changes lead to epilepsy,
intracranial hypertensive syndrome, psychiatric
diseases and death
10.
11. Control measures
• Treatment of infected persons.
• Meat inspection
• Health education
• Adequate sewage treatment and disposal
• Surgical removal of symptom producing cysts
• Hand washing
• Improvement of living conditions.
• Treatment of sewage used for farming
12. TREATMENT
• Praziquantel – 10mg/kg body wt. cure rate is
99%. Minimal side effects.
• Niclosamide- single dose of 4 tablets i.e. 2gm.
Given empty stomach in morning.
• Give moderate purgative 2-3hrs to eliminate
segments and eggs from bowels to avoid
possibility of cyticercosis. (in case of T.solium)
13. TREATMENT FOR CYSTICERCOSIS
• Should be individualized. Based on no. of
cysts.
• Albendazole and praziquantel.
• 400mg albendazole twice daily with fatty
meal.
• Duration of treatment may vary.
• Can be repeated.
• Praziquantel – thrice daily 50mg/kg/day for
15days.
15. • Zoonoses- group of cestodes infections
• Disease is caused by metacystode
stage (infective larva) of canine
intestinal tapeworm Echinococcus.
• Adult worms are found in dogs and
other carnovores.
• Found in sheep raising countries-
Australia, New –zealand etc.
• Highest prevalence is seen in India in
Andhra Pradesh and Tamil Nadu.
16. EPIDEMIOLOGICAL
DETERMINANTS
• Agent factors: echinococcus species. No. of
proglottids varies from 2 to 6 .
• E. granulosus: maintained in domestic cycle.
• E.multilocularis: restricted to Northern
hemisphere.
• E.oligarthus: occurring in Central and South
America and suspected to cause disease in
man.
• E. vogeli: causes polycystic hydatidosis
17. LIFE CYCLE
• Adult tapeworm lives in intestine of dogs for 2
to 4 yrs.
• Eggs are voided in feces which contaminate
soil and drinking water.
• Sheep,goats, cattles get infected after feeding
on infected vegetations.
• Eggs hatch in intestine and larvae penetrate
intestinal lining and migrate to other organs
• They lodge themselves into liver, lungs and
brain and develop into hydatid cysts
18. LIFE CYCLE
• Cycle is completed when dog ingest the
hydatid cysts.
• Dogs began to pass eggs in 7 weeks after the
ingestion.
• Man doesn’t harbor the adult worm.
19.
20. MODE OF TRANSMISSION
• By ingestion of eggs of Echinococcus with food
vegetables or water contaminated with feces
of infected dogs.
• Infection may occur while playing or handling
with dog.
• By inhalation of the dusts contaminated by
the infected eggs.
• Disease is not transmissible from person to
person.
21. CLINICAL FEATURES
Incubation period varies from months to years
depending upon number and location of cysts.
• Cysts grow slowly from 5 to 20 years before they are
diagnosed.
• Cysts are filled with watery fluid and contain large
number of tapeworm heads.
• Cysts of smaller size are generally asymptomatic.
• Large cysts causes pressure symptoms (jaundice in
liver cysts).
• In vital organs they may cause sever symptoms and
death
22. CLINICAL FEATURES
• It has been estimated that 70% of the cysts become
located in the right lobe of the liver, and rest in lungs,
brain, peritoneum, long bones and kidney.
23. DIAGNOSIS
• Clinical : based on history of residence in endemic
area. Close association with dogs
• X-ray: location of the cyst is confirmed
• Serological test: ELISA, immunofluoroscent test.
• Intradermal (Casoni) test is still widely used because
of its simplicity to perform. But this often lacks
specificity.
24. Treatment
• No specific treatment, except surgical removal of
cysts.
• Mebendazole can also be given. Tests are still on.
25. Treatment
• Preventing dogs from gaining access to raw meat at
slaughter houses- proper meat inspection and
destruction of infected viscera.
• Control of Dogs: elimination of stray dogs, dog
registration system, surveillance of dogs based on
periodic stool examination.
• Single dose of praziquantel -5mg/kg will remove
adult worms from dogs.
• Health education: particularly to butchers, dog
owners, animal breeders and shepherds etc.
