1 Dewi Masyithah/Par/2004 Soil – Transmitted Helminthiasis ( STH ) • nematode infections • transmitted via soil medium either 1. Ingestion of embryonated eggs 2. Skin penetration by infective larvae • refers to these helminths: Ascaris lumbricoides Trichuris trichiura Hookworms Strongyloides stercoralis Toxocara spp. Common STH agents Dewi Masyithah/Par/2004 Epidemiological situation Worldwide distribution. Frequencies of infection: Ascariasis 1,000 million Trichuriasis 900 million Hookworms 500 million Enterobiasis 400 million Strongyloidiasis 100 million Taeniasis 70 million Reported In 150 out of 208 countries In highly endemic areas, prevalence as high as 60-80%; in Latin America they affect between 20-30% of general population
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Dewi Masyithah/Par/2004
Soil – Transmitted Helminthiasis ( STH )
• nematode infections
• transmitted via soil medium either
1. Ingestion of embryonated eggs
2. Skin penetration by infective larvae
• refers to these helminths:
Ascaris lumbricoidesTrichuris trichiura
HookwormsStrongyloides stercoralis
Toxocara spp.
Common
STH
agents
Dewi Masyithah/Par/2004
Epidemiological situation
Worldwide distribution. Frequencies of infection:
Ascariasis 1,000 million
Trichuriasis 900 million
Hookworms 500 million
Enterobiasis 400 million
Strongyloidiasis 100 million
Taeniasis 70 million
Reported In 150
out of 208 countries
In highly endemic areas, prevalence as high as 60-80%;
in Latin America they affect between 20-30% of general
population
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Dewi Masyithah/Par/2004
Infections STH associated with:
• Poverty and poor condition
• Inadequate sanitation and water supplies
• Soil quality and climate
• Poor personal and environmental hygiene
• Poor health awareness
Dewi Masyithah/Par/2004
Habitat of STH in host
Large intestine
Small intestine
Trichuris trichiura
Ascaris lumbricoides
Hookworms
Strongyloides
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Morphology of adult STH
Large, cylinder, tapers at both
ends
Size 200-400 mm x 2-3 mm
Long, slender, coiled
posterior (male) and
whip-like
Size 30-50 mm
Tiny, short
Size 5-13 mm
Ascaris Trichuris Hookworms
Dewi Masyithah/Par/2004
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Dewi Masyithah/Par/2004
Ascariasis
Etiology: Ascaris lumbricoides ( roundworm )
Habitat : small intestine, especially jejunum and upper ileum
Dewi Masyithah/Par/2004
Life cycle of
Ascaris
lumbricoides
Infective stage
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Clinical presentations
Migration of
larvae in
circulation �
respiratory tree
Adult worms in
small intestine
• Loeffler’s syndrome
• inflammation in brain,
heart, kidneys, spinal
cord
• blockage
• malnutrition
• allergy
• ectopic
(wanderlust)
Dewi Masyithah/Par/2004
Pathology caused by Ascaris lumbricoides
• malnutrition due to absorption of nutrients in small intestine as
food passes.
• majority symptomless
• intestinal obstruction followed by infarction and gangrene
• acute and chronic inflammation with infiltrations by eosinophils,
histiocytes and mononuclear cells at sites of ectopic ascariasis
• granuloma formation around ova in tissues
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• Malnutrition due to Ascariasis:
One adult worm: 0.14 g carbohydrate daily
0.035 g protein daily
One gram of rice contains ± 0.8 g carbohydrate.
We assume ± 4 adult worm in human body for example.
Indonesian people: ± 200 million; ± 560 million adult
worm.
We will lose carbohydrate: ± 76,440 Kg of rice.
One gram of meat contains 0.18 g protein.
One adult worm absorb ~ 424 cows (á 200 Kg).
Dewi Masyithah/Par/2004
Diagnosis
Adult worm out of body openings
Larvae std 3rd in sputum
Eggs in feces – fertilized / unfertilized
Serology for extraintestinal ascariasis (?)
Control
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Dewi Masyithah/Par/2004
Ways to improve………..
A. Short term:
Mass anti-helminthic drug administration.
Ideal condition 0f
helminthic drugs:1. Cheap
2. Available3. Less additional effect4. Broad spectrum5. Germicidal & larvacidal6. Single dose
Treatment:
- Pyrantel pamoate 10
mg/kg stat dose.
- Mebendazole 500mg daily
- Piperazine citrate 75 mg/kg
x 2 days
- Albendazole 400 mg stat
dose
Dewi Masyithah/Par/2004
1 Improve sanitation: providing proper toilet
B: Long term:
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Health education
Ways to improve ……
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Dewi Masyithah/Par/2004
Health education
Ways to improve ……
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Dewi Masyithah/Par/2004
Trichiuriasis
Etiology: Trichiuris trichiura ( whipworm )
(trichuris = hairtail; trichocephalus = hairhead)
Habitat: large intestine, especially cecum and vermiform appendix
Dewi Masyithah/Par/2004
Adult Trichuris
Female
- larger
- whip-like
Male
- coiled
posterior
Anterior end
3/5 body length
Posterior end
2/5 body length
Contain intestine, reproductive organs
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Dewi Masyithah/Par/2004
Trichuris eggs
Eggs in fresh feces
- barrel shaped
- mucus plugs at both ends
- unsegmented ovum
Eggs in external environment
- similar characteristics
- embryonated larva inside!
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Life cycle of
Trichuris trichiura
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Clinical presentations
• LOW
• anemia
• bloody diarrhea
• malnutrition
• anorectal prolapse
• 2nd bacterial / protozoal infections
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Pathology caused in Trichuriasis
Anterior portion of worm embedded in intestinal mucosa of large
intestine and cause petechial hemorrhages � anemia
Breaks and lesions in mucosa predispose to secondary bacterial