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VCWASH Cluster – Emergency Training

Vector ControlModule 1D

Schistosomiasis

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VCWASH Cluster – Emergency Training

Schistosomiasis distributionWorldwide: 200 million people infected

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VCWASH Cluster – Emergency Training

Snails

Miracidia

Cercariae

Life cycle Schistosome eggs

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VCWASH Cluster – Emergency Training

Worms swim to peoples feet and burrow in!

Intermediate host snails: A Bulinus transmits Schistosoma haematobium

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VCWASH Cluster – Emergency Training

Schisto exposure

Washing clothes in a pond containing intermediate host snails, a source of schisto infection.

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VCWASH Cluster – Emergency Training

Water project dangers

After the Navrongo irrigation dam (Ghana) was built, the incidence of schistosomiasis increased dramatically up to 87% prevalence.

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VCWASH Cluster – Emergency Training

Symptoms of Schistosomiasis• abdominal pain• diarrhoea• blood in the stool or urine• liver enlargement is common in advanced cases

• In women, urogenital schistosomiasis may present with genital lesions, vaginal bleeding, pain during sexual intercourse and nodules in the vulva. In men, urogenital schistosomiasis can induce pathology of the seminal vesicles, prostate and other organs.

• In sub-Saharan Africa, more than 200 000 deaths per year are due to schistosomiasis.

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VCWASH Cluster – Emergency Training

Control measures (1)• Drugs to reduce number of eggs in

infected person

• Reduce snail population

• Reduce release of eggs from snails

• Engineer ways to reduce the need for contact with water

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VCWASH Cluster – Emergency Training

Control measures (2)• Hygienic disposal of faeces

• Molluscocides can be used to control schito

• Grass cutting on river edges can be effective for controlling schistosomiasis snails

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VCWASH Cluster – Emergency Training

Control

• Environmental control

• Mollusciciding