14 Water for Life
Blood flukes (Schistosomiasis, bilharzia)
This infection is caused by a kind of worm that gets into the bloodstream after
washing or swimming in contaminated water. The illness can cause serious damage to
the liver and kidneys, and may lead to death after months or years.
Sometimes there are no early signs. A common sign in some areas is blood in the
urine or bloody stools. In areas where this illness is very common, people with only
mild signs or belly pain should be tested.
Blood flukes spread like this:
1. Infected person urinates
or defecates in water.
2. Urine or feces has
worm eggs in it.
5. In this way, someone who washes
or swims in water where an infected
person has urinated or defecated
also becomes infected.
3. Worm eggs hatch,
and worms go
into snails.
4. Young worms leave
snail and go into
another person.
To treat blood flukes
Blood flukes are best treated with medicines. To know which medicines to use,
see a health worker or a general health book like Where There is No Doctor.
To prevent blood flukes
Blood flukes do not spread directly from person to person.
Part of their life they must live inside a certain kind of small
water snail. To prevent schistosomiasis, programs can be
established to kill these snails. These programs can only
work if people follow the most basic preventive step: never
urinate or defecate in or near water.
Snail