| |
Site Navigation
|
 |
|
SCHISTOSOMIASIS OR BILHARZIA:
An Infection with Blood Flukes
Prince William has
returned from his summer sojourn in Africa with one of the continent's most common disease, which in the 19th century helped to earn parts of Africa the title of 'The White Man's Grave'. He caught schistosomiasis or Bilharzia, an infection with blood flukes. Flukes are parasitic flatworms, and in case of the bilharzia, caught by William, the life cycle of the schistosoma is shared with water snails. He will have picked it up either from, being splashed or swimming in, contaminated water, or from walking with exposed feet or legs in damp waterside grass where the snails have flourished. Bilharzia was, and still is, the cause of much chronic ill health in many parts of the world, but those who have been broght up with it seem to develop some resistance. The public health problem that bilharzia poses over the African continent, and in parts of the Middle East and India remains. Varieties of schistosomiasis are also found in Asia and South America, but it is absent from Canada and the United States, as the particular varieties of snail that are part of its life cycle are absent. Without the snail as an intermediary host, infection does not occur, so there is no danger that William will have infected others in the United Kingdom. The adult flukes live and breed in the blood vessels surrounding the patient's bladder or gut. Some of the eggs penetrate the wall of the bladder or the intestine and are excreted. The eggs which lodgein the bladder or intestinal wall can set up chronic inflammation which can give rise to ulceration and bleeding, either in the urine or in the feces. As the ulcers heal they can leave scars and fibrosis.In time, the persistent irritation from the inflammation can give rise to the formation of papillomas which may later turn malignant. These are the effects of chronic schistosomiasis. ACUTE SCHISTOSOMIASIS (as in William's Case). About two to four weeks after exposure, patients develop flu-like symptoms - always known as general malaise, headaches, joint pains, nausea, sometimes a fever and frequently abdominal pain.Blood tests are positive for antigens, and one particular type of white blood cell, the eosinophils, shows a marked increase. It is difficult to find a parasitic eggs. When the eggs, instead of lodging in the guts or bladder wall, find their way to the centralnervous system where, if in the brain, they can cause seizure, or if in the spine, paralysis.
TREATMENT:
Biltricide praziquantel
A revolutionary medication, discovered within the past 20 years has become the drug of choice to treat most types of schistosomiasis. The drug is given as three doses on the same day. The blood is later checked to assess the response. These tests need to be repeated after six months to make certain that a good result has been obtained. A cure rate of up to 90% is achieved by the first doses, and even in those who are not completely cured, the egg count is reduced by 90%. These patients will need re-treating with a larger, longer dose regime. Patients who are recurrently exposed need annual screening.
Mary Wilson MD
(October 31, 2003, The TIMES)
-->
return to menu / back ... (click)
--> return to top of the page (click)
|
|
