Leishmaniasis

Aetiology
This is caused by the protozoon leishmania donovani.

Distribution
Throughout tropical Africa and in parts of South America, central and east Asia. Examples of distribution relevant to travellers from Britain are that the systemic form occurs in the costal regions of the Mediterranean, north east India and central China and the cutaneous form occurs in Pakistan and Bangladesh.

The vector
The bite of the infected sandfly (Phlebotomus).

The illness
After a few weeks to a few months fever, malaise, lymphadenopahty, hepatosplenomegaly and anaemia occur in the systemic form (kala-azar). Death follows quickly if untreated. Mild forms do occur. In the cutaneous form a chronic ulcerating skin lesion forms over several months. There is no systemic illness.

Diagnosis
Usually clinically or by identification of parasites. Serology may be helpful.

Treatment
Parenteral pentavalent organo-antimony is the usual treatment. It can be toxic and must be given under specialist supervision.

Prevention is through avoiding sand-fly bites.

Recommended for more information:
'Lecture Notes in Tropical medicine'. Dion R. Bell. Blackwell Publications ISBN 0-632-02445-0 or ' Mansons textbook of Tropical Diseases' Ed.G.C.Cook WB Sanuders Company Ltd ISBN 0-7020-1764-7.