Leprosy

Leprosy is due to infection with the bacterium Mycobacterium Leprae. It is spread through infected nasal secretions from patients with the lepromatous form of disease which occurs in only about 5% of cases.

Distribution
Widespread in Asia and also in Africa and South America. Occasional cases occur elsewhere.

WHO estimated cases (1997)
India 680,000, Brazil 105,744, Indonesia 50,000, Myamar 24500, Nigeria 21500, Congo Democratic Republic 15000, Nepal 15000, Mozambique 14800, Ethiopia 14000, Madagascar 10000, Sudan 10000, Philippines 9600, Cambodia 6000, Tanzania 5000, Guinea 4500.

Natural History
Following infection there is a usually a prolonged incubation period of 5-10 years. Those with 'lepromatous' disease normally have numerous bacilli in their skin and nasal mucosae. It is not normally possible to demonstrate bacilli in 'Tuberculoid' cases.

The illness
The classical skin lesion is an anaesthetic depigmented patch. Nerve palsies occur, usually mononeuropathies in 'tuberculoid' disease and peripheral neuropathy in 'lepromatous' disease.

Treatment
Multidrug treatment inhibits the development of drug resistance and rapidly makes lepromatous cases 'non-infectious.

Risk to travellers
This is small except for those working closely with untreated lepromatous patients who should be aware of the risk and have regular health checks.