Control of visceral leishmaniasis, southern Sudan

Situation:

Visceral leishmaniasis is a parasitic disease transmitted by sandflies. In terms of global burden, the leishmaniases are the third most important vector-borne disease after malaria and sleeping sickness with an estimated 2.4 million Disability-Adjusted Life Years and 57,000 deaths annually; the latter are exclusively caused by visceral leishmaniasis, so called kala-azar. This disease mainly affects children below the age of 15 and is characterized by irregular bouts of fever, substantial weight loss, swelling of the spleen and liver, and anaemia. If left untreated, the fatality rate of visceral leishmaniasis lies between 90-100%. Although the disease is endemic in more than 60 countries throughout the Neotropics, approximately 90% of all cases occur in only five countries - Bangladesh, Brazil, India, Nepal and Sudan. In Sudan visceral leishmaniasis is of major public health importance, killing thousands of people every year and tens or even hundreds of thousands during epidemics. Control efforts have been patchy and intermittent, usually in response to epidemics. Large, endemic foci thus exit in the east and south of the country, some of which have seen little efforts at control. The lack of control is particularly apparent in southern Sudan, which after decades of conflict has now entered a period of relative peace and is undergoing reconstruction. Most health care in southern Sudan is provided by non-governmental organisations, many of which have little or no specific technical expertise related to visceral leishmaniasis and thus do not provide case-management. This means that diagnosis and treatment are limited to a few specialised facilities, leaving a a large proportion of the affected population with limited or no access to treatment. The underlying reservoir of infected and infectious individuals is thus considerable, as is the risk of epidemics. This risk is exacerbated by the changing population dynamics that result from the returning political stability in southern Sudan, with susceptible or infected populations moving into visceral leishmaniasis endemic or non-endemic areas, respectively, In this context, commodity support and training on case-management, health education and on the appropriate use of preventative measures is essential, as is the targeted distribution of long-lasting insecticide-treated nets (LLINs).

Response:

To support visceral leishmaniasis control in some of the endemic areas of southern Sudan, the Malaria Consortium was awarded funding from the common humanitarian fund. Work is now being carried out in the northern counties of Jonglei state, as well as at in the referral centre at Malakal teaching hospital, Upper Nile state. Activities are being developed in close collaboration with the Federal and State Ministries of Health, as well as the World Health Organization in Juba, to ensure that interventions are integrated into existing health infrastructure and strengthen national capacity to respond to visceral leishmaniasis. The overall aim is to improve the referral system, though training on case management and commodity support, while also advancing the knowledge of affected communities so that symptomatic individuals report as early as possible. In addition, targeted distribution of LLINs and behaviour change education will ensure the availability and appropriate use of personal protection, thus reducing transmission of leishmaniasis within households and communities. Distribution of LLINs is currently hampered by extensive flooding in the target areas, and has thus been scheduled for late 2007, once water levels have subsided.

Points to note:

The response to visceral leishmaniasis in southern Sudan remains inadequate, despite ongoing and planned work by Malaria Consortium and a number of other partners. The limited available data indicates that the current case load is relatively low, though it is unclear what proportion of leishmaniasis cases presently fails to report to health facilities for treatment, because they are often aware that diagnostic and drug supplies are seldom available. Past experience has shown that the present situation could quickly escalate to epidemic proportions.

Forthcoming publications:

Reithinger R, Brooker S, Kolaczinski J (2007) Visceral leishmaniasis in eastern Africa - current status. Transactions of the Royal Society of Tropical Medicine and Hygiene [already available as e-publication]