We conducted a case-control study to evaluate risk factors for visceral leishmaniasis during an epidemic in a previously unaffected district of Ethiopia. We also collected blood and bone marrow specimens from dogs in the outbreak villages. In multivariable analyses of 171 matched case-control pairs, dog ownership, sleeping under an acacia tree during the day, and habitually sleeping outside at night were associated with significantly increased risk. Specimens from 7 (3.8%) dogs were positive by immunofluorescent antibody test (IFAT) and both enzyme-linked immunosorbent assays (ELISAs), whereas Leishmania DNA was detected in 5 (2.8%) bone marrow aspirates (from 3 seropositive and 2 seronegative dogs). Insecticide-treated nets may only protect a portion of those at risk. Further research on the vectors, the role of the dog in the transmission cycle, and the effect of candidate interventions are needed to design the best strategy for control.

We compared an rK39 dipstick rapid test (Amrad ICT, Australia) with a direct agglutination test (DAT) and splenic aspirate for the diagnosis of kala-azar in 77 patients. The study was carried out under field conditions in an endemic area of north-east Sudan. The sensitivity of the rK39 test compared with splenic aspiration was 92% (46/50), the specificity 59% (16/27), and the positive predictive value 81% (46/57). Compared with the diagnostic protocol used by Médecins sans Frontières, the sensitivity of the rK39 test was 93% (50/54), the specificity 70% (16/23), and the positive predictive value 88% (50/57). Compared with splenic aspirates, the sensitivity of a DAT with a titre > or =1:400 was 100% (50/50), but its specificity only 55% (15/27) and the positive predictive value was 80% (50/62). Using a DAT titre > or =1:6400, the sensitivity was 84% (42/50), the specificity 85% (23/27) and the positive predictive value 91% (42/46). All four patients with DAT titre > or =1:6400 but negative splenic aspirate were also rK39 positive; we consider these are probably 'true' cases of kala-azar, i.e. false negative aspirates, rather than false DAT and rK39 seropositives. There were no false negative DATs (DAT titre < or =1:400 and aspirate positive), but there were four false negative rK39 tests (rK39 negative and aspirate positive). The rK39 dipstick is a good screening test for kala-azar; but further development is required before it can replace the DAT as a diagnostic test in endemic areas of the Sudan.

BACKGROUND: In East Africa, visceral leishmaniasis (VL) is endemic in parts of Sudan, Ethiopia, Somalia, Kenya and Uganda. It is caused by Leishmania donovani and transmitted by the sandfly vector Phlebotomus martini. In the Pokot focus, reaching from western Kenya into eastern Uganda, formulation of a prevention strategy has been hindered by the lack of knowledge on VL risk factors as well as by lack of support from health sector donors. The present study was conducted to establish the necessary evidence-base and to stimulate interest in supporting the control of this neglected tropical disease in Uganda and Kenya. METHODS: A case-control study was carried out from June to December 2006. Cases were recruited at Amudat hospital, Nakapiripirit district, Uganda, after clinical and parasitological confirmation of symptomatic VL infection. Controls were individuals that tested negative using a rK39 antigen-based dipstick, which were recruited at random from the same communities as the cases. Data were analysed using conditional logistic regression. RESULTS: Ninety-three cases and 226 controls were recruited into the study. Multivariate analysis identified low socio-economic status and treating livestock with insecticide as risk factors for VL. Sleeping near animals, owning a mosquito net and knowing about VL symptoms were associated with a reduced risk of VL. CONCLUSIONS: VL affects the poorest of the poor of the Pokot tribe. Distribution of insecticide-treated mosquito nets combined with dissemination of culturally appropriate behaviour-change education is likely to be an effective prevention strategy.

We evaluated lymph node aspiration (LNA) as a simple diagnostic procedure for visceral leishmaniasis (VL). Lymph node aspiration was compared with the direct agglutination test (DAT) using a diagnostic titer > or = 1:6,400 in 7,880 suspected VL patients in eastern Sudan. Compared with DAT, LNA had a sensitivity of 65.1% (95% confidence interval = 63.5-66.6%). Parasite density in LNA correlated strongly with DAT titers (P < 0.0001), and low parasite density accounted for 78.1% of positive LNA results with DAT titers < 1:6,400 (n = 782). Risk factors predictive of a positive LNA result were an age of 1-29 years, male sex, a hemoglobin level < 10.0 g/dL, a DAT titer > or = 1:800, and a location with a higher prevalence of VL. Lymph node and splenic aspirations were similarly accurate as tests of cure after treatment of 50 VL patients in southern Sudan. Pre-treatment LNA results were negative in 20 cases of severe post kala-azar dermal leishmaniasis.

OBJECTIVE: To evaluate the accessibility of visceral leishmaniasis (VL) treatment. METHOD: Community-based study using in-depth qualitative interviews and focus group discussions with key informants, as well as quantitative questionnaires with 448 randomly selected heads of households in nine representative villages in three geographical sub-regions. RESULTS: Despite the high incidence of the disease, most people in Gedaref State know little about VL, and help at a treatment centre is usually sought only after traditional remedies and basic allopathic drugs have failed. Factors barring access to treatment are: lack of money for treatment and transport, impassability of roads, work priorities, severe cultural restrictions of women's decision-making power and distance to the next health center. CONCLUSIONS: To provide more VL patients with access to treatment in this highly endemic area, diagnostic and treatment services should be decentralized. Health education would be a useful tool to rationalise people's health-seeking behaviour.

Visceral leishmaniasis (VL) was known to be endemic in Somalia along the basins of the (Middle) Shebelle and (Lower) Juba rivers, and in Kenya in parts of the Rift Valley, on the border with Uganda and the Eastern Provinces. From May 2000 to August 2001, we diagnosed 904 patients with VL. The patients came from an area which spanned the Wajir and Mandera districts of north-eastern Kenya, southern Somalia, and south-eastern Ethiopia. Small numbers of patients were also seen in northern Somalia. These areas were either previously non-endemic for VL, or had only sporadic cases prior to the epidemic. We describe the features of the outbreak and review the history of VL in the region. Unusual rainfall patterns, malnutrition, and migration of a Leishmania-infected population seeking food and security may have contributed to this outbreak.

Since 1989, Médecins Sans Frontières (MSF) has provided medical humanitarian assistance during outbreaks of visceral leishmaniasis (VL; kala-azar) in Sudan. First, in western Upper Nile in southern Sudan, where a VL epidemic occurred after the resumption of the civil war in Sudan in 1983, with an estimated 100,000 deaths. Later, MSF started interventions in eastern Upper Nile and Gedaref State. In these two endemic regions VL incidence has risen markedly since 2001, which could be the start of a new epidemic cycle. Outbreaks of VL in Sudan remain unpredictable, and access to affected populations in war-torn southern Sudan is often hampered by insecurity. Therefore, MSF takes a flexible approach, establishing treatment centres where patients can be accessed. From 1989 to 2002, MSF treated >51,000 VL cases in Sudan. Despite very basic field conditions, high cure rates of 95% are being achieved. Lack of diagnostics is a major obstacle to treatment, especially during epidemic situations. Therefore, development of simple and rapid technologies is required, allowing reliable diagnosis under field conditions. For treatment of VL there is a limited choice of effective, affordable drugs. There are strong indications of an emerging resistance to antimonials in Malakal. Introduction of combination therapies is urgently needed to prevent the further emergence and spread of resistance to antimonials, which are still the mainstay of VL treatment in eastern Africa. Experience with combination therapy with sodium stibogluconate (SSG) and paromomycin is promising, and combinations of SSg with liposomal amphotericin B and miltefosine are currently being explored.

BACKGROUND: There are few reports describing the epidemiology of visceral leishmaniasis (VL) in Somalia. Over the years 2002 to 2005, a yearly average of 140 patients were reported from the Huddur centre in Bakool region, whereas in 2006, this number rose to 1002 patients. Given the limited amount of information on VL and the opportunity to compare features with the studies done in 2000 in this part of Somalia, we describe the epidemiologic and clinical features of patients who presented to the Huddur treatment centre of Bakool region, Somalia, using data routinely collected over a five-year observation period (2002-2006). METHODOLOGY: Methods used included the analysis of routine data on VL cases treated in the Huddur treatment centre, a retrospective study of records of patients admitted between 2004 and 2006, community leaders interviews, and analysis of blood specimens taken for parasite species identification in Antwerp Institute of Tropical Medicine. PRINCIPAL FINDINGS: A total of 1671 VL patients were admitted to the Huddur centre from January 2002 until December 2006. Nearly all patients presented spontaneously to the health centre. Since 2002, the average patient load was stable, with an average of 140 admissions per year. By the end of 2005, the number of admissions dramatically increased to reach a 7-fold increase in 2006. The genotype of L. donovani identified in 2006 was similar to the one reported in 2002. 82% of total patients treated for VL originated from two districts of Bakool region, Huddur and Tijelow districts. Clinical recovery rate was 93.2% and case fatality rate 3.9%. CONCLUSIONS: After four years of low but constant VL case findings, a major increase in VL was observed over a 16-month period in the Huddur VL centre. The profile of the patients was pediatric and mortality relatively low. Decentralized treatment centers, targeted active screening, and community sensitization will help decrease morbidity and mortality from VL in this endemic area. The true magnitude of VL in Somalia remains unknown. Further documentation to better understand transmission dynamics and thus define appropriate control measures will depend on the stability of the context and safe access to the Somali population.