Leishmaniasis and phlebotomine sand flies in Oman Sultanate.

There are few data on leishmaniases and sandflies in Oman Sultanate. We carried out an eco-epidemiological study in 1998 in the two main mountains of the country, the Sharqiyah and the Dhofar. This study allowed us to isolate and identify three Leishmania strains from patients exhibiting cutaneous leishmaniasis. The typing carried out by isoenzymatic study and by molecular biology were congruent: two strains of Leishmania donovani zymodeme (Z) MON-31 isolated in the Sharqiyah and one L. tropica ZROM102 (ZMON-39 variant for 4 isoenzymes) from the Dhofar. No strain was isolated from canids. The study of sandflies identified 14 species distributed in the genera Phlebotomus, Sergentomyia and Grassomyia: Ph. papatasi, Ph. bergeroti, Ph. duboscqi, Ph. alexandri, Ph. saevus, Ph. sergenti, Se. fallax, Se. baghdadis, Se. cincta, Se. christophersi, Se. clydei, Se. tiberiadis, Se. africana, and Gr. dreyfussi. In Sharqiyah, the only candidate for the transmission of L. donovani was Ph. alexandri, but the low densities observed of this species do not argue in favor of any role. In Dhofar, Ph. sergenti is the most important proven vector of L. tropica, but Ph. saevus, a locally much more abundant species, constitutes a good candidate for transmission.

TITLE: Leishmanioses et phlébotomes au Sultanat d'Oman. ABSTRACT: Il existe peu de données sur les leishmanioses et les phlébotomes en Oman. Nous y avons mené en 1998 une étude éco-épidémiologique dans les deux principaux massifs montagneux du pays, la Sharqiyah et le Dhofar. Cette étude nous a permis d'isoler et d'identifier trois souches de Leishmania à partir de patients présentant des leishmanioses cutanées. Les typages menés par étude isoenzymatique et par biologie moléculaire ont été congruents : deux souches de Leishmania donovani ZMON-31 isolées dans la Sharqiyah et une de L. tropica ZROM102 (ZMON-39 variant pour 4 isoenzymes) originaire du Dhofar. Aucune souche n'a été isolée à partir de Canidés. L'étude des Phlébotomes a permis d'identifier 14 espèces réparties dans les genres Phlebotomus, Sergentomyia et Grassomyia : Ph. papatasi, Ph. bergeroti, Ph. duboscqi, Ph. alexandri, Ph. saevus, Ph. sergenti, Se. fallax, Se. baghdadis, Se. cincta, Se. christophersi, Se. clydei, Se. tiberiadis, Se. africana et Gr. dreyfussi. Dans la Sharqiyah, la seule espèce candidate à la transmission de L. donovani est Ph. alexandri mais les faibles densités observées de cette espèce ne plaident pas en faveur d'un quelconque rôle. Dans le Dhofar, Ph. sergenti est le principal vecteur prouvé de L. tropica mais Ph. saevus, espèce localement bien plus abondante, constitue une bonne espèce candidate à la transmission.

Effectiveness Study of Paromomycin IM Injection (PMIM) for the Treatment of Visceral Leishmaniasis (VL) in Bangladesh.

BACKGROUND: This study was conducted in Bangladeshi patients in an outpatient setting to support registration of Paromomycin Intramuscular Injection (PMIM) as a low-cost treatment option in Bangladesh. METHODOLOGY: This Phase IIIb, open-label, multi-center, single-arm trial assessed the efficacy and safety of PMIM administered at 11 mg/kg (paromomycin base) intramuscularly once daily for 21 consecutive days to children and adults with VL in a rural outpatient setting in Bangladesh. Patients ≥5 and ≤55 years were eligible if they had signs and symptoms of VL (intermittent fever, weight loss/decreased appetite, and enlarged spleen), positive rK39 test, and were living in VL-endemic areas. Compliance was the percentage of enrolled patients who received 21 daily injections over no more than 22 days. Efficacy was evaluated by initial clinical response, defined as resolution of fever and reduction of splenomegaly at end of treatment, and final clinical response, defined as the absence of new clinical signs and symptoms of VL 6 months after end of treatment. Safety was assessed by evaluation of adverse events. PRINCIPAL FINDINGS: A total of 120 subjects (49% pediatric) were enrolled. Treatment compliance was 98.3%. Initial clinical response in the Intent-to-Treat population was 98.3%, and final clinical response 6 months after end of treatment was 94.2%. Of the 119 subjects who received ≥1 dose of PMIM, 28.6% reported at least one adverse event. Injection site pain was the most commonly reported adverse event. Reversible renal impairment and/or hearing loss were reported in 2 subjects. CONCLUSIONS/SIGNIFICANCE: PMIM was an effective and safe treatment for VL in Bangladesh. The short treatment duration and lower cost of PMIM compared with other treatment options may make this drug a preferred treatment to be investigated as part of a combination therapy regimen. This study supports the registration of PMIM for use in government health facilities in Bangladesh. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01328457.

Report of the Post Kala-azar Dermal Leishmaniasis (PKDL) Consortium Meeting, New Delhi, India, 27-29 June 2012.

Post kala-azar dermal leishmaniasis (PKDL) is a neglected complication of visceral leishmaniasis (VL)-a deadly, infectious disease that claims approximately 20,000 to 40,000 lives every year. PKDL is thought to be a reservoir for transmission of VL, thus, adequate control of PKDL plays a key role in the ongoing effort to eliminate VL. Over the past few years, several expert meetings have recommended that a greater focus on PKDL was needed, especially in South Asia. This report summarizes the Post Kala-Azar Dermal Leishmaniasis Consortium Meeting held in New Delhi, India, 27-29 June 2012. The PKDL Consortium is committed to promote and facilitate activities that lead to better understanding of all aspects of PKDL that are needed for improved clinical management and to achieve control of PKDL and VL. Fifty clinicians, scientists, policy makers, and advocates came together to discuss issues relating to PKDL epidemiology, diagnosis, pathogenesis, clinical presentation, treatment, and control. Colleagues who were unable to attend participated during drafting of the consortium meeting report.

Leishmaniasis worldwide and global estimates of its incidence.

As part of a World Health Organization-led effort to update the empirical evidence base for the leishmaniases, national experts provided leishmaniasis case data for the last 5 years and information regarding treatment and control in their respective countries and a comprehensive literature review was conducted covering publications on leishmaniasis in 98 countries and three territories (see 'Leishmaniasis Country Profiles Text S1, S2, S3, S4, S5, S6, S7, S8, S9, S10, S11, S12, S13, S14, S15, S16, S17, S18, S19, S20, S21, S22, S23, S24, S25, S26, S27, S28, S29, S30, S31, S32, S33, S34, S35, S36, S37, S38, S39, S40, S41, S42, S43, S44, S45, S46, S47, S48, S49, S50, S51, S52, S53, S54, S55, S56, S57, S58, S59, S60, S61, S62, S63, S64, S65, S66, S67, S68, S69, S70, S71, S72, S73, S74, S75, S76, S77, S78, S79, S80, S81, S82, S83, S84, S85, S86, S87, S88, S89, S90, S91, S92, S93, S94, S95, S96, S97, S98, S99, S100, S101'). Additional information was collated during meetings conducted at WHO regional level between 2007 and 2011. Two questionnaires regarding epidemiology and drug access were completed by experts and national program managers. Visceral and cutaneous leishmaniasis incidence ranges were estimated by country and epidemiological region based on reported incidence, underreporting rates if available, and the judgment of national and international experts. Based on these estimates, approximately 0.2 to 0.4 cases and 0.7 to 1.2 million VL and CL cases, respectively, occur each year. More than 90% of global VL cases occur in six countries: India, Bangladesh, Sudan, South Sudan, Ethiopia and Brazil. Cutaneous leishmaniasis is more widely distributed, with about one-third of cases occurring in each of three epidemiological regions, the Americas, the Mediterranean basin, and western Asia from the Middle East to Central Asia. The ten countries with the highest estimated case counts, Afghanistan, Algeria, Colombia, Brazil, Iran, Syria, Ethiopia, North Sudan, Costa Rica and Peru, together account for 70 to 75% of global estimated CL incidence. Mortality data were extremely sparse and generally represent hospital-based deaths only. Using an overall case-fatality rate of 10%, we reach a tentative estimate of 20,000 to 40,000 leishmaniasis deaths per year. Although the information is very poor in a number of countries, this is the first in-depth exercise to better estimate the real impact of leishmaniasis. These data should help to define control strategies and reinforce leishmaniasis advocacy.

Annual incidence of visceral leishmaniasis in an endemic area of Bihar, India.

The study presents the findings of a population-based survey of the annual incidence of visceral leishmaniasis (VL) in the rural areas of one VL-endemic district in Bihar, India. Stratified multi-stage sampling was applied in the selection of blocks, villages, hamlets, and households. We screened 15 178 households (91 000 individuals) in 80 villages in 7 of 27 administrative blocks of the district, East Champaran. We identified 227 VL cases that occurred in the past 12 months: 149 treated individuals who survived, 14 who died from VL, and 64 active cases. The high-incidence stratum had an estimated incidence of 35.6 cases per 10 000 persons per year (90% CI: 27.7-45.7). The annual incidence rate in the medium stratum areas was 16.8 cases per 10 000 (90% CI: 9.3-30.6). The combined annual incidence rate for the high and medium areas combined was 21.9 cases per 10 000 per year, (90% CI: 14.0-34.2). The Government of India's VL elimination goal is to reduce the VL incidence to one case per 10 000 at the sub-district level; thus, a 35-fold reduction will be required in those areas with the highest VL incidence.

The economic impact of visceral leishmaniasis on rural households in one endemic district of Bihar, India.

OBJECTIVE: To estimate the economic burden of visceral leishmaniasis (VL) on the rural population of one VL endemic district of Bihar, the state with 85% of India's cases. METHODS: Using a survey of a stratified multistage sampling of 15 178 households with 214 individuals with VL in the previous 12 months, the study provides data on VL treatment expenditures, financing and days of work lost in the context of overall household expenditures, income sources and assets. RESULTS: Median household expenditures on VL treatment represent, on average, 11% of annual household expenditures and an estimated 7 months of an individual's income at the daily wage in rural Bihar. With 87% of households forced to take out loans to finance disease costs, VL can contribute to a spiral of increasing poverty. The current pattern of VL treatment, with multiple visits and treatments for a single episode of illness, significantly increases the economic burden on the household. CONCLUSION: India's National Elimination Program to make effective treatments accessible to the rural poor, if combined with expanded efforts to improve timely access to diagnosis by conducting rapid diagnostic tests closer to the community (and mobilizing the rural population to seek effective treatment earlier), can reduce VL's economic burden on India's rural households.

Field evaluation of FD-DAT, rK39 dipstick and KATEX (urine latex agglutination) for diagnosis of visceral leishmaniasis in northwest Ethiopia.

Three novel diagnostic tests for visceral leishmaniasis (VL), namely FD-DAT, rK39 dipstick and KATEX, were evaluated under field conditions using 101 clinical cases suspected of having VL enrolled in a trial either by active (63 patients) or passive (38 patients) surveillance. VL was confirmed in 49 patients: 35 by both aspirate smear microscopy and NNN culture, 10 by NNN culture alone and 4 by aspirate smear microscopy alone. Based on tests performed in the field, sensitivity for FD-DAT, rK39 dipstick and KATEX was determined to be 95.3% (95% CI 82.9-99.2%), 71.7% (95% CI 56.3-83.5%) and 57.4% (95% CI 42.3-71.4%), respectively. Similarly, the specificity was determined to be 62.7% (95% CI 48.1-75.5%), 82.4% (95% CI 68.6-91.1%) and 84.3% (95% CI 70.9-92.5%), respectively. A higher sensitivity of KATEX (73.9% vs. 41.7%) and higher specificity of FD-DAT (100.0% vs. 48.6%) were demonstrated under passive case detection compared with active case detection. FD-DAT is recommended for confirmation of VL diagnosis in hospital settings, whereas its use in the field will be limited to exclude VL in clinical suspects. The sensitivity of KATEX and rK39 dipstick tests needs to be improved to promote their use as first-line diagnostic tests in the field setting of northwestern Ethiopia.

Leishmania/HIV co-infections in the second decade.

Leishmania-HIV co-infection has been globally controlled in Southern Europe since 1997 because of highly active anti retroviral therapy (HAART), but it appears to be an increasing problem in other countries such as Ethopia, Sudan, Brazil or India where both infections are becoming more and more prevalent. Most of the scientific background on Leishmania/HIV co-infection has been dropped from the Mediterranean experience and although the situations among countries are not fully comparable, it is of high importance to take advantage of this knowledge. In this review several aspects of the Leishmania/HIV co-infection are emphasized viz., epidemiological features, new ways of transmission, pathogenesis, clinical outcome, diagnosis, treatment and secondary prohylaxis. An extensive review of the literature on Leishmania/HIV co-infection has allowed the inclusion of a comprehensive and updated list of bibliographical references.

Amphotericin B colloidal dispersion for the treatment of Indian visceral leishmaniasis.

BACKGROUND: In Bihar, India, where visceral leishmaniasis (VL) is hyperendemic and refractory to antimony, amphotericin B is the most effective option for the treatment of VL. Lipid formulations of amphotericin B are able to circumvent the toxic effect of conventional amphotericin B, and the total dose of these formulations can be administered over a short duration. However, cost is a major constraint in the use of lipid formulations of amphotericin B. Amphotericin B colloidal dispersion (ABCD), which is a less expensive lipid formulation, has not been tested for the treatment of VL in India. METHODS: In an open-label, randomized clinical trial, we evaluated the efficacy and safety of a 6-day course of ABCD administered to 3 different dose groups (total dose: 7.5 mg/kg [group A], 10 mg/kg [group B], and 15 mg/kg [group C]), each of which included a cohort of 135 patients. RESULTS: Although infusion-related fever and chills occurred in 56%-68% of patients in the 3 different dose groups, 401 of 405 patients completed the treatment. All 135 patients in group A completed treatment, and the final cure rate for this group was 97%. In the group that received the highest dose of ABCD (group C), severe backache, an unusual side effect, was observed in 8 patients (5.92%). Serious adverse effects led to the withdrawal of 2 patients (1.48%) each from group B and group C. CONCLUSIONS: Although the cost of ABCD is prohibitive, the high level of efficacy associated with short-term treatment with low-dose ABCD provides another alternative for the treatment of VL, especially in regions where VL is antimony refractory.

Field validity, reproducibility and feasibility of diagnostic tests for visceral leishmaniasis in rural Nepal.

OBJECTIVES: To assess the field accuracy, reproducibility and feasibility of the formol gel test (FGT), the urine latex agglutination test (KAtex) and a rK39 antigen-based dipstick for the diagnosis of visceral leishmaniasis (VL) in rural Nepal. METHOD: Patients with clinical suspicion of VL were recruited at Rangeli District Hospital (DH), a 15-bed government hospital located in south-eastern Nepal. FGT, KAtex and rK39 dipstick tests were performed on site and later repeated at a reference kala-azar diagnostic laboratory to assess reproducibility. Diagnosis of VL was confirmed by either a positive bone marrow aspirate examination or a positive direct agglutination test (DAT titre > or = 1:3200) in patients who later responded to anti-leishmanial therapy. RESULTS: Of 155 patients initially recruited, 142 (85 with VL and 57 with another diagnosis) were included in the study. The sensitivity of the rK39 dipstick [89%; 95% confidence interval (CI): 81-94] was significantly higher than that of the KAtex (57%; 95% CI: 46-67) and the FGT (52%; 95% CI: 41-62). All three tests had a specificity of at least 90%. Agreement was higher for the rK39 dipstick (kappa = 0.87) than for the FGT (0.68) and the KAtex (0.43). All tests required < or = 20 min of actual work and < or = 40 min to obtain the results. CONCLUSION: The rK39 dipstick was easy to do, more accurate and reproducible than other rapid diagnostic tests for VL in a DH of rural Nepal. It should be integrated into the field diagnostic algorithm of VL in this region and mechanisms to secure its availability should be found.

A comparative study of the effectiveness of diagnostic tests for visceral leishmaniasis.

We compared the validity of pancytopenia, the formol-gel test (FGT), the indirect fluorescence antibody test (IFAT), the direct agglutination test (DAT), and the rK39 dipstick test as diagnostic criteria for visceral leishmaniasis (VL) in Nepal. Between September 2000 and January 2002, 310 clinical suspects had a bone marrow aspirate, and if negative, a spleen aspirate smear examined for Leishmania donovani. Sensitivity and specificity of all tests were determined compared with parasitology and by latent class analysis (LCA). Compared with parasitology, the sensitivities of the other tests were as follows: pancytopenia = 16.3% (95% confidence interval [CI] = 11.3-22.5%), FGT = 39.9% (95% CI = 32.7-47.4%), IFAT = 28.4% (95% CI = 22.0-35.5%), DAT = 95.1% (95% CI = 90.8-97.7%), and the rK39 dipstick test = 87.4% (95% CI = 81.7-91.9%). Sensitivity estimates obtained by LCA were similar, but specificity estimates were substantially higher (DAT = 93.7% versus 77.8%; rK39 dipstick test = 93.1% versus 77.0%). The DAT or the rK39 dipstick test can replace parasitology as the basis of a decision to treat VL in Nepalese peripheral health services.

Strategic emphases for tropical diseases research: a TDR perspective.

Setting priorities for health research is a difficult task, especially for the neglected diseases of the poor. A new approach to priority setting for tropical diseases research has been adopted by the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (known as the TDR). Priorities are defined on the basis of a comprehensive analysis of research needs and research opportunities for each of the ten major tropical diseases in the TDR portfolio. The resulting strategic emphases matrix reflects the priorities for tropical diseases research from the perspective of the TDR. Its purpose is not to impose global research priorities, but we believe the results could be useful to other organizations.

Strategic emphases for tropical diseases research: a TDR perspective.

Setting priorities for health research is a difficult task, especially for the neglected diseases of the poor. A new approach to priority setting for tropical diseases research has been adopted by the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (known as the TDR). Priorities are defined on the basis of a comprehensive analysis of research needs and research opportunities for each of the ten major tropical diseases in the TDR portfolio. The resulting strategic emphases matrix reflects the priorities for tropical diseases research from the perspective of the TDR. Its purpose is not to impose global research priorities, but we believe the results could be useful to other organizations.

Visceral leishmaniasis: current status of control, diagnosis, and treatment, and a proposed research and development agenda.

Visceral leishmaniasis is common in less developed countries, with an estimated 500000 new cases each year. Because of the diversity of epidemiological situations, no single diagnosis, treatment, or control will be suitable for all. Control measures through case finding, treatment, and vector control are seldom used, even where they could be useful. There is a place for a vaccine, and new imaginative approaches are needed. HIV co-infection is changing the epidemiology and presents problems for diagnosis and case management. Field diagnosis is difficult; simpler, less invasive tests are needed. Current treatments require long courses and parenteral administration, and most are expensive. Resistance is making the mainstay of treatment, agents based on pentavalent antimony, useless in northeastern India, where disease incidence is highest. Second-line drugs (pentamidine and amphotericin B) are limited by toxicity and availability, and newer formulations of amphotericin B are not affordable. The first effective oral drug, miltefosine, has been licensed in India, but the development of other drugs in clinical phases (paromomycin and sitamaquine) is slow. No novel compound is in the pipeline. Drug combinations must be developed to prevent drug resistance. Despite these urgent needs, research and development has been neglected, because a disease that mainly affects the poor ranks as a low priority in the private sector, and the public sector currently struggles to undertake the development of drugs and diagnostics in the absence of adequate funds and infrastructure. This article reviews the current situation and perspectives for diagnosis, treatment, and control of visceral leishmaniasis, and lists some priorities for research and development.

Domestic and peridomestic transmission of American cutaneous leishmaniasis: changing epidemiological patterns present new control opportunities

Predictions that deforestation would reduce American cutaneous leishmaniasis incidence have proved incorrect. Presentations at a recent international workshop, instead, demonstrated frequent domestication of transmission throughout Latin America. While posing new threats, this process also increases the effectiveness of vector control in and around houses. New approaches for sand fly control and effective targeting of resources are reviewed