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WHO/C. Black NEGLECTED TROPICAL DISEASES Leishmaniasis is a neglected tropical disease caused by protozoan parasites belonging to the genus Leishmania that are transmitted through the bites of sandflies. It comprises a group of infections with important clinical and epidemiological diversity spread across 98 countries in Africa, Asia, Europe and the Americas. The global burden of these infections combined is estimated to be millions of disability-adjusted life years. Approximately 200,000 to 400,000 cases of visceral leishmaniasis (VL) and 700,000 to 1.2 million cases of cutaneous leishmaniasis (CL) are reported each year. The most serious form is VL, which is 90% fatal if left untreated. Treated patients of VL sometimes develop a condition known as post-kala-azar dermal leishmaniasis (PKDL), which presents as dermal lesions that can harbour parasites for years and can act as a reservoir of VL. FIND has been scaling up the fight against leishmaniasis (VL in particular) and is addressing critical diagnostic gaps for the disease by: reducing the burden of leishmaniasis through improved and innovative diagnostic solutions improving detection and understanding of the role of asymptomatic infections and cases of PKDL in regions targeted for elimination. FIND and partners are developing tests for early and accurate diagnosis of leishmaniasis, detection of infection in asymptomatic patients and monitoring treatment. These include tests to detect parasite antigens in the urine of VL patients (antigen detection test) and to detect parasite DNA in various biological samples (molecular detection test). The clinical signs of VL are not specific enough for accurate diagnosis of the disease, as other infections have similar clinical manifestations. Patients with suggestive clinical signs are usually tested serologically, followed by confirmation of the presence of parasites through microscopic examination of bone marrow or splenic aspirates. Due to the complexity associated with sampling, treatment of symptomatic patients is sometimes based solely on positive serological tests. Detection of parasite components such as antigens or DNA would be a better indicator of infection than detecting host antibodies, which remain in the blood for long periods after curative treatment. Most VL patients excrete Leishmania antigens in their urine, but current tests for detecting them are difficult to implement. An easy-to-use test is vital for monitoring treatment. FIND and Kalon Biological have developed a prototype ELISA assay that detects parasite antigens in the urine of VL patients without the need for boiling samples. Promising results were obtained from test samples collected in Bangladesh and East Africa in collaboration with Drugs for Neglected Diseases initiative (DNDi), International Centre for Diarrheal Disease Research, Bangladesh (icddr,b) and Kenya Medical Research Institute (KEMRI). The ELISA assay is being used to test urine samples obtained from patients before, during and after treatment in a study carried out by DNDi in Sudan. In addition, the feasibility of using the ELISA reagents to develop a rapid test is being explored in partnership with Standard Diagnostics, Inc. (SD). FIND is also working with the Royal Tropical Institute (KIT) and the Infectious Disease Research Institute (IDRI) to validate the performance of the ELISA assay using stored samples. Prototype rapid diagnostic tests for VL are being evaluated in clinical trials in Kenya, Sudan and Bangladesh. FIND is committed to establishing strong partnerships to fight leishmaniasis with ministries of health and national programmes in endemic countries, NGOs and Detection of Leishmania DNA in body fluids of patients would be a significant improvement to parasitological examination. In 2011, FIND initiated a partnership with Eiken Chemical Co. Ltd. to develop a test for detecting Leishmania DNA using the loopmediated isothermal amplification (LAMP) technology. LAMP detects pathogen DNA with very high sensitivity and specificity. The reagents for LAMP are dried on the inside of the cap of the reaction tube and, unlike most other molecular tests, target DNA is amplified at a constant temperature. The results are read visually using LED light, meaning the test can be performed with much less laboratory equipment than other DNA detection tests and by technicians with limited training in molecular biology. Development of the LAMP test is being undertaken in collaboration with KIT, the Sanger Institute, TiPharma and Eiken. Eiken has developed prototype LAMP tests using a combination of two sets of primers. One primer set amplifies all species of Leishmania, while the other only amplifies species belonging to the L. donovani complex (which causes VL). The prototype LAMP assay has been evaluated at KIT using purified parasite DNA, and subsequently on a number of clinical samples, including ulcer swabs from CL patients in Colombia, blood from VL patients in Sudan, Ethiopia and endemic controls. Clinical trials to determine the performance of the LAMP kit are being initiated in Kenya, Sudan and Bangladesh. The feasibility of using LAMP to monitor treatment and to identify asymptomatic individuals will also be determined. the WHO. FIND will also work with groups that are discovering novel biomarkers and support validation of reagents that show promise for use in a sensitive test. Leishmaniasis: FIND 2015 – 2020 Priorities and Interventions Development / Policy priorities for new tools: Point-of-care test for diagnosis of VL in eastern Africa that will also diagnose VL in immunocompromised patients (antigen detection) Test of cure for VL and PKDL (antigen detection and/or molecular) Enabling interventions: Facilitate access to specimens for product development Support operational research to improve understanding and management of asymptomatic carriers Campus Biotech Chemin des Mines 9 1202 - Geneva Switzerland T: +41 (0)22 710 05 90 - F: +41 (0)22 710 05 99 www.finddx.org