Visceral leishmaniasis research: operational focus needed
Authors: Richard Reithinger
Journal: The Lancet Global Health (2015)

The UK Department for International Development has launched the first ever large-scale effort, KalaCORE,1UK Department of International DevelopmentAnnual review: tackling visceral leishmaniasis in south Asia and east Africa. Department of International Development, London2014iati.dfid.gov.uk/iati_documents/4584715.docxGoogle Scholar to control visceral leishmaniasis. Funding of up to £26·3 million will be provided to tackle visceral leishmaniasis in south Asia and east Africa, the two endemic regions with more than 85% of the global visceral leishmaniasis cases. Through KalaCORE, more than 250 000 cases are hoped to be treated, averting 55 000 deaths. In east Africa, support will aim to reduce the burden of visceral leishmaniasis, whereas support in south Asia will focus on complementing ongoing national efforts to eliminate visceral leishmaniasis.1UK Department of International DevelopmentAnnual review: tackling visceral leishmaniasis in south Asia and east Africa. Department of International Development, London2014iati.dfid.gov.uk/iati_documents/4584715.docxGoogle Scholar Greg Matlashewski and colleagues2Matlashewski G Arana B Kroeger A et al.Research priorities for elimination of visceral leishmaniasis.Lancet Glob Health. 2014; 2: e683-e684Summary Full Text Full Text PDF Scopus (25) Google Scholar (December, 2014, issue) emphasise research priorities for visceral leishmaniasis elimination, which include the assessment of improved and shorter drug regimens, the role of asymptomatic and post-kala azar dermal leishmaniasis cases in disease epidemiology, and vaccine development. Undoubtedly, these are important research priorities. However, three research areas crucial to the success of operational programmes, such as KalaCORE, are not discussed, and—if omitted—could hamper any substantial progress in the tackling of the visceral leishmaniasis burden worldwide. First, there is no mention of insecticide and drug resistance, both of which are particularly prevalent in the Indian subcontinent.3Croft SL Sundar S Fairlamb AH Drug resistance in leishmaniasis.Clin Microbiol Rev. 2006; 19: 111-126Crossref PubMed Scopus (1300) Google Scholar, 4Dinesh DS Das ML Picado A et al.Insecticide susceptibility of Phlebotomus argentipes in visceral leishmaniasis endemic districts in India and Nepal.PLoS Negl Trop Dis. 2010; 4: e859Crossref PubMed Scopus (67) Google Scholar How resistance affects the effect of vector control efforts (ie, insecticide-treated bednets and indoor residual spraying of households with insecticide) and case management in an operational context, and how programme failure relates to actual resistance versus poor programme implementation (eg, suboptimum spraying of households with insecticide or non-compliance of patients to anti-leishmania drugs) are equally important questions. Second, aspects relevant to the surveillance of visceral leishmaniasis are not discussed. Research in this area could—similar to other neglected tropical diseases5Sturrock HJ Picon D Sabasio A et al.Integrated mapping of neglected tropical diseases: epidemiological findings and control implications for northern Bahr-el-Ghazal State, Southern Sudan.PLoS Negl Trop Dis. 2009; 3: e537Crossref PubMed Scopus (41) Google Scholar—include the development of a standardised approach for mapping and surveillance of visceral leishmaniasis to improve our understanding of its distribution and endemicity, which presently relies on passively reported in-country case notifications.6Pigott DM Bhatt S Golding N et al.Global distribution maps of the leishmaniases.eLife. 2014; : 3Google Scholar Moreover, visceral leishmaniasis is not necessarily a notifiable disease; approaches should be developed and piloted to ensure that all cases of visceral leishmaniasis are detected and reported. Rigorous reporting will become particularly important if transmission intensity decreases (eg, in Nepal and Bangladesh) and elimination becomes a real possibility. Finally, operational research should assess how diagnostic testing could be operationalised in health facilities that already provide services for malaria or tuberculosis; areas sympatric for visceral leishmaniasis and malaria could be prioritised for vector control. Research that addresses the above-mentioned operational questions and challenges would ensure that programmes such as KalaCORE will yield maximum effect, especially as these programmes remain few and far between. I declare no competing interests. Research priorities for elimination of visceral leishmaniasisNow is a good time to reconsider research priorities as 2015 approaches, the target date originally set for elimination of visceral leishmaniasis. Visceral leishmaniasis is one of the most deadly parasitic diseases and disproportionately affects the poorest and most vulnerable populations. An estimated 200 000–400 000 people contract visceral leishmaniasis every year in developing countries. Spread by sandflies, visceral leishmaniasis can be fought with existing interventions, including treatment and vector control, but, similarly to every other human parasitic disease, no effective vaccine exists. Full-Text PDF Open Access