Visceral leishmaniasis (VL), also known as Kala Azar, is a parasitic disease caused by species of the Leishmania genus. While other forms of leishmaniasis exist, VL is recognised as the most severe manifestation. Symptomatic VL infection is often associated with prolonged fever, enlargement of the spleen, fatigue, weakness, and weight loss. Without appropriate treatment, patients will usually die.
Over 90% of VL cases worldwide occur in only five countries, of which India is one. In India, the species causing VL, Leishmania donovani, is transmitted by the sandfly Phlebotomus argentipes. The disease primarily affects people living in low socio-economic conditions, particularly in rural villages. This is likely because impoverished individuals are likely to have inadequate access to high-quality housing and nutrition, and suffer from additional morbidities. Proximity to infected individuals has also been identified as a risk factor for contracting Kala Azar.
VL has been targeted for elimination as a public health problem, defined as less than one case per 10,000 people at block level, in the Indian subcontinent by 2017. Whilst the number of new cases has falled in recent years and some areas of India have achieved this goal already, others have not, and yet others have experienced a resurgence of disease incidence. Approximately 58 districts in the country's north-eastern states, particularly Bihar, Uttar Pradesh, Jharkhand and West Bengal, continue to regularly report cases.
Control of VL in India to date has focussed on intensive disease management, including improving access to diagnosis and treatment, and vector control through indoor residual spraying (IRS). In order to achieve and progress beyond the elimination goal, unanswered questions about P. argentipes behaviour and L. donovani transmission need to be answered though. Additionally, the VL surveillance system will need to be optimised, and the health system strengthened to ensure case numbers do not resurge.
Further information on Kala Azar in India can be found in this factsheet.
The Setting the Post-Elimination Agenda for Kala Azar in India (SPEAK India) consortium provides a shared, accessible platform for VL researchers, implementers and stakeholders working in the Indian subcontinent to exchange experiences, synchronise activities, and identify synergies in their work to ensure optimal use of resources. In doing so, SPEAK India aims to identify and define the key questions, knowledge gaps and data needs that should be addressed for the VL elimination goal to be achieved, and sustained into the future.
Funded by the Bill & Melinda Gates Foundation and facilitated by the London School of Hygiene and Tropical Medicine, SPEAK India is led by Professor Soumya Swaminathan, Director General of the Indian Council of Medical Research (ICMR), and has strong support from India's National Vector Borne Disease Control Programme, Rajendra Memorial Research Institute for Medical Sciences (RMRIMS), Banaras Hindu University, Institute of Public Health Bengaluru (IPH), and the Drugs for Neglected Diseases initiative.
Since its establishment in 2016, SPEAK India has worked to identify stakeholders involved in VL elimination activities in the Indian subcontinent, and bring them together to design a research agenda for VL. Three cross-cutting themes, supported by mathematical modelling, have been identified to guide the development and implementation of research projects:
To date, SPEAK India has hosted two residential meetings in India. The first, held in Delhi in November 2016, sought to offer an overview of the current status of VL in India and challenges related to elimination, and provide a space for consortium members to formulate research questions to be answered through multidisciplinary groups. The second took place in Varanasi, and served as a forum for members to present research proposals to address these questions, receive feedback, and identify areas of synergy with other consortium members' proposals. Further information on these meetings and the presentations given can be found on the News and Outputs pages.