How does Visceral Leishmaniasis differ betweenBrazil and India, and can the same strategies used in India be implemented in Brazil to reduce disease burden?

Visceral leishmaniasis (VL) is a type of leishmaniasis and a neglected tropical disease. It is most prominent in Brazil and India, caused by parasites L. infantum and L. donovani (respectively); these are spread by various species of female sandflies. Case numbers in India were high until the National Kala-Azar Elimination Programme (NKAEP) was implemented. Over time, it became a strong eradication programme, causing a sharp decline in cases. However, Brazil has not achieved a significant case reduction, despite having an NKAEP equivalent: the Visceral Leishmaniasis Surveillance and Control Programme (VLSCP). Although the VLSCP targets certain factors, it is less efficient than the NKAEP. This review aims to analyse all major factors for this difference and evaluate whether Brazil can use similar strategies as India to reduce disease burden.To investigate this, the similarities and differences between parasites, vectors, reservoirs, socioeconomics, geography, poverty, and treatment strategies were compared. In Brazil, parasite genetics affect the efficacy of drug treatments; reservoirs, hosts, and sandfly behaviours impact the effectiveness of strategies implemented by the VLSCP; limited government funding towards the science sector affected the development of better therapies. Whilst Indian VL was less complex, its higher prevalence may have facilitated reduction efforts. The context in Brazil is different; therefore, using the same strategies as India is not proving as effective. It must look at solving extra problems such as multiple hosts, a more feasible way to handle the problems reservoirs cause in the disease transmission, and looking at developing more effective treatments.