Instructions on how to make an Outbreak of American Cutaneous Leishmaniasis

Abstract

Outbreaks of American Cutaneous Leishmaniasis (ACL) are triggered by the confluence of multidimensional biological, climate, and social factors: the eco-epidemiological momentum. Despite the diversity of epidemiological scenarios, there are common “Ingredients for the recipe” to make an ACL outbreak. To describe the “Where”, “When”, and “Why” of this momentum could contribute to the understanding of the causes of epidemics, preventing their occurrence, and to define better strategies to control them. Typically, due to sylvatic-rural transmission, most urban ACL are still related in time and space to peripheral city deforestations, riparian forest, and green patches within the cities. Therefore, the “Where” of the ACL outbreaks could be characterized in the space as an edge effect, and afterwards the “When” of this edge could be categorized as an ephemeral, transient or permanent. The “Why” question is far more complex, as it includes the exposure of humans to vector due to anthropic activities in each edge scenario. The evidence for ACL outbreak control strategies: barricading the edge by chemical and physical barriers, environmental management, and individual prevention, were reviewed. Answers to questions regarding these “Where”, “When”, “Why”, and “How to control” guided the content of the questions to be asked in the new focus of ACL transmission, not only to mitigate current transmission and prevent future outbreaks, but also to highlight the biological factors that might contribute to the possibility of an epidemic, and those conditions that modulate its actual probability, the climate and the social determination of risk.