Climate Change, Vector-Borne Diseases, and Migration
This chapter offers a critical overview of the recent literature on climate change, vector-borne diseases, and migration in the context of developing countries. Increasing global temperature combined with extreme weather events is creating highly favorable conditions for the persistence, faster geographic spread, and re-emergence of vector-borne diseases being targeted for elimination, such as malaria, dengue, chikungunya, yellow fever, leishmaniasis, lymphatic filariasis, Chagas disease, schistosomiasis, onchocerciasis, Lyme disease, or Zika virus, because they are climate-sensitive diseases by modifying conditions that affect vectors development. At the same time, climate change intensifies poverty and inequality, which can induce both within and across borders migration playing a role in parasite dispersal and reversing gains of prevention activities and control programs made over decades. The channels through which migration affects vector-borne diseases are poorly understood. They can be negative or positive depending on who migrates, to where and on how migration influences health outcomes during all phases of the migration journey (at the origin, during transit, at the arrival, and return). While the literature has mainly focused on migration as a threat (transmission mechanism), a recent strand gives also support to the development impact of migration and the transfers of health information, preventive practices, and behavioral norms between host and home communities (diffusion mechanism).