Climate drivers of malaria at its southern fringe in the Americas

• Autores: Laneri, Karina Fabiana; Cabella, Brenno; Prado, Paulo Inácio; Coutinho, Renato Mendes; Kraenkel, Roberto André
• Año de publicación: 2019
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: malaria; climate; Argentina
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

In this work we analyze potential environmental drivers of malaria cases in Northwestern Argentina. We inspect causal links between malaria and climatic variables by means of the convergent cross mapping technique, which provides a causality criterion from the theory of dynamic systems. Analysis is based on 12 years of weekly malaria P. vivax cases in Tartagal, Salta, Argentina—at the southern fringe of malaria incidence in the Americas—together with humidity and temperature time-series spanning the same period. Our results show that there are causal links between malaria cases and both maximum temperature, with a delay of five weeks, and minimum temperature, with delays of zero and twenty two weeks. Humidity is also a driver of malaria cases, with thirteen weeks delay between cause and effect. Furthermore we also determined the sign and strength of the effects. Temperature has always a positive non-linear effect on cases, with maximum temperature effects more pronounced above 25C and minimum above 17C, while effects of humidity are more intricate: maximum humidity above 85% has a negative effect, whereas minimum humidity has a positive effect on cases. These results might be signaling processes operating at short (below 5 weeks) and long (over 12 weeks) time delays, corresponding to effects related to parasite cycle and mosquito population dynamics respectively. The non-linearities found for the strength of the effect of temperature on malaria cases make warmer areas more prone to higher increases in the disease incidence. Moreover, our results indicate that an increase of extreme weather events could enhance the risks of malaria spreading and re-emergence beyond the current distribution. Both situations, warmer climate and increase of extreme events, will be remarkably increased by the end of the century in this hot spot of climate change.
Fil: Laneri, Karina Fabiana. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (cab). División Física Estadística; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentina
Fil: Cabella, Brenno. Universidade Estadual Paulista Julio de Mesquita Filho. Faculdade de Engenharia; Brasil
Fil: Prado, Paulo Inácio. Universidade de Sao Paulo; Brasil
Fil: Coutinho, Renato Mendes. Universidad Federal Do Abc; Brasil
Fil: Kraenkel, Roberto André. Universidade Estadual Paulista Julio de Mesquita Filho. Faculdade de Engenharia; Brasil