title: Dynamical malaria models reveal how immunity buffers effect of climate variability.
abstract: Assessing the influence of climate on the incidence of Plasmodium falciparum malaria worldwide and how it might impact local malaria dynamics is complex and extrapolation to other settings or future times is controversial. This is especially true in the light of the particularities of the short- and long-term immune responses to infection. In sites of epidemic malaria transmission, it is widely accepted that climate plays an important role in driving malaria outbreaks. However, little is known about the role of climate in endemic settings where clinical immunity develops early in life. To disentangle these differences among high- and low-transmission settings we applied a dynamical model to two unique adjacent cohorts of mesoendemic seasonal and holoendemic perennial malaria transmission in Senegal followed for two decades, recording daily P. falciparum cases. As both cohorts are subject to similar meteorological conditions, we were able to analyze the relevance of different immunological mechanisms compared with climatic forcing in malaria transmission. Transmission was first modeled by using similarly unique datasets of entomological inoculation rate. A stochastic nonlinear human-mosquito model that includes rainfall and temperature covariates, drug treatment periods, and population variability is capable of simulating the complete dynamics of reported malaria cases for both villages. We found that under moderate transmission intensity climate is crucial; however, under high endemicity the development of clinical immunity buffers any effect of climate. Our models open the possibility of forecasting malaria from climate in endemic regions but only after accounting for the interaction between climate and immunity.
authors.affiliation: Institut Català de Ciències del Clima, Climate Dynamics and Impacts Unit, 08005 Barcelona, Catalonia, Spain; Centro Atómico Bariloche, Consejo Nacional Investigaciones Científicas y Técnicas, Grupo de Física Estadística e Interdisciplinaria, 8400 S. C. de Bariloche, Rio Negro, Argentina; karinalaneri@gmail.com.
authors.forename: Karina
authors.initials: K
authors.lastname: Laneri
authors.affiliation: Institut Pasteur, Unité de la Génétique Fonctionnelle des Maladies Infectieuses, Department of Genomes and Genetics, F-75724 Paris cedex 15, France; Centre National de la Recherche Scientifique, Unité de Recherche Associée 3012, F-75015 Paris, France;
authors.forename: Richard E
authors.initials: RE
authors.lastname: Paul
authors.affiliation: Institut Pasteur de Dakar, Unité d'Epidémiologie des Maladies Infectieuses (UR 172), BP 220 Dakar, Senegal;
authors.forename: Adama
authors.initials: A
authors.lastname: Tall
authors.affiliation: Institut Pasteur de Dakar, Unité d'Epidémiologie des Maladies Infectieuses (UR 172), BP 220 Dakar, Senegal;
authors.forename: Joseph
authors.initials: J
authors.lastname: Faye
authors.affiliation: Institut Pasteur de Dakar, Unité d'Epidémiologie des Maladies Infectieuses (UR 172), BP 220 Dakar, Senegal;
authors.forename: Fatoumata
authors.initials: F
authors.lastname: Diene-Sarr
authors.affiliation: Institut de Recherche pour le Développement, Unité de Pathogénie Afro-Tropicale (Unité Mixte de Recherche 198), Département Santé, BP 1386, CP 18524, Dakar, Senegal;
authors.forename: Cheikh
authors.initials: C
authors.lastname: Sokhna
authors.affiliation: Institut de Recherche pour le Développement, Unité de Pathogénie Afro-Tropicale (Unité Mixte de Recherche 198), Département Santé, BP 1386, CP 18524, Dakar, Senegal;
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Trape
authors.affiliation: Institut Català de Ciències del Clima, Climate Dynamics and Impacts Unit, 08005 Barcelona, Catalonia, Spain; Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Catalonia, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Rodó
mesh_terms: D002980:Climate; D006801:Humans; D015994:Incidence; D016778:Malaria, Falciparum / Q000453:epidemiology* / Q000635:transmission; D008962:Models, Theoretical
keywords: Plasmodium falciparum malaria; climate; endemicity; immunity; vector-borne diseases