The comparative epidemiology of P. falciparum and P. vivax transmission in Papua New Guinea, Thailand and Brazil
Iniciativas: Eliminación de la malaria
This project aims to contribute towards improved control and eventual elimination of malaria in the Asia-Pacific and Americas through gaining an in-depth understanding of transmission patterns of P. falciparum and P. vivax".
The main goal is to determine the dynamics of malaria transmission stages in host and vector in 3 non-African settingsand determine bottlenecks and their impact transmission and parasite population diversity.
While we have an increasing knowledge of the biology of P. falciparum (Pf) gametocytes and at least a basic understanding of epidemiology of Pf transmission in sub-Saharan Africa, very little is known both about the epidemiology of malaria transmission in non-African setting in general and for P. vivax (Pv) in particular. Some of the most fundamental questions underlying the spatial and temporal patterns of gametocyte carriage, infectivity and recombination in the mosquito remain unknown. A thorough reassessment of our concept of the infectious reservoir through coordinated sets of carefully planned population-based studies is essential if we are to optimize the existing or develop new control tools to eventually achieve malaria elimination in the American and the Asia-Pacific.
By combining epidemiological study design and membrane feeding protocols that are standardized between sites and harmonized with ongoing transmission / infectivity studies in Africa with state-of-the-art molecular assays for detection and genotyping of Pf and Pv gametocytes, this project aim to provide an in-depth understand in transmission patterns in a holoendemic area of PNG, a low-to-moderate transmission area with equal Pf and Pv transmission in Western Thailand and a predominantly low P. vivaxtransmission area in the Brazilian Amazon.
These studies will give insight into differences in time course of gametocytaemia and its association with asexual parasite density and febrile symptoms as well as investigating the effect of supra-infections (by same or different species) on Pf vs. Pv gametocyte production. In parallel with these epidemiological studies, membrane-feeding experiments (using established colonies of local Anopheline vectors) will be conducted. These studies will determine the relationship between gametocyte density and mosquito infectivity (all 3 sites) as well as to identify transmission bottlenecks in human and vector hosts and their effect on Pf and Pv transmission potential (PNG & Thailand). Results from all theses studies will be shared with local and regional stakeholder involved in malaria control and development of novel tools.