Genomic exploration of the journey of Plasmodium vivax in Latin America.

Plasmodium vivax is the predominant malaria parasite in Latin America. Its colonization history in the region is rich and complex, and is still highly debated, especially about its origin(s). Our study employed cutting-edge population genomic techniques to analyze whole genome variation from 620 P. vivax isolates, including 107 newly sequenced samples from West Africa, Middle East, and Latin America. This sampling represents nearly all potential source populations worldwide currently available. Analyses of the genetic structure, diversity, ancestry, coalescent-based inferences, including demographic scenario testing using Approximate Bayesian Computation, have revealed a more complex evolutionary history than previously envisioned. Indeed, our analyses suggest that the current American P. vivax populations predominantly stemmed from a now-extinct European lineage, with the potential contribution also from unsampled populations, most likely of West African origin. We also found evidence that P. vivax arrived in Latin America in multiple waves, initially during early European contact and later through post-colonial human migration waves in the late 19^th-century. This study provides a fresh perspective on P. vivax's intricate evolutionary journey and brings insights into the possible contribution of West African P. vivax populations to the colonization history of Latin America. Author summary: Our study investigates the origins and spread of Plasmodium vivax in Latin America, the primary malaria parasite in this region. By analyzing genetic data from 620 P. vivax samples worldwide, including new samples from West Africa, the Middle East, and Latin America, we were able to reconstruct the evolutionary history of the parasite in this region. Our findings indicate that the current P. vivax strains in Latin America mainly descended from a now-extinct European lineage. Additionally, we found evidence suggesting that several migration waves following human migrations waves may have contributed to the parasite diversity, with possible contributions from West African populations during the transatlantic slave trade (16^th to 19^th century) and further input from Europe during post-colonial human migrations in the late 19^th century. This study offers a fresh perspective on how historical human migrations have shaped the genetic landscape of P. vivax in Latin America. These insights are valuable for understanding the parasite evolution and may help inform strategies for malaria control and prevention in the future. [ABSTRACT FROM AUTHOR]