Zoonotic and Anthroponotic Plasmodium spp. Circulation between Wild Primates and Indigenous Community, Peruvian Amazon, 2007-2020.

Malaria transmission at the human-wildlife interface remains poorly characterized in the Amazon. We conducted a molecular survey of Plasmodium spp. in an Indigenous community (n = 141) and sympatric nonhuman primates (NHPs) (n = 341; 10 species) in the Peruvian Amazon during 2007-2020. By using nested or quantitative PCR (targeting cytb, cox3, and 18S rRNA genes) and sequencing, we estimated prevalence, parasite load, and genetic similarity. We detected Plasmodium in 43.3% of humans and 51.9% of NHPs. P. vivax/simium predominated in humans (42.1%), whereas P. brasilianum/malariae predominated in NHPs (24.6%). P. falciparum was rare in both hosts. Children <8 years of age showed higher parasite load than older persons. Bayesian phylogenies revealed >99.9% identity among human and NHP lineages, supporting shared Plasmodium lineages. NHP lineages showed low interannual variation. One third of human infections were asymptomatic. Our findings reveal hidden reservoirs and support integrating wildlife surveillance into Amazon malaria elimination strategies.