Outbreak of human malaria caused by Plasmodium simium in the Atlantic Forest in Rio de Janeiro: a molecular epidemiological investigation

A molecular epidemiological investigation reveals that an outbreak of malaria in Rio de Janeiro's Atlantic Forest, previously attributed to Plasmodium vivax, is actually caused by Plasmodium simium, a parasite typically found in non-human primates. This discovery challenges the long-standing belief that P. simium does not infect humans and suggests it may have been misdiagnosed as P. vivax due to limited molecular typing techniques. The study analyzed 33 cases from 2015-2016, confirming zoonotic transmission through mitochondrial DNA sequencing. This finding underscores the need for thorough screening of local primates and mosquitoes to assess the public health implications and potential threat to malaria elimination efforts in Brazil.

Brasil, P., Zalis, M. G., de Pina-Costa, A., Siqueira, A. M., Júnior, C. B., Silva, S., Areas, A. L. L., Pelajo-Machado, M., de Alvarenga, D. A. M., da Silva Santelli, A. C. F., Albuquerque, H. G., Cravo, P., Santos de Abreu, F. V., Peterka, C. L., Zanini, G. M., Suárez Mutis, M. C., Pissinatti, A., Lourenço-de-Oliveira, R., de Brito, C. F. A., et al. (2017). Outbreak of human malaria caused by Plasmodium simium in the Atlantic Forest in Rio de Janeiro: a molecular epidemiological investigation. The Lancet Global Health, 5(10), e1038–e1046. https://doi.org/10.1016/s2214-109x(17)30333-9