Pesquisa de DNA de Plasmodium em amostras de fígado de símios mortos

Abstract

Malaria is a major global public health problem. Although notorious for the distribution of cases in the Amazon region, it is also known to be endemic in the dense forests of southeastern Brazil. The infection is called residual malaria from Atlantic Forest systems in these areas. In the region as a whole, the presence of simian malaria is also proven. Given the possibility of the disease being a zoonosis in these regions, it is necessary to understand its behavior in non-human primate populations, in order to predict the zoonotic risk. In addition, the transfer of Plasmodium between apes and humans deserves to be investigated. The objective of this work was to identify the presence of Plasmodium DNA in liver samples from apes killed by yellow fever in the municipalities of the mountainous region of Espírito Santo. The last epidemic of yellow fever recorded in Espírito Santo resulted in the death of many apes. This enabled the collection of liver fragments from the bodies of non-human primates that could be located. DNA of Plasmodium spp. was extracted from these samples and amplified by RT-qPCR. Seventy liver fragments of apes from the municipalities of Santa Maria de Jetibá, Domingos Martins, Santa Teresa, Marechal Floriano, Vila Velha, Sooretama, São Mateus, Afonso Cláudio and Itaguaçu, in the state of Espírito Santo, and from Caratinga, in Minas Gerais, were analyzed. The commercial kit of the company Qiagen (DNeasy Blood and Tissue Kit) was used for the extraction of DNA, according to the manufacturer's protocol (Spin-Column Protocol). PCR amplification was performed in real time quantitative(RT-qPCR) in the Taqman system. The experiments were conducted at the Institute of Tropical Medicine, at the University of São Paulo (IMT-USP), in technical collaboration with the team at the Protozoology Laboratory. Of the 70 liver samples analyzed, a frequency of 15 positive samples (21.43%) was found: seven for Plasmodium falciparum, four for Plasmodium malariae, one for Plasmodium vivax, one for Plasmodium vivax and P. falciparum concomitantly and two for the Plasmodium genus. Of the positive samples, five were collected from apes found in Domingos Martins, four in Santa Maria de Jetibá, one in Santa Teresa, one in Marechal Floriano, one in Caratinga/MG and three in unknown locations. Regarding the species of apes whose fragments were positive, all were of the species Alouatta guariba. Given the importance of apes as hosts for zoonotic diseases and their role as a reservoir for several emerging infectious diseases, the evidence of the presence of Plasmodium spp. Infecting these apes can indicate the possible role of non-human primate populations in maintaining malaria transmission in regions close to areas of the Atlantic Forest