Detecção de anticorpos anti-Toxoplasma gondii em marsupiais e roedores silvestres da Mata Atlântica do Estado de Pernambuco, Nordeste do Brasil

Abstract

In order to improve the environmental health of ecosystems and the health of human and animal populations, studies about possible pathogens transmitted by wild rodents and marsupials are essential to pursue new strategies to prevent and control the spread of diseases. The aim of this study was to determine the seroprevalence of antibodies against Toxoplasma gondii in seven species of wild marsupials and seven species of wild rodents captured in seven areas of the Atlantic Forest in the State of Pernambuco, in the Northeast of Brazil. Between December 2007 and March 2009, we captured a total of 397 animals: 223 marsupials and 174 rodents, male and females of different age groups. The serum blood samples were tested using the Modified Agglutination Test (MAT) containing tachyzoites that were inactivated in formalin and 2-mercaptoetanol. The cutoff was set at 1:25. Antibodies against T. gondii were determined in 15/223 (6.7%) of marsupial blood samples 10/174 (5.7%) of rodent blood samples. Antibody titles were: 25 in six marsupials and six rodents, 50 in seven marsupials and three rodents; and 500 in two marsupials and one rodent. Serum of the following species of marsupials presented positive results: 11.7% (9/77) Didelphis albiventris, 10.0% (1/10) Monodelphis domestica, 9.5% (2/21) Metachirus nudicaudatus,3.8% (1/26) Didelphis aurita, 2.3% (1/43) Marmosa murina and 2.3% (1/43) Marmosa demerarae. Serum samples of the following species of rodents presented positive results 33.3% (3/9) Rattus rattus, 8.3% (2/24) Nectomys rattus, 5.5% (2/36) Akodon cursor and 3.0% (3/100) of Thrichomys laurentius. Regarding the site of capture, positive animals were captured in 75.0% (6/8) of sites. The results of this study are the first record of anti-T. gondii antibodies in marsupials and rodents in Northeastern Brazil. The detection of antibodies against T. gondii in the serum of marsupials and rodents in the Atlantic Forest of Pernambuco suggests that the agent has spread in the biome and indicates previous infection of animals that had positive serum test results. The results of this study suggest that small mammals can play an important role in the epidemiological chain of T. gondii in the Atlantic Forest of Pernambuco, in the Northeast of Brazil.