Reemerging of natural infection by Trypanosoma evansi in horses in Arari, Marajo Island, Brazil/Reemergencia da infeccao natural por Trypanosoma evansi em cavalos, na regiao do Arari, Ilha do Marajo, Brazil

• Published in: Ciência rural 2016-12, Vol.46 (12), p.2170
• Main Authors: da Silva, Josileide Araujo, Domiciano, Tarcisio Oliveira, Montao, Daniele Pina, Sousa, Paulo Geovani Silva, Ramos, Leandro Lopes, Paredes, Laura Jamille Argolo, Monteiro, Silvia Gonzalez, Rivero, Gabriela Riet Correa, Scofield, Alessandra, Bezerra, Jr., Pedro, Bezerra, Isis Abel, Cerqueira, Valiria Duarte
• Format: Article
• Language: Spanish
• ISSN: 0103-8478
• DOI: 10.1590/0103-8478cr20160047

Two outbreaks of trypanosomiasis by Trypanosoma evansi in horses in the municipality of Chaves, Marajo Island, Para State, Brazil are reported. The first outbreak occurred in April 20H in a farm with 147 horses; of these, 47 (31.97%) got sick, and 40 (27.21%) died. The second outbreak occurred in May 2012 and involved nine properties. Of a total of 679 horses, 209 (30.07%) got sick, and 183 (26.97%) died. The main clinical signs observed in these horses were weight loss, abdominal edema, toe dragging, and pelvic muscle atrophy. Necropsy was performed in two horses, one from each outbreak. Macroscopic alterations were not seen in the horse from the first outbreak; however, the horse from the second outbreak exhibited emaciation, pallor and icterus, as well as enlarged spleen with prominent white pulp at cut surface. Histopathology of the central nervous system of both animals revealed mild to severe, diffuse lymphoplasmacytic encephalitis, with presence of Mott cells. Immunohistochemistry for T evansi revealed structures similar to intralesional trypomastigote forms. Between November and December of 2013, an epidemiological survey was carried out in the municipalities of Cachoeira do Arari, Santa Cruz do Arari, Salvaterra, Soure, and Chaves. Only Santa Cruz do Arari and Chaves had reported cases of the disease. Blood samples were collected from 243 horses for detection of T evansi DNA by polymerase chain reaction (PCR) and 20 were positive. Key words: equids, trypanosomiasis, Para, Marajo Island. Sao relatados dois surtos de tripanossomiase por Trypanosoma evansi, em cavalos no municipio de Chaves, Ilha do Marajo, Para, Brasil. O primeiro surto ocorreu em abril de 2011 em uma fazenda com 147 cavalos, em que 47 (31,97%) adoeceram e 40 (27,21%) morreram. O segundo ocorreu em maio de 2012 e envolveu nove propriedades. De um total de 619 cavalos, 209 (30,07%) adoeceram e 183 (26,97%) morreram. Os principais sinais clinicos observados foram perda de peso, edema abdominal, emboletamento dos membros e atrofia da musculatura da regiao pelvica e membros posteriores. A necropsia foi realizada em dois cavalos, um de cada surto. O equino do primeiro surto nao apresentou lesoes macroscopicas, enquanto o segundo, do segundo surto, apresentava emagrecimento, palidez e ictericia, aumento do baco com protrusao da polpa branca ao corte. O sistema nervoso central de ambos os animais revelou uma leve a severa encefalite linfoplasmocitaria, difusa, com presenca de celulas de Mo