Spirochaetes transmitted by ticks are microorganisms of worldwide distribution, which infect wild, domestic animals and human beings. A total of 300 equine sera from four municipalities: Ananideua (58), Belém (61), Castanhal (131), and Santa Izabel do Pará (50), were evaluated for Borrelia burgdorferi by an Elisa test. There were no significant differences (P<0.05) among municipalities, breed, sex or husbandry. A total of 80 (26.7%) horses were B. burgdorferi positive with titles of 1:800, 72 (90%) horses, 1:1.600, 6 (7.5%) horses, and 1:3.200, 2 (2.5%) horses. The results were similar to those in the USA, where related frequencies ranged from 7 to 75% in asymptomatic seropositive horses. The presence of anti-B.burgdorferi homologous antibodies in horses from four municipalities in the metropolitan mesorregion of Belém suggests the possibility of occurrence of human cases in the region.
Borrelia burgdorferi; Spirochaetacae; horses; serology