Research Article Comparison of three methods for diagnosis of Trypanosoma (Duttonella) vivax in cattle

Abstract

Detection of Trypanosoma vivax in cattle is based on parasitological, serological and molecular methods. The aim of this study was to compare three different methods for detecting T. vivax during an outbreak of trypanosomiasis in southeast Brazil. Blood samples were collected from seventy-two animals to perform microhematocrit centrifugation technique (MHCT), indirect fluorescent antibody (IFAT), and polymerase chain reaction (PCR). A total of 84.72% (61/72) of the samples yielded a positive result in at least one test. The PCR test yielded the highest number of positives [73.6% (53/72)], followed by the IFAT [61.1% (44/72)] and MHCT [29.0% (21/72)]. Agreement among the three methods, as expressed by the kappa value, was poor. PCR proved to be the most sensitive of the three methods by demonstrating the highest positivity rate, even in the presence of low parasite levels. This work presents the first study comparing three different detection tests, to T. vivax, analyzing a relatively large-scale number of samples.