Reemergence of Dourine in Italy: Clinical Cases in Some Positive Horses

In 2011, Trypanosoma equiperdum reemerged in Italy, almost 10 years after its last appearance. A total of eight infected horses have been observed to date. Six horses were affected by natural outbreaks of the disease, whereas two were infected experimentally. The aim of this study was to offer a recent perspective on clinical cases of dourine in Europe. Investigation of the clinical aspects confirmed the three stages reported in the literature: stage 1 (genital lesions), stage 2 (cutaneous signs), and stage 3 (nervous signs). The most common signs in the horses under study were notable weight loss, edematous skin eruptions and oedemas of the abdomen, mammary glands and hind legs. Three animals presented neurological signs (lip ptosis of lower lip and ataxia). Infections were paucisymptomatic or asymptomatic in some animals. Hyperthermia was not reported in infected animals and considerable anemia was observed. High antibody titers did not always correspond to clinical signs. Positive polymerase chain reaction test results of blood or tissue (skin, eye swab) often correspond to an advanced stage of the disease. Dourine is a variable disease; owing to its low prevalence and chronic manifestation, it can be difficult to make a quick diagnosis when facing a Dourine-positive horse.