First report of an outbreak of ovine septicaemic listeriosis in Saudi Arabia

Although a case of human listeriosis has recently been reported in Saudi Ar abia, the disease has not been reported in animals to date. The authors des cribe an outbreak of septicaemic listeriosis in sheep, which occurred durin g winter. Adult animals and pregnant ewes were principally affected, with a morbidity rate of 7.1% and a mortality rate of 2.4%; no abortions were rec orded during the outbreak. Clinical signs included inappetence, weakness, f ever, respiratory distress, keratoconjunctivitis and compulsive circling. L isteria monocytogenes was isolated in pure culture from affected sheep. Pat hological findings indicated septicaemic listeriosis with encephalitis. Hyg ienic measures and antibiotics were successful in treating the rest of the flock. Aspects of the outbreak and public health implications are discussed .