Streptococcus equi subspecies zooepidemicus – a case report of sudden death in a German sow farm

A farm in North-West Germany experienced a high morbidity and mortality in their sow herd. Sows showed fever, lethargy, oedema, mucosal discharge and dyspnoea. Necropsy revealed a severe fibrinous and purulent polyserositis. Haematological and histological examinations confirmed septicaemia. Streptococcus equi subspecies zooepidemicus was isolated in high yields from major organs. Sequence typing of this isolate (21/455) revealed a new sequence type showing a significantly higher proliferation rate in comparison to two other isolates. Other infectious agents (influenza A virus, Porcine Reproductive and Respiratory Syndrome Virus, Porcine Circovirus 2, african swine fever virus, classical swine fever virus, Actinobacillus pleuropneumoniae) were excluded by routine diagnostic examinations. A climate check revealed an insufficient air supply in the area for the gestating sows. This case describes the first disease outbreak in swine due to S. zooepidemicus in Germany.