Listed Disease

Contagious agalactia

Contagious agalactia is a serious disease syndrome of sheep and goats that is characterised by mastitis, arthritis, keratoconjunctivitis and, occasionally, abortion. Mycoplasma agalactiae (Ma) is the main cause of the disease in sheep and goats, but M. capricolum subsp. capricolum (Mcc), M. mycoides subsp. capri (Mmc) and M. putrefaciens (Mp) produce a clinically similar disease, more often in goats, which may be accompanied by pneumonia. The consensus of the working group on contagious agalactia of the EC COST (European Cooperation in the field of on Scientific and Technical Research) Action 826 on ruminant mycoplasmoses was that all four mycoplasmas should be considered as causal agents of contagious agalactia (European Commission, Directorate-General for Research and Innovation, Santini, F., Leori, G., Scanziani, E., COST 826 : Agriculture and biotechnology: Mycoplasmas of ruminants: Pathogenicity, diagnostics, epidemiology and molecular genetics, Publications Office, 1998.   Clinically, the disease caused by Ma is recognised by elevated temperature, inappetence and alteration in the consistency of the milk in lactating ewes with decline and subsequent failure of milk production, often within 2–3 days, as a result of interstitial mastitis. Arthritis, pleurisy, pneumonia, mastitis and keratoconjunctivitis may all result from infection with Mmc. Commercial vaccines for Ma, inactivated with formalin, are widely used, but are not considered to be very efficacious. Live vaccines for Ma have been reported to be more protective than inactivated vaccines. A commercial vaccine containing Ma, Mmc and Mcc is available. No vaccines exist for Mp as the disease it causes is not considered to be sufficiently serious or widespread. In 2015 the first human isolate of Mcc was reported from a man with septicaemia. There are no human health implications because the disease is not zoonotic.