CEM Confirmed in British Horse

The United Kingdom's Department for the Environment, Food, and Rural Affairs (Defra) announced the detection of a contagious equine metritis (CEM) carrier stallion  in the Frome area of Somerset (in southwest England) on April 30. Officials said the horse is not believed to have been used for breeding purposes in the U.K.

Contagious equine metritis is a non-systemic, contagious venereal disease of horses that poses no risk to humans. It is not prevalent worldwide, and outbreaks are sporadic. Since 1980, there have been no reported cases except in Europe and Japan. The number of reported cases annually is generally in single figures. The usual measures of control are surveillance, monitoring, screening for detection of carrier stallions and mares, and movement controls.

The disease was last confirmed in Great Britain in a stallion and a mare in 2002 and a mare in 2003. The severity of disease caused by the CEM organism, Taylorella equigenitalis, varies. The main external clinical sign in a mare is a mild to heavy discharge from the vulva, resulting from an inflammation of the uterus (endometritis), cervix, and vagina. Occasionally mares will show no clinical signs. Most mares will experience a period of temporary infertility if they have CEM. Abortion is a very rare sequel to infection. The incubation period ranges from two to 12 days, and the period of clinical disease can last up to two weeks. Infected stallions do not exhibit any clinical signs or evidence of infection with the causal organism which is harbored on their external genitalia.

Further details can be found at: http://www.defra.gov.uk/animalh/diseases/notifiable/disease/contagious_equine_metritis.htm or on the Horserace Betting Levy Board's web site at http://www.hblb.org.uk/hblbweb.nsf/homepage.

Defra has imposed restrictions on the premises on which the infected horse is located as well as  and any possible "at-risk" horses under the Infectious Diseases of Horses Order 1987.

The Horserace Betting Levy Board's Code of Practice, which is aimed at preventing and controlling CEM, has also been endorsed by the horse industries in France, Ireland, Germany and Italy. Defra advises those intending to use horses for breeding to follow the guidelines for disease prevention that are contained in the code. The disease is notifiable in the U.K., but there are no European Union rules on controlling CEM. Some countries require disease-free status for CEM for trade purposes. There were 14 UK cases in 1996, two in 1997, two cases in 2002, and one case in 2003. After the last outbreak, the UK had regained disease-free status.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from TheHorse.com. Learn More