Contagious Equine Metritis - CEM

This Code of Practice covers disease caused by three species of bacteria:

  • Taylorella equigenitalis (the contagious equine metritis organism - CEMO)
    Contagious equine metritis (CEM) caused by this organism was first diagnosed in 1977 in Newmarket. The cause, T.equigenitalis, was until then unknown.  Following the development and application of this Code of Practice, CEM was eradicated in the UK and has occurred only sporadically since.  This organism occurs widely in the non-Thoroughbred population, and to a limited extent in Thoroughbreds, in mainland Europe. 
  • Klebsiella pneumoniae (K. pneumoniae)
    This organism is found in the environment and can cause infections in a variety of animal species, and in humans. There are many capsule types of K. pneumoniae, most of which do not cause venereal disease. However, types 1, 2 and 5 may be sexually transmitted in horses. Therefore, when K. pneumoniae is identified from breeding stock, tests to determine the capsule type(s) present must be undertaken.
  • Pseudomonas aeruginosa (P. aeruginosa)
    This organism in also found in the environment and can cause infections in a variety of animal species and in humans. Not all strains of P. aeruginosa cause equine venereal disease but there is no reliable method to differentiate between the strains. Therefore, all isolates should be considered as potential venereal pathogens.

Both K. pneumoniae and P. aeruginosa occur from time to time within Europe.