Contagious equine metritis: how to spot and report the disease

Contagious equine metritis (CEM) affects horses, donkeys, mules, zebras and other equidae and is passed on through sexual contact. It does not affect humans.

Clinical signs

CEM is a venereal infection of the genital tract of horses triggered by the Taylorella equigenitalis bacteria.

Stallions do not normally show clinical signs of the disease, but can be carriers of it. Infected mares experience discharge from swollen genitals, especially one to six days after mating, and may also be temporary infertile. 

How contagious equine metritis is spread

CEM is spread from horse to horse during mating, but it can also be spread when horses are artificially inseminated.

Vaccination

There is no vaccination available for CEM.

Human health implications

There are no human health implications becuase the disease is not zoonotic.

Disease control

If the disease is confirmed the outbreak will be controlled in line with the contingency plan for exotic notifiable diseases.

Legislation

The main domestic legislation on CEM is the Infectious Diseases of Horses Order 1987.

Biosecurity

The Government's policy on disease control is that prevention is better than cure. This approach works by reducing the chances of a disease entering the animal population, and if it does then it can be quickly spotted and dealt with through the preventative measures.

Biosecurity is about being aware of the ways disease can spread, and taking every practical measure to minimise the risk of disease spreading.