OTTAWA — An infection known as "strangles" has hit the famous horses of the RCMP and forced the national police force to cancel a series of its signature musical rides in Alberta and Saskatchewan.

The Mounties have cancelled performances between July 2 and July 20 after one of the musical ride horses contracted a "low-grade" case of Streptococcus Equi, an equine bacterial infection commonly known as strangles.

Though it is of no risk to humans, the Mounties say the upper-respiratory infection is very contagious to horses and can be carried by humans working with one horse, then contacting another.

It is fatal in about 10 per cent of cases.

Ride officials say they're taking every precaution to protect their horses, as well as others.

The ride's veterinarian advisers recommended the horses be isolated at the RCMP stables in Ottawa, where public contact has been restricted.