Hundreds of mountain bikers competing in separate races in British Columbia and Wales in the past year were stricken by campylobacter, apparently from contact with feces-laden mud.

Now, the National Public Health Service for Wales (NPHS) and Environmental Health officers at Powys County Council have concluded the Welsh outbreak was probably caused by campylobacter, spread to the cyclists by mud which was contaminated with sheep feces.

The report acknowledged that, given the nature of mountain bike events, it would be impossible to eliminate the risk of catching such an infection, but made the following recommendations:

* Participants should avoid using soiled drink and food containers
* Pre-packaged food should be eaten out of the wrapper
* Where possible, hands and utensils should be washed before consuming food and drinks
* No open food should be served at events.
* Drinks produced in large volumes for consumption by participants should be dispensed using a method which does not require the repeated immersion of utensils.
* Organisers should consider providing facilities to wash hands and water bottles with clean, running water
* Wherever possible, courses should be re-routed to avoid areas which are heavily contaminated with animal faeces
* Mountain bikers, particularly those who are vulnerable to infection, should be alerted to the potential risk of acquiring zoonotic illnesses from participation in events which cross land used by agricultural and other animals.

 To comment on the report, email bikes.outbreak@nphs.wales.nhs.uk.