PATHOGENIC ILLNESS INDEX | COMMENT AND FEEDBACK

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White water canoeing in sewage contaminated water produces an increased risk of gastrointestinal and other symptoms. By comparison with many other risk factors both in sport and in general life these symptoms are mild, non-life threatening and of short duration. A decision to go canoeing on sewage contaminated waters, even certain waters outside bathing water standards, would not appear to be irrational or excessively risky.

White water canoeing is a high contact activity with a high (relative) risk of illness symptoms, whilst marathon canoe racing has a lower risk, even on more polluted waters.

Drinking or eating whilst wet (ie before showering or washing your hands) increases the relative risk of illness.

It may be possible to assume that a group of expert canoeists will contain a higher proportion of people who have a high level of resistance to water-borne pathogens than a group of beginners, or a group of the general population.

The use of indicator organisms would appear to be helpful in long term studies to assess mean seasonal trends. They are of use for Water Companies and Regulatory Authorities who are attempting to devise long term policies to manage the quality of UK watercourses, or to sports managers who are looking at proposals to site a canoeing facility in a certain area. On a short term basis the massive localised temporal and spatial variability means that indicator organisms cannot be used by canoeists on routine basis to assess the exact risk from any particular site on that day.

Bacterial and viral pathogens come from many sources, including sewage works, storm culverts, and run-off from urban and rural land areas. It may be possible to estimate the likely risk from pathogenic microorganisms by assuming low, medium, high and very high risk in weather conditions of average summer, average winter, winter storm and summer storm respectively.

Research should be carried out to assess the risk to canoeists of canoeing in summer and winter storm conditions.

Canoeists travelling to areas with little human faecal pollution should still consider the risk from microbial pathogens if a river has rainfall run-off from vegetated or forested areas with high animal populations.

Leptospira and cyanobacteria are the only organisms with a realistic potential to cause fatal disease to canoeists in the UK. Although advice is given to canoeists about Weil's disease in the British Canoe Union Yearbook, no advice is given about blue green algae. Such advice might be helpful bearing in mind the potential seriousness of any infection.

Statutory Water Quality Objectives for Water Contact Activities provide a means of setting water quality standards for inland waters, and Sports Governing Bodies should lobby for their introduction.