Advice on proceedings of the WSAA strategic workshop on viability tests and genetic typing of Cryptosporidium.

July 2000

Executive summary

The Water Services Association of Australia (WSAA) has outlined a strategy for the development of guidelines setting out conditions required to inactivate Cryptosporidium oocysts and for improved hazard analysis, health surveillance and incident management through the application of predictive molecular epidemiology. To facilitate achievement of these aims, a workshop was held in Sydney in March 2000 to explore issues of viability measurement (specifically, capability of infecting a human) and genetic typing as a tool for strain identification and molecular epidemiology of cryptosporidial infections.

Collaborative approaches to viability studies and genotyping of Cryptosporidium were proposed within Australia and internationally. The UK should be involved, since advances in surveillance and epidemiology of cryptosporidiosis, and the creation of a national reference collection of oocysts, provide an excellent base for expanded studies. Validated viability, typing and infectivity determinants are required in the UK and elsewhere to provide sensitive and specific methods for environmental samples and application to risk assessment. Cell culture methods should be investigated since they appear to offer a good model for human infectivity with genotype 2, and the opportunity for comparison of cell culture with human infectivity trials involving genotype 1 should be created. UK representation at the forthcoming ASM Cryptosporidium Conference in October 2001 is essential for transfer of technology both ways.

The work described in this report was funded by the Department of the Environment, Transport and the Regions. The Drinking Water Inspectorate was responsible for contract management.

Copies of this report may be available as an Acrobat pdf download under the 'Post 2000 Reports' heading on the DWI website.