Continuous monitoring for Cryptosporidium--a novel approach to public health protection.

Regulations requiring water utilities in England and Wales to carry out continuous monitoring for Cryptosporidium in treated water were introduced in June 1999. The rationale of the Regulations and the technical basis for the sampling and analysis are reviewed. The results of the first nine months of monitoring are summarised and compared with other equivalent data sets. The impact of the Regulations on water utilities operational practices and the implications for public health protection are discussed.