THE number of stomach bug cases linked to contamination of the Ribble Valley water supply has risen to 55.

Drinking water in Clitheroe was declared safe two weeks ago - but then North West Water backtracked and urged people to boil water before use.

Now East Lancashire Health Authority says it expects new cases of cryptosporidium will continue to be reported.

The bug, which causes diarrhoea and stomach pains, meant 10,000 households in Clitheroe had to boil their drinking water.

A health authority spokesman said there were two reasons why cases had continued to be reported.

"Firstly, cryptosporidiosis has a long incubation period (the time between acquiring the organism and developing symptoms of the infection) which can be up to about three weeks," he said.

"Secondly, the infection is readily spread from person to person by direct contact so there will be some continuing spread within the community. Good personal hygiene is very important in preventing this secondary spread."

The health authority said that overall, the results of recent water sampling had been good with low concentrations of the bug found in a small number of samples - a situation not unusual in routine water samples.

The spokesman said the levels did not pose any significant risk to health and the outbreak control team would continue to monitor the situation.

The health authority had claimed the outbreak was probably due to new lambs, who carry the bug in their gut and faeces.

Dr Stephen Morton, the authority's director of public health, said heavy rain could have washed down fields and into the springs which feed Lowcocks water treatment centre in West Bradford.

But farmers said all pregnant sheep had been taken off the fells weeks ago so their lambs could be born near the farms.

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