Some 6,400 householders and businesses on a precautionary boil water notice in Westport are waiting to hear if a water supply or system contamination is the source of a local cryptosporidiosis outbreak.
Eight cases of the diarrhoeal illness, caused by a microscopic parasite, have been reported in the Westport area to the HSE in recent weeks.
Seven of the eight cases identified were in the area serviced by the Westport Public Water Scheme, sourced from Moher Lough.
This prompted the HSE to advise Irish Water and Mayo County Council to issue a precautionary boil water notice in the interests of public health on Wednesday afternoon.
A spokesperson for Irish Water said yesterday that, so far, no cryptosporidium has been detected in Westport’s water through routine sampling, the most recent of which relates to last Friday.
Further water sampling results are due this afternoon (Friday ).
However the spokesperson said the boil water notice status may not necessarily change, even based on those results.
“People need to follow the boil water notice until otherwise advised,” she said. “Irish Water is reviewing the situation in conjunction with the HSE.”
It is also important to note that drinking water is just one source of cryptosporidiosis, added the spokesperson.
As one of Ireland’s premier visitor destinations, tourism operators in the town will want to hear as soon as possible how long the costly boil water notice is likely to last.
The water supplies affected by the notice are the Westport public water supply and the Ballinlough, Cloghan, Brackloon/Bohea, Cushlough, Farnaught, and Rosmoney West group water schemes.
An Taoiseach Enda Kenny said he spoke to Irish Water on Wednesday evening and the company is confident the issue is in the system and not at source.
“Westport is fortunate in that it is supplied from two points — Westport and Lough Mask — and so once testing is completed to the satisfaction of the HSE there is the possibility of restoring some supply to the town,” said Mr Kenny.
Irish Water and Mayo County Council are in the process of providing an alternative supply from Lough Mask to parts of Westport to minimise the number of customers affected by the notice.
Cryptosporidium is a microscopic parasite, found mainly in the faeces of human or animals, and causes the illness, cryptosporidiosis.
Symptoms of cryptosporidiosis typically last for one to two weeks but can last for up to a month.
In certain more vulnerable people, such as young children, the elderly or those with an impaired immune system, cryptosporidiosis can be much more severe.
Under the boil water notice, drinking water, drinks made with water, water used in the preparation of salads and similar foods, which are not cooked prior to eating, water for brushing teeth, and for making ice, should all be boiled vigorously.
It is safe to bathe in the water but Mayo County Council and Irish Water advised caution should also be used when bathing children to ensure they do not swallow bathing water.
Irish Water said it will keep people updated as any further information becomes available.
Anyone sufffering from diarrhoea for more than two days should contact their GP.