A protozoan called cryptosporidium has infected the water supply in parts of County Galway in wester Ireland. The parasite can cause stomach pain and diarrhoea. As a result, the Catholic Church in the area has decided to bless 3,000 bottles of spring water instead of tap water on Holy Saturday, that is, 7 April.
Although the water is meant to be used externally in order to obtain a blessing, some people tend to drink it, according to a priest at Tuam Cathedral (BBC).
Sensible precaution; reminds me of the ultraviolet treatment of water at the Zamzam well.