As " low levels " of the parasite remain in the water supply further tests are needed before the " all clear 2 and it’s not yet known how traces got into the treatment works, or if anyone has been infected ( incubation period 5 – 10 days ).
• Cryptosporidiosis may not be the first " bug " to come to mind as a cause of diarrhoea, but it does cause a few thousand cases each year in the UK – and has a worldwide distribution. It’s a protozoan – two major species are C. hominis ( humans ) and C. parvum ( in many species including cattle in the UK and carabao in the Philippines ). Infection is usually from faecally-contaminated water or food.
The cysts ( “ oocysts “ ) are infectious at low doses ( 10 – 30 for humans ) - they attach to and enter cells lining the small bowel, but are resistant to treatment. They are also resistant to chlorine in swimming pools ! They ARE killed by boiling water.
• The parasite may be transmitted from livestock ; personal contact with affected individuals ( who may not have symptoms ) ; food such as raw milk, meat, shellfish, fruit and vegetables ; contaminated swimming pools or water supplies.
• It typically causes low-grade fever and diarrhoea. People most at risk are children, or adults with immune deficiency such as HIV/AIDS. IF symptoms persist and they are unusually severe, treatment may be difficult, because the drugs available are of unproven benefit ( and are not licensed in the UK ).
• However, to keep up the " good news theme " on the Forum, in healthy individuals the disease is self-limiting and just needs standard fluid replacement until they recover. Hopefully the only people likely to need extra toilet paper are the United Utilities and Public Health individuals responsible for detecting and preventing infection with this nasty parasite
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