Parents have been urged to be vigilant as a fresh outbreak of Weil’s Disease plagues streams and lagoons across the country.
The killer bug, spread by rats, can be picked up through just a tiny cut or scratch, or even the lining of the mouth, from a single splash in infected water.
And anyone exposed to the disease could die within days, medics have warned.
At least four Brits are thought to have succumbed to Weil’s Disease since 2009, including gold medal Olympic rowing champion Andy Holmes, partner of Sir Steve Redgrave.
Speaking after his tragic death, Andy’s brother, Simon, said: “There was an overwhelming, serious and severe reaction to some kind of infection.
“The working diagnosis that the clinicians were working on was Weil's disease. It was very sudden.”
Many other victims have been left battling life-changing conditions after catching the bacterial infection.
Swimmer Billy-Joe Humphries told how he needed emergency medical assistance after taking a dip in water contaminated by rat urine at Warleigh Weir, near the Wiltshire / Somerset border, Wiltshire 999s reports.
Billy-Joe posted on Facebook: “Beware friends and family, on Tuesday I went to Warleigh Weir in Bath to swim.
“The next morning I woke up with terrible flu symptoms. Thought it was just a summer cold. Last night I never felt so ill in my life, I called 111 to get advice they sent an ambulance, they booked an emergency appointment for me to get to the doctors.”
He told how he was prescribed medication for a chest infection, adding: “Just beware before you go swimming in lakes / rivers, believe me it’s not nice at all.”
Weil’s disease, also known as Leptospirosis, is spread in the urine of infected animals including mice, cows, pigs and dogs, as well as rats, according to the NHS UK website.
You can catch it if soil or fresh water (such as from a river, canal or lake) containing infected pee gets in your mouth, eyes or a cut – usually during activities such as kayaking, outdoor swimming or fishing, the NHS states.
Symptoms include a fever, headache, sickness, aching muscles and joints and a loss of appetite.
Seek urgent medical assistance if you have symptoms including yellow skin and eyes, swollen ankles, feet or hands, chest pain, shortness or breath or coughing up blood.
It comes as Britain is hit by a swarm of vampire horse-flies in the sweltering heatwave.
And a bug outbreak in the Canary Islands has left tourists at risk of pneumonia.
