Health expert says heatwave habit could leave you with bloody diarrhoea

A woman bathing in the River Etive in Glen Etive, Highlands, with a waterfall and a mountain in the background
-Credit: (Image: Getty)


After enduring a rather dreary June, the UK is set to sizzle under a 'scorching' 10-day heatwave, with temperatures potentially soaring to 40C in some regions due to an approaching 'heat dome'.

The spike in mercury has previously fuelled a surge in outdoor swimming across the nation, with the Outdoor Swimming Society noting that around 7.5 million Brits take to rivers, lakes, lidos, and seas annually. Membership of the society has skyrocketed, with an increase of 170,000 in recent years.

Yet, as the country braces for the sweltering conditions, health experts are raising the alarm for those keen on taking a dip outdoors. The staggering volume of sewage discharged into British rivers and coastal waters each year poses a significant threat.

Last year alone, there were 464,056 instances of sewage spills in UK waters, prompting medical professionals to caution about the potential severe health impacts of ingesting contaminated water.

Gut health expert Dr Alasdair Scott from Selph warns of the dangers lurking in our open waters: "When sewage is spilt into open water, it means it is highly likely to contain coliform bacteria, which is basically an E. Coli. The bacterias come from faeces and can cause very serious health problems if the water is swallowed, including traveller's diarrhoea and renal failure.", reports Devon Live.

"Symptoms of these conditions would manifest relatively quickly and would include abdominal bloating and cramps, nausea and vomiting, an urgency to go to the toilet, loose, watery stools and a mild temperature."

Man with yellowish eyes and skin caused by jaundice from an infection
Man with yellowish eyes and skin caused by jaundice from an infection -Credit:Getty

However, Dr Scott explains that parasites like Giardia, which are often found in contaminated surface waters, can cause much more severe problems.

"The Giardia parasite can cause very serious health problems if it enters the human body. These range from abdominal pain and bloating, to bloody diarrhoea that can last for weeks or even months."

"Bacteria such as Leptospira can also be found in contaminated water, which can lead to severe conditions such as Weil's disease or Leptospirosis. Symptoms are more general and include fever, headache and muscle aches. Dr Scott said. "Leptospirosis can affect your liver, and can even lead to jaundice, where your eyes go yellow. Weil's disease has quite a long incubation period too, so you could be fine for four weeks and then develop those kinds of symptoms quite abruptly."

Dr Scott adds: "If you think there's a chance you've swallowed water that is contaminated water and you begin to suffer from any of these symptoms, it's important to conduct a gut parasite, worm and bacteria test as soon as possible. You'll then be advised on next steps whether your test is positive or negative. It's also important to speak to your GP if you are seriously concerned."

"Each year, the government monitors popular outdoor swimming spots across the country and labels them as a 'designated Bathing Water spot' if they meet the necessary quality control measures. There are a total of 451 official 'Bathing Waters' across the UK, most of which are coastal, although it does include some lakes and rivers too."

"Once the waters receive this status, they undergo regular monitoring to ensure bathers have up-to-date information on the quality of the water, and actions will be taken if minimum standards aren't being met."

"My advice would be to check the government's Bathing Waters list before you decide to go outdoor swimming this summer, so you can have the reassurance that your chosen spot is safe and clean enough to swim in. Or, stick to public outdoor pools or lidos rather than wild swimming spots, which are much more likely to be regularly treated."

Join the Daily Record's WhatsApp community here and get the latest news sent straight to your messages.