The risks of mixing with sewage

From upset tummies to liver damage, discover how sewage pollution is making us sick to our stomachs… literally.


Why does sewage pollution make us sick?

Human sewage contains bacteria and viruses (also known as pathogens) that have previously grown inside another person or animal. This means that they are accustomed to the human body and can live there quite comfortably. The vast majority of pathogens cause no harm. However, some can cause serious infections.

When surveyed, the majority (55%) of Brits who have tried wild swimming or sports in UK waters reported falling ill afterwards (on at least one occasion), with half admitting they’re scared to swim outside due to pollution. The presence of sewage might not stop the rest of us from hitting the surf regularly, but it’s important to understand the kinds of sickness that can be caused by entering polluted water. That way you can keep an eye out for symptoms and make educated decisions about treatment.


How does sewage pollution make us sick?

Sewage pollution can cause a whole range of illnesses. Check out our latest Water Quality Report to find out what people are reporting to us. And read on to learn more about the kinds of illnesses you should be aware of that can be caused by sewage pollution.

Cause: Swallowing water contaminated with bacteria or viruses can cause stomach gastroenteritis – a.k.a. stomach upsets. These unfriendly organisms – introduced to your insides via swallowed seawater – bed down and grow inside your digestive system, which causes the stomach, small intestine, and occasionally the colon to inflame.

Symptoms: Gastroenteritis typically results in vomiting, abdominal cramps and diarrhoea for around 12 to 72 hours. Viral infections usually resolve quicker than bacterial ones, which can last up to four weeks.

Treatment: The vast majority of people with gastroenteritis get better without treatment and don’t need to take medication. The symptoms cause you to lose a lot of fluid, so dehydration is a side effect to watch out for – sustained sipping is the order of the day! It’s generally uncommon for adults to need admission to hospital for intravenous fluid to replace the fluid they have lost when suffering from gastroenteritis.

Causes: Cuts and grazes on our skin allow bacteria and viruses from sewage pollution to enter the body, which can then result in an infection.

Symptoms: A painful and itchy rash can develop, with the skin becoming hot and swollen. The wound may also start weeping pus (yuck), which is the product of your immune system’s attempt to destroy the multiplying bacteria.

Treatment: If left on its own and kept clean and dry, a minor skin infection should get better on its own. But some can progress and make you feel unwell or cause a fever. Cleaning the area thoroughly is very important, and if you’re worried, seek medical advice.

Causes: The longer that water from the sea and rivers hangs about in your ear, the higher chance you have of developing an outer ear infection. This is why people who suffer from surfer’s ear are prone to infection, because it slows down the ear’s ability to drain water. The more bacteria and viruses present in the water, the higher the chance of infection.

Symptoms: Ear infections cause pain in the affected ear and can result in temporary hearing loss. If left untreated, the infection can become extremely uncomfortable and spread to the skin around the ear and on the face. This can make you feel extremely unwell and cause a fever.

Treatment: Don’t be tempted to unleash the cotton buds, as cleaning inside the ear can irritate the skin and increase the chance of infection. Hearing loss resolves once the infection clears. Unfortunately, antibiotics don’t make much of a difference to a simple outer ear infection, but they can help prevent a persistent one from spreading to surrounding skin. Wearing earplugs designed for surfing greatly reduces the chances of initial infection.

Causes: Sewage water contains bacteria and viruses that are able to infect any inflamed area around your eye. Adenoviruses in particular have a reputation for causing nasty eye infections.

Symptoms: The tissue surrounding the eye (the conjunctiva) becomes red and swollen, causing conjunctivitis – which results in watery, weepy eyes. Eye infections are often very uncomfortable – it can sometimes feel like you have small grains of glass in the eye. Ouch. Often infection starts in only one eye, but is easily spread to the other.

Treatment: Eye infections are easy to treat with eye drops, but if left untreated they can progress and become extremely unpleasant. If you have difficulty seeing or reading normally with the affected eye, or there is pain during eye movement, then you should seek urgent medical attention. Regular hand washing is important to prevent the transfer of infection to your other eye – and the eyes of others!

Causes: Viruses found in contaminated water can infect your upper airway. The common cold is an example of this.

Symptoms: A throat infection causes pain on swallowing. It is extremely common to suffer from symptoms of a common cold after surfing or swimming in sewage-contaminated water.

Treatment: The illness is usually mild and resolves after a few days.

Causes: If water is contaminated by sewage, pathogens can be inhaled and have the potential to infect the lungs and airway. Due to a lack of research it is not known how common a problem chest infections are for people who swim or surf in sewage-contaminated water.

Symptoms: Chest infections cause coughs and can result in difficulty in breathing. An infection can be extremely severe and can make you very unwell.

Treatment: If your symptoms continue to get worse, it’s best to seek medical advice to avoid the development of a serious medical condition.

Causes: Hepatitis A is a virus frequently found in sewage. Sewage workers are advised to vaccinate themselves against the virus. So too are surfers who regularly surf in sewage-polluted water.

Symptoms: Symptoms include a reduced appetite, feeling nauseated, vomiting, fever, shivers, weakness, a headache, general aches and pains, and abdominal pain. Your stools (that’s the medical term for your poo) can become pale, and your urine can become dark. If Hepatitis A is able to establish itself properly, it can make itself at home in your body for weeks – which is not good news. During this time the liver may deteriorate significantly in its ability to perform its normal functions. Liver failure, although only occurring in 1% of cases of Hepatitis A, is an extremely dangerous condition. If hepatitis becomes severe it can result in confusion, a reduced level of consciousness, or even a coma.

Treatment: The time the virus takes to reveal itself can take from 15 to 50 days. During this time, the virus is replicating in the liver, and shedding itself into your faeces (another term for your poo). In children the disease is usually mild, but can be much more serious and prolonged in adults. Virtually all people that suffer from Hepatitis A go on to make a full recovery with treatment. If you are concerned that you may have contracted hepatitis, speak to your GP as soon as possible.

Causes: E. coli is spread by the ‘faecal-oral’ route. We won’t dress it up – basically, any way that faeces can find its way into your mouth has the potential to spread E coli. Of course, this includes swimming in sewage-contaminated sea and river water. E. coli is often present in your gut, but some strains produce a protein that acts as a toxin in the human body.

Symptoms: This toxin causes abdominal pain and aggressive diarrhoea and vomiting. If it progresses, the toxin can cause damage to blood vessels in the skin, causing a distinctive rash. It can also spread to the kidneys resulting in serious and potentially life-threatening illness. How E.coli affects you will depend on the strain, and whether it is able to out-compete the E. coli that already exists in your gut. You may get off lightly, with slightly runnier stools. Only a few strains of E. coli have the potential to cause significant harm.

Treatment: If you suspect you have E. coli, please seek medical assistance as soon as possible. 

I got sick swimming in sewage pollution. How do I report it?

Firstly, if your symptoms are serious, please seek medical assistance to ensure you make a full recovery.

Secondly, report the incident to the environmental regulator so they can investigate any pollution instances. Find out how to report an incident here.

At SAS, we’re collecting sickness case studies to build up a bank of evidence that we can use to hold water companies and the Government to account. Download the Safer Seas and Rivers Service or submit directly through our website.