Is diarrhoea a symptom of COVID-19?

Data from millions of ZOE Health Study app contributors has shown that diarrhoea can be a symptom of COVID. Here’s how to spot it and what it feels like.

What is diarrhoea like in COVID?

Diarrhoea caused by COVID is similar to the upset tummy you might get from a regular stomach bug, such as rotavirus or norovirus, and usually clears up by itself. 

We think COVID causes diarrhoea because the virus can invade cells in the gut and disrupt its normal function. 

COVID can be transmitted through poo and contaminated surfaces or hands. It’s critically important to wash your hands thoroughly and regularly clean bathrooms if you, anyone you live with or someone you’re caring for has diarrhoea to prevent the infection spreading. 

What other symptoms of COVID-19 are common alongside diarrhoea?

Early in the pandemic we found that there was a distinct cluster of gastrointestinal COVID-19 symptoms, including headache, loss of smell, loss of appetite, diarrhoea, sore throat, chest pain and no cough.

Diarrhoea was also associated with a greater risk of needing hospital support, particularly among people also reporting abdominal pain and unusual muscle pain.

There was a rise in people reporting gastrointestinal symptoms in the UK through January 2022. Some of this was related to the Omicron wave, but there also seemed to be a wave of other non-COVID tummy bugs going around too.

Diarrhoea is an early sign of COVID, starting on the first day of infection and building in intensity during the first week. It usually lasts for an average of two to three days, but can last up to seven days in adults.   

Some people can suffer from ongoing bouts of COVID-related diarrhoea, and these are commonly reported in people with Long COVID.

How common is diarrhoea in COVID?

In the Alpha wave, nearly a third of adults aged over 35 (30%) reported experiencing diarrhoea with COVID.

That’s fallen with subsequent variants and vaccination, with up to one in five people (16-20%) experiencing diarrhoea with either Delta or Omicron if they have had either two or three doses of the vaccine.

What should I do if I have diarrhoea and think it might be COVID?

It’s vital that people know the current symptoms of COVID now that restrictions have lifted and access to testing has changed.

If you have diarrhoea it could be COVID, especially if you have other symptoms like a headache and loss of appetite. 

If you have diarrhoea, it’s important to keep drinking and eating if you can. The NHS has more advice for treating diarrhoea. 

Diarrhoea increases the risk of spreading infection to others in your household, so it’s essential to wash your hands thoroughly and keep bathrooms clean and tidy. 

Download the ZOE Health Study app to log your symptoms. 

Whether you have COVID or any other bug, please be considerate by staying home when you’re ill and wearing a high quality FFP2 or FFP3 mask when you go out, to avoid spreading your germs to others who may be more vulnerable.

Stay safe and keep logging.