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Stomach Bug

Commonly known as a tummy bug or stomach flu, the medical term for a stomach and bowel infection is gastroenteritis. There are two main causes of gastroenteritis in the UK adult population, namely norovirus (or the winter vomiting bug) and bacteria in food that cause food poisoning, such as salmonella, E. coli, listeria and campylobacter.

The main symptoms of gastroenteritis – regardless of the cause – are diarrhoea and vomiting. Other symptoms may also include stomach cramps, aches and pains, headache and a raised temperature. An estimated one in five people develops gastroenteritis in a year in the UK, but most cases are relatively mild. And while the symptoms differ slightly from one case of gastroenteritis to the next, the good news is that the vomiting should only last for 24-48 hours, though you may continue to have diarrhoea for another couple of days. You can find some diarrhoea remedies here.

Dehydration danger

The symptoms of gastroenteritis aren’t exactly pleasant, but they can have a more serious affect on your body’s absorption of water and salts, which can lead to dehydration. So it’s important to keep sipping fluids while you have a tummy bug, even if you can’t keep anything down. Water is ideal, but you could also try drinking fruit juice or thin soup if you’re feeling up to it.

Young children and elderly people are particularly susceptible to dehydration from diarrhoea compared with other adults. So if you’re looking after someone with gastroenteritis who’s very young or old, it’s important to pay attention to early warning signs such as a dry mouth, dark-coloured urine, lack of energy and light-headedness. If a young child or elderly adult has any of these signs, or if they have diarrhoea symptoms that persist for longer than 24 hours, call their GP’s surgery for advice.

Plain, simple foods

Once you feel like eating again, have something small and simple, and avoid any rich, sugary, fatty or spicy foods that may aggravate your symptoms. Choose regular small amounts of plain foods instead of three big meals a day. Then when you haven’t had any symptoms for 48 hours, you can go out again without the risk of infecting anyone else

What is norovirus?

It’s often called the winter vomiting bug because it’s more common during the cold season. But the truth is, you can catch norovirus at any time of year.

According to the NHS, between 600,000 and a million people are affected by norovirus in the UK every 12 months. And because the virus is constantly changing, you can get it more than once (according to the NHS, there are at least 25 different strains of noroviruses known to affect humans). Norovirus is one of the viruses that can cause the stomach bug gastroenteritis. Your symptoms can start very suddenly, usually a day or two after you become infected, and may last for a few days. Unfortunately there’s no cure for norovirus, so if you become infected you have to let it run its course. Thankfully, it’s not usually harmful and you should make a full recovery without having to see a doctor.

One of the important things to bear in mind if you do become infected is to avoid going out and spreading the infection. If you go to see your GP, there may be little they can do for you while you have the virus, and you may infect other patients. So stay at home and drink plenty of water (taking frequent small sips may help you to keep it down). Then when you do feel like eating again, go for something that’s easily digested, such as soup, bread, rice or pasta.

If you’re looking after someone who has norovirus, reduce your own risk of catching it by washing your hands frequently and thoroughly, and don’t share towels or flannels with the person who has the virus. Also wash any clothes or bedding that may have been contaminated, and spray surfaces that may be infected with a suitable disinfectant, including the toilet and surrounding area.

When should you see your GP?

Most people with norovirus don’t need to see their doctor and should stay away to avoid spreading it. But if your symptoms last longer than a few days – or if you already have a serious illness – call your GP’s surgery and ask for their advice.

You should also see your GP if you’re severely dehydrated. Here are the symptoms to look out for:

  • Severe thirst

  • Dry, wrinkled skin

  • Inability to urinate

  • Irritability

  • Sunken eyes

  • Weak pulse

  • Rapid heartbeat

  • Cold hands and feet

  • Seizures


How to prevent travellers’ diarrhoea

Going abroad for a summer holiday is something most people look forward to. But there’s always a risk you could come back with more than a few souvenirs. Indeed, one of the most common travel health problems, especially for those travelling to places such as Asia, Africa, the Middle East and Latin America, is gastroenteritis – or to give the condition it’s more popular name, travellers’ diarrhoea.

Most often caused by bacteria in local water, travellers’ diarrhoea can also be caused by a virus such as norovirus or rotovirus, or – more rarely – a parasite found in contaminated food and water, such as giardia. It can affect an estimated 20-60 percent of people during their travels (i), usually within the first week or two of arriving at their destination.

Watching what you eat and drink can help. Here are some tips to keep you stomach-bug free:

  • As a rule, if you're travelling abroad – even if it's only in Europe – stick to bottled water, even for things like brushing your teeth. Where possible, choose sealed carbonated water.

  • Avoid drinks with ice, as the ice may well have been made from tap water. Hot drinks, however, are generally safe if you can guarantee the water has been boiled properly.

  • Don't eat any raw fruit or vegetables that you haven't peeled and washed yourself. Also avoid green salads, unless you’re certain the ingredients have been washed with treated, boiled or safe bottled water.

  • Finally, if you or your fellow travellers develop a bout of traveller’s diarrhoea, wash your hands frequently to avoid spreading the infection to other people (if you’re going to a remote destination, consider taking a supply of hand sanitising gel or wipes in case you don’t always have access to soap and water).

Food safety: what you should know

According to the Food Standards Agency, there are about 850,000 cases of food poisoning in the UK every year. These are caused by eating food contaminated with bacteria such as campylobacter, salmonella, E. coli and listeria, or a virus such as norovirus.

You don’t have to go overseas or eat at a dodgy restaurant to end up with a bad case of food poisoning. In fact, you don’t even have to leave the comfort of your own home to come down with the symptoms of gastroenteritis, such as feeling sick, vomiting, diarrhoea and stomach cramps.

Foods that are typical sources of the organisms that cause food poisoning include raw shellfish, raw eggs, raw meat and poultry and even milk. If you don’t store, handle or cook these foods thoroughly at the right temperature, they can turn into breeding grounds for harmful bacteria. Cooking your food thoroughly, storing it correctly and practising good hygiene will go a long way to making sure you avoid getting food poisoning at home. Here’s what you should do:

  • Make sure your food is cooked thoroughly and hot all the way through

  • Follow the storage instruction on the packet, and store cold foods in a refrigerator at a temperature below 5ºC

  • Don’t leave cooked foods out at room temperature for too long

  • Avoid cross-contamination of food, especially when using utensils like spoons, knives, work surfaces and chopping boards

  • Store uncooked poultry/meat on the bottom shelf of the refrigerator to avoid the juices dripping onto other foods

  • Cool left-over food quickly, then cover and refrigerate

  • When reheating food, make sure it’s piping hot all the way through, and don’t reheat more than once

  • Always wash your hands thoroughly with hot water and soap before eating and when handling food during cooking (especially raw meat), as well as after going to the toilet or touching bins or pets

  • Change your dish cloths and tea towels regularly, even if they look clean

  • Avoid preparing food if you have symptoms such as diarrhoea or vomiting

Tummy bug remedies

Most cases of mild diarrhoea clear up without any treatment, and adults should see an improvement after two to four days. But there are a couple of remedies that may help to reduce the severity of diarrhoea and shorten the amount of time it lasts.


Available in capsules, loperamide helps to slow down the movement of muscles in the intestines. This means more water is absorbed in your gut, making your stools firmer. If, however, you have gastroenteritis and you’re still feeling sick or vomiting, check with your GP before taking loperamide.

Bismuth subsalicylate

Medicines or tablets containing bismuth subsalicylate may also help to control diarrhoea and are also used to treat indigestion, heartburn, upset stomach and nausea. They may not be suitable if you’re taking other medicines, such as aspirin or other salicylates, anticoagulants (medicines that thin your blood), diabetes, tetracycline antibiotics and medicines that treat gout.

Rehydration solutions

On the other hand, if you’re worried about becoming dehydrated you can take an oral rehydration solution, a sachet of powder that you dilute in water. Recommended for people who have underlying health problems and those who are frail or aged 60 and older, rehydration drinks include salts and sugar that help your intestines absorb water, but they don’t help reduce diarrhoea.

Natural relief

Meanwhile, natural supplements may help in a variety of ways.  Supplements containing live bacteria such as L acidophilus, L casei, S boulardii and B bifidus may act as a barrier against any potentially harmful bacteria that pass through your digestive system and work to prevent the growth of harmful organisms.

Numerous clinical studies suggest taking supplements of live bacteria may be an effective way to protect against a variety of gut and intestinal problems. Researchers around the world have tested their abilities, with test results suggesting that live bacteria may help relieve diarrhoea (ii), including travellers’ diarrhoea (iii).

Alternatively, soluble fibre supplements that contain substances such as fructo-oligiosaccharides  may help because they stimulate the growth of beneficial gut bacteria. There is also some evidence that live bacteria may support the immune system (iv), which may be valuable when you have a tummy bug. Other supplements that may help to enhance immune function include vitamin C and multivitamin and mineral formulations that include good levels of vitamins C and D, zinc and selenium.

Meanwhile, as a preventative, you may also want to consider taking a garlic supplement for its anti-viral effect. In one study, for instance, the active ingredient in garlic called allicin was found to have antibacterial, antifungal, antiparasitic and antiviral activities, including against certain strains of E coli (v).

Diarrhoea and vomiting can be extremely uncomfortable experiences, but the advice set out in this article should help you to manage the symptoms of gastroenteritis. For more information about other common health conditions, feel free to visit our health library


  1. , Management of travellers' diarrhoea. BMJ. ;337:a1746. doi: 10.1136/bmj.a1746.

  2. , et al. Probiotics for treating infectious diarrhoea. Cochrane Database Syst Rev ;(2):CD003048.

  3. , . Prevention and treatment of traveler's diarrhea: a clinical pharmacological approach. Chemotherapy. ;41(suppl 1):48-81.
    , , , et al. Efficacy of Lactobacillus GG as a diarrheal preventive in travelers. J Travel Med. ;4:41-43.

  4. , , , et al. Enhancing immunity by dietary consumption of a probiotic lactic acid bacterium (Bifidobacterium lactis HN019): optimization and definition of cellular immune responses. Eur J Clin Nutr. ;54:849-855.

Disclaimer: The information presented by Nature's Best is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications.

Our Author - Christine Morgan


Christine Morgan has been a freelance health and wellbeing journalist for almost 20 years, having written for numerous publications including the Daily Mirror, S Magazine, Top Sante, Healthy, Woman & Home, Zest, Allergy, Healthy Times and Pregnancy & Birth; she has also edited several titles such as Women’ Health, Shine’s Real Health & Beauty and All About Health.

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