Food poisoning when do symptoms occur

The main treatment and prevention strategy for food poisoning is to rest and replace lost fluids and electrolytes by:. The following may worsen symptoms during gastroenteritis episodes: fatty, sugary, or spicy foods, dairy products, caffeine, and alcohol. To avoid the dangerous and potentially fatal effects of dehydration from diarrhea, oral rehydration salts ORS are recommended for vulnerable people for example, infants and children, adults over 65 years of age, and people with weakened immunity.

Gro Harlem Brundtland — it reduced the number of deaths every year among children with acute diarrhea, from 5 million to 1. In developed countries, while the threat of death is smaller, rehydration is nonetheless important.

Salt, glucose, and minerals lost through dehydration are replaced by sachets of oral rehydration salts available from pharmacies and online. It is important to get the right concentration, as too much sugar can make diarrhea worse, while too much salt can be extremely harmful, especially for children.

A more dilute solution for instance using more than 1 liter of water , is preferable to a more concentrated solution. Store-bought products like Pedialyte and Gatorade also help restore electrolytes and increase hydration. Talk to a doctor before taking anti-diarrhea medication as some infections may get worse with anti-diarrhea medicines. One study found that the use of probiotics in children hospitalized for acute gastroenteritis shortened their hospital stay by an average of 1.

Specifically, there is some evidence to support the use of the following strains of beneficial bacteria in the treatment of gastroenteritis in children, alongside the use of oral rehydration solutions without dietary restriction:. This is a new area of study, so there may be more research about using probiotics to treat gastroenteritis in the future. These symptoms can occur in any combination; they generally have a sudden acute onset, but this, and symptom severity, can vary.

The onset of symptoms after eating contaminated food can be within a few hours , but the incubation period can also be much longer, depending on the pathogen involved. Vomiting usually happens earlier on in the disease, diarrhea usually lasts for a few days, but can be longer depending on the organism that is causing the symptoms.

In addition to the classic symptoms above, food poisoning and gastroenteritis can also bring about:. The type of gastrointestinal symptoms are a clue to the type of infection — viral infection generally produces diarrhea without blood or mucus, and watery diarrhea is the prominent symptom. Conversely, mucus and blood are more often seen in bacterial diarrhea. Norovirus can cause acute onset of vomiting, especially in children.

One of the dangers of food poisoning and gastroenteritis — especially in very young, old, or otherwise vulnerable people — is the loss of fluids resulting from diarrhea and vomiting, which can lead to dehydration.

Dehydration can, however, be prevented. Individuals should seek out medical care if they get lightheaded, have bloody diarrhea, fevers, are over 65, have multiple medical problems, are pregnant, or if symptoms do not get better in a few days.

Food poisoning and stomach flu have similar symptoms, but stomach flu is always caused by a virus, for example, the norovirus. Usually begins suddenly and lasts for less than 24 hours. Vomiting and fever are not common. Common food sources: Beef or poultry , especially large roasts; gravies; dried or precooked foods.

Salmonella Symptoms begin 6 hours to 6 days after exposure: Diarrhea, fever, stomach cramps, vomiting Common food sources: Raw or undercooked chicken , turkey, and meat; eggs ; unpasteurized raw milk and juice; raw fruits and vegetables Other sources: Many animals , including backyard poultry , reptiles and amphibians , and rodents pocket pets.

Clostridium botulinum Botulism Symptoms begin 18 to 36 hours after exposure: Double or blurred vision, drooping eyelids, slurred speech. Difficulty swallowing and breathing, dry mouth.

Muscle weakness and paralysis. Symptoms start in the head and move down as the illness gets worse. Common food sources: Improperly canned or fermented foods , usually homemade. Prison-made illicit alcohol pruno. Common food sources: Raw or undercooked ground beef, raw unpasteurized milk and juice, raw vegetables such as lettuce , raw sprouts , unsafe water. Cyclospora Symptoms begin 1 week after exposure: Watery diarrhea, loss of appetite, and weight loss. Common food sources: Raw fruits or vegetables and herbs.

Listeria Symptoms begin 1 to 4 weeks after exposure: Pregnant women usually have a fever and other flu-like symptoms, such as fatigue and muscle aches. Infections during pregnancy can lead to serious illness or even death in newborns. Other people most often older adults : headache, stiff neck, confusion, loss of balance, and convulsions in addition to fever and muscle aches.

More Information. This can occur when one food touches or drips onto another food, or when bacteria on your hands, work surfaces, equipment or utensils are spread to food. Home Illnesses and conditions Infections and poisoning Food poisoning. Food poisoning See all parts of this guide Hide guide parts 1.

About food poisoning 2. Causes of food poisoning 3. Treating food poisoning 4. Preventing food poisoning. About food poisoning Food poisoning is an illness caused by eating contaminated food.

Signs and symptoms The symptoms of food poisoning usually begin within one to two days of eating contaminated food, although they may start at any point between a few hours and several weeks later.

The main symptoms include: feeling sick nausea vomiting diarrhoea , which may contain blood or mucus stomach cramps and abdominal pain a lack of energy and weakness loss of appetite a high temperature fever aching muscles chills In most cases, these symptoms will pass in a few days and you will make a full recovery.

What to do Most people with food poisoning recover at home and don't need any specific treatment, although there are some situations where you should see your GP for advice see below. Read more about treating food poisoning When to see your GP You should contact your GP if: your symptoms are severe — for example, if you're unable to keep down any fluids because you are vomiting repeatedly your symptoms don't start to improve after a few days you have symptoms of severe dehydration , such as confusion, a rapid heartbeat, sunken eyes and passing little or no urine you're pregnant you're over 60 your baby or young child has suspected food poisoning you have a long-term underlying condition, such as inflammatory bowel disease IBD , heart valve disease, diabetes or kidney disease you have a weak immune system — for example, because of medication, cancer treatment or HIV In these situations, your GP may send off a stool sample for analysis and prescribe antibiotics , or they may refer you to hospital so you can be looked after more closely.

How is food contaminated? Causes of food poisoning Food can become contaminated at any stage during its production, processing or cooking. For example, it can become contaminated by: not cooking food thoroughly particularly meat not correctly storing food that needs to be chilled at below 5C keeping cooked food unrefrigerated for a long period eating food that has been touched by someone who is ill or has been in contact with someone with diarrhoea and vomiting cross-contamination where harmful bacteria are spread between food, surfaces and equipment Cross-contamination can occur, for example, if you prepare raw chicken on a chopping board and don't wash the board before preparing food that won't be cooked such as salad , as the harmful bacteria can be spread from the chopping board to the salad.

See preventing food poisoning for information about reducing these risks Types of infection Food contamination is usually caused by bacteria, but it can also sometimes be caused by viruses or parasites. Campylobacter In the UK, campylobacter bacteria are the most common cause of food poisoning. Salmonella Salmonella bacteria are often found in raw or undercooked meat, raw eggs, milk, and other dairy products.

Escherichia coli E. Shigella Shigella bacteria can contaminate any food that has been washed in contaminated water. Viruses The virus that most commonly causes diarrhoea and vomiting is the norovirus.

Parasites In the UK, food poisoning caused by parasites is rare. Parasitic infections that can be spread in contaminated food include: giardiasis — an infection caused by a parasite called Giardia intestinalis cryptosporidiosis — an infection caused by a parasite called Cryptosporidium ameobiasis — a type of dysentery caused by a single-cell parasite ameoba called Entamoeba histolytica this is very rare in the UK The symptoms of food poisoning caused by a parasite usually develop within 10 days of eating contaminated food, although sometimes it may be weeks before you feel unwell.

Treating food poisoning Food poisoning can usually be treated at home without seeking medical advice. You should also: rest as much as possible eat when you feel up to it — sticking to small, light and non-fatty meals at first bland foods such as toast, crackers, rice and bananas are good choices avoid alcohol, caffeine, fizzy drinks and spicy and fatty foods because they may make you feel worse Contact your GP if your symptoms are severe or don't start to improve in a few days.

Preventing the spread of infection If you have food poisoning, you shouldn't prepare food for other people and you should try to keep contact with vulnerable people, such as the elderly or very young, to a minimum. Stay off work or school until at least 48 hours after the last episode of diarrhoea. If someone you live with has food poisoning, you should: make sure everyone in your household including yourself washes their hands with soap and warm water regularly — particularly after going to the toilet and before and after preparing food clean surfaces, toilet seats, flush handles, basins and taps frequently make sure everyone has their own towels and flannels wash the laundry of the infected person on the hottest washing machine setting Oral rehydration solution ORS Oral rehydration solutions ORS are recommended for people vulnerable to the effects of dehydration, such as the elderly and those with a pre-existing health condition.

Further treatment If your symptoms are severe or persistent, or you are more vulnerable to serious infection for example, because you are elderly or have an underlying health condition , you may need further treatment. Preventing food poisoning The best way to avoid getting food poisoning is to ensure you maintain high standards of personal and food hygiene when storing, handling and preparing food.

Cleaning You can prevent the spread of harmful bacteria and viruses by maintaining good personal hygiene standards and keeping work surfaces and utensils clean. Regularly wash your hands with soap and warm water, particularly: after going to the toilet or changing a baby's nappy before preparing food after handling raw food after touching bins or pets You shouldn't handle food if you are ill with stomach problems, such as diarrhoea or vomiting or you have any uncovered sores or cuts.

Cooking It's important to cook food thoroughly, particularly meat and most types of seafood, to kill any harmful bacteria that may be present. Chilling Certain foods need to be kept at the correct temperature to prevent harmful bacteria from growing and multiplying.

If food has to be refrigerated, make sure your fridge is set to 0—5C 32—41F. Cross-contamination Cross-contamination is when bacteria are transferred from foods usually raw foods to other foods. To prevent cross-contamination: always wash your hands after handling raw food store raw and ready-to-eat foods separately store raw meat in sealable containers at the bottom of your fridge so that it cannot drip onto other foods use a different chopping board for raw food and ready-to-eat food, or wash it thoroughly in between preparing different types of food clean knives and other utensils thoroughly after using them with raw food do not wash raw meat or poultry — any harmful bacteria will be killed by thorough cooking, and washing may splash harmful bacteria around the kitchen.

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