Food Poisoning

What causes food poisoning?

Raw produce or food that is not properly cooked can cause foodborne illness.  These foods can be contaminated with bacteria and viruses (Norovirus, Campylobacter, Salmonella, Staphylococcus or E. coli), parasites (Toxoplasma gondii), mould, or contain toxins (pesticides, mushroom toxin).

In 2011 the Food Standards Agency estimated that each year in the UK around a million people suffer a foodborne illness, resulting in around 500 deaths.

How do I get food poisoning?

Food poisoning may occur from consuming:
  • Raw fish or oysters
  • Undercooked meat or eggs
  • Any food prepared using utensils, chopping boards and other tools that are not fully cleaned
  • Water from a well or stream, or city or town water that has not been treated
  • Dairy products or food containing mayonnaise (eg, coleslaw or potato salad) that have been out of the fridge for too long

What are the symptoms of food poisoning?

Symptoms of food poisoning range from diarrhoea to long-term health problems or even death. Common symptoms include nausea and vomiting, dehydration, watery, non-bloody diarrhoea, fever, upset stomach and abdominal cramps. In most cases, symptoms go away on their own within two to three days. Contact your GP if the following occurs as your infection may be serious:

  • Diarrhoea along with high fever (>39°C)
  • Blood in the stool
  • Unable to rehydrate because of persistent vomiting
  • Signs of dehydration (decrease in urination, dry mouth and feeling dizzy when standing up, or having diarrhoea for more than three days)

How is food poisoning treated?

  • Self-care: in most cases food poisoning will go away after a few days. It is important to ensure adequate fluid and electrolyte balance by drinking more water and replenishing electrolytes.  Oral rehydration solutions such as Dioralyte® and Electrolade® are available to buy over the counter. Diluted fruit juice, soft drinks and soups are also alternatives.
  • If you have diarrhoea and are unable to keep down fluids, you may need to be given fluids through a vein (intravenously)
  • Most people fully recover from the most common types of food poisoning within 12 to 48 hours
  • If symptoms get worse or persist for more than seven days consult your GP as you may need antibiotic treatment

What are some preventative measures I can take?

Preventative steps can be taken to reduce the risk of food being contaminated with germs:

  • Clean up spills immediately and wash hands with warm soapy water
  • Separate raw mear, fish and poultry from other food such as fruits and vegetables that will not be cooked
  • Cook food to a safe minimum temperature
  • Chill all food in the fridge or freezer accordingly. Don't leave meat, fish, poultry or cooked food sitting for more than two hours at room temperature.

Other precautions you may take are:

  • Always check the "Sell-By" date (you should buy the product before the date expires)  and "Use-By" date (the last date recommended for the use of the product) of your food purchases
  • When travelling, keep cold food at about 4°C or below by placing food in a cool-box or cool-bag with ice or frozen gel packs.
  • When eating out, ask if the food contains any uncooked ingredients and also ask how the food has been cooked.

Further information:

Food Standards Agency
Aviation House
125 Kingsway
London WC2B 6NH
Tel: 020 7276 8829

Fact sheet provided by MIMS

Date last reviewed: November 2014

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