Food Poisoning and Infectious Disease

The symptoms of food poisoning vary depending on what type you have. The time taken for symptoms to start after eating the affected food (incubation period) can vary from a few hours to up to 15 days later! Hence it is important to realise that the last meal you ate may not necessarily be the cause of your symptoms/illness.

Common symptoms include sickness, diarrhoea, stomach cramps and fever. In some people, usually the very young or old, or those who are already ill, food poisoning can cause serious illness.

The main causes of food poisoning are:

• Not cooking food thoroughly
• Storing food incorrectly i.e. out with the fridge, so bacteria can grow
• Cross contamination of ready-to eat foods including foods after cooking
• Infection from food handlers due to poor hygiene practice.
• Preparing food too far in advance
• Not defrosting food correctly

It is important to remember that not all food poisoning is caused by eating out; it can happen at home too.

Whilst different types of germs and foodstuffs are associated with different types of illnesses, by following some simple rules you can help yourself and your family avoid food poisoning as follows:

• Always store raw meat and poultry in a covered container at the bottom of the fridge so that it cannot drip onto other foods.
• Ensure that your fridge is clean and operating between 0 and 5 degrees centigrade
• Always defrost meat, fish and poultry thoroughly before cooking.
• Cook food thoroughly and if reheating, ensure it is piping hot all the way through before eating.
• If hot food is not to be eaten immediately, cool it quickly (within 90 minutes) and place it in your refrigerator.
• Ensure that work surfaces, cloths, utensils and chopping boards are cleaned thoroughly (between use) especially after being used for raw meat, poultry or fish.
• Always wash fruit and salad before eating it.
• Avoid making dishes with raw eggs eg mayonnaise, mousse, which do not get a thorough cooking
• Always wash your hands with soap and hot/warm water before preparing food and after handling raw foods eg meat, poultry, eggs etc, after going to the toilet, after playing with pets, after changing nappies, caring for people suffering from diarrhoea or vomiting, handling laundry, etc.
• Keep any cuts/wounds covered with a waterproof dressing when preparing food.
• Keep dogs, cats, etc. out of the kitchen when preparing food and always wash their bowls separately to dishes etc.
• Never drink untreated water from outdoor sources eg lakes or streams/burns etc

Some illnesses are not necessarily caused by bacteria growing on food. Parasites such as Giardia or Cryptosporidium, which live in the intestines of humans and animals, can cause infection through contact with farm or other animals or their faecal material, by drinking untreated / contaminated water, or eating contaminated food.

Furthermore viruses are a common cause of illness/infection which often present the same symptoms i.e. vomiting and/or diarrhoea, as food poisoning. Spread of this type of infection can be quick and easy and is often from person to person, but can also occur via aerosols or environmental contamination. The symptoms of a viral illness are often characterised by their swift onset and self-limiting nature , generally lasting no more than 24 to 72 hours.

If you think you have food poisoning you should:

• Visit your doctor/GP as soon as possible in order to submit a stool/faecal sample for examination.
• Wash your hands frequently especially after using the toilet and before handling food
• Ensure you practice good personal hygiene

If you suspect food consumed from a food premises in Dundee may be the cause of your illness, contact us.

You MUST tell your supervisor/manager/employer. At the very least you should not return to your work until you have been symptom-free for 48 hours. There are specific circumstances in which you may be formally excluded from your work.

It is strongly recommended that children aged under 5 years and those unable to implement good standards of personal hygiene (i.e. hand washing after being at the toilet), be kept away from pre-school, school or other such establishments until they have been symptom-free for 48 hours to avoid the spread of any infection.

The Food Safety team work closely with NHS Tayside Health Protection Team in the investigation of notified/confirmed cases of food poisoning and act to control outbreaks of food and waterborne infections throughout Dundee. Such cases are usually reported to this Department by the Health Protection Team following receipt of positive results from the microbiology laboratory. This normally arises from people visiting their GP and submitting a faecal sample for examination.