Microbes and food 5. Food poisoners
Year number of cases
1996 94,923
1997 105,579
1998 105,060
1999 96,866
2000 98,076
2001 85,752
2002 81,562
Table 5.1: Food poisoning incidents reported in England and Wales 1996 – 2002.
Source: Health Protection Agency.
5.1 Food poisoning
There are at least a million cases of microbial food poisoning in the UK each year - though the vast majority go unreported. Most people suffer from a foodborne illness at some time in their lives. The symptoms of vomiting, diarrhoea, abdominal pain and fever are thoroughly unpleasant. But the estimated costs of medical care and lost working time are also worrying - at about £1 billion a year.

How can anything as small as microbes cause all this trouble? Food poisoning organisms present a hidden danger in our food, but it is possible to defeat them. Most food-borne illness is preventable.

What is food poisoning?

Food poisoning is any illness brought on by eating contaminated food. It is caused by pathogenic microbes or (rarely) chemicals.

Symptoms vary according to the type of microbe involved and some factors are characteristic to each disease:

  • infective dose – the disease can be triggered by a few cells or may require millions of cells
  • incubation time – the time between infection and symptoms could be hours or weeks
  • duration of illness – can last for hours or months
  • cause of the symptoms – toxins in the food and/or infection.
Picture 5.1a Was it something he ate?
Who's at risk?
The severity of the illness can vary. Most at risk are people who are:Some food poisoning can be fatal.
Food poisoning microbes
The main food poisoning microbes are: