There are more than 2,000 strains in the salmonella group of bacteria. It is found in poultry and other animal-derived foods, eggs and unpasteurised milk. The most common forms include salmonella enteritidis and salmonella typhimurium. The latter type has been identified in products taken from Midland Meats, the Dundrum butcher shop at the centre of the latest outbreak.
A recent medical conference held in Dublin was told that increased dependence on convenience foods with fewer preservatives and intensive farming methods were contributing to a rapid increase in food-borne illness.
There have been a number of salmonella outbreaks in Ireland in recent years, including a case in Mayo General Hospital in January last year which affected 21 people.
A survey conducted last year by the Consumer Association of Ireland found that grocery retailers frequently engage in high-risk practices in the storage and presentation of chilled foods. Failures in handling and temperature control of such foods were most evident among independent food outlets.
This coincided with consumers eating unprecedented amounts of chilled produce. Of 73 retailers surveyed in April 1997, only 10 per cent of independent outlets monitored the temperature of chilled foods at the point of receipt; 52 per cent during storage; and 79 per cent during display.
It found that personal hygiene standards had improved over the past decade, but considerable improvement needed to be made in independent outlets. Where there is a failure to wear disposable gloves when handling chilled foods, hand-washing is critical in avoiding cross-contamination.
Symptoms of salmonella
Symptoms usually develop suddenly about 12 to 72 hours after infection. Symptoms include feeling generally unwell, headache, abdominal pain, diarrhoea, and occasionally shivering and fever. In most cases symptoms last only two or three days. Dehydration or septicaemia may occur in the young or the elderly. It can be treated with antibiotics.