How do the salmonella bacteria spread?
Food is the commonest source of salmonella for humans. The food may have been contaminated because the source, animal or bird, was infected. Salmonella is common among chickens, studies in 1990 showing that about 50% of frozen and fresh chicken contain the bacteria. Infections in dairy herds may lead to contamination of milk, which if not adequately pasteurised may be consumed directly or used in the preparation of milk products eg babies’ dried milk feeds and cause infection. Adequate cooking should eradicate salmonella in food. However salmonella may be spread in a kitchen from contaminated to non-contaminated food if hygiene and catering practices are substandard. Food should be stored in refrigerators to prevent the bacteria multiplying at room temperature. Food may also be contaminated by the hands of infected food handlers if they do not wash them properly after going to the toilet. If food prepared for a party or gathering is contaminated an outbreak of salmonella food poisoning
