The vast majority of people whose diarrhoea has settled down are not a risk to others and hence repeated testing of their faeces is not necessary. Investigations are carried out by telephone or a visit by Environmental Health officers enquiring on risk factors and offering advice on hygiene and the prevention of future infection. For the majority of patients with a salmonella infection, antibiotic treatment is not required. The inappropriate use of some antibiotics may encourage and prolong the carrier state. However, antibiotics may be beneficial for some patients, such as those with a severe systemic illness, the elderly and very young, or those with a damaged immune system.
Food is the commonest source of salmonella for humans.
The food may have been contaminated because the source, animal or bird, was infected. 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.