Infections brought on by any of the salmonella group of bacteria. One type of salmonella causes typhoid fever; another causes paratyphoid fever, others commonly result in bacterial food poisoning. Elderly people, infants, and those who are debilitated are the most susceptible.
In most cases, the source of salmonella poisoning has been traced to poultry products and especially to chicken meat and hen’s eggs. The infection of eggs can originate in the hen’s ovaries or can arise as a result of faecal contamination via the eggshell.
Symptoms of salmonella food poisoning often appear suddenly 12-24 hours after infection and include headache, abdominal pain, nausea, diarrhoea and occasionally fever. They often last for only two or three days, but in extreme cases dehydration or septicaemia (blood poisoning) can develop particularly in the very young and old.
Treatment is by rehydration therapy to replace lost fluids. In extreme cases, fluid can need to be replaced by means of intravenous infusion and antibiotic drugs can be needed.
In general it is advisable to avoid foods that contain raw egg (such as homemade mayonnaise). The risk of infection is reduced in very fresh eggs. Salmonella bacteria are not killed by light cooking, and eggs given to the frail or elderly or children should be cooked through.