Salmonella in rodents: a risk to man?

Studies of salmonella infections in rodents in the United Kingdom have focused particularly on rats and house mice. Only rarely were more than 10% of animals found to carry salmonella. The organisms were mostly cultured from spleen or liver and less than 3% of animals were found to carry these organisms in the intestine. The extensive use of 'virus' rodenticides (consisting of salmonella cultures) in the first half of this century increased the prevalence of salmonella carriage in rodents and was a hazard to human health. Whilst rodents certainly acted as sources of human salmonella infection in the UK in the past, their role has probably never been great.