Enteritis due to Salmonella panama from infected ham.

After the appearance of sporadic cases of enteritis due to Salmonella panama, baked ham from one supplier was implicated as the source of infection. No pathogenic organisms were isolated from the working surfaces of the factory involved or from samples of a day's bacon output, but S. panama was isolated from the factory sewers. Stool examinations of the 500 employees showed one man in the baked ham section to be excreting S. panama. He was removed from work and no further infections were reported from the district. The organism could no longer be found in the sewers.Some weeks later, further infections were reported in the London and Southend areas, which could be traced to ham from the original source. Sewer swabs at the factory were again positive. A further examination of all the employees revealed three cases and 82 symptomless excretors. Eight of 192 family contacts were also found to be excretors. Trimethoprim-sulphamethoxazole appeared to have no effect on the carrier state.Examination of the hams in cold store showed some to be infected with S. panama, and a number of these had been consumed in the canteen.Subsequent examination of pigs at slaughter and pig food prepared locally failed to isolate S. panama. The source of infection at the factory is unknown.