British public-health investigators are tracking the source of a Salmonella outbreak which has put nine people in the hospital and sickened 57. Those who became ill range in age from an infant to an 87-year-old. The U.K. government’s Food Standards Agency reported Thursday that cooked ham from small independent butchers may be the source of the outbreak, with 30 cases so far confirmed in England since the end of August and another 21 in Wales. Tests revealed that the culprit is Salmonella Typhimurium, officials said. One supplier was identified as a potential source; however, no trace of Salmonella has apparently been found in that company’s products. Investigators did identify some hygiene issues among the inspected suppliers, which resulted in one voluntarily recalling some batches of cooked ham. Salmonella infection is typically caused by eating contaminated raw or undercooked foods such as meat, eggs and dairy products. Symptoms usually include diarrhea, stomach cramps, vomiting and fever. This current outbreak is the largest public-health scare the U.K. has experienced since June 2006 when Cadbury voluntarily recalled more than a million chocolate bars after Salmonella was found in some samples. A leaking pipe at a production facility was later identified as the source of the problem.