SALMONELLA VIRCHOW PT-26 INFECTION IN ENGLAND AND WALES - A CASE-CONTROL STUDY INVESTIGATING AN INCREASE IN CASES DURING 1994

An increase in the number of human isolates of Salmonella virchow phag e type (PT) 26 in England and Wales during 1994 was investigated. A na tional case control study was conducted which included 88 cases and 18 2 controls. The cases were mostly young adults (median age 26) and 13 (15%) were admitted to hospital. Acquisition of S. virchow PT 26 was a ssociated with the consumption of any chicken (OR 2.5, CI 1.1-5.8), of chicken curry from restaurants and take aways (OR 2.9, CI 1.4-6.1), a nd of some other diverse types of pre-prepared chicken (OR 3.8, CI 1.9 -7.6). Halal chicken was associated (P = 0.006) with illness in a subs et. There were negative associations with contact with animals (OR 0.4 7, CI 0.23-0.95) and with the consumption of chicken cooked whole (OR 0.37, CI 0.21-0.66). The increase in S. virchow PT 26 may be due to ch anging epizoology and may be an indicator of what will become the domi nant salmonella strain in poultry in future years. The increasing inci dence of S. virchow PT 26 is of particular concern because of its asso ciation with more invasive disease in humans.