Over the last decade, antibiotic resistance and particularly multiple resistance (to four or more drugs) has increased dramatically in salmonellae isolated from infected patients in Western Europe and North America. An important factor in this increase has been the epidemic spread, since 1990, of multiresistant Salmonella typhimurium definitive phage type (DT) 104 with resistance to ampicillin, chloramphenicol, streptomycin, sulphonamides and tetracyclines (ACSSuT resistance type).1 Strains of this phage type/ resistance type combination have become widely distributed in cattle in the UK since the early 1990s,2 and have subsequently been transmitted to humans through the food chain.3 In England and Wales, isolations of multiresistant DT 104 from humans increased from about 200 in 1990 to >4000 in 1996.4 However, over the last two years there has been a significant decline in isolations, with numbers dropping by 48% in 1998, to 2090.5