Eradication of multi-resistant Salmonella typhimurium DT104 infections in 15 Danish swine herds

Multi-resistant Salmonella typhimurium DTI 04 (=DTI 04) was first isolated in United Kingdom in the 1980s. DT104 was isolated in Denmark for the first time in 1996 (1). Retrospective analysis of isolates detected DTI 04 in a Danish swine herd in 1991. The majority of the Danish isolates are characterized by being resistant to 5 frequently used antibiotics; ampicillin, chloramphenicol, streptomycin, sulphonamides and tetracycline (ACStSuT), but isolates being resistant to e.g. flouroquinolones as well have been detected. DTI 04 is now known as an important and emerging pathogen in many countries (2, 3, 4, 5). DTI 04 has spread rapidly between animals within the herd, between herds and to other species (6). Salmonella \u27JYphimurium DTl 04 remains the second most common Salmonella in humans in England and Wales in 1997,95 pet. of the isolates were resistant to four or more antibiotics with the most common resistance pattern is that of ACStSuT (7). The described combination of the ability to spread rapidly and the multiresistance towards antibiotics used frequently in animals and humans implies that DTI 04 can be a serious problem for both animals and humans. By June 1999 DTI04has been detected in 16 swine herds, 12 combined swine and cattle herds and 2 cattle herds in Denmark. HumaneDTI04 cases have slightly increased in Denmark from 1997 to 1998. DTI04 now accounts for 13 pet. of Salmonella typhimurium phage types compared to 7 pet. in 1997. This increase is explained by the first community outbreak of DTI 04 in Denmark