Phage Types of Salmonella enterica ssp. enterica serovar Typhimurium Isolated from Production Animals and Humans i Denmark

Abstract

S. Typhimurium is one of the 2 most common salmonella serotypes causing human salmonellosis in Denmark. In order to illustrate the significance of different production animals as a source of infection, 1461 isolates were characterized by phage typing. The isolates originated from human patients and from cattle, pigs and poultry. By phage typing the isolates could be separated in 35 different phage types. Five types (10, 12, 66, 110 and 135) predominated and comprised 78.8% of the isolates. In humans, 57.3% of the isolates were phage type 12. This phage type was also predominant in pig herds and, to a lesser degree, in cattle. Phage types 110, 120, 135 and 193 constituted 86.5% of the poultry isolates while these phage types only made up 12.9% of the human isolates. The investigation showed that pigs are probably a major source of S. Typhimurium infection in humans in Denmark today.

Sammendrag

S. Typhimurium er den ene af de to hyppigste årsager til human salmonellose i Danmark. Med henblik på at belyse betydningen af forskellige produktionsdyrs betydning som smittekilde er 1461 isolater blevet karakteriseret ved fagtypning. Isolater fra kvæg, svin og fjerkræ er sammenlignet med isolater fra mennesker. Fagtypning kunne inddele det samlede materiale i 35 typer, hvoraf 5 typer (10, 12, 66, 110 og 135) alene udgjorde 78,8%. Blandt humane isolater tilhørte 57,3% fagtype 12. Denne fag-type var også dominerende blandt isolater fra svin og i mindre udstrækning blandt isolater fra kvæg. Fagtyperne 110, 120, 135 og 193 udgjorde 86,5% af fjerkræisolaterne, men disse fagtyper udgjorde kun 12,9% af de humane isolater. Undersøgelsen antyder, at svin i dag udgør en væsentlig kilde til human salmonellose forårsaget af S. Typhimurium i Danmark.