International trends in salmonella serotypes 1998-2003--a surveillance report from the Enter-net international surveillance network.

One of the objectives of any surveillance activity is to monitor trends in infections. The international surveillance network for human enteric infections, Enter-net, has been collecting and reporting data on laboratory-confirmed human salmonella infections since 1993. The number of cases identified rose in the mid-1990s, with the peak being in 1997. This paper describes the subsequent decline in salmonella serotypes being reported by the national reference laboratories participating in the Enter-net surveillance network between 1998-2003. The total number of human cases of salmonellosis reported by the Enter-net participating countries has fallen from 22,698 to 142,891 during this period. Even at these reported levels salmonellosis remains a major cause of morbidity in humans.