08.12.2012

O’Brien, University of Liverpool Institute of Infection and Global Health (2012)

Remarkable changes in the epidemiology of human non‐typhoidal salmonellosis have occurred in the UK over the last century. Between 1981 and 1991, the incidence of non‐typhoidal salmonellosis in the UK rose by more than 170%, driven primarily by an epidemic of Salmonella enterica subsp. Enteritidis phage type (PT) 4, which peaked in 1993. Measures introduced to control this epidemic included legislation, food safety advice and an industry‐led vaccination programme in broiler breeder and laying poultry flocks. The incidence of S. Enteritidis has been falling since 1997 and levels of S. Enteritidis PT4 have fallen to pre‐epidemic levels and have stayed low. When salmonella peaked in 1993 in the UK, more than 18,000 laboratory-confirmed cases of illness were recorded in national surveillance statistics, yet by 2010 this had fallen to just 459. The temporal relationship between vaccination programmes and the reduction in human disease is compelling and suggests that these programmes have made a major contribution to improving public health.