BACKGROUND: Focal outbreaks of sexually transmitted infections (STIs) such as syphilis and gonorrhoea have been reported in the large cities of Western Europe over the past few years. The aim of our study was to determine whether a similar trend is observed in Geneva and the situation with regard to HIV infection. METHODS: We review the incidence of syphilis, gonorrhoea, Chlamydia trachomatis and HIV in Geneva from 1999 to 2004. RESULTS: Figures indicate a steady and sustained increase in the incidence of syphilis, gonorrhoea and Chlamydia trachomatis in Geneva since 1999 that is maintained into 2004. As for HIV, the number of positive testings in Switzerland has stabilised and primary infection figures do not indicate an increase in newly acquired infections in Geneva. CONCLUSION: The situation in Geneva is similar to that observed elsewhere in Western Europe and indicates the need of public health interventions.