BACKGROUND: Tuberculosis (TB) incidence has increased in England and Wales since 1987, with much of the increase in migrants from high TB incidence countries. The National Health Service increasingly depends on healthcare workers (HCWs) trained abroad, often from areas of high TB incidence. A retrospective survey of TB incidents in hospital-based HCWs was carried out to describe their frequency, distribution and characteristics. METHODS: Reports of HCWs with TB in hospitals were identified among routine surveillance of TB incidents. Additional data on these and reports of further incidents fitting the study definition were obtained by contacting local and regional Health Protection Units. RESULTS: At least 105 incidents of TB in hospital-based HCWs occurred in England and Wales in 2005. Most involved HCWs from high incidence countries, and most cases had pre-employment occupational health screening. We found no evidence of onward transmission within hospitals. CONCLUSIONS: Pre-employment screening for active disease may not be enough to prevent the occurrence of these incidents. A high index of suspicion among HCWs with TB symptoms is needed. Detection of latent infection with interferon gamma release assays, and the use of preventive treatment, should be evaluated.