There is increasing interest concerning the possible impact of anti-tumour necrosis factor (TNF)-alpha therapeutic agents on the emergence of infections. However, these agents do not seem to increase the incidence of adverse infectious events significantly. Published observations concern mostly infections of the urinary and upper respiratory tracts that develop in the setting of co-morbidities, such as anterior or concomitant immunosuppressive treatment. Infliximab appears to increase the risk of tuberculosis, but this effect has not been observed with other anti-TNF-alpha agents. To better characterise the adverse infectious effects associated with these agents, physicians should be encouraged to notify the microbiological data relating to all cases.