The relative sensitivity of immediate early nuclear antigen detection (IENAD) and conventional cell culture for human cytomegalovirus (HCMV) and the role of the first test in surveillance for infection remain controversial. If all positive results were considered accurate, IENAD and culture gave similar sensitivities [207/284 (73%) vs. 192/284 (68%)] with urines, heparinised bloods, bronchoalveolar lavage fluids, and other clinical specimens. Nonetheless, IENAD could not replace culture, because only the latter identified 77 (27%) of 284 positive samples. The role of IENAD in surveillance for HCMV infection is discussed in the light of low positivity rates with surveillance specimens.