Background: Healthcare-acquired viral acute respiratory infections (ARIs) are a common problem in neonatal care. Health-care workers may transmit viruses to neonates when having a symptomatic or asymptomatic ARI.

Aim: This prospective nine-month repeated point-prevalence cohort study aimed to investigate the occurrence and aetiology of asymptomatic and symptomatic ARIs in health-care employees in a tertiary neonatal intensive care unit (NICU).

Methods: Flocked nasal swabs were collected on every second Tuesday in a NICU from all personnel working on that day. Additionally, in the case of ARI symptoms, a nasal swab was self-collected by the study subjects.

Findings: A virus was detected in 16 (3.3%) of the asymptomatic subjects. Altogether 36 symptomatic ARIs (mean 0.5 per person) were reported.

Conclusion: Our data suggests that ARIs are not uncommon among NICU health-care workers and moreover are commonly asymptomatic. It is noteworthy that these individuals may transmit.