Respiratory viruses in patients and employees in an intensive care unit

Stupica, D.; Lusa, L.; Petrovec, M.; Žigon, N.; Jevšnik, M.; Bogovič, P.; Strle, F.

PURPOSE: To evaluate the frequency of respiratory viruses in a nonselected population of intensive care unit patients and employees and to investigate the clinical as well as the epidemiological association with virological findings. METHODS: Between 12 January and 5 March 2009, nasopharyngeal swabs were collected from 55 intensive care unit (ICU) patients and 41 medical personnel at 16 different time-points and tested for 11 respiratory viruses by single real-time PCR using TaqMan or MGB probes. RESULTS: Among the 55 ICU patients tested, there were 30 virus-positive respiratory specimens (30/173, 17.3%) and 23 patients who tested positive at least once for respiratory viruses (23/55, 41.8%). Only the time from admission to the ICU was associated with the probability of testing positive, with the probability of testing positive decreasing with increasing length of stay (P < 0.001). Of the 418 respiratory specimens collected from the healthcare personnel, 27 (6.5%) tested positive. Seventeen employees tested positive at least once for respiratory viruses (17/41, 41.5%). Among the employees, calendar time (P = 0.03) and having sick contacts at home (P = 0.006) were significantly associated with swab positivity. Among the study population, patients had a significantly higher probability of having a positive swab result than employees. The distribution of viruses differed between the two groups. CONCLUSIONS: Our results suggest that when hygiene precautions are adopted, the possibility of transmitting selected respiratory viruses between patients and personnel is limited. They also point to a greater importance of the community over the hospital environment for acquisition of viral respiratory infections by ICU patients and employees. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s15010-012-0245-6) contains supplementary material, which is available to authorized users.