Incidence of healthcare-associated infections in a tertiary care hospital: results from a three-year period of electronic surveillance

Background: Point prevalence surveillance is widely used to monitor healthcare-associated infections (HAIs). Incidence surveillance offers more accurate information than point prevalence surveillance, but is more time consuming. Electronic surveillance systems may allow for more widespread incidence surveillance. Aim: To determine the incidence of HAI in a tertiary care hospital in Finland over a three-year period from 2011 to 2013 using an automated electronic IS programme, linked to all of the hospital's electronic databases. Methods: The programme identified cases of HAI prospectively from initiation of antibiotic treatment. All of the cases were verified manually after discharge. In order to evaluate the sensitivity of the electronic method for the identification of surgical site infections, the medical records of all patients who underwent cardiac surgery or total joint arthroplasty were evaluated retrospectively. Findings: In total, 78,211 patients, covering 321,974 patient-days, were admitted to the wards during the study period, and 29,694 antibiotic treatment initiations were registered. After manual review, 5089 (17.1%) of these were found to be for HAIs. The total time needed to undertake the surveillance for the whole hospital (353 hospital beds) was 255 days, which is the approximate total annual working time for one nurse. Sensitivity evaluation showed that the number of surgical site infections identified by manual and electronic methods was identical. The three-year incidence of HAI was 15.8 per 1000 patient-days and 4.9% of all discharged patients. Conclusions: Continuous electronic incidence surveillance based on initiation of antibiotic treatment may be a practical means of measuring hospital-wide incidence of HAI, but this method still requires personnel resources. (C) 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.