The step from a voluntary to a mandatory national nosocomial infection surveillance system: the influence on infection rates and surveillance effect

In order to compare voluntary and mandatory surveillance data, two groups were defined by the surveillance start date. Neonatal intensive care unit (NICU) parameters and infection rates of the NICUs in both groups were compared. In order to analyze the surveillance effect on primary bloodstream infection rates (BSI), all VLBW infants within the first three years of participation in both groups were considered. The adjusted effect measures for the year of participation were calculated.An increase from 49 NICUs participating in 2005 to 152 in 2006 was observed after the introduction of mandatory participation. A total of 4280 VLBW infants was included in this analysis. Healthcare-associated incidence densities rates were similar in both groups. Using multivariate analysis with the endpoint primary BSI rate and comparing the first and third year of participation lead to an adjusted incidence rate ratio (IRR) of 0.78 (CI95 0.66-0.93) for old (voluntary) and 0.81 (CI95 0.68-0.97) for new (mandatory) participants.The step from a voluntary to a mandatory HCAI surveillance system alone may lead to substantial improvements on a countrywide scale.