Economics of nosocomial MRSA infection in Europe: Measuring the direct costs of infection, with an economic evaluation of rapid screening on admission to hospital surgical wards

Healthcare associated infections (HAIs) have substantial effects on individual patients and hospitals. In particular, methicilin-resistant staphylococcus aureus (MRSA) has become an important bacterial pathogen worldwide, exacerbating the overall burden of nosocomial infection. Hospital decision-makers face significant challenges when attempting to reduce MRSA infection. Additional evidence is necessary regarding cost-related outcomes of infection, cost-effectiveness of infection control interventions, and local infection control decision-making among hospital staff.;A retrospective analysis was performed relying on data from MRSA infected and MRSA colonized patients involved in a large interventional study conducted between 2004 and 2006. Multivariate estimation was used to control for endogeneity as a result of the identification of an exogenous instrumental variable. Cost and resource utilization data were used to construct a decision-analysis to estimate the cost-effectiveness of rapid MRSA screening. Finally, the grounded theory and constant comparison qualitative research frameworks were used to analyze semi-structured interviews conducted with infection control practitioners in Switzerland, Spain, France, Italy, UK, Serbia, The Netherlands, and Israel.;The mean LoS of MRSA-infected surgical patients was 61 days compared to 21 days for MRSA carriers (P<0.001). Excess LoS attributable to MRSA from the multivariate analysis was 13 days (P<0.001, 95% C.I. 11--15 days). The excess LoS attributable to MRSA based on the instrumental variables analysis fell to 4.6 days, however the MRSA coefficient lost significance in the second stage (P>0.5). The incremental cost-effectiveness of universal rapid PCR among surgical patients was estimated to be CHF 18,155 per infection avoided when using the excess LoS estimate of 13 days. Important factors influencing the results include the cost of each MRSA infection (linked to the attributable LoS), the prevalence of MRSA on admission, and the turnaround-time of test results. Based on the semi-structured interviews with senior infection control practitioners, critical success factors for the control of MRSA infection include: (a) a formally-structured infection control unit that cuts across hospital departments; (b) direct access to department heads and hospital managers to share information and make investment requests; (c) ward staff buy-in to interventions selected for implementation; and (d) robust measurement systems, including surveillance and reporting of MRSA cases.;MRSA results in an important economic burden by significantly prolonging LoS. However, there is significant risk that published estimates are upwardly biased due to confounding and endogeneity. The cost-effectiveness of rapid PCR screening---an intervention debated in the current literature---is strongly influenced by the estimate of MRSA infection cost (derived from excess LoS attributable to infection) as well as local epidemiological factors. Finally, while improved methodologies may yield less biased estimates, the translation of economic evidence into actual infection control practice appears limited.