Methicillin-Susceptible Strains are of Concern in Neonatal Care Settings

In the context of a methicillin-susceptible Staphylococcus aureus (MSSA) outbreak, Romano-Bertrand, et al. (2014) aimed to improve knowledge of S. aureus (SA) epidemiology in the neonatal care center (NCC) of a tertiary-care teaching hospital.

The researchers performed a complete one-year review of SA carrier, colonized or infected patients. Monthly prevalence and incidence of SA intestinal carriage, colonization and infection were calculated and the types of infection analysed. During the MSSA outbreak, strains were studied for antimicrobial resistance, content of virulence genes and comparative fingerprint in Pulsed-Field Gel Electrophoresis. Hand hygiene and catheter-related practices were assessed by direct observational audits. Environmental investigation was performed in search of a SA reservoir.

Epidemiological analyses showed two or three prevalence peaks on a background of SA endemicity. In the NCC, during 2009, overall MSSA prevalence did not decrease below 5.5%, while mean MRSA prevalence was about 1.53%. Analysis of infection cases revealed that the outbreak corresponded to the emergence of catheter-related infections and was probably related to the relaxation in infection control practices in a context of high colonization pressure. Healthcare workers' white coats appeared as a potential environmental reservoir that could perpetuate SA circulation in the ward.

The researchers say this report emphasizes the importance of integrating MSSA along with methicillin-resistant SA in a program of epidemiological surveillance in the NCC. Their research was published in Antimicrobial Resistance and Infection Control. 

Reference: Romano-Bertrand S, Filleron A, Mesnage R, Lotthé A, Didelot MN, Burgel L, Bilak EJ, Cambonie G and Parer S. Staphylococcus aureus in a neonatal care center: methicillin-susceptible strains should be a main concern. Antimicrobial Resistance and Infection Control 2014, 3:21  doi:10.1186/2047-2994-3-21