Is cohorting the only solution to control carbapenemase-producing Enterobacteriaceae outbreaks? A single-centre...

Carbapenemase-producing Enterobacteriaceae (CPE) are a major health issue. Cohorting may help to control spread of CPEs in hospitals, but is expensive and hard to implement.

To identify ward variables associated with CPE in-hospital transmission in a hospital where cohorting has never been implemented.

Cohort prospective study, comparing 14-consecutive-day periods regarding in-hospital transmission. Each period met the two following conditions: (i) CPE carriers/infected admitted for ≥48 h; (ii) 80% of relative contact patients were screened at least twice. Periods (a) with no acquired CPE case among relative contact patients were compared to periods (b) during which one or more CPE case acquisition was identified. Variables potentially associated with CPE transmission were assessed: colonization pressure, caregiver:patient ratio, hand hygiene compliance, hydro-alcoholic product consumption, antibiotic consumption, and infection control team (ICT) involvement on the ward.

Sixty-eight periods of two consecutive weeks were included, 18 (26.5%) included at least one CPE case acquisition. By multivariate analysis, colonization pressure (odds ratio: 1.12; 95% confidence interval: 1.0-1.25; P = 0.042) and antibiotic consumption (2.41; 1.02-5.66; P = 0.044) were associated with CPE in-hospital transmission. Caregiver:patient ratio potentiated both these variables, suggesting a role for understaffing in CPE transmission.

Understanding ward variables associated with CPE spread can help design suitable solutions. Colonization pressure and antibiotic consumption seems to be driving in-hospital transmission, along with caregiver:patient ratio. In presence of high colonization pressure, dedicated healthcare workers for managing CPE patients should be implemented. Co-ordination between ICT and antimicrobial stewardship team is also crucial to prevent CPE spread.