Are community environmental surfaces near hospitals reservoirs for gram-negative nosocomial pathogens?

Background: Hospital visitors and staff visit neighboring businesses, creating the potential for contamination of surfaces with hospital flora.

Methods: Cultures were obtained from environmental surfaces in hospital lobbies and the surrounding community of 6 hospitals in Brooklyn, NY. As a control, cultures were taken from surfaces >1.5 miles from any hospital. Screening for β-lactamases was done by polymerase chain reaction (PCR), and select isolates were fingerprinted by the repetitive extragenic palindromic sequence-PCR method.

Results: Of 493 cultures, most (70%) involved doors from local businesses. Cephalosporin-resistant Citrobacter freundii (n = 3), Escherichia coli (n = 2), and Enterobacter sp (n = 2) were recovered from surfaces near hospitals, but not from control sites. One isolate of Stenotrophomonas maltophilia harbored an integron-associated VIM-2. Acinetobacter baumannii was recovered in 15 samples, including 4.5% of swabs from ≤0.5 miles of the hospitals versus 0% from ≥0.6 miles (P = .004). Eleven A baumannii isolates were clonally related by repetitive extragenic palindromic sequence-PCR and were also related to a known clinical isolate.

Conclusions: Strains of A baumannii and cephalosporin-resistant Enterobacteriaceae can be recovered from environmental surfaces surrounding hospitals. Finding these pathogens in the perihospital environment suggests hand cleansing should be emphasized for all people entering and leaving hospitals. The finding of integron-associated VIM-2 in our region is disconcerting, and further vigilance is warranted.