Emergence of vancomycin-resistant enterococci in San Francisco Bay area hospitals during 1994 to 1998.

Objective: To determine the magnitude of vancomycin-resistant enterococci (VRE) in three counties in the San Francisco Bay area.

Design: Active laboratory-based surveillance for VRE from January 1995 through December 1996 and a laboratory-based and hospital-based questionnaire survey for 1993 to 1994 and 1997 to 1998.

Setting: All 33 general acute care hospitals in three counties in the San Francisco Bay area.

Participants: Laboratories and infection control professionals serving these hospitals, and staff of the California Emerging Infections Program.

Results: The number of hospitals reporting 1 or more patient clinical VRE isolates was 1 (3%) in 1993, 7 (21%) in 1994, 31 (94%) in 1995, and 33 (100%) in 1996 to 1998. The number of patient isolates increased from 1 in 1993 to 24 in 1994, 176 in 1995, 429 in 1996, 730 in 1997, and 864 in 1998. Most VRE isolates in 1995 and 1996 were from urine and were not associated with serious clinical disease. However, the number of isolates from blood increased from 9 (6% of total) in 1995 to 44 (12% of the total) in 1996, 90 (14%) in 1997, and 100 (13%) in 1998.

Conclusions: Our data document the rapid emergence and increase of VRE in all hospitals in three counties in the San Francisco Bay area during 1994 to 1998. Infection control measures for VRE together with antibiotic utilization programs should be implemented to limit further spread.