Impact of an Enhanced Contact Isolation Policy on Rates of Health Care Associated Infections

Background: Health care associated infections are a serious public health problem. In 2004 our hospital implemented an enhanced contact isolation policy (Contact P).

Methods: Using a quasi-experimental design, we compared rates before and after the implementation of Contact P of (1) patient infection or colonization, (2) compliance with hand hygiene policy. We targeted multi-drug resistant Gram negatives (MDRGN), methicillin-resistant Staphylococcus aureus (MRSA), Clostridium difficile (C. diff), and vancomycin resistant enterococcus (VRE).

Contact P mandated use of gowns on entering the room of an infected or a colonized patient. CDC at the time recommended gowns only if ‘substantial' contact was anticipated. Contact P also mandated the use of dedicated medical equipment and cohorting of infected/colonized patients, while CDC recommended these measures ‘when possible.' Rates of infection or colonization were determined from laboratory reports. Relative risks and associated 95% CI's were calculated to assess change in infection rates before and after Contact P implementation. Compliance with hand hygiene policy was determined by anonymous monthly observations.

Results: Rates of infection/ colonization dropped 18% for MDRGN (RR=0.82; 95% CI = 0.75, 0.90), 38% for MRSA (RR = 0.62; 95% CI = 0.52, 0.75), and 36% for C. diff (RR = 0.64; 95% CI = 0.53, 0.78). The rate of VRE infection/colonization did not change significantly (RR = 0.93; 95% CI = 0.77, 1.10). Hand hygiene compliance rates increased from 68% to 79% (p<0.05).

Conclusion: Enhanced contact precautions for MDRGN, MRSA, and C. difficile in a hospital are associated with reduced transmission to patients.