Healthcare Antibiotic Resistance Prevalence - DC (HARP-DC); Measuring the Prevalence of vanA Genes in Healthcare Facilities (HCF) in Washington DC

Background: Infection and colonization with vancomycin-resistant Enterococci (VRE) are common in HCFs. Approximately 40% of Enterococcal healthcare-associated infections (HAIs) reported to the National Healthcare Safety Network from DC are resistant to vancomycin; VRE colonization prevalence rates were unknown. Contact Precautions (CP) for VRE, recommended by the Centers for Disease Control and Prevention, are increasingly controversial because of relatively low pathogenicity, growing prevalence, negative effects of isolation, and conflicting evidence about isolation effectiveness.

Methods: The HARP-DC study measured the prevalence of carbapenem-resistant Enterobacteriaceae in DC HCFs; samples were also evaluated for the vanA gene associated with VRE using the Acuitas® MDRO Gene test (OpGen). We assessed 2,216 patients from 16 HCFs (all 8 acute care hospitals (AH); 1 inpatient rehabilitation hospital (IRH), and 7 long term care facilities (LTCF). LTCFs included 5 skilled nursing facilities (SNF) and 2 long term acute care facilities (LTAC)). A total of 1021 patients met inclusion criteria and consented to participate.

Results: Overall VRE point prevalence was 26.4%. Prevalence rates (PR) for AHs, LTCFs, and the IRH were 26.8, 29.5, and 7.7, respectively. The PR for the IRH was significantly lower than other HCFs, and lower than expected, based on the vancomycin resistance rate among HAIs in DC (p <0.01, p<0.01respectively).

Prevalence vanA Prevalence Ratio (PR) and Confidence Interval (CI) Comparing Location Type to Total
Location Type	n HCFs	n patients targeted	n samples	% sampled	n vanA	% vanA	Range % vanA	vanA PR	PR CI
AH	8	1580	725	45.9	194	26.8	0.0-45.6	1.0	0.9-1.2
LTCF	7	543	244	44.8	72	29.5	0.0-74.4	1.2	0.9-1.5
RH	1	93	52	55.9	4	7.7	-	0.3	0.1-0.8 p<0.01
Total	16	2216	1021	46.1	270	26.4	0.0-74.4	-	-

Conclusion: Over a quarter of inpatients in DC HCFs were colonized with VRE, as measured by the prevalence of the vanA gene. DC HCFs may now use these data to evaluate current prevention approaches, including the use of active surveillance and/or CP, and design a collaborative, regional framework for prevention that creates consistency across facilities with individualized implementation based on facility and patient type.