Background: CDC's healthcare-associated infection (HAI) surveillance system, the National Healthcare Safety Network (NHSN), focuses on device- and procedure-associated infections in select hospital locations rather than all HAIs occurring hospital-wide. HAI point prevalence surveys may complement existing data by addressing all HAI types across all patient populations in a resource-effective way to inform local or national policy.
Objective: To determine HAI prevalence in a pilot study of 9 acute-care facilities in Jacksonville, FL, and evaluate the performance of proxy indicators for HAIs.
Methods: HAIs were defined using NHSN criteria. In each facility a trained Primary Team (PT) of infection prevention (IP) staff performed the survey on 1 day, reviewing records and collecting data on a random sample of inpatients. Data included: demographics, risk factors and proxy HAI indicators (leukocytosis/leukopenia, antimicrobial therapy, and temperature). PTs assessed patients with ≥1 proxy indicator for HAIs. An Evaluation Team (ET) of external IP experts collected data from a subset of patient records reviewed by PTs to assess proxy indicator performance and validate PT data collection. All patients in this subset were assessed for the presence of HAIs. PT data were used to calculate HAI prevalence (total no. of HAIs divided by the total no. of surveyed patients). ET data were used to calculate proxy indicator sensitivity, specificity, positive and negative predictive values (PPV, NPV).
Results: PTs identified 58 HAIs among 855 patients, for a prevalence of 6.8%. Surgical site infections (n=18), urinary tract infections (n=9; 56% catheter-associated), pneumonia (n=9; 22% ventilator-associated), and bloodstream infections (n=8; 100% central line-associated) accounted for >75% of all HAIs. Other HAIs included infections of the gastrointestinal tract (n=4); skin and soft tissue (n=4); lower respiratory tract (n=2); eye, ear, nose, throat, or mouth (n=2); cardiovascular system (n=1); and central nervous system (n=1). Antimicrobial therapy was the most sensitive proxy indicator (Table).
Conclusions: HAI prevalence in this single-city pilot was similar to that reported from CDC's 1970s Study on the Efficacy of Nosocomial Infection Control (SENIC) and to 2002 HAI prevalence estimates derived from National Nosocomial Infections Surveillance system data. Use of antimicrobial therapy to determine which patients need detailed medical record review for the presence of HAIs may reduce data collection burden and improve survey efficiency. Additional work is needed on validation and feasibility to extend methodology to a national scale.
Table: Proxy indicator performance in identifying patients with HAIs.
Indicator
| Sens. (%)
| Spec. (%)
| PPV (%)
| NPV (%)
|
Leukocytosis or leukopenia
| 52.4
| 73.4
| 12.1
| 95.5
|
Antimicrobial therapy
| 95.5
| 62.9
| 14.4
| 99.5
|
Temperature >38°C (all ages) or <36°C (infants ≤1 year)
| 13.6
| 93.1
| 11.5
| 94.3
|