873. Clusters of Postpartum Group A Streptococcus (GAS) Infections on a Labor and Delivery (L&D) Unit June-October 2019

Background

GAS can cause severe postpartum infections and may be transmitted from colonized healthcare workers (HCWs).

Methods

Two cases of GAS bacteremia following vaginal delivery were identified on the L&D unit June-July 2019 (Cluster 1), prompting a carrier-disseminator investigation. Two additional cases were identified September-October 2019 (Cluster 2), followed by an additional 3 cases late October 2019, all of whom delivered on the same night (Cluster 3).

All patients and HCWs were evaluated for GAS risk factors and screened for colonization via throat, vaginal and perirectal cultures. During Clusters 1 and 2, only HCWs with patient contact were screened, but this was expanded to the entire unit in October after Cluster 3 was identified. All GAS colonized HCWs were provided chemoprophylaxis and rescreened 7-10 days after treatment to ensure eradication. GAS isolates from patients and HCWs were analyzed by whole genome sequencing (WGS).

Results

During Cluster 1 a total of 43 HCWs were screened and HCWA was colonized at all three sites. In Cluster 2, nine HCWs were screened; HCWA was negative at that time but HCWB was colonized in the throat only. Patient 3 was confirmed to be community acquired by pulsed-field gel electrophoresis, patient 4 was closely related by WGS. A new policy was instituted that required all HCWs present at delivery to wear gowns, gloves, masks, eye protection, and to undergo infection prevention education and practice review. Following Cluster 3, all HCWs on the unit were screened (681 total). HCWA was again positive at all 3 sites and two additional HCWs were found to be colonized with the outbreak strain on throat swab only. Isolates from patients 1, 2, 4, 5, 6, 7 and the 4 HCWs were identified as subtype emm 28 and all closely related by WGS (figure 1). A household contact of HCWA was colonized with the outbreak strain as well.

Figure 1

Conclusion

A carrier-disseminator investigation identified clusters of nosocomial postpartum GAS infections involving 6 patients, 4 HCWs and a HCW household contact that were highly related based on WGS. The outbreak strain of GAS was likely spread amongst HCWs via ping pong transmission on the unit. Transmission to patients was halted with implementation of strict infection prevention measures and mass screening and chemoprophylaxis of all colonized HCWs.

Disclosures

All Authors: No reported disclosures

Novel Visualization of Clostridium difficile Infections in Intensive Care Units

BACKGROUND

Accurate and timely surveillance and diagnosis of healthcare-facility onset Clostridium difficile infection (HO-CDI) is vital to controlling infections within the hospital, but there are limited tools to assist with timely outbreak investigations.

OBJECTIVES

To integrate spatiotemporal factors with HO-CDI cases and develop a map-based dashboard to support infection preventionists (IPs) in performing surveillance and outbreak investigations for HO-CDI.

METHODS

Clinical laboratory results and Admit-Transfer-Discharge data for admitted patients over two years were extracted from the Information Warehouse of a large academic medical center and processed according to Center for Disease Control (CDC) National Healthcare Safety Network (NHSN) definitions to classify Clostridium difficile infection (CDI) cases by onset date. Results were validated against the internal infection surveillance database maintained by IPs in Clinical Epidemiology of this Academic Medical Center (AMC). Hospital floor plans were combined with HO-CDI case data, to create a dashboard of intensive care units. Usability testing was performed with a think-aloud session and a survey.

RESULTS

The simple classification algorithm identified all 265 HO-CDI cases from 1/1/15-11/30/15 with a positive predictive value (PPV) of 96.3%. When applied to data from 2014, the PPV was 94.6% All users "strongly agreed" that the dashboard would be a positive addition to Clinical Epidemiology and would enable them to present Hospital Acquired Infection (HAI) information to others more efficiently.

CONCLUSIONS

The CDI dashboard demonstrates the feasibility of mapping clinical data to hospital patient care units for more efficient surveillance and potential outbreak investigations.

Development and validation of an automated ventilator-associated event electronic surveillance system: A report of a successful implementation

BACKGROUND

Surveillance is an important tool for infection control; however, this task can often be time-consuming and take away from infection prevention activities. With the increasing availability of comprehensive electronic health records, there is an opportunity to automate these surveillance activities. The objective of this article is to describe the implementation of an electronic algorithm for ventilator-associated events (VAEs) at a large academic medical center METHODS: This article reports on a 6-month manual validation of a dashboard for VAEs. We developed a computerized algorithm for automatically detecting VAEs and compared the output of this algorithm to the traditional, manual method of VAE surveillance.

RESULTS

Manual surveillance by the infection preventionists identified 13 possible and 11 probable ventilator-associated pneumonias (VAPs), and the VAE dashboard identified 16 possible and 13 probable VAPs. The dashboard had 100% sensitivity and 100% accuracy when compared with manual surveillance for possible and probable VAP. We report on the successfully implemented VAE dashboard. Workflow of the infection preventionists was simplified after implementation of the dashboard with subjective time-savings reported.

CONCLUSIONS

Implementing a computerized dashboard for VAE surveillance at a medical center with a comprehensive electronic health record is feasible; however, this required significant initial and ongoing work on the part of data analysts and infection preventionists.

Infection control link nurse program: an interdisciplinary approach in targeting health care-acquired infection

BACKGROUND

We describe a successful interdisciplinary liaison program that effectively reduced health care-acquired (HCA), methicillin-resistant Staphylococcus aureus (MRSA) in a university hospital setting.

METHODS

Baseline was from January 2006 to March 2008, and intervention period was April 2008 to September 2009. Staff nurses were trained to be liaisons (link nurses) to infection prevention (IP) personnel with clearly defined goals assigned and with ongoing monthly education. HCA-MRSA incidence per 1,000 patient-days (PD) was compared between baseline and intervention period along with total and non-HCA-MRSA, HCA and non-HCA-MRSA bacteremia, and hand soap/sanitizer usage. Hand hygiene compliance was assessed.

RESULTS

A reduction in MRSA rates was as follows in intervention period compared with baseline: HCA-MRSA decreased by 28% from 0.92 to 0.67 cases per 1,000 PD (incidence rate ratio, 0.72; 95% confidence interval: 0.62-0.83, P < .001), and HCA-MRSA bacteremia rate was reduced by 41% from 0.18 to 0.10 per 1,000 PD (incidence rate ratio, 0.59; 95% confidence interval: 0.42-0.84, P = .003). Total MRSA rate and MRSA bacteremia rate also showed significant reduction with nonsignificant reductions in overall non-HCA-MRSA and non-HCA-MRSA bacteremia. Hand soap/sanitizer usage and compliance with hand hygiene also increased significantly during IP.

CONCLUSION

Link nurse program effectively reduced HCA-MRSA. Goal-defined metrics with ongoing re-education for the nurses by IP personnel helped drive these results.