SARS-CoV-2 asymptomatic surveillance testing (AST) is a common strategy to minimize the risk of nosocomial infection in patients and healthcare personnel. In contrast to admission screening, post-admission AST was less widely adopted.

This study describes the diagnostic yield of post-admission serial SARS-COV-2 testing in hospitalized patients at a large cancer center with mostly double-occupancy rooms.

Retrospective cohort study design. Post-admission SARS-CoV-2 tests were examined over a 18 month study period. Positive results were reviewed to determine true hospital-onset infections using a combination criteria of screening all sample cycle threshold (Ct) values >30, results of non-concordant repeat testing, and clinical symptoms.

Post-admission serial testing of 15,048 hospitalized patients during an 18-month study period at a tertiary care cancer center detected hospital-onset infection in 1.6% (n = 245 patients). Among all hospital-onset positive SARS-CoV-2 RNA tests, 13% were clinically false positive. Most true infections were mild to moderate in severity.

In summary, post-admission serial testing in a high-risk setting is a low-yield strategy with several unfavorable effects and should no longer be routinely applied.

Universal masking within healthcare settings was adopted to combat the spread of coronavirus disease 2019 (COVID-19). In addition to mitigating the risk for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, it also had an added benefit of preventing the nosocomial transmission of other respiratory viral diseases.

This study examines the impact of the masking intervention on nosocomial respiratory viral infections (RVI) in vulnerable sub-populations of people with cancer at a tertiary care hospital.

Interrupted time series analysis.

We reviewed non-SARS-CoV-2 nosocomial RVI between January 1, 2017 and December 31, 2023 and compared its quarterly trends before (January 2017 to March 2020) and after (April 2020 to December 2023) the universal masking intervention was implemented.

Prior to the masking policy, there was no significant change in the quarterly rate of non-SARS-CoV-2 nosocomial RVI (baseline trend: P = 0.662). Crude infection rates decreased from 5.6% preintervention to 4.3% after the masking policy was implemented (P < 0.001). Quarterly trends continued to steadily decline post-intervention (β = −0.10, SE = 0.04, P < 0.007).

Our results suggest that universal face masking is associated with reduced non-SARS-CoV-2 nosocomial RVI, providing further evidence to support the continued use of face masks in healthcare settings to protect the health of immunocompromised patients.

To determine the effectiveness of ultraviolet (UV) environmental disinfection system on rates of hospital-acquired vancomycin-resistant enterococcus (VRE) and Clostridium difficile.

Using active surveillance and an interrupted time-series design, hospital-acquired acquisition of VRE and C. difficile on a bone marrow transplant (BMT) unit were examined before and after implementation of terminal disinfection with UV on all rooms regardless of isolation status of patients. The main outcomes were hospital-based acquisition measured through (1) active surveillance: admission, weekly, and discharge screening for VRE and toxigenic C. difficile (TCD) and (2) clinical surveillance: incidence of VRE and CDI on the unit.

Bone marrow transplant unit at a tertiary-care cancer center.

Stem cell transplant (SCT) recipients.

Terminal disinfection of all rooms with UV regardless of isolation status of patients.

During the 20-month study period, 579 patients had 704 admissions to the BMT unit, and 2,160 surveillance tests were performed. No change in level or trend in the incidence of VRE (trend incidence rate ratio [IRR], 0.96; 95% confidence interval [CI], 0.81–1.14; level IRR, 1.34; 95% CI, 0.37–1.18) or C. difficile (trend IRR, 1.08; 95% CI, 0.89–1.31; level IRR, 0.51; 95% CI, 0.13–2.11) was observed after the intervention.

Utilization of UV disinfection to supplement routine terminal cleaning of rooms was not effective in reducing hospital-acquired VRE and C. difficile among SCT recipients.

Surgical site infections (SSIs) following colorectal surgery (CRS) are among the most common healthcare-associated infections (HAIs). Reduction in colorectal SSI rates is an important goal for surgical quality improvement.

To examine rates of SSI in patients with and without cancer and to identify potential predictors of SSI risk following CRS

American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) data files for 2011–2013 from a sample of 12 National Comprehensive Cancer Network (NCCN) member institutions were combined. Pooled SSI rates for colorectal procedures were calculated and risk was evaluated. The independent importance of potential risk factors was assessed using logistic regression.

Multicenter study

Of 22 invited NCCN centers, 11 participated (50%). Colorectal procedures were selected by principal procedure current procedural technology (CPT) code. Cancer was defined by International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) codes.

The primary outcome of interest was 30-day SSI rate.

A total of 652 SSIs (11.06%) were reported among 5,893 CRSs. Risk of SSI was similar for patients with and without cancer. Among CRS patients with underlying cancer, disseminated cancer (SSI rate, 17.5%; odds ratio [OR], 1.66; 95% confidence interval [CI], 1.23–2.26; P=.001), ASA score ≥3 (OR, 1.41; 95% CI, 1.09–1.83; P=.001), chronic obstructive pulmonary disease (COPD; OR, 1.6; 95% CI, 1.06–2.53; P=.02), and longer duration of procedure were associated with development of SSI.

Patients with disseminated cancer are at a higher risk for developing SSI. ASA score >3, COPD, and longer duration of surgery predict SSI risk. Disseminated cancer should be further evaluated by the Centers for Disease Control and Prevention (CDC) in generating risk-adjusted outcomes.

Infect Control Hosp Epidemiol 2018;39:555–562

In this study, we sought to evaluate the performance of the Xpert MTB/RIF (Cepheid) assay for the detection of Mycobacterium tuberculosis (MTB) complex DNA on fresh and formalin-fixed, paraffin-embedded (FFPE) tissue specimens from oncology patients in an area with a low prevalence of tuberculosis. We also aimed to retrospectively assess the potential impact of Xpert MTB/RIF on the duration of airborne infection isolation (AII).

A 473-bed, tertiary-care cancer center in New York City.

A total of 203 tissue samples (101 FFPE and 102 fresh) were tested using Xpert MTB/RIF, including 133 pulmonary tissue samples (65.5%) and 70 extrapulmonary tissue samples (34.5%). Acid-fast bacilli (AFB) culture was used as the diagnostic gold standard. The limit of detection (LOD) and reproducibility were also evaluated for both samples types using contrived specimens. The potential impact of the Xpert MTB PCR assay on tissue samples from AII patients on AII duration was retrospectively assessed.

Using the Xpert MTB/RIF for fresh tissue specimens, the sensitivity was 50% (95% CI, 1.3%–98.7%) and the specificity was 99% (95% CI, 94.5%–99.9%). For FFPE tissue specimens, the sensitivity was 100% (95% CI, 63.1%–100%) and the specificity was 98.3% (95% CI, 95.5%–100%. The LOD was 103 colony-forming units (CFU)/mL for both fresh and FFPE tissue specimens, and the Xpert MTB/RIF was 100% reproducible at concentrations 10 times that of the LOD. With an expected turnaround time of 24 hours, the Xpert MTB PCR could decrease the duration of AII from a median of 8 days to a median of 1 day.

The Xpert MTB/RIF assay offers a valid option for ruling out Mycobacterium tuberculosis complex (MTBC) on tissue samples from oncology patients and for minimizing AII resource utilization.

Infect Control Hosp Epidemiol 2018;39:462–466

To describe the utilization of electronic medical data resources, including health records and nursing scheduling resources, to conduct a tuberculosis (TB) exposure investigation in a high-risk oncology unit.

A 42-bed inpatient unit with a mix of surgical and medical patients at a large tertiary-care cancer center in New York City.

High-risk subjects and coworkers exposed to a healthcare worker (HCW) with cavitary smear positive lung TB.

During the 3-month exposure period, 270 patients were admitted to the unit; 137 of these (50.7%) received direct care from the index case HCW. Host immune status and intensity of exposure were used to establish criteria for postexposure testing, and 63 patients (45%) met these criteria for first-tier postexposure testing. No cases of active TB occurred. Among coworkers, 146 had significant exposure (ie, >8 hours cumulative). In the 22-month follow-up period after the exposure, no purified protein derivative or interferon gamma release assay conversions or active cases of TB occurred among exposed HCWs or patients.

Electronic medical records and employee scheduling systems are useful resources to conduct otherwise labor-intensive contact investigations. Despite the high-risk features of our index case, a highly vulnerable immunocompromised patient population, and extended proximity to coworkers, we did not find any evidence of transmission of active or latent tuberculosis infection among exposed individuals.

Infect Control Hosp Epidemiol 2017;38:1235–1239

To determine the role of unit-based transmission that accounts for cases of early Clostridium difficile infection (CDI) during hospitalization for allogeneic stem cell transplant.

Stem cell transplant unit at a tertiary care cancer center.

Serially collected stool from patients admitted for transplant was screened for toxigenic C. difficile through the hospital stay and genotyping was performed by multilocus sequence typing. In addition, isolates retrieved from cases of CDI that occurred in other patients hospitalized on the same unit were similarly characterized. Transmission links were established by time-space clustering of cases and carriers of shared toxigenic C. difficile strains.

During the 27-month period, 1,099 samples from 264 patients were screened, 69 of which had evidence of toxigenic C. difficile; 52 patients developed CDI and 17 were nonsymptomatic carriers. For the 52 cases, 41 had evidence of toxigenic C. difficile on the first study sample obtained within a week of admission, among which 22 were positive within the first 48 hours. A total of 24 sequence types were isolated from this group; 1 patient had infection with the NAP1 strain. A total of 11 patients had microbiologic evidence of acquisition; donor source could be established in half of these cases.

Most cases of CDI after stem cell transplant represent delayed onset disease in nonsymptomatic carriers. Transmission on stem cell transplant unit was confirmed in 19% of early CDI cases in our cohort with a probable donor source established in half of the cases.

Infect. Control Hosp. Epidemiol. 2015;37(1):8–15

In this study, we examined the impact of routine use of a passive disinfection cap for catheter hub decontamination in hematology–oncology patients.

A tertiary care cancer center in New York City

In this multiphase prospective study, we used 2 preintervention phases (P1 and P2) to establish surveillance and baseline rates followed by sequential introduction of disinfection caps on high-risk units (HRUs: hematologic malignancy wards, hematopoietic stem cell transplant units and intensive care units) (P3) and general oncology units (P4). Unit-specific and hospital-wide hospital-acquired central-line–associated bloodstream infection (HA-CLABSI) rates and blood culture contamination (BCC) with coagulase negative staphylococci (CONS) were measured.

Implementation of a passive disinfection cap resulted in a 34% decrease in hospital-wide HA-CLABSI rates (combined P1 and P2 baseline rate of 2.66–1.75 per 1,000 catheter days at the end of the study period). This reduction occurred only among high-risk patients and not among general oncology patients. In addition, the use of the passive disinfection cap resulted in decreases of 63% (HRUs) and 51% (general oncology units) in blood culture contamination, with an estimated reduction of 242 BCCs with CONS. The reductions in HA-CLABSI and BCC correspond to an estimated annual savings of $3.2 million in direct medical costs.

Routine use of disinfection caps is associated with decreased HA-CLABSI rates among high-risk hematology oncology patients and a reduction in blood culture contamination among all oncology patients.

Infect. Control Hosp. Epidemiol. 2015;36(12):1401–1408