Comparative antimicrobial use in coronavirus disease 2019 (COVID-19) and non-COVID-19 inpatients from 2019 to 2020: A multicenter ecological study.

OBJECTIVE: We sought to determine whether increased antimicrobial use (AU) at the onset of the coronavirus disease 2019 (COVID-19) pandemic was driven by greater AU in COVID-19 patients only, or whether AU also increased in non-COVID-19 patients. DESIGN: In this retrospective observational ecological study from 2019 to 2020, we stratified inpatients by COVID-19 status and determined relative percentage differences in median monthly AU in COVID-19 patients versus non-COVID-19 patients during the COVID-19 period (March-December 2020) and the pre-COVID-19 period (March-December 2019). We also determined relative percentage differences in median monthly AU in non-COVID-19 patients during the COVID-19 period versus the pre-COVID-19 period. Statistical significance was assessed using Wilcoxon signed-rank tests. SETTING: The study was conducted in 3 acute-care hospitals in Chicago, Illinois. PATIENTS: Hospitalized patients. RESULTS: Facility-wide AU for broad-spectrum antibacterial agents predominantly used for hospital-onset infections was significantly greater in COVID-19 patients versus non-COVID-19 patients during the COVID-19 period (with relative increases of 73%, 66%, and 91% for hospitals A, B, and C, respectively), and during the pre-COVID-19 period (with relative increases of 52%, 64%, and 66% for hospitals A, B, and C, respectively). In contrast, facility-wide AU for all antibacterial agents was significantly lower in non-COVID-19 patients during the COVID-19 period versus the pre-COVID-19 period (with relative decreases of 8%, 7%, and 8% in hospitals A, B, and C, respectively). CONCLUSIONS: AU for broad-spectrum antimicrobials was greater in COVID-19 patients compared to non-COVID-19 patients at the onset of the pandemic. AU for all antibacterial agents in non-COVID-19 patients decreased in the COVID-19 period compared to the pre-COVID-19 period.

Computing antimicrobial use/antimicrobial resistance ratios: A novel way to assess inpatient antimicrobial utilization using current National Healthcare Safety Network metrics.

BACKGROUND: Current methods for benchmarking inpatient antimicrobial use (AU) could benefit from combining AU with antimicrobial resistance (AR) information to provide metrics benchmarked to microbiological data; this may yield more instructive and better risk-adjusted measurements than AU and AR in isolation. METHODS: In this retrospective single-center study, we computed facility-wide AU/AR ratios from 2019 to 2020 for specific antimicrobial agents and corresponding AR events, and compared median monthly AU/AR ratios between March 2019 through December 2019 (pre-COVID period) and March 2020 through December 2020 (COVID period). Aggregate AU was expressed as a ratio to aggregate AR events for antimicrobials that typically have activity against the AR organism and are frequently used to treat the AR organism in clinical practice. We also computed AU/AR ratios in our surgical intensive care unit in the pre-COVID period. RESULTS: High-median facility-wide monthly AU/AR ratios were observed for intravenous vancomycin/methicillin-resistant Staphylococcus aureus, with 130.0 in the pre-COVID period and 121.3 in the COVID period (p =.520). Decreases in facility-wide median monthly AU/AR ratios were observed between periods for meropenem/ESBL Enterobacterales (20.9 vs. 7.9, p < .001), linezolid/vancomycin-resistant Enterococcus (48.5 vs. 15.8, p =.004), and daptomycin/vancomycin-resistant Enterococcus (32.2 vs. 4.8, p = .002). Increases in facility-wide median monthly AU/AR ratios were observed between periods for ceftazidime-avibactam/carbapenem-resistant Enterobacterales (0.0 vs. 3.2, p = .020) and ceftazidime-avibactam/multidrug-resistant Pseudomonas aeruginosa (0.0 vs. 4.0, p = .017). The AU/AR ratio for intravenous vancomycin/methicillin-resistant S. aureus in the surgical intensive care unit was 191.5 in the pre-COVID period. CONCLUSIONS: AU/AR ratios may be used to supplement current AU and AR metrics. Future directions should include the development of more AU metrics benchmarked to microbiological information. AU metrics more specific to transplant infectious diseases should be developed.

Hospital-acquired coronavirus disease 2019 (COVID-19) among patients of two acute-care hospitals: Implications for surveillance.

OBJECTIVES: We quantified hospital-acquired coronavirus disease 2019 (COVID-19) during the early phases of the pandemic, and we evaluated solely temporal determinations of hospital acquisition. DESIGN: Retrospective observational study during early phases of the COVID-19 pandemic, March 1-November 30, 2020. We identified laboratory-detected severe acute respiratory coronavirus virus 2 (SARS-CoV-2) from 30 days before admission through discharge. All cases detected after hospital day 5 were categorized by chart review as community or unlikely hospital-acquired cases, or possible or probable hospital-acquired cases. SETTING: The study was conducted in 2 acute-care hospitals in Chicago, Illinois. PATIENTS: The study included all hospitalized patients including an inpatient rehabilitation unit. INTERVENTIONS: Each hospital implemented infection-control precautions soon after identifying COVID-19 cases, including patient and staff cohort protocols, universal masking, and restricted visitation policies. RESULTS: Among 2,667 patients with SARS-CoV-2, detection before hospital day 6 was most common (n = 2,612; 98%); detection during hospital days 6-14 was uncommon (n = 43; 1.6%); and detection after hospital day 14 was rare (n = 16; 0.6%). By chart review, most cases after day 5 were categorized as community acquired, usually because SARS-CoV-2 had been detected at a prior healthcare facility (68% of cases on days 6-14 and 53% of cases after day 14). The incidence rates of possible and probable hospital-acquired cases per 10,000 patient days were similar for ICU- and non-ICU patients at hospital A (1.2 vs 1.3 difference, 0.1; 95% CI, -2.8 to 3.0) and hospital B (2.8 vs 1.2 difference, 1.6; 95% CI, -0.1 to 4.0). CONCLUSIONS: Most patients were protected by early and sustained application of infection-control precautions modified to reduce SARS-CoV-2 transmission. Using solely temporal criteria to discriminate hospital versus community acquisition would have misclassified many "late onset" SARS-CoV-2-positive cases.

Diverse virulence gene content of Shiga toxin-producing Escherichia coli from finishing swine.

Shiga toxin-producing Escherichia coli (STEC) infections are a critical public health concern because they can cause severe clinical outcomes, such as hemolytic uremic syndrome, in humans. Determining the presence or absence of virulence genes is essential in assessing the potential pathogenicity of STEC strains. Currently, there is limited information about the virulence genes carried by swine STEC strains; therefore, this study was conducted to examine the presence and absence of 69 virulence genes in STEC strains recovered previously from finishing swine in a longitudinal study. A subset of STEC strains was analyzed by pulsed-field gel electrophoresis (PFGE) to examine their genetic relatedness. Swine STEC strains (n = 150) were analyzed by the use of a high-throughput real-time PCR array system, which included 69 virulence gene targets. Three major pathotypes consisted of 16 different combinations of virulence gene profiles, and serotypes were determined in the swine STEC strains. The majority of the swine STEC strains (n = 120) belonged to serotype O59:H21 and carried the same virulence gene profile, which consisted of 9 virulence genes: stx2e, iha, ecs1763, lpfAO113, estIa (STa), ehaA, paa, terE, and ureD. The eae, nleF, and nleH1-2 genes were detected in one swine STEC strain (O49:H21). Other genes encoding adhesins, including iha, were identified (n = 149). The PFGE results demonstrated that swine STEC strains from pigs raised in the same finishing barn were closely related. Our results revealed diverse virulence gene contents among the members of the swine STEC population and enhance understanding of the dynamics of transmission of STEC strains among pigs housed in the same barn.

Shiga toxin-producing Escherichia coli in swine: the public health perspective.

Shiga toxin-producing Escherichia coli (STEC) strains are food-borne pathogens that are an important public health concern. STEC infection is associated with severe clinical diseases in human beings, including hemorrhagic colitis (HC) and hemolytic uremic syndrome (HUS), which can lead to kidney failure and death. Cattle are the most important STEC reservoir. However, a number of STEC outbreaks and HUS cases have been attributed to pork products. In swine, STEC strains are known to be associated with edema disease. Nevertheless, the relationship between STEC of swine origin and human illness has yet to be determined. This review critically summarizes epidemiologic and biological studies of swine STEC. Several epidemiologic studies conducted in multiple regions of the world have demonstrated that domestic swine can carry and shed STEC. Moreover, animal studies have demonstrated that swine are susceptible to STEC O157:H7 infection and can shed the bacterium for 2 months. A limited number of molecular epidemiologic studies, however, have provided conflicting evidence regarding the relationship between swine STEC and human illness. The role that swine play in STEC transmission to people and the contribution to human disease frequency requires further evaluation.

Mustelid herpesvirus-2, a novel herpes infection in northern sea otters (Enhydra lutris kenyoni).

Oral ulcerations and plaques with epithelial eosinophilic intranuclear inclusions were observed in northern sea otters (Enhydra lutris kenyoni) that died or were admitted for rehabilitation after the 1989 Exxon Valdez oil spill (EVOS) in Alaska, USA. Transmission electron microscopy demonstrated the presence of herpesviral virions. Additionally, a serologic study from 2004 to 2005 found a high prevalence of exposure to a herpesvirus in live-captured otters. Tissues from 29 otters after the EVOS and nasal swabs from 83 live-captured otters in the Kodiak Archipelago were tested for herpesviral DNA. Analysis identified a novel herpesvirus in the gamma subfamily, most closely related to Mustelid herpesvirus-1 from badgers. Results indicated that this herpesvirus is associated with ulcerative lesions but is also commonly found in secretions of healthy northern sea otters.