A multicenter evaluation of antibacterial use in hospitalized patients through the SARS-Cov-2 pandemic waves.

BACKGROUND: Excessive use of antibiotics has been reported during the SARS-CoV-2 pandemic. We evaluated trends in antibiotic use and culture positive Gram-negative (GN)/Gram-positive (GP) pathogens in US hospitalized patients before and during the SARS-CoV-2 pandemic. METHODS: This multicenter, retrospective study included patients from 271 US facilities with > 1-day inpatient admission with discharge or death between July 1, 2019, and October 30, 2021, in the BD Insights Research Database. We evaluated microbiological testing data, antibacterial use, defined as antibacterial use ≥ 24 h in admitted patients, and duration of antibacterial therapy. RESULTS: Of 5,518,744 patients included in the analysis, 3,729,295 (67.6%) patients were hospitalized during the pandemic with 2,087,774 (56.0%) tested for SARS-CoV-2 and 189,115 (9.1%) testing positive for SARS-CoV-2. During the pre-pandemic period, 36.2% were prescribed antibacterial therapy and 9.3% tested positive for select GN/GP pathogens. During the SARS-CoV-2 pandemic, antibacterial therapy (57.8%) and positive GN/GP culture (11.9%) were highest in SARS-CoV-2-positive patients followed by SARS-CoV-2-negative patients (antibacterial therapy, 40.1%; GN/GP, pathogens 11.0%), and SARS-CoV-2 not tested (antibacterial therapy 30.4%; GN/GP pathogens 7.2%). Multivariate results showed significant decreases in antibacterial therapy and positive GN/GP cultures for both SARS-CoV-2-positive and negative patients during the pandemic, but no significant overall changes from the pre-pandemic period to the pandemic period. CONCLUSIONS: There was a decline in both antibacterial use and positive GN/GP pathogens in patients testing positive for SARS-CoV-2. However, overall antibiotic use was similar prior to and during the pandemic. These data may inform future efforts to optimize antimicrobial stewardship and prescribing.

Estimated BNT162b2 Vaccine Effectiveness Against Infection With Delta and Omicron Variants Among US Children 5 to 11 Years of Age.

Importance: Data describing the vaccine effectiveness (VE) and durability of BNT162b2 among children 5 to 11 years of age are needed. Objective: To estimate BNT162b2 VE against SARS-CoV-2 infection among children aged 5 to 11 years during Delta and Omicron variant-predominant periods and to further assess VE according to prior SARS-CoV-2 infection status and by sublineage during the Omicron variant-predominant period. Design, Setting, and Participants: This test-negative case-control study was conducted from November 2 to December 9, 2021 (Delta variant), and from January 16 to September 30, 2022 (Omicron variant), among 160 002 children tested at a large national US retail pharmacy chain, for SARS-CoV-2 via polymerase chain reaction (PCR); 62 719 children were tested during the Delta period, and 97 283 were tested during the Omicron period. Exposure: Vaccination with BNT162b2 before SARS-CoV-2 testing vs no vaccination. Main Outcomes and Measures: The primary outcome was SARS-CoV-2 infection confirmed by PCR (regardless of the presence of symptoms), and the secondary outcome was confirmed symptomatic infection. Adjusted estimated VE was calculated from multilevel logistic regression models. Results: A total of 39 117 children tested positive and 131 686 tested negative for SARS-CoV-2 (total, 170 803; 84 487 [49%] were boys; mean [SD] age was 9 [2] years; 74 236 [43%] were White non-Hispanic or non-Latino; and 37 318 [22%] were Hispanic or Latino). Final VE analyses included 160 002 children without SARS-CoV-2 infection less than 90 days prior. The VE of 2 doses of BNT162b2 against Delta was 85% (95% CI, 80%-89%; median follow-up, 1 month) compared with the Omicron period (20% [95% CI, 17%-23%]; median follow-up, 4 months). The adjusted VE of 2 doses against Omicron at less than 3 months was 39% (95% CI, 36%-42%), and at 3 months or more, it was -1% (95% CI, -6% to 3%). Protection against Omicron was higher among children with vs without infection 90 days or more prior but decreased in all children approximately 3 months after the second dose (58% [95% CI, 49%-66%] with infection vs 37% [95% CI, 34%-41%] without infection at <3 months; 27% [95% CI, 17%-35%] with infection vs -7% [95% CI, -12% to -1%] at ≥3 months without infection). The VE of 2 doses of BNT162b2 at less than 3 months by Omicron sublineage was 40% (95% CI, 36%-43%) for BA.1, 32% (95% CI, 21%-41%) for BA.2/BA.2.12.1, and 50% (95% CI, 37%-60%) for BA.4/BA.5. After 3 months or more, VE was nonsignificant for BA.2/BA.2.12.1 and BA.4/BA.5. The VE of a booster dose was 55% (95% CI, 50%-60%) against Omicron, with no evidence of waning at 3 months or more. Conclusions and Relevance: This study suggests that, among children aged 5 to 11 years, 2 doses of BNT162b2 provided modest short-term protection against Omicron infection that was higher for those with prior infection; however, VE waned after approximately 3 months in all children. A booster dose restored protection against Omicron and was maintained for at least 3 months. These findings highlight the continued importance of booster vaccination regardless of history of prior COVID-19.

A Multicenter Comparison of Prevalence and Predictors of Antimicrobial Resistance in Hospitalized Patients Before and During the Severe Acute Respiratory Syndrome Coronavirus 2 Pandemic.

Background: Antibacterial therapy is frequently used in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) without evidence of bacterial infection, prompting concerns about increased antimicrobial resistance (AMR). We evaluated trends in AMR before and during the SARS-CoV-2 pandemic. Methods: This multicenter, retrospective cohort analysis included hospitalized adults aged ≥18 years with >1-day inpatient admission and a record of discharge or death from 271 US facilities in the BD Insights Research Database. We evaluated rates of AMR events, defined as positive cultures for select gram-negative and gram-positive pathogens from any source, with nonsusceptibility reported by commercial panels before (1 July 2019-29 February 2020) and during (1 March 2020-30 October 2021) the SARS-CoV-2 pandemic. Results: Of 5 518 666 admissions evaluated, AMR rates per 1000 admissions were 35.4 for the prepandemic period and 34.7 for the pandemic period (P ≤ .0001). In the pandemic period, AMR rates per 1000 admissions were 49.2 for SARS-CoV-2-positive admissions, 41.1 for SARS-CoV-2-negative admissions, and 25.7 for patients untested (P ≤ .0001). AMR rates per 1000 admissions among community-onset infections during the pandemic were lower versus prepandemic levels (26.1 vs 27.6; P < .0001), whereas AMR rates for hospital-onset infections were higher (8.6 vs 7.7; P < .0001), driven largely by SARS-CoV-2-positive admissions (21.8). AMR rates were associated with overall antimicrobial use, rates of positive cultures, and higher use of inadequate empiric therapy. Conclusions: Although overall AMR rates did not substantially increase from prepandemic levels, patients tested for SARS-CoV-2 infection had a significantly higher rate of AMR and hospital-onset infections. Antimicrobial and diagnostic stewardship is key to identifying this high-risk AMR population.

Epidemiology and outcomes of culture-positive bloodstream pathogens prior to and during the SARS-CoV-2 pandemic: a multicenter evaluation.

BACKGROUND: Bloodstream infections (BSIs) are an important cause of morbidity and mortality in hospitalized patients. We evaluate incidence of community- and hospital-onset BSI rates and outcomes before and during the SARS-CoV-2 pandemic. METHODS: We conducted a retrospective cohort study evaluating patients who were hospitalized for ≥ 1 day with discharge or death between June 1, 2019, and September 4, 2021, across 271 US health care facilities. Community- and hospital-onset BSI and related outcomes before and during the SARS-CoV-2 pandemic, including intensive care admission rates, and overall and ICU-specific length of stay (LOS) was evaluated. Bivariate correlations were calculated between the pre-pandemic and pandemic periods overall and by SARS-CoV-2 testing status. RESULTS: Of 5,239,692 patient admissions, there were 20,113 community-onset BSIs before the pandemic (11.2/1000 admissions) and 39,740 (11.5/1000 admissions) during the pandemic (P ≤ 0.0062). Corresponding rates of hospital-onset BSI were 2,771 (1.6/1000 admissions) and 6,864 (2.0/1000 admissions; P < 0.0062). Compared to the pre-pandemic period, rates of community-onset BSI were higher in patients who tested negative for SARS-CoV-2 (15.8/1000 admissions), compared with 9.6/1000 BSI admissions among SARS-CoV-2-positive patients. Compared with patients in the pre-pandemic period, SARS-CoV-2-positive patients with community-onset BSI experienced greater ICU admission rates (36.6% vs 32.8%; P < 0.01), greater ventilator use (10.7% vs 4.7%; P < 0.001), and longer LOS (12.2 d vs 9.1 d; P < 0.001). Rates of hospital-onset BSI were higher in the pandemic vs the pre-pandemic period (2.0 vs 1.5/1000; P < 0.001), with rates as high a 7.3/1000 admissions among SARS-CoV-2-positive patients. Compared to the pre-pandemic period, SARS-CoV-2-positive patients with hospital-onset BSI had higher rates of ICU admission (72.9% vs 55.4%; P < 0.001), LOS (34.8 d vs 25.5 d; P < 0.001), and ventilator use (52.9% vs 21.5%; P < 0.001). Enterococcus species, Staphylococcus aureus, Klebsiella pneumoniae, and Candida albicans were more frequently detected in the pandemic period. CONCLUSIONS AND RELEVANCE: This nationally representative study found an increased risk of both community-onset and hospital-onset BSI during the SARS-CoV-2 pandemic period, with the largest increased risk in hospital-onset BSI among SARS-CoV-2-positive patients. SARS-CoV-2 positivity was associated with worse outcomes.

Mortality Among US Patients Hospitalized With SARS-CoV-2 Infection in 2020.

Importance: Mortality is an important measure of the severity of a pandemic. This study aimed to understand how mortality by age of hospitalized patients who were tested for SARS-CoV-2 has changed over time. Objective: To evaluate trends in in-hospital mortality among patients who tested positive for SARS-CoV-2. Design, Setting, and Participants: This retrospective cohort study included patients who were hospitalized for at least 1 day at 1 of 209 US acute care hospitals of variable size, in urban and rural areas, between March 1 and November 21, 2020. Eligible patients had a SARS-CoV-2 polymerase chain reaction (PCR) or antigen test within 7 days of admission or during hospitalization, and a record of discharge or in-hospital death. Exposure: SARS-CoV-2 positivity. Main Outcomes and Measures: SARS-CoV-2 infection was defined as a positive SARS-CoV-2 PCR or antigen test within 7 days before admission or during hospitalization. Mortality was extracted from electronically available data. Results: Among 503 409 admitted patients, 42 604 (8.5%) had SARS-CoV-2-positive tests. Of those with SARS-CoV-2-positive tests, 21 592 (50.7%) were male patients. Hospital admissions among patients with SARS-CoV-2-positive tests were highest in the group aged 65 years or older (19 929 [46.8%]), followed by those aged 50 to 64 years (11 602 [27.2%]) and 18 to 49 years (10 619 [24.9%]). Hospital admissions among patients 18 to 49 years of age increased from 1099 of 5319 (20.7%) in April to 1266 of 4184 (30.3%) in June and 2156 of 7280 (29.6%) in July, briefly exceeding those in the group 50 to 64 years of age (June: 1194 of 4184 [28.5%]; 2039 of 7280 [28.0%]). Patients with SARS-CoV-2-positive tests had higher in-hospital mortality than patients with SARS-CoV-2-negative tests (4705 [11.0%] vs 11 707 of 460 805 [2.5%]; P < .001). In-hospital mortality rates increased with increasing age for both patients with SARS-CoV-2-negative tests and SARS-CoV-2-positive tests. In patients with SARS-CoV-2-negative tests, mortality increased from 45 of 11 255 (0.4%) in those younger than 18 years to 4812 of 107 394 (4.5%) in those older than 75 years. In patients with SARS-CoV-2-positive tests, mortality increased from 1 of 454 (0.2%) of those younger than 18 years to 2149 of 10 287 (20.9%) in those older than 75 years. In-hospital mortality rates among patients with SARS-CoV-2-negative tests were similar for male and female patients (6273 of 209 086 [3.0%] vs 5538 of 251 719 [2.2%]) but higher mortality was observed among male patients with SARS-CoV-2-positive tests (2700 of 21 592 [12.5%]) compared with female patients with SARS-CoV-2-positive tests (2016 of 21 012 [9.60%]). Overall, in-hospital mortality increased from March to April (63 of 597 [10.6%] to 1047 of 5319 [19.7%]), then decreased significantly to November (499 of 5350 [9.3%]; P = .04), with significant decreases in the oldest age groups (50-64 years: 197 of 1542 [12.8%] to 73 of 1341 [5.4%]; P = .02; 65-75 years: 269 of 1182 [22.8%] to 137 of 1332 [10.3%]; P = .006; >75 years: 535 of 1479 [36.2%] to 262 of 1505 [17.4%]; P = .03). Conclusions and Relevance: This nationally representative study supported the findings of smaller, regional studies and found that in-hospital mortality declined across all age groups during the period evaluated. Reductions were unlikely because of a higher proportion of younger patients with lower in-hospital mortality in the later period.