BACKGROUND: Nursing home residents experience a large burden of invasive methicillin-resistant Staphylococcus aureus (MRSA) infections. Data are limited regarding nursing home characteristics associated with differences in facility-level invasive MRSA rates. METHODS: We analyzed 2011-2015 data from CDC's Emerging Infections Program (EIP) active population- and laboratory-based surveillance for invasive MRSA cases within seven states. A nursing home-onset case was defined as MRSA cultured from a normally sterile site in a person living in a nursing home 3 days before culture collection. Facility rates were calculated as nursing home-onset cases per 100,000 resident-days. Nursing home resident-day denominators and facility characteristics were obtained from four Centers for Medicare & Medicaid Services (CMS) datasets. A general estimating equations model with a logit link assessed characteristics of the facilities with highest rates comprising 50% of nursing home MRSA cases ("high rates"). RESULTS: The 626 nursing homes in the surveillance area had 2824 invasive MRSA cases; 82% of facilities had at ≥1 case. The 20% of facilities with highest rates (≥3.84 cases/100,000 resident-days) had 50% of nursing home-onset cases. In multivariable regression, facilities with high rates were more likely to have CMS-derived characteristics of presence of a resident with a multidrug-resistant organism; or greater proportions of residents who were male, were short stay (in the facility <100 days), had a nasogastric or percutaneous gastrostomy tube, or require extensive assistance with bed repositioning; and more likely to be in an EIP area with higher hospital-onset MRSA rates. Higher registered nurses staffing levels (hours/resident/day) and higher proportions of White residents were associated with lower rates. CONCLUSIONS: Facilities with higher invasive MRSA rates served residents with more clinical and functional care needs. Increasing registered nurse staffing in high-risk facilities might assist with reduction of invasive MRSA rates. These findings could help prioritize nursing homes for future MRSA prevention work.

OBJECTIVES: This study aimed to evaluate the utility of electronic health record (EHR) diagnosis codes for monitoring SARS-CoV-2 infections among nursing home residents. DESIGN: A retrospective cohort study design was used to analyze data collected from nursing homes operating under the tradename Signature Healthcare between January 2022 and June 2023. SETTING AND PARTICIPANTS: Data from 31,136 nursing home residents across 76 facilities in Kentucky, Tennessee, Indiana, Ohio, North Carolina, Georgia, Alabama, and Virginia were included. METHODS: Resident demographics, diagnosis codes associated with clinical diagnoses (including COVID-19), and SARS-CoV-2 testing information were collected from the EHR and supplemental testing data sources. We described the rates of infection and the clinical characteristics of residents with incident-positive SARS-CoV-2 tests and new-onset COVID-19 diagnoses. Positive predictive values (PPVs) of COVID-19 diagnosis codes were calculated for residents stratified by whether a resident was continuously present in a facility for ±3 days from the diagnosis onset date listed in EHRs, using positive SARS-CoV-2 tests to confirm infection. RESULTS: A total of 4876 incident-positive SARS-CoV-2 tests and 6346 new-onset COVID-19 diagnoses were recorded during the study period. Weekly rates of new-onset diagnoses were significantly higher than positive test rates, although trends followed similar trajectories. Among residents continuously present in the nursing home ±3 days from the diagnosis onset date, the PPV of COVID-19 diagnosis codes was high (3395 of 3685 = 92%; 95% CI, 91%-93%). The PPV among this group significantly varied by study quarter (P < .001). The PPV was substantially lower for 2661 diagnoses among residents not continuously present in the nursing home (24%; 95% CI, 22%-26%). CONCLUSIONS AND IMPLICATIONS: This study demonstrates the utility of diagnosis codes for assessment of COVID-19 epidemiology and trends when testing data are unavailable for residents during their stay in a nursing home. Future research should explore strategies to evaluate the utility of diagnosis codes at admission and discharge to nursing homes to enhance surveillance efforts.

IMPORTANCE: Multiplex molecular syndromic panels for diagnosis of urinary tract infection (UTI) lack clinical data supporting their use in routine clinical care. They also have the potential to exacerbate inappropriate antibiotic prescribing. OBJECTIVE: To describe the frequency of unspecified multiplex testing in administrative claims with a primary diagnosis of UTI in the Medicare population over time, to assess costs, and to characterize the health care professionals (eg, clinicians, laboratories, physician assistants, and nurse practitioners) and patient populations using these tests. DESIGN, SETTING, AND PARTICIPANTS: This cohort study used Centers for Medicare & Medicaid Services (CMS) claims data for Medicare beneficiaries. The study included older community-dwelling adults and nursing home residents with fee-for-service Medicare Part A and Part B benefits from January 1, 2016, to December 31, 2023. MAIN OUTCOMES AND MEASURES: Multiplex syndromic panels were identified using carrier claims (ie, claims for clinician office or laboratory services). The annual rate of claims was measured for multiplex syndromic panels with a primary diagnosis of UTI per 10 000 eligible Medicare beneficiaries. The performing and referring specialties of health care professionals listed on claims of interest and the proportion of claims that occurred among beneficiaries residing in a nursing home were described. RESULTS: Between 31 110 656 and 36 175 559 Medicare beneficiaries with fee-for-service coverage annually (2016-2023) were included in this study. In this period, 1 679 328 claims for UTI multiplex testing were identified. The median age of beneficiaries was 77 (IQR, 70-84) years; 34% of claims were from male beneficiaries and 66% were from female beneficiaries. From 2016 to 2023, the observed rate of UTI multiplex testing increased from 2.4 to 148.1 claims per 10 000 fee-for-service beneficiaries annually, and the proportion of claims that occurred among beneficiaries residing in a nursing home ranged from 1% in 2016 to 12% in 2020. In addition to laboratories or pathologists, urology was the most common clinician specialty conducting this testing. The CMS-assigned referring clinician specialty was most frequently urology or advanced practice clinician for claims among community-dwelling beneficiaries compared with internal medicine or family medicine for claims among nursing home residents. In 2023, the median cost of a multiplex test in the US was $585 (IQR, $516-$695 for Q1-Q3), which was more than 70 times higher than the median cost of $8 for a urine culture (IQR, $8-$16 for Q1-Q3). CONCLUSIONS AND RELEVANCE: This cohort study of Medicare beneficiaries with fee-for-service coverage from 2016 to 2023 found increasing use of emerging multiplex testing for UTI coupled with high costs to the Medicare program. Monitoring and research are needed to determine the effects of multiplex testing on antimicrobial use and whether there are clinical situations in which this testing may benefit patients.

During 2016-2022, Medicare part D beneficiaries filled 8,674,460 clotrimazole-betamethasone dipropionate prescriptions. Annual rates were stable (30.9 prescriptions/1,000 beneficiary-years in 2022, enough for one in every 33 beneficiaries). Diagnostic testing was infrequent, particularly among internal medicine, family medicine, and general practitioners, suggesting potential opportunities to improve diagnostic and prescribing practices.

OBJECTIVE: The 2014 US National Strategy for Combating Antibiotic-Resistant Bacteria (CARB) aimed to reduce inappropriate inpatient antibiotic use by 20% for monitored conditions, such as community-acquired pneumonia (CAP), by 2020. We evaluated annual trends in length of therapy (LOT) in adults hospitalized with uncomplicated CAP from 2013 through 2020. METHODS: We conducted a retrospective cohort study among adults with a primary diagnosis of bacterial or unspecified pneumonia using International Classification of Diseases Ninth and Tenth Revision codes in MarketScan and the Centers for Medicare & Medicaid Services databases. We included patients with length of stay (LOS) of 2-10 days, discharged home with self-care, and not rehospitalized in the 3 days following discharge. We estimated inpatient LOT based on LOS from the PINC AI Healthcare Database. The total LOT was calculated by summing estimated inpatient LOT and actual postdischarge LOT. We examined trends from 2013 to 2020 in patients with total LOT >7 days, which was considered an indicator of likely excessive LOT. RESULTS: There were 44,976 and 400,928 uncomplicated CAP hospitalizations among patients aged 18-64 years and ≥65 years, respectively. From 2013 to 2020, the proportion of patients with total LOT >7 days decreased by 25% (68% to 51%) among patients aged 18-64 years and by 27% (68%-50%) among patients aged ≥65 years. CONCLUSIONS: Although likely excessive LOT for uncomplicated CAP patients decreased since 2013, the proportion of patients treated with LOT >7 days still exceeded 50% in 2020. Antibiotic stewardship programs should continue to pursue interventions to reduce likely excessive LOT for common infections.

IMPORTANCE: Characterizing the scale and factors associated with hospital-onset SARS-CoV-2 infections could help inform hospital and public health policies regarding prevention and surveillance needs for these infections. OBJECTIVE: To evaluate associations of hospital-onset SARS-CoV-2 infection rates with different periods of the COVID-19 pandemic, hospital characteristics, and testing practices. DESIGN, SETTING, AND PARTICIPANTS: This cohort study of US hospitals reporting SARS-CoV-2 testing data in the PINC AI Healthcare Database COVID-19 special release files was conducted from July 2020 through June 2022. Data were collected from hospitals that reported at least 1 SARS-CoV-2 reverse transcription-polymerase chain reaction or antigen test during hospitalizations discharged that month. For each hospital-month where the hospital reported sufficient data, all hospitalizations discharged in that month were included in the cohort. SARS-CoV-2 viral tests and results reported in the microbiology files for all hospitalizations in the study period by discharge month were identified. Data analysis was conducted from September 2022 to March 2023. EXPOSURE: Hospitalizations discharged in an included hospital-month. MAIN OUTCOMES AND MEASURES: Multivariable generalized estimating equation negative-binomial regression models were used to assess associations of monthly rates of hospital-onset SARS-CoV-2 infections per 1000 patient-days (defined as a first positive SARS-CoV-2 test during after hospitalization day 7) with the phase of the pandemic (defined as the predominant SARS-CoV-2 variant in circulation), admission testing rates, and hospital characteristics (hospital bed size, teaching status, urban vs rural designation, Census region, and patient distribution variables). RESULTS: A total of 5687 hospital-months from 288 distinct hospitals were included, which contributed 4 421 268 hospitalization records. Among 171 564 hospitalizations with a positive SARS-CoV-2 test, 7591 (4.4%) were found to be hospital onset and 6455 (3.8%) were indeterminate onset. The mean monthly hospital-onset infection rate per 1000 patient-days was 0.27 (95 CI, 0.26-0.29). Hospital-onset infections occurred in 2217 of 5687 hospital-months (39.0%). The monthly percentage of discharged patients tested for SARS-CoV-2 at admission varied; 1673 hospital-months (29.4%) had less than 25% of hospitalizations tested at admission; 2199 hospital-months (38.7%) had 25% to 50% of all hospitalizations tested, and 1815 hospital months (31.9%) had more than 50% of all hospitalizations tested at admission. Postadmission testing rates and community-onset infection rates increased with admission testing rates. In multivariable models restricted to hospital-months testing at least 25% of hospitalizations at admission, a 10% increase in community-onset SARS-CoV-2 infection rate was associated with a 178% increase in the hospital-onset infection rate (rate ratio, 2.78; 95% CI, 2.52-3.07). Additionally, the phase of the COVID-19 pandemic, the admission testing rate, Census region, and bed size were all significantly associated with hospital-onset SARS-CoV-2 infection rates. CONCLUSIONS AND RELEVANCE: In this cohort study of hospitals reporting SARS-CoV-2 infections, there was an increase of hospital-onset SARS-CoV-2 infections when community-onset infections were higher, indicating a need for ongoing and enhanced surveillance and prevention efforts to reduce in-hospital transmission of SARS-CoV-2 infections, particularly when community-incidence of SARS-CoV-2 infections is high.

Importance: There are limited data describing SARS-CoV-2-specific immune responses and their durability following infection and vaccination in nursing home residents. Objective(s): To evaluate the quantitative titers and durability of binding antibodies detected after SARSCoV-2 infection and subsequent COVID-19 vaccination. Design(s): A prospective longitudinal evaluation included nine visits over 150 days; visits included questionnaire administration, blood collection for serology, and paired anterior nasal specimen collection for testing by BinaxNOWTM COVID-19 Ag Card (BinaxNOW), reverse transcription polymerase chain reaction (RT-PCR), and viral culture. Setting(s): A nursing home during and after a SARS-CoV-2 outbreak. Participant(s): 11 consenting SARS-CoV-2-positive nursing home residents. Main Outcomes and Measures: SARS-CoV-2 testing (BinaxNOWTM, RT-PCR, viral culture); quantitative titers of binding SARS-CoV-2 antibodies post-infection and post-vaccination (beginning after the first dose of the primary series). Result(s): Of 10 participants with post-infection serology results, 9 (90%) had detectable Pan-Ig, IgG, and IgA antibodies and 8 (80%) had detectable IgM antibodies. At first antibody detection post-infection, two-thirds (6/9, 67%) of participants were RT-PCR-positive but none were culture positive. Ten participants received vaccination; all had detectable Pan-Ig, IgG, and IgA antibodies through their final observation <=90 days post-first dose. Post-vaccination geometric means of IgG titers were 10-200-fold higher than post-infection. Conclusions and Relevance: Nursing home residents in this cohort mounted robust immune responses to SARS-CoV-2 post-infection and post-vaccination. The augmented antibody responses post-vaccination are potential indicators of enhanced protection that vaccination may confer on previously infected nursing home residents. Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available for use under a CC0 license.

One in six nursing home residents and staff with positive SARS-CoV-2 tests 90 days after initial infection had specimen cycle thresholds (Ct) <30. Individuals with specimen Ct<30 were more likely to report symptoms but were not different from individuals with high Ct value specimens by other clinical and testing data.

The authors reply: We thank Calbo and colleagues for highlighting the need to better understand the role of asymptomatic shedding in transmission of SARS-CoV-2 in health care settings. Our study focused on transmission of SARS-CoV-2 from asymptomatic and presymptomatic residents in a skilled nursing facility. As we noted, health care personnel with undetected infection probably contributed to transmission in this facility, but we could not document this because we were unable to test asymptomatic health care personnel as part of this investigation owing to limited testing resources at the time. Since that investigation, the CDC has provided guidance on testing strategies in nursing homes.1 In addition, the CDC recommends universal source control in all health care settings to help prevent transmission from health care personnel with unrecognized SARS-CoV-2 infection.2 | | The data provided by Calbo et al. suggest important hypotheses about the role of patients and health care personnel with asymptomatic SARS-CoV-2 infection in ongoing transmission in acute care facilities, a setting that is distinct from the residential skilled nursing facility described in our article. Further studies may help to better quantify the benefit of active surveillance (including laboratory testing) when added to active symptom screening and universal source control in various health care settings.

SARS-CoV-2 infections among vaccinated nursing home residents increased after the Omicron variant emerged. Data on booster dose effectiveness in this population are limited. During July 2021-March 2022, nursing home outbreaks in 11 US jurisdictions involving >3 infections within 14 days among residents who had received at least the primary COVID-19 vaccine(s) were monitored. Among 2,188 nursing homes, 1,247 outbreaks were reported in the periods of Delta (n = 356, 29%), mixed Delta/Omicron (n = 354, 28%), and Omicron (n = 536, 43%) predominance. During the Omicron-predominant period, the risk for infection within 14 days of an outbreak start was lower among boosted residents than among residents who had received the primary vaccine series alone (risk ratio [RR] 0.25, 95% CI 0.19-0.33). Once infected, boosted residents were at lower risk for all-cause hospitalization (RR 0.48, 95% CI 0.40-0.49) and death (RR 0.45, 95% CI 0.34-0.59) than primary vaccine-only residents.

Among nursing home outbreaks of coronavirus disease 2019 (COVID-19) with ≥3 breakthrough infections when the predominant severe acute respiratory coronavirus virus 2 (SARS-CoV-2) variant circulating was the SARS-CoV-2 δ (delta) variant, fully vaccinated residents were 28% less likely to be infected than were unvaccinated residents. Once infected, they had approximately half the risk for all-cause hospitalization and all-cause death compared with unvaccinated infected residents.

There are limited data describing SARS-CoV-2-specific immune responses and their durability following infection and vaccination in nursing home residents. We conducted a prospective longitudinal evaluation of 11 consenting SARS-CoV-2-positive nursing home residents to evaluate the quantitative titers and durability of binding antibodies detected after SARS-CoV-2 infection and subsequent COVID-19 vaccination. The evaluation included nine visits over 150 days from October 25, 2020, through April 1, 2021. Visits included questionnaire administration, blood collection for serology, and paired anterior nasal specimen collection for testing by BinaxNOW™ COVID-19 Ag Card (BinaxNOW), reverse transcription polymerase chain reaction (RT-PCR), and viral culture. We evaluated quantitative titers of binding SARS-CoV-2 antibodies post-infection and post-vaccination (beginning after the first dose of the primary series). The median age among participants was 74 years; one participant was immunocompromised. Of 10 participants with post-infection serology results, 9 (90%) had detectable Pan-Ig, IgG, and IgA antibodies, and 8 (80%) had detectable IgM antibodies. At first antibody detection post-infection, two-thirds (6/9, 67%) of participants were RT-PCR-positive, but none were culture- positive. Ten participants received vaccination; all had detectable Pan-Ig, IgG, and IgA antibodies through their final observation ≤90 days post-first dose. Post-vaccination geometric means of IgG titers were 10-200-fold higher than post-infection. Nursing home residents in this cohort mounted robust immune responses to SARS-CoV-2 post-infection and post-vaccination. The augmented antibody responses post-vaccination are potential indicators of enhanced protection that vaccination may confer on previously infected nursing home residents.

BACKGROUND: Residents of nursing homes experience disproportionate morbidity and mortality related to COVID-19 and were prioritized for vaccine introduction. We evaluated COVID-19 vaccine effectiveness (VE) in preventing SARS-CoV-2 infections among nursing home residents. METHODS: We used a retrospective cohort of 4,315 nursing home residents during December 14, 2020 - November 9, 2021. A Cox proportional hazards model was used to estimate hazard ratios comparing residents with a completed vaccination series to unvaccinated among those with and without prior SARS-CoV-2 infection (identified using positive SARS-CoV-2 tests and/or diagnosis codes), by vaccine product, and by period (before and during Delta variant predominance). VE was estimated as one minus the hazard ratio times 100%. RESULTS: Overall adjusted VE for the completed vaccination series was 58% (95%CI: 44%, 69%) among residents without a history of SARS-CoV-2 infection. During the pre-Delta period, the VE within 150 days of receipt of the second dose of Pfizer-BioNTech (67%, 95%CI: 40%, 82%) and Moderna (75%, 95%CI: 32%, 91%) was similar. During the Delta period, VE measured >150 days after the second dose was 33% (95%CI: -2%, 56%) for Pfizer-BioNTech and 77% (95%CI: 48%, 91%) for Moderna. Rates of infection were 78% lower (95%CI: 67%, 85%) among residents with prior SARS-CoV-2 infection and completed vaccination series compared to unvaccinated residents without a history of SARS-CoV-2 infection. CONCLUSIONS: COVID-19 vaccines were effective in preventing SARS-CoV-2 infections among nursing home residents and history of prior SARS-CoV-2 infection provided additional protection. Maintaining high coverage of recommended doses of COVID-19 vaccines remains a critical tool for preventing infections in nursing homes.

OBJECTIVES: Widespread use and misuse of prescription and illicit opioids have exposed millions to health risks including serious infectious complications. Little is known, however, about the association between opioid use and sepsis. DESIGN: Retrospective cohort study. SETTING: About 373 U.S. hospitals. PATIENTS: Adults hospitalized between January 2009 and September 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Sepsis was identified by clinical indicators of concurrent infection and organ dysfunction. Opioid-related hospitalizations were identified by the International Classification of Diseases, 9th Revision, Clinical Modification codes and/or inpatient orders for buprenorphine. Clinical characteristics and outcomes were compared by sepsis and opioid-related hospitalization status. The association between opioid-related hospitalization and all-cause, in-hospital mortality in patients with sepsis was assessed using mixed-effects logistic models to adjust for baseline characteristics and severity of illness. The cohort included 6,715,286 hospitalizations; 375,479 (5.6%) had sepsis, 130,399 (1.9%) had opioid-related hospitalizations, and 8,764 (0.1%) had both. Compared with sepsis patients without opioid-related hospitalizations (n = 366,715), sepsis patients with opioid-related hospitalizations (n = 8,764) were younger (mean 52.3 vs 66.9 yr) and healthier (mean Elixhauser score 5.4 vs 10.5), had more bloodstream infections from Gram-positive and fungal pathogens (68.9% vs 47.0% and 10.6% vs 6.4%, respectively), and had lower in-hospital mortality rates (10.6% vs 16.2%; adjusted odds ratio, 0.73; 95% CI, 0.60-0.79; p < 0.001 for all comparisons). Of 1,803 patients with opioid-related hospitalizations who died in-hospital, 928 (51.5%) had sepsis. Opioid-related hospitalizations accounted for 1.5% of all sepsis-associated deaths, including 5.7% of sepsis deaths among patients less than 50 years old. From 2009 to 2015, the proportion of sepsis hospitalizations that were opioid-related increased by 77% (95% CI, 40.7-123.5%). CONCLUSIONS: Sepsis is an important cause of morbidity and mortality in patients with opioid-related hospitalizations, and opioid-related hospitalizations contribute disproportionately to sepsis-associated deaths among younger patients. In addition to ongoing efforts to combat the opioid crisis, public health agencies should focus on raising awareness about sepsis among patients who use opioids and their providers.

Replication-competent virus has not been detected in individuals with mild to moderate COVID-19 more than 10 days after symptom onset. It is unknown whether these findings apply to nursing home residents. Of 273 specimens collected from nursing home residents >10 days from the initial positive test, none were culture positive.

Previously reported associations between hospital-level antibiotic use and hospital-onset Clostridioides difficile infection (HO-CDI) were reexamined using 2012-2018 data from a new cohort of US acute-care hospitals. This analysis revealed significant positive associations between total, third-generation, and fourth-generation cephalosporin, fluoroquinolone, carbapenem, and piperacillin-tazobactam use and HO-CDI rates, confirming previous findings.

BACKGROUND: To address high COVID-19 burden in U.S. nursing homes, rapid SARS-CoV-2 antigen tests have been widely distributed in those facilities. However, performance data are lacking, especially in asymptomatic people. OBJECTIVE: To evaluate the performance of SARS-CoV-2 antigen testing when used for facility-wide testing during a nursing home outbreak. DESIGN: A prospective evaluation involving 3 facility-wide rounds of testing where paired respiratory specimens were collected to evaluate the performance of the BinaxNOW antigen test compared with virus culture and real-time reverse transcription polymerase chain reaction (RT-PCR). Early and late infection were defined using changes in RT-PCR cycle threshold values and prior test results. SETTING: A nursing home with an ongoing SARS-CoV-2 outbreak. PARTICIPANTS: 532 paired specimens collected from 234 available residents and staff. MEASUREMENTS: Percentage of positive agreement (PPA) and percentage of negative agreement (PNA) for BinaxNOW compared with RT-PCR and virus culture. RESULTS: BinaxNOW PPA with virus culture, used for detection of replication-competent virus, was 95%. However, the overall PPA of antigen testing with RT-PCR was 69%, and PNA was 98%. When only the first positive test result was analyzed for each participant, PPA of antigen testing with RT-PCR was 82% among 45 symptomatic people and 52% among 343 asymptomatic people. Compared with RT-PCR and virus culture, the BinaxNOW test performed well in early infection (86% and 95%, respectively) and poorly in late infection (51% and no recovered virus, respectively). LIMITATION: Accurate symptom ascertainment was challenging in nursing home residents; test performance may not be representative of testing done by nonlaboratory staff. CONCLUSION: Despite lower positive agreement compared with RT-PCR, antigen test positivity had higher agreement with shedding of replication-competent virus. These results suggest that antigen testing could be a useful tool to rapidly identify contagious people at risk for transmitting SARS-CoV-2 during nascent outbreaks and help reduce COVID-19 burden in nursing homes. PRIMARY FUNDING SOURCE: None.

BACKGROUND: Treating patients with infections due to multidrug-resistant pathogens often requires substantial healthcare resources. The purpose of this study was to report estimates of the healthcare costs associated with infections due to multidrug-resistant bacteria in the United States (US). METHODS: We performed retrospective cohort studies of patients admitted for inpatient stays in the Department of Veterans Affairs healthcare system between January 2007 and October 2015. We performed multivariable generalized linear models to estimate the attributable cost by comparing outcomes in patients with and without positive cultures for multidrug-resistant bacteria. Finally, we multiplied these pathogen-specific, per-infection attributable cost estimates by national counts of infections due to each pathogen from patients hospitalized in a cohort of 722 US hospitals from 2017 to generate estimates of the population-level healthcare costs in the US attributable to these infections. RESULTS: Our analysis cohort consisted of 16 676 patients with community-onset infections and 172 712 matched controls and 8246 patients with hospital-onset infections and 66 939 matched controls. The highest cost was seen in hospital-onset invasive infections, with attributable costs (95% confidence intervals) ranging from $30 998 ($25 272-$36 724) for methicillin-resistant Staphylococcus aureus to $74 306 ($20 377-$128 235) for carbapenem-resistant (CR) Acinetobacter. The highest attributable costs for community-onset invasive infections were seen in CR Acinetobacter ($62 396; $20 370-$104 422). Treatment of these infections cost an estimated $4.6 billion ($4.1 billion-$5.1 billion) in 2017 in the US for community- and hospital-onset infections combined. CONCLUSIONS: We found that antimicrobial-resistant infections led to substantial healthcare costs.

Undetected infection with SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19) contributes to transmission in nursing homes, settings where large outbreaks with high resident mortality have occurred (1,2). Facility-wide testing of residents and health care personnel (HCP) can identify asymptomatic and presymptomatic infections and facilitate infection prevention and control interventions (3-5). Seven state or local health departments conducted initial facility-wide testing of residents and staff members in 288 nursing homes during March 24-June 14, 2020. Two of the seven health departments conducted testing in 195 nursing homes as part of facility-wide testing all nursing homes in their state, which were in low-incidence areas (i.e., the median preceding 14-day cumulative incidence in the surrounding county for each jurisdiction was 19 and 38 cases per 100,000 persons); 125 of the 195 nursing homes had not reported any COVID-19 cases before the testing. Ninety-five of 22,977 (0.4%) persons tested in 29 (23%) of these 125 facilities had positive SARS-CoV-2 test results. The other five health departments targeted facility-wide testing to 93 nursing homes, where 13,443 persons were tested, and 1,619 (12%) had positive SARS-CoV-2 test results. In regression analyses among 88 of these nursing homes with a documented case before facility-wide testing occurred, each additional day between identification of the first case and completion of facility-wide testing was associated with identification of 1.3 additional cases. Among 62 facilities that could differentiate results by resident and HCP status, an estimated 1.3 HCP cases were identified for every three resident cases. Performing facility-wide testing immediately after identification of a case commonly identifies additional unrecognized cases and, therefore, might maximize the benefits of infection prevention and control interventions. In contrast, facility-wide testing in low-incidence areas without a case has a lower proportion of test positivity; strategies are needed to further optimize testing in these settings.

Skilled nursing facilities (SNFs) are focal points of the coronavirus disease 2019 (COVID-19) pandemic, and asymptomatic infections with SARS-CoV-2, the virus that causes COVID-19, among SNF residents and health care personnel have been described (1-3). Repeated point prevalence surveys (serial testing of all residents and health care personnel at a health care facility irrespective of symptoms) have been used to identify asymptomatic infections and have reduced SARS-CoV-2 transmission during SNF outbreaks (1,3). During March 2020, the Detroit Health Department and area hospitals detected a sharp increase in COVID-19 diagnoses, hospitalizations, and associated deaths among SNF residents. The Detroit Health Department collaborated with local government, academic, and health care system partners and a CDC field team to rapidly expand SARS-CoV-2 testing and implement infection prevention and control (IPC) activities in all Detroit-area SNFs. During March 7-May 8, among 2,773 residents of 26 Detroit SNFs, 1,207 laboratory-confirmed cases of COVID-19 were identified during three periods: before (March 7-April 7) and after two point prevalence surveys (April 8-25 and April 30-May 8): the overall attack rate was 44%. Within 21 days of receiving their first positive test results, 446 (37%) of 1,207 COVID-19 patients were hospitalized, and 287 (24%) died. Among facilities participating in both surveys (n = 12), the percentage of positive test results declined from 35% to 18%. Repeated point prevalence surveys in SNFs identified asymptomatic COVID-19 cases, informed cohorting and IPC practices aimed at reducing transmission, and guided prioritization of health department resources for facilities experiencing high levels of SARS-CoV-2 transmission. With the increased availability of SARS-CoV-2 testing, repeated point prevalence surveys and enhanced and expanded IPC support should be standard tools for interrupting and preventing COVID-19 outbreaks in SNFs.

Importance: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused epidemic spread of coronavirus disease 2019 (COVID-19) in the Seattle, Washington, metropolitan area, with morbidity and mortality concentrated among residents of skilled nursing facilities. The prevalence of COVID-19 among older adults in independent/assisted living is not understood. Objectives: To conduct surveillance for SARS-CoV-2 and describe symptoms of COVID-19 among residents and staff of an independent/assisted living community. Design, Setting, and Participants: In March 2020, public health surveillance of staff and residents was conducted on site at an assisted and independent living residence for older adults in Seattle, Washington, after exposure to 2 residents who were hospitalized with COVID-19. Exposures: Surveillance for SARS-CoV-2 infection in a congregate setting implementing social isolation and infection prevention protocols. Main Outcomes and Measures: SARS-CoV-2 real-time polymerase chain reaction was performed on nasopharyngeal swabs from residents and staff; a symptom questionnaire was completed assessing fever, cough, and other symptoms for the preceding 14 days. Residents were retested for SARS-CoV-2 7 days after initial screening. Results: Testing was performed on 80 residents; 62 were women (77%), with mean age of 86 (range, 69-102) years. SARS-CoV-2 was detected in 3 of 80 residents (3.8%); none felt ill, 1 male resident reported resolved cough and 1 loose stool during the preceding 14 days. Virus was also detected in 2 of 62 staff (3.2%); both were symptomatic. One week later, resident SARS-CoV-2 testing was repeated and 1 new infection detected (asymptomatic). All residents remained in isolation and were clinically stable 14 days after the second test. Conclusions and Relevance: Detection of SARS-CoV-2 in asymptomatic residents highlights challenges in protecting older adults living in congregate settings. In this study, symptom screening failed to identify residents with infections and all 4 residents with SARS-CoV-2 remained asymptomatic after 14 days. Although 1 asymptomatic infection was found on retesting, a widespread facility outbreak was avoided. Compared with skilled nursing settings, in assisted/independent living communities, early surveillance to identify asymptomatic persons among residents and staff, in combination with adherence to recommended preventive strategies, may reduce viral spread.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can spread rapidly within skilled nursing facilities. After identification of a case of Covid-19 in a skilled nursing facility, we assessed transmission and evaluated the adequacy of symptom-based screening to identify infections in residents. METHODS: We conducted two serial point-prevalence surveys, 1 week apart, in which assenting residents of the facility underwent nasopharyngeal and oropharyngeal testing for SARS-CoV-2, including real-time reverse-transcriptase polymerase chain reaction (rRT-PCR), viral culture, and sequencing. Symptoms that had been present during the preceding 14 days were recorded. Asymptomatic residents who tested positive were reassessed 7 days later. Residents with SARS-CoV-2 infection were categorized as symptomatic with typical symptoms (fever, cough, or shortness of breath), symptomatic with only atypical symptoms, presymptomatic, or asymptomatic. RESULTS: Twenty-three days after the first positive test result in a resident at this skilled nursing facility, 57 of 89 residents (64%) tested positive for SARS-CoV-2. Among 76 residents who participated in point-prevalence surveys, 48 (63%) tested positive. Of these 48 residents, 27 (56%) were asymptomatic at the time of testing; 24 subsequently developed symptoms (median time to onset, 4 days). Samples from these 24 presymptomatic residents had a median rRT-PCR cycle threshold value of 23.1, and viable virus was recovered from 17 residents. As of April 3, of the 57 residents with SARS-CoV-2 infection, 11 had been hospitalized (3 in the intensive care unit) and 15 had died (mortality, 26%). Of the 34 residents whose specimens were sequenced, 27 (79%) had sequences that fit into two clusters with a difference of one nucleotide. CONCLUSIONS: Rapid and widespread transmission of SARS-CoV-2 was demonstrated in this skilled nursing facility. More than half of residents with positive test results were asymptomatic at the time of testing and most likely contributed to transmission. Infection-control strategies focused solely on symptomatic residents were not sufficient to prevent transmission after SARS-CoV-2 introduction into this facility.

We compared methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs) captured by culture-based surveillance and MRSA septicemia hospitalizations captured by administrative coding using statewide hospital discharge data in Connecticut from 2010 to 2018. Observed discrepancies between identification methods suggest administrative coding is inappropriate for assessing trends in MRSA BSIs.

BACKGROUND: Multidrug-resistant (MDR) bacteria that are commonly associated with health care cause a substantial health burden. Updated national estimates for this group of pathogens are needed to inform public health action. METHODS: Using data from patients hospitalized in a cohort of 890 U.S. hospitals during the period 2012-2017, we generated national case counts for both hospital-onset and community-onset infections caused by methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococcus (VRE), extended-spectrum cephalosporin resistance in Enterobacteriaceae suggestive of extended-spectrum beta-lactamase (ESBL) production, carbapenem-resistant Enterobacteriaceae, carbapenem-resistant acinetobacter species, and MDR Pseudomonas aeruginosa. RESULTS: The hospital cohort in the study accounted for 41.6 million hospitalizations (>20% of U.S. hospitalizations annually). The overall rate of clinical cultures was 292 cultures per 1000 patient-days and was stable throughout the time period. In 2017, these pathogens caused an estimated 622,390 infections (95% confidence interval [CI], 579,125 to 665,655) among hospitalized patients. Of these infections, 517,818 (83%) had their onset in the community, and 104,572 (17%) had their onset in the hospital. MRSA and ESBL infections accounted for the majority of the infections (52% and 32%, respectively). Between 2012 and 2017, the incidence decreased for MRSA infection (from 114.18 to 93.68 cases per 10,000 hospitalizations), VRE infection (from 24.15 to 15.76 per 10,000), carbapenem-resistant acinetobacter species infection (from 3.33 to 2.47 per 10,000), and MDR P. aeruginosa infection (from 13.10 to 9.43 per 10,000), with decreases ranging from -20.5% to -39.2%. The incidence of carbapenem-resistant Enterobacteriaceae infection did not change significantly (from 3.36 to 3.79 cases per 10,000 hospitalizations). The incidence of ESBL infection increased by 53.3% (from 37.55 to 57.12 cases per 10,000 hospitalizations), a change driven by an increase in community-onset cases. CONCLUSIONS: Health care-associated antimicrobial resistance places a substantial burden on patients in the United States. Further work is needed to identify improved interventions for both the inpatient and outpatient settings. (Funded by the Centers for Disease Control and Prevention.).

In the Seattle, Washington metropolitan area, where the first case of novel coronavirus 2019 disease (COVID-19) in the United States was reported (1), a community-level outbreak is ongoing with evidence of rapid spread and high morbidity and mortality among older adults in long-term care skilled nursing facilities (SNFs) (2,3). However, COVID-19 morbidity among residents of senior independent and assisted living communities, in which residents do not live as closely together as do residents in SNFs and do not require skilled nursing services, has not been described. During March 5-9, 2020, two residents of a senior independent and assisted living community in Seattle (facility 1) were hospitalized with confirmed COVID-19 infection; on March 6, social distancing and other preventive measures were implemented in the community. UW Medicine (the health system linked to the University of Washington), Public Health - Seattle & King County, and CDC conducted an investigation at the facility. On March 10, all residents and staff members at facility 1 were tested for SARS-CoV-2, the virus that causes COVID-19, and asked to complete a questionnaire about their symptoms; all residents were tested again 7 days later. Among 142 residents and staff members tested during the initial phase, three of 80 residents (3.8%) and two of 62 staff members (3.2%) had positive test results. The three residents had no symptoms at the time of testing, although one reported an earlier cough that had resolved. A fourth resident, who had negative test results in the initial phase, had positive test results 7 days later. This resident was asymptomatic on both days. Possible explanations for so few cases of COVID-19 in this residential community compared with those in several Seattle SNFs with high morbidity and mortality include more social distancing among residents and less contact with health care providers. In addition, early implementation of stringent isolation and protective measures after identification of two COVID-19 cases might have been effective in minimizing spread of the virus in this type of setting. When investigating a potential outbreak of COVID-19 in senior independent and assisted living communities, symptom screening is unlikely to be sufficient to identify all persons infected with SARS-CoV-2. Adherence to CDC guidance to prevent COVID-19 transmission in senior independent and assisted living communities (4) could be instrumental in preventing a facility outbreak.

Older adults are susceptible to severe coronavirus disease 2019 (COVID-19) outcomes as a consequence of their age and, in some cases, underlying health conditions (1). A COVID-19 outbreak in a long-term care skilled nursing facility (SNF) in King County, Washington that was first identified on February 28, 2020, highlighted the potential for rapid spread among residents of these types of facilities (2). On March 1, a health care provider at a second long-term care skilled nursing facility (facility A) in King County, Washington, had a positive test result for SARS-CoV-2, the novel coronavirus that causes COVID-19, after working while symptomatic on February 26 and 28. By March 6, seven residents of this second facility were symptomatic and had positive test results for SARS-CoV-2. On March 13, CDC performed symptom assessments and SARS-CoV-2 testing for 76 (93%) of the 82 facility A residents to evaluate the utility of symptom screening for identification of COVID-19 in SNF residents. Residents were categorized as asymptomatic or symptomatic at the time of testing, based on the absence or presence of fever, cough, shortness of breath, or other symptoms on the day of testing or during the preceding 14 days. Among 23 (30%) residents with positive test results, 10 (43%) had symptoms on the date of testing, and 13 (57%) were asymptomatic. Seven days after testing, 10 of these 13 previously asymptomatic residents had developed symptoms and were recategorized as presymptomatic at the time of testing. The reverse transcription-polymerase chain reaction (RT-PCR) testing cycle threshold (Ct) values indicated large quantities of viral RNA in asymptomatic, presymptomatic, and symptomatic residents, suggesting the potential for transmission regardless of symptoms. Symptom-based screening in SNFs could fail to identify approximately half of residents with COVID-19. Long-term care facilities should take proactive steps to prevent introduction of SARS-CoV-2 (3). Once a confirmed case is identified in an SNF, all residents should be placed on isolation precautions if possible (3), with considerations for extended use or reuse of personal protective equipment (PPE) as needed (4).

Importance: An important step in designing, executing, and evaluating cluster-randomized trials (CRTs) is understanding the correlation and thus nonindependence that exists among individuals in a cluster. In hospital epidemiology, there is a shortage of CRTs that have published their intraclass correlation coefficient or coefficient of variation (CV), making prospective sample size calculations difficult for investigators. Objectives: To estimate the number of hospitals needed to power parallel CRTs of interventions to reduce health care-associated infection outcomes and to demonstrate how different parameters such as CV and expected effect size are associated with the sample size estimates in practice. Design, Setting, and Participants: This longitudinal cohort study estimated parameters for sample size calculations using national rates developed by the Centers for Disease Control and Prevention for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, central-line-associated bloodstream infections (CLABSI), catheter-associated urinary tract infections (CAUTI), and Clostridium difficile infections (CDI) from 2016. For MRSA and vancomycin-resistant enterococci (VRE) acquisition, outcomes were estimated using data from 2012 from the Benefits of Universal Glove and Gown study. Data were collected from June 2017 through September 2018 and analyzed from September 2018 through January 2019. Main Outcomes and Measures: Calculated number of clusters needed for adequate power to detect an intervention effect using a 2-group parallel CRT. Results: To study an intervention with a 30% decrease in daily rates, 73 total clusters were needed (37 in the intervention group and 36 in the control group) for MRSA bacteremia, 82 for CAUTI, 60 for CLABSI, and 31 for CDI. If a 10% decrease in rates was expected, 768 clusters were needed for MRSA bacteremia, 875 for CAUTI, 631 for CLABSI, and 329 for CDI. For MRSA or VRE acquisition, 50 or 40 total clusters, respectively, were required to observe a 30% decrease, whereas 540 or 426 clusters, respectively, were required to detect a 10% decrease. Conclusions and Relevance: This study suggests that large sample sizes are needed to appropriately power parallel CRTs targeting infection prevention outcomes. Sample sizes are most associated with expected effect size and CV of hospital rates.

OBJECTIVE: To compare risk of surgical site infection (SSI) following cesarean delivery between women covered by Medicaid and private health insurance. STUDY DESIGN: Retrospective cohort. STUDY POPULATION: Cesarean deliveries covered by Medicaid or private insurance and reported to the National Healthcare Safety Network (NHSN) and state inpatient discharge databases by hospitals in California (2011-2013). METHODS: Deliveries reported to NHSN and state inpatient discharge databases were linked to identify SSIs in the 30 days following cesarean delivery, primary payer, and patient and procedure characteristics. Additional hospital-level characteristics were obtained from public databases. Relative risk of SSI by primary payer primary payer was assessed using multivariable logistic regression adjusting for patient, procedure, and hospital characteristics, accounting for facility-level clustering. RESULTS: Of 291,757 cesarean deliveries included, 48% were covered by Medicaid. SSIs were detected following 1,055 deliveries covered by Medicaid (0.75%) and 955 deliveries covered by private insurance (0.63%) (unadjusted odds ratio, 1.2; 95% confidence interval [CI], 1.1-1.3; P &lt; .0001). The adjusted odds of SSI following cesarean deliveries covered by Medicaid was 1.4 (95% CI, 1.2-1.6; P &lt; .0001) times the odds of those covered by private insurance. CONCLUSIONS: In this, the largest and only multicenter study to investigate SSI risk following cesarean delivery by primary payer, Medicaid-insured women had a higher risk of infection than privately insured women. These findings suggest the need to evaluate and better characterize the quality of maternal healthcare for and needs of women covered by Medicaid to inform targeted infection prevention and policy.

INTRODUCTION: By 2007, all Department of Veterans Affairs medical centers (VAMCs) had initiated a multifaceted methicillin-resistant Staphylococcus aureus (MRSA) prevention program. MRSA and methicillin-susceptible S. aureus (MSSA) infection rates among VAMC inpatients from 2005 to 2017 were assessed. METHODS: Clinical microbiology data from any patient admitted to an acute-care VAMC in the United States from 2005 through 2017 and trends in hospital-acquired MRSA colonization were examined. RESULTS: S. aureus infections decreased by 43% overall during the study period (p<0.001), driven primarily by decreases in MRSA, which decreased by 55% (p<0.001), whereas MSSA decreased by 12% (p = 0.003). Hospital-onset MRSA and MSSA infections decreased by 66% (p<0.001) and 19% (p = 0.02), respectively. Community-onset MRSA infections decreased by 41% (p<0.001), whereas MSSA infections showed no significant decline. Acquisition of MRSA colonization decreased 78% during 2008-2017 (17% annually, p<0.001). MRSA infection rates declined more sharply among patients who had negative admission surveillance MRSA screening tests (annual 9.7% decline) compared with those among patients with positive admission MRSA screening tests (4.2%) (p<0.05). CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Significant reductions in S. aureus infection following the VAMC intervention were led primarily by decreases in MRSA. Moreover, MRSA infection declines were much larger among patients not carrying MRSA at the time of admission than among those who were. Taken together, these results suggest that decreased MRSA transmission played a substantial role in reducing overall S. aureus infections at VAMCs. Recent calls to withdraw infection control interventions designed to prevent MRSA transmission might be premature and inadvisable, at least until more is known about effective control of bacterial pathogen transmission in health care settings. Effective S. aureus prevention strategies require a multifaceted approach that includes adherence to current CDC recommendations for preventing not only device- and procedure-associated infections, but also transmission of health care-prevalent strains.

BACKGROUND: Unnecessary antibiotic use (AU) contributes to increased rates of Clostridioides difficile Infection (CDI). The impact of antibiotic restriction on hospital-onset CDI (HO-CDI) has not been assessed in a large group of U.S. acute care hospitals (ACHs). METHODS: We examined cross-sectional and temporal associations between rates of hospital-level AU and HO-CDI using data from 549 ACHs. HO-CDI, a discharge with a secondary ICD-9-CM for CDI (008.45) and treatment with metronidazole or oral vancomycin >/= 3 days after admission. Analyses were performed using multivariable generalized estimating equation models adjusting for patient and hospital characteristics. RESULTS: During 2006-2012, the unadjusted annual rates of HO-CDI and total AU were 7.3 per 10,000 patient-days (PD) (95% CI: 7.1-7.5) and 811 days of therapy (DOT)/1,000 PD (95% CI: 803-820), respectively. In the cross-sectional analysis, for every 50 DOT/1,000 PD increase in total AU, there was a 4.4% increase in HO-CDI. For every 10 DOT/1,000 PD increase in use of third- and fourth-generation cephalosporins or carbapenems there was a 2.1% and 2.9% increase in HO-CDI, respectively. In the time-series analysis, the 6 ACHs with a >/= 30% decrease in total AU had a 33% decrease in HO-CDI (rate ratio, 0.67; 95% CI, 0.47-0.96); ACHs with a >/= 20% decrease in fluoroquinolone or third- and fourth-generation cephalosporin use had a corresponding decrease in HO-CDI of 8% and 13%, respectively. CONCLUSIONS: At an ecologic level, reductions in total AU, use of fluoroquinolones and third- and fourth-generation cephalosporins were each associated with decreased HO-CDI rates.