Genomic Analysis of Clostridioides difficile in 2 Regions of the United States Reveals a Diversity of Strains and Limited Transmission.

BACKGROUND: The distribution of Clostridioides difficile strains and transmission dynamics in the United States are not well defined. Whole-genome sequencing across 2 Centers for Disease Control and Prevention Emerging Infections Program C. difficile infection (CDI) surveillance regions (Minnesota and New York) was performed to identify predominant multilocus sequence types (MLSTs) in community-associated (CA) and healthcare-associated (HCA) disease and assess transmission. METHODS: Whole-genome sequencing was performed on C. difficile isolates from patients with CDI over 3 months between 2016 and 2017. Patients were residents of the catchment area without a positive C. difficile test in the preceding 8 weeks. CDI cases were epidemiologically classified as HCA or CA. RESULTS: Of 422 isolates, 212 (50.2%) were HCA and 203 (48.1%) were CA. Predominant MLSTs were sequence type (ST) 42 (9.3%), ST8 (7.8%), and ST2 (8.1%). MLSTs associated with HCA-CDI included ST1 (76%), ST53 (83.3%), and ST43 (80.0%), while those associated with CA-CDI included ST3 (76.9%) and ST41 (77.8%). ST1 was more frequent in New York than in Minnesota (10.8% vs 3.1%). Thirty-three pairs were closely related genomically, 14 of which had potential patient-to-patient transmission supported by record review. CONCLUSIONS: The genomic epidemiology of C. difficile across 2 regions of the United States indicates the presence of a diverse strain profile and limited direct transmission.

Outbreak of COVID-19 among children and young adults in a cancer centre daycare unit.

Nosocomial transmission of COVID-19 among immunocompromised hosts can have a serious impact on COVID-19 severity, underlying disease progression and SARS-CoV-2 transmission to other patients and healthcare workers within hospitals. We experienced a nosocomial outbreak of COVID-19 in the setting of a daycare unit for paediatric and young adult cancer patients. Between 9 and 18 November 2020, 473 individuals (181 patients, 247 caregivers/siblings and 45 staff members) were exposed to the index case, who was a nursing staff. Among them, three patients and four caregivers were infected. Two 5-year-old cancer patients with COVID-19 were not severely ill, but a 25-year-old cancer patient showed prolonged shedding of SARS-CoV-2 RNA for at least 12 weeks, which probably infected his mother at home approximately 7-8 weeks after the initial diagnosis. Except for this case, no secondary transmission was observed from the confirmed cases in either the hospital or the community. To conclude, in the day care setting of immunocompromised children and young adults, the rate of in-hospital transmission of SARS-CoV-2 was 1.6% when applying the stringent policy of infection prevention and control, including universal mask application and rapid and extensive contact investigation. Severely immunocompromised children/young adults with COVID-19 would have to be carefully managed after the mandatory isolation period while keeping the possibility of prolonged shedding of live virus in mind.

CSC Expert Consensus on Principles of Clinical Management of Patients With Severe Emergent Cardiovascular Diseases During the COVID-19 Epidemic.

In response to the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, the Chinese Society of Cardiology (CSC) issued this consensus statement after consulting with 125 medical experts in the fields of cardiovascular disease and infectious disease. The over-arching principles laid out here are the following: 1) Consider the prevention and control of COVID-19 transmission as the highest priority, including self-protection of medical staff; 2) Patient risk assessment of both infection and cardiovascular issues. Where appropriate, preferential use of conservative medical therapeutic approaches to minimize disease spread; 3) At all times, medical practices and interventional procedures should be conducted in accordance with the directives of the infection control department of local hospitals and local health commissions.

Transmission of community- and hospital-acquired SARS-CoV-2 in hospital settings in the UK: A cohort study.

BACKGROUND: Nosocomial spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been widely reported, but the transmission pathways among patients and healthcare workers (HCWs) are unclear. Identifying the risk factors and drivers for these nosocomial transmissions is critical for infection prevention and control interventions. The main aim of our study was to quantify the relative importance of different transmission pathways of SARS-CoV-2 in the hospital setting. METHODS AND FINDINGS: This is an observational cohort study using data from 4 teaching hospitals in Oxfordshire, United Kingdom, from January to October 2020. Associations between infectious SARS-CoV-2 individuals and infection risk were quantified using logistic, generalised additive and linear mixed models. Cases were classified as community- or hospital-acquired using likely incubation periods of 3 to 7 days. Of 66,184 patients who were hospitalised during the study period, 920 had a positive SARS-CoV-2 PCR test within the same period (1.4%). The mean age was 67.9 (±20.7) years, 49.2% were females, and 68.5% were from the white ethnic group. Out of these, 571 patients had their first positive PCR tests while hospitalised (62.1%), and 97 of these occurred at least 7 days after admission (10.5%). Among the 5,596 HCWs, 615 (11.0%) tested positive during the study period using PCR or serological tests. The mean age was 39.5 (±11.1) years, 78.9% were females, and 49.8% were nurses. For susceptible patients, 1 day in the same ward with another patient with hospital-acquired SARS-CoV-2 was associated with an additional 7.5 infections per 1,000 susceptible patients (95% credible interval (CrI) 5.5 to 9.5/1,000 susceptible patients/day) per day. Exposure to an infectious patient with community-acquired Coronavirus Disease 2019 (COVID-19) or to an infectious HCW was associated with substantially lower infection risks (2.0/1,000 susceptible patients/day, 95% CrI 1.6 to 2.2). As for HCW infections, exposure to an infectious patient with hospital-acquired SARS-CoV-2 or to an infectious HCW were both associated with an additional 0.8 infection per 1,000 susceptible HCWs per day (95% CrI 0.3 to 1.6 and 0.6 to 1.0, respectively). Exposure to an infectious patient with community-acquired SARS-CoV-2 was associated with less than half this risk (0.2/1,000 susceptible HCWs/day, 95% CrI 0.2 to 0.2). These assumptions were tested in sensitivity analysis, which showed broadly similar results. The main limitations were that the symptom onset dates and HCW absence days were not available. CONCLUSIONS: In this study, we observed that exposure to patients with hospital-acquired SARS-CoV-2 is associated with a substantial infection risk to both HCWs and other hospitalised patients. Infection control measures to limit nosocomial transmission must be optimised to protect both staff and patients from SARS-CoV-2 infection.

Community-Associated Outbreak of COVID-19 in a Correctional Facility - Utah, September 2020-January 2021.

Transmission of SARS-CoV-2, the virus that causes COVID-19, is common in congregate settings such as correctional and detention facilities (1-3). On September 17, 2020, a Utah correctional facility (facility A) received a report of laboratory-confirmed SARS-CoV-2 infection in a dental health care provider (DHCP) who had treated incarcerated persons at facility A on September 14, 2020 while asymptomatic. On September 21, 2020, the roommate of an incarcerated person who had received dental treatment experienced COVID-19-compatible symptoms*; both were housed in block 1 of facility A (one of 16 occupied blocks across eight residential units). Two days later, the roommate received a positive SARS-CoV-2 test result, becoming the first person with a known-associated case of COVID-19 at facility A. During September 23-24, 2020, screening of 10 incarcerated persons who had received treatment from the DHCP identified another two persons with COVID-19, prompting isolation of all three patients in an unoccupied block at the facility. Within block 1, group activities were stopped to limit interaction among staff members and incarcerated persons and prevent further spread. During September 14-24, 2020, six facility A staff members, one of whom had previous close contact† with one of the patients, also reported symptoms. On September 27, 2020, an outbreak was confirmed after specimens from all remaining incarcerated persons in block 1 were tested; an additional 46 cases of COVID-19 were identified, which were reported to the Salt Lake County Health Department and the Utah Department of Health. On September 30, 2020, CDC, in collaboration with both health departments and the correctional facility, initiated an investigation to identify factors associated with the outbreak and implement control measures. As of January 31, 2021, a total of 1,368 cases among 2,632 incarcerated persons (attack rate = 52%) and 88 cases among 550 staff members (attack rate = 16%) were reported in facility A. Among 33 hospitalized incarcerated persons, 11 died. Quarantine and monitoring of potentially exposed persons and implementation of available prevention measures, including vaccination, are important in preventing introduction and spread of SARS-CoV-2 in correctional facilities and other congregate settings (4).

Quantifying the roles of vomiting, diarrhea, and residents vs. staff in norovirus transmission in U.S. nursing home outbreaks.

The role of individual case characteristics, such as symptoms or demographics, in norovirus transmissibility is poorly understood. Six nursing home norovirus outbreaks occurring in South Carolina, U.S. from 2014 to 2016 were examined. We aimed to quantify the contribution of symptoms and other case characteristics in norovirus transmission using the reproduction number (REi) as an estimate of individual case infectivity and to examine how transmission changes over the course of an outbreak. Individual estimates of REi were calculated using a maximum likelihood procedure to infer the average number of secondary cases generated by each case. The associations between case characteristics and REi were estimated using a weighted multivariate mixed linear model. Outbreaks began with one to three index case(s) with large estimated REi's (range: 1.48 to 8.70) relative to subsequent cases. Of the 209 cases, 155 (75%) vomited, 164 (79%) had diarrhea, and 158 (76%) were nursing home residents (vs. staff). Cases who vomited infected 2.12 (95% CI: 1.68, 2.68) times the number of individuals as non-vomiters, cases with diarrhea infected 1.39 (95% CI: 1.03, 1.87) times the number of individuals as cases without diarrhea, and resident-cases infected 1.53 (95% CI: 1.15, 2.02) times the number of individuals as staff-cases. Index cases tended to be residents (vs. staff) who vomited and infected considerably more secondary cases compared to non-index cases. Results suggest that individuals, particularly residents, who vomit are more infectious and tend to drive norovirus transmission in U.S. nursing home norovirus outbreaks. While diarrhea also plays a role in norovirus transmission, it is to a lesser degree than vomiting in these settings. Results lend support for prevention and control measures that focus on cases who vomit, particularly if those cases are residents.

Patient Perceptions on Barriers and Facilitators to Accessing Low-acuity Surgery During COVID-19 Pandemic.

BACKGROUND: The onset of the COVID-19 pandemic led to the postponement of low-acuity surgical procedures in an effort to conserve resources and ensure patient safety. This study aimed to characterize patient-reported concerns about undergoing surgical procedures during the pandemic. METHODS: We administered a cross-sectional survey to patients who had their general and plastic surgical procedures postponed at the onset of the pandemic, asking about barriers to accessing surgical care. Questions addressed dependent care, transportation, employment and insurance status, as well as perceptions of and concerns about COVID-19. Mixed methods and inductive thematic analyses were conducted. RESULTS: One hundred thirty-five patients were interviewed. We identified the following patient concerns: contracting COVID-19 in the hospital (46%), being alone during hospitalization (40%), facing financial stressors (29%), organizing transportation (28%), experiencing changes to health insurance coverage (25%), and arranging care for dependents (18%). Nonwhite participants were 5 and 2.5 times more likely to have concerns about childcare and transportation, respectively. Perceptions of decreased hospital safety and the consequences of possible COVID-19 infection led to delay in rescheduling. Education about safety measures and communication about scheduling partially mitigated concerns about COVID-19. However, uncertainty about timeline for rescheduling and resolution of the pandemic contributed to ongoing concerns. CONCLUSIONS: Providing effective surgical care during this unprecedented time requires both awareness of societal shifts impacting surgical patients and system-level change to address new barriers to care. Eliciting patients' perspectives, adapting processes to address potential barriers, and effectively educating patients about institutional measures to minimize in-hospital transmission of COVID-19 should be integrated into surgical care.

Factors preventing SARS-CoV-2 transmission during unintentional exposure in a GP practice: a cohort study of patient contacts; Germany, 2020.

Two general practitioners (GPs) with SARS-CoV-2 infection provided in-person patient care to patients of their joint medical practice before and after symptom onset, up until SARS-CoV-2 laboratory confirmation. Through active contact tracing, the local public health authorities recruited the cohort of patients that had contact with either GP in their putative infectious period. In this cohort of patient contacts, we assess the frequency and determinants of SARS-CoV-2-transmission from GPs to patients. We calculated incidence rate ratios (IRR) to explore the type of contact as an explanatory variable for COVID-19 cases. Among the cohort of 83 patient contacts, we identified 22 (27%) COVID-19 cases including 17 (21%) possible, three (4%) probable and two (2%) confirmed cases. All 22 cases had contact with a GP when the GP did not wear a mask, and/or when contact was ≥10 min. Importantly, patients who had contact <10 min with a GP wearing a facemask were at reduced risk (IRR 0.21; 95% CI 0.01-0.99) of COVID-19. This outbreak investigation adds to the body of evidence in supporting current guidelines on measures at preventing the transmission of SARS-CoV-2 in an outpatient setting.

Results of a national web-based survey on the SARS-CoV-2 infectious state of otorhinolaryngologists in Germany.

PURPOSE: SARS-CoV-2 is detected on the mucosa of the upper airways to a high degree. In the course of the COVID-19 pandemic, otorhinolaryngologists (ORL) are assumed to be at high risk due to close contact with the mucosa of the upper airways. No data are yet available providing evidence that ORLs have an increased risk of infection. METHODS: German ORLs were invited via e-mail through the German Society of ORL, Head and Neck Surgery and the German ENT Association to participate in a web-based survey about infection with SARS-CoV-2 and development of COVID-19. Data of infections and concomitant parameters in German ORLs were collected and compared to the total number of infections in Germany. RESULTS: Out of 6383 German ORLs, 970 (15%) participated. 54 ORLs reported testing positive for SARS-CoV-2. Compared to the total population of Germany, ORLs have a relative risk of 3.67 (95% CI 2.82; 4.79) of contracting SARS-CoV-2. Domestic quarantine was conducted in 96.3% of cases. Two individuals were admitted to hospital without intensive care. No casualties were reported. In 31 cases, the source of infection was not identifiable whereas 23 had a clear medical aetiology: infected patients: n = 5, 9.26%; medical staff: n = 13, 14.1%. 9.26% (n = 5) of the identified cases were related to contact to infected family members (n = 3), closer neighbourhood (n = 1) or general public (n = 1). There was no identified increased risk of infection due to performing surgery. CONCLUSION: German ORLs have an almost 3.7-fold risk of contracting SARS-CoV-2 compared to the population baseline level. Appropriate protection appears to be necessary for this occupational group.

Outcomes of elective head and neck confirmed or suspected cancer surgery during the COVID-19 pandemic.

PURPOSE: To analyse the complication outcomes of COVID-19 negative patients undergoing elective head and neck surgery during the COVID-19 pandemic. METHODS: This was a retrospective case review of all patients undergoing elective head and neck surgery for confirmed or suspected head and neck cancer. RESULTS: There were no mortalities recorded in the cohort of patients analysed. At 30 days, pulmonary complications had occurred in 4 patients (9%). None of these were related to COVID infection. CONCLUSION: With careful pre-operative screening of patients for COVID-19 and post-operative care in a COVID-19 clean ward, head and neck surgery can proceed safely during the epidemic. This data could help to minimise delay in treatment by allowing a greater number of elective head and neck cancer operations to proceed.

COVID-19 pandemic: an Italian single institution's experience and lessons learned by public health residents' workforce.

Methods: We hereby provide a systematic description of the response actions in which the public health residents' workforce was pivotal, in a large tertiary hospital. Background: The Coronavirus Disease 2019 pandemic has posed incredible challenges to healthcare workers worldwide. The residents have been affected by an almost complete upheaval of the previous setting of activities, with a near total focus on service during the peak of the emergency. In our Institution, residents in public health were extensively involved in leading activities in the management of Coronavirus Disease 2019 pandemic. Results: The key role played by residents in the response to Coronavirus Disease 2019 pandemic is highlighted by the diversity of contributions provided, from cooperation in the rearrangement of hospital paths for continuity of care, to establishing and running new services to support healthcare professionals. Overall, they constituted a workforce that turned essential in governing efficiently such a complex scenario. Conclusions: Despite the difficulties posed by the contingency and the sacrifice of many training activities, Coronavirus Disease 2019 pandemic turned out to be a unique opportunity of learning and measuring one's capabilities and limits in a context of absolute novelty and uncertainty.

Prehospital Triage of Acute Stroke Patients During the COVID-19 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic has broad implications on stroke patient triage. Emergency medical services providers have to ensure timely transfer of patients while minimizing the risk of infectious exposure for themselves, their co-workers, and other patients. This statement paper provides a conceptual framework for acute stroke patient triage and transfer during the COVID-19 pandemic and similar healthcare emergencies in the future.

Improving Stroke Care in Times of the COVID-19 Pandemic Through Simulation: Practice Your Protocols!

During the coronavirus disease 2019 (COVID-19) pandemic, infectious disease control is of utmost importance in acute stroke treatment. This is a new situation for most stroke teams that often leads to uncertainty among physicians, nurses, and technicians who are in immediate contact with patients. The situation is made even more complicated by numerous new regulations and protocols that are released in rapid succession. Herein, we are describing our experience with simulation training for COVID-19 stroke treatment protocols. One week of simulation training allowed us to identify numerous latent safety threats and to adjust our institution-specific protocols to mitigate them. It also helped our physicians and nurses to practice relevant tasks and behavioral patterns (eg, proper donning and doffing PPE, where to dispose potentially contaminated equipment) to minimize their infectious exposure and to adapt to the new situation. We therefore strongly encourage other hospitals to adopt simulation training to prepare their medical teams for code strokes during the COVID-19 pandemic.

Absence of COVID-19 Infection in Patients Accessing IBD Unit at Humanitas, Milan: Implications for Postlockdown Measures.

INTRODUCTION: The risk of coronavirus disease-19 infection for healthcare professionals and patients in hospitals remains unclear. METHODS: We investigated whether precautions adopted in our inflammatory bowel disease (IBD) unit have minimized the risks of infection for all patients accessing our facilities in a 1-month period by assessing the rate of coronavirus disease-19 infection in the follow-up period. RESULTS: Three hundred-twenty patients with IBD were included. None were infected from severe acute respiratory syndrome-coronavirus 2 in the follow-up period. None of the IBD team members were infected. DISCUSSION: Neither pharmacological immunosuppression nor access to the hospital seem to be risk factors for infection in patients with IBD.

American Neurogastroenterology and Motility Society Task Force Recommendations for Resumption of Motility Laboratory Operations During the COVID-19 Pandemic.

The American Neurogastroenterology and Motility Society Task Force recommends that gastrointestinal motility procedures should be performed in motility laboratories adhering to the strict recommendations and personal protective equipment (PPE) measures to protect patients, ancillary staff, and motility allied health professionals. When available and within constraints of institutional guidelines, it is preferable for patients scheduled for motility procedures to complete a coronavirus disease 2019 (COVID-19) test within 48 hours before their procedure, similar to the recommendations before endoscopy made by gastroenterology societies. COVID-19 test results must be documented before performing procedures. If procedures are to be performed without a COVID-19 test, full PPE use is recommended, along with all social distancing and infection control measures. Because patients with suspected motility disorders may require multiple procedures, sequential scheduling of procedures should be considered to minimize need for repeat COVID-19 testing. The strategies for and timing of procedure(s) should be adapted, taking into consideration local institutional standards, with the provision for screening without testing in low prevalence areas. If tested positive for COVID-19, subsequent negative testing may be required before scheduling a motility procedure (timing is variable). Specific recommendations for each motility procedure including triaging, indications, PPE use, and alternatives to motility procedures are detailed in the document. These recommendations may evolve as understanding of virus transmission and prevalence of COVID-19 infection in the community changes over the upcoming months.

Managing patient flows in radiation oncology during the COVID-19 pandemic : Reworking existing treatment designs to prevent infections at a German hot spot area University Hospital.

PURPOSE: The described work aimed to avoid cancellations of indispensable treatments by implementing active patient flow management practices and optimizing infrastructure utilization in the radiation oncology department of a large university hospital and regional COVID-19 treatment center close to the first German SARS-CoV­2 hotspot region Heinsberg in order to prevent nosocomial infections in patients and personnel during the pandemic. PATIENTS AND METHODS: The study comprised year-to-date intervention analyses of in- and outpatient key procedures, machine occupancy, and no-show rates in calendar weeks 12 to 19 of 2019 and 2020 to evaluate effects of active patient flow management while monitoring nosocomial COVID-19 infections. RESULTS: Active patient flow management helped to maintain first-visit appointment compliance above 85.5%. A slight appointment reduction of 10.3% daily (p = 0.004) could still significantly increase downstream planning CT scheduling (p = 0.00001) and performance (p = 0.0001), resulting in an absolute 20.1% (p = 0.009) increment of CT performance while avoiding overbooking practices. Daily treatment start was significantly increased by an absolute value of 18.5% (p = 0.026). Hypofractionation and acceleration were significantly increased (p = 0.0043). Integrating strict testing guidelines, a distancing regimen for staff and patients, hygiene regulations, and precise appointment scheduling, no SARS-CoV­2 infection in 164 tested radiation oncology service inpatients was observed. CONCLUSION: In times of reduced medical infrastructure capacities and resources, controlling infrastructural time per patient as well as optimizing facility utilization and personnel workload during treatment evaluation, planning, and irradiation can help to improve appointment compliance and quality management. Avoiding recurrent and preventable exposure to healthcare infrastructure has potential health benefits and might avert cross infections during the pandemic. Active patient flow management in high-risk COVID-19 regions can help Radiation Oncologists to continue and initiate treatments safely, instead of cancelling and deferring indicated therapies.

ESGE and ESGENA Position Statement on gastrointestinal endoscopy and the COVID-19 pandemic.

We are currently living in the throes of the COVID-19 pandemic that imposes a significant stress on health care providers and facilities. Europe is severely affected with an exponential increase in incident infections and deaths. The clinical manifestations of COVID-19 can be subtle, encompassing a broad spectrum from asymptomatic mild disease to severe respiratory illness. Health care professionals in endoscopy units are at increased risk of infection from COVID-19. Infection prevention and control has been shown to be dramatically effective in assuring the safety of both health care professionals and patients. The European Society of Gastrointestinal Endoscopy (www.esge.com) and the European Society of Gastroenterology and Endoscopy Nurses and Associates (www.esgena.org) are joining forces to provide guidance during this pandemic to help assure the highest level of endoscopy care and protection against COVID-19 for both patients and endoscopy unit personnel. This guidance is based upon the best available evidence regarding assessment of risk during the current status of the pandemic and a consensus on which procedures to perform and the priorities on resumption. We appreciate the gaps in knowledge and evidence, especially on the proper strategy(ies) for the resumption of normal endoscopy practice during the upcoming phases and end of the pandemic and therefore a list of potential research questions is presented. New evidence may result in an updated statement.

Seroprevalence of SARS-CoV-2 Among Frontline Health Care Personnel in a Multistate Hospital Network - 13 Academic Medical Centers, April-June 2020.

Health care personnel (HCP) caring for patients with coronavirus disease 2019 (COVID-19) might be at high risk for contracting SARS-CoV-2, the virus that causes COVID-19. Understanding the prevalence of and factors associated with SARS-CoV-2 infection among frontline HCP who care for COVID-19 patients are important for protecting both HCP and their patients. During April 3-June 19, 2020, serum specimens were collected from a convenience sample of frontline HCP who worked with COVID-19 patients at 13 geographically diverse academic medical centers in the United States, and specimens were tested for antibodies to SARS-CoV-2. Participants were asked about potential symptoms of COVID-19 experienced since February 1, 2020, previous testing for acute SARS-CoV-2 infection, and their use of personal protective equipment (PPE) in the past week. Among 3,248 participants, 194 (6.0%) had positive test results for SARS-CoV-2 antibodies. Seroprevalence by hospital ranged from 0.8% to 31.2% (median = 3.6%). Among the 194 seropositive participants, 56 (29%) reported no symptoms since February 1, 2020, 86 (44%) did not believe that they previously had COVID-19, and 133 (69%) did not report a previous COVID-19 diagnosis. Seroprevalence was lower among personnel who reported always wearing a face covering (defined in this study as a surgical mask, N95 respirator, or powered air purifying respirator [PAPR]) while caring for patients (5.6%), compared with that among those who did not (9.0%) (p = 0.012). Consistent with persons in the general population with SARS-CoV-2 infection, many frontline HCP with SARS-CoV-2 infection might be asymptomatic or minimally symptomatic during infection, and infection might be unrecognized. Enhanced screening, including frequent testing of frontline HCP, and universal use of face coverings in hospitals are two strategies that could reduce SARS-CoV-2 transmission.

Facility-Wide Testing for SARS-CoV-2 in Nursing Homes - Seven U.S. Jurisdictions, March-June 2020.

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.