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Context: Methicillin-resistant Staphylococcus aureus (MRSA) has traditionally been considered a health care-associated pathogen in patients with established risk factors. However, MRSA has emerged in patients without established risk factors (community-associated MRSA).Objective: To characterize epidemiological and microbiological characteristics of community-associated MRSA cases compared with health care-associated MRSA cases.Design, Setting, and Patients: Prospective cohort study of patients with MRSA infection identified at 12 Minnesota laboratory facilities from January 1 through December 31, 2000, comparing community-associated (median age, 23 years) with health care-associated (median age, 68 years) MRSA cases.Main Outcome Measures: Clinical infections associated with either community-associated or health care-associated MRSA, microbiological characteristics of the MRSA isolates including susceptibility testing, pulsed-field gel electrophoresis, and staphylococcal exotoxin gene testing.Results: Of 1100 MRSA infections, 131 (12%) were community-associated and 937 (85%) were health care-associated; 32 (3%) could not be classified due to lack of information. Skin and soft tissue infections were more common among community-associated cases (75%) than among health care-associated cases (37%) (odds ratio [OR], 4.25; 95% confidence interval [CI], 2.97-5.90). Although community-associated MRSA isolates were more likely to be susceptible to 4 antimicrobial classes (adjusted OR, 2.44; 95% CI, 1.35-3.86), most community-associated infections were initially treated with antimicrobials to which the isolate was nonsusceptible. Community-associated isolates were also more likely to belong to 1 of 2 pulsed-field gel electrophoresis clonal groups in both univariate and multivariate analysis. Community-associated isolates typically possessed different exotoxin gene profiles (eg, Panton Valentine leukocidin genes) compared with health care-associated isolates.Conclusions: Community-associated and health care-associated MRSA cases differ demographically and clinically, and their respective isolates are microbiologically distinct. This suggests that most community-associated MRSA strains did not originate in health care settings, and that their microbiological features may have contributed to their emergence in the community. Clinicians should be aware that therapy with beta-lactam antimicrobials can no longer be relied on as the sole empiric therapy for severely ill outpatients whose infections may be staphylococcal in origin. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 transmission dynamics within households involving children are complex. We examined the association between paediatric index case (PIC) age and subsequent household SARS-CoV-2 transmission among cases reported to the Minnesota Department of Health between March 2021 and February 2022. In our primary analysis, we used logistic regression to estimate odds ratios adjusted for race/ethnicity, sex, geographic region, and disease severity among households with an unvaccinated PIC. We performed a secondary analysis among households where the PIC was eligible for vaccination adjusting for the same covariates plus time since the last vaccination. Both analyses were stratified by variant wave. During the Alpha wave, PICs of all age groups had similar odds of subsequent transmission. During Delta and Omicron waves, PICs aged 16-17 had higher odds of subsequent transmission than PICs aged 0-4 (Delta OR, 1.32; [95% CI, 1.16-1.51], Omicron OR, 4.21; [95% CI, 3.25-5.45]). In the secondary analysis, unvaccinated PICs had higher odds of subsequent transmission than vaccinated PICs (Delta OR 2.89 [95% CI, 2.18-3.84], Omicron OR 1.35 [95% CI, 1.21-1.50]). Enhanced preventative measures, especially for 12-17-year-olds, may limit SARS-CoV-2 transmission within households involving children.

Importance: Respiratory syncytial virus (RSV) infection can cause severe illness in adults. However, there is considerable uncertainty in the burden of RSV-associated hospitalizations among adults prior to RSV vaccine introduction., Objective: To describe the demographic characteristics of adults hospitalized with laboratory-confirmed RSV and to estimate annual rates and numbers of RSV-associated hospitalizations, intensive care unit (ICU) admissions, and in-hospital deaths., Design, Setting, and Participants: This cross-sectional study used data from the RSV Hospitalization Surveillance Network (RSV-NET), a population-based surveillance platform that captures RSV-associated hospitalizations in 58 counties in 12 states, covering approximately 8% of the US population. The study period spanned 7 surveillance seasons from 2016-2017 through 2022-2023. Included cases from RSV-NET were nonpregnant hospitalized adults aged 18 years or older residing in the surveillance catchment area and with a positive RSV test result., Exposure: Laboratory-confirmed RSV-associated hospitalization, defined as a positive RSV test result within 14 days before or during hospitalization., Main Outcomes and Measures: Hospitalization rates per 100 000 adult population, stratified by age group. After adjusting for test sensitivity and undertesting for RSV in adults hospitalized with acute respiratory illnesses, rates were extrapolated to the US population to estimate annual numbers of RSV-associated hospitalizations. Clinical outcome data were used to estimate RSV-associated ICU admissions and in-hospital deaths., Results: From the 2016 to 2017 through the 2022 to 2023 RSV seasons, there were 16 575 RSV-associated hospitalizations in adults (median [IQR] age, 70 [58-81] years; 9641 females [58.2%]). Excluding the 2020 to 2021 and the 2021 to 2022 seasons, when the COVID-19 pandemic affected RSV circulation, hospitalization rates ranged from 48.9 (95% CI, 33.4-91.5) per 100 000 adults in 2016 to 2017 to 76.2 (95% CI, 55.2-122.7) per 100 000 adults in 2017 to 2018. Rates were lowest among adults aged 18 to 49 years (8.6 [95% CI, 5.7-16.8] per 100 000 adults in 2016-2017 to 13.1 [95% CI, 11.0-16.1] per 100 000 adults in 2022-2023) and highest among adults 75 years or older (244.7 [95% CI, 207.9-297.3] per 100 000 adults in 2022-2023 to 411.4 [95% CI, 292.1-695.4] per 100 000 adults in 2017-2018). Annual hospitalization estimates ranged from 123 000 (95% CI, 84 000-230 000) in 2016 to 2017 to 193 000 (95% CI, 140 000-311 000) in 2017 to 2018. Annual ICU admission estimates ranged from 24 400 (95% CI, 16 700-44 800) to 34 900 (95% CI, 25 500-55 600) for the same seasons. Estimated annual in-hospital deaths ranged from 4680 (95% CI, 3570-6820) in 2018 to 2019 to 8620 (95% CI, 6220-14 090) in 2017 to 2018. Adults 75 years or older accounted for 45.6% (range, 43.1%-48.8%) of all RSV-associated hospitalizations, 38.6% (range, 36.7%-41.0%) of all ICU admissions, and 58.7% (range, 51.9%-67.1%) of all in-hospital deaths., Conclusions and Relevance: In this cross-sectional study of adults hospitalized with RSV before the 2023 introduction of RSV vaccines, RSV was associated with substantial burden of hospitalizations, ICU admissions, and in-hospital deaths in adults, with the highest rates occurring in adults 75 years or older. Increasing RSV vaccination of older adults has the potential to reduce associated hospitalizations and severe clinical outcomes.

Background: Screening for SARS-CoV-2 infection among hospital admissions made interpretation of COVID-19 hospitalization data challenging as SARS-CoV-2-positive persons with mild or asymptomatic infection may be incorrectly identified as COVID-19-associated hospitalizations. The study objective is to estimate the proportion of hospitalizations likely attributable to COVID-19 among SARS-CoV-2-positive hospitalized patients., Methods: A sample of laboratory-confirmed SARS-CoV-2-positive hospitalizations from the COVID-19-Associated Hospitalization Surveillance Network (COVID-NET) from June 2020 to September 2023 was analyzed, with a focus on July 2022 to September 2023. Likely COVID-19-attributable hospitalizations were defined as hospitalizations among SARS-CoV-2-positive non-pregnant adults ages ≥ 18 years with COVID-19-related presenting complaint, treatment, or discharge diagnosis., Results: Among 44,816 sampled hospitalizations, 90% met the definition of likely COVID-19-attributable. Among the 9866 admissions occurring during July 2022 to September 2023, 86% were likely COVID-19-attributable; 87% had a COVID-19-related presenting complaint, 64% received steroids or COVID-19-related treatment, 47% had respiratory- and 10% had coagulopathy-related discharge diagnoses, and 39% had COVID-19 as the principal discharge diagnosis code. More than 70% met ≥ 2 criteria. Compared with likely COVID-19-attributable hospitalizations, SARS-CoV-2-positive patients who did not meet the case definition were more likely to be ages 18-49 years (27% vs. 13%), have no underlying medical conditions (14% vs. 4%), or be asymptomatic for COVID-19 upon admission (46% vs. 10%) (all p < 0.05)., Conclusions: Most hospitalizations among SARS-CoV-2-positive adults in a recent period were likely attributable to COVID-19. COVID-19-attributable hospitalizations are less common among younger SARS-CoV-2-positive hospitalized adults but still account for nearly three quarters of all admissions among SARS-CoV-2-positive adults in this age group., (Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd.)

We recently expanded the viral genomic surveillance program in Minnesota, USA, to include human respiratory syncytial virus. We performed whole-genome sequencing of 575 specimens collected at Minnesota healthcare facilities during July 2023-February 2024. Subgroups A and B differed in their genomic landscapes, and we identified 23 clusters of genetically identical genomes.

Among adults, COVID-19 hospitalization rates increase with age. Data from the COVID-19-Associated Hospitalization Surveillance Network were analyzed to estimate population-based COVID-19-associated hospitalization rates during October 2023-April 2024 and identify demographic and clinical characteristics of adults aged ≥18 years hospitalized with COVID-19. Adults aged ≥65 years accounted for 70% of all adult COVID-19-associated hospitalizations, and their COVID-19-associated hospitalization rates were higher than those among younger adult age groups. Cumulative rates of COVID-19-associated hospitalization during October 2023-April 2024 were the lowest for all adult age groups during an October-April surveillance period since 2020-2021. However, hospitalization rates among all adults aged ≥75 years approached one COVID-19-associated hospitalization for every 100 persons. Among adults hospitalized with COVID-19, 88.1% had not received the 2023-2024 formula COVID-19 vaccine before hospitalization, 80.0% had multiple underlying medical conditions, and 16.6% were residents of long-term care facilities (LTCFs). Guidance for adults at high risk for severe COVID-19 illness, including adults aged ≥65 years and residents of LTCFs, should continue to focus on adopting measures to reduce risk for contracting COVID-19, advocating for receipt of recommended COVID-19 vaccinations, and seeking prompt outpatient antiviral treatment after receipt of a positive SARS-CoV-2 test result., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Emma Mendez reports grants from the Council of State and Territorial Epidemiologists during the course of the study. No other potential conflicts of interest were disclosed.

Accurate and timely mortality surveillance is crucial for elucidating risk factors, particularly for emerging diseases. We compared use of COVID-19 keywords on death certificates alone to identify COVID-19 deaths in Minnesota, USA, during 2020-2022, with use of a standardized mortality definition incorporating additional clinical data. For analyses, we used likelihood ratio χ 2 and median 1-way tests. Death certificates alone identified 96% of COVID-19 deaths confirmed by the standardized definition and an additional 3% of deaths that had been classified as non-COVID-19 deaths by the standardized definition. Agreement between methods was >90% for most groups except children, although agreement among adults varied by demographics and location at death. Overall median time from death to filing of death certificate was 3 days; decedent characteristics and whether autopsy was performed varied. Death certificates are an efficient and timely source of COVID-19 mortality data when paired with SARS-CoV-2 testing data.

Severe outcomes were common among adults hospitalized for COVID-19 or influenza, while the percentage of COVID-19 hospitalizations involving critical care decreased from October 2021 to September 2022. During the Omicron BA.5 period, intensive care unit admission frequency was similar for COVID-19 and influenza, although patients with COVID-19 had a higher frequency of in-hospital death., Competing Interests: Potential conflicts of interest. All authors: No reported conflicts., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)

Background: Nontypeable Haemophilus influenzae (NTHi) is the most common cause of invasive H. influenzae disease in the United States (US). We evaluated the epidemiology of invasive NTHi disease in the US, including among pregnant women, infants, and people with human immunodeficiency virus (PWH)., Methods: We used data from population- and laboratory-based surveillance for invasive H. influenzae disease conducted in 10 sites to estimate national incidence of NTHi, and to describe epidemiology in women of childbearing age, infants aged ≤30 days (neonates), and PWH living in the surveillance catchment areas. H. influenzae isolates were sent to the Centers for Disease Control and Prevention for species confirmation, serotyping, and whole genome sequencing of select isolates., Results: During 2008-⁠2019, average annual NTHi incidence in the US was 1.3/100 000 population overall, 5.8/100 000 among children aged <1 year, and 10.2/100 000 among adults aged ≥80 years. Among 225 reported neonates with NTHi, 92% had a positive culture within the first week of life and 72% were preterm. NTHi risk was 23 times higher among preterm compared to term neonates, and 5.6 times higher in pregnant/postpartum compared to nonpregnant women. More than half of pregnant women with invasive NTHi had loss of pregnancy postinfection. Incidence among PWH aged ≥13 years was 9.5 cases per 100 000, compared to 1.1 cases per 100 000 for non-PWH (rate ratio, 8.3 [95% confidence interval, 7.1-9.7]; P < .0001)., Conclusions: NTHi causes substantial invasive disease, especially among older adults, pregnant/postpartum women, and neonates. Enhanced surveillance and evaluation of targeted interventions to prevent perinatal NTHi infections may be warranted., Competing Interests: Potential conflicts of interest. L. H. H. has served as a member of data and safety monitoring boards for Merck and reports reimbursement for travel expenses from Merck and Pfizer. S. P. reports funding awarded by the Connecticut Department of Public Health by the CDC (Emerging Infections Cooperative Agreement). All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2023.)

Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Ruth Lynfield reports participation on the Council of State and Territorial Epidemiologists (CSTE) Executive Board, the National Foundation of Infectious Diseases (NFID) Executive Board, the Program Committee for ID Week, and serving as associate editor of the American Academy of Pediatrics Red Book (the fee for which was donated to the Minnesota Department of Health), and receipt of support from these groups to attend CSTE, American Academy of Pediatrics Committee on Infectious Diseases, NFID, and ID Week meetings. Samuel R. Dominguez reports institutional support from Pfizer and Biofire Diagnostics, unrelated to the current work, and consulting fees (paid to his institution) from Biofire Diagnostics and Karius. Jennifer Zipprich reports that her spouse is employed by Pfizer. No other potential conflicts of interest were disclosed.

Background: Bacterial and viral infections can occur with SARS-CoV-2 infection, but prevalence, risk factors, and associated clinical outcomes are not fully understood., Methods: We used the Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET), a population-based surveillance system, to investigate the occurrence of bacterial and viral infections among hospitalized adults with laboratory-confirmed SARS-CoV-2 infection between March 2020 and April 2022. Clinician-driven testing for bacterial pathogens from sputum, deep respiratory, and sterile sites were included. The demographic and clinical features of those with and without bacterial infections were compared. We also describe the prevalence of viral pathogens including respiratory syncytial virus, rhinovirus/enterovirus, influenza, adenovirus, human metapneumovirus, parainfluenza viruses, and non-SARS-CoV-2 endemic coronaviruses., Results: Among 36 490 hospitalized adults with COVID-19, 53.3% had bacterial cultures taken within 7 days of admission and 6.0% of these had a clinically relevant bacterial pathogen. After adjustment for demographic factors and co-morbidities, bacterial infections in patients with COVID-19 within 7 days of admission were associated with an adjusted relative risk of death 2.3 times that of patients with negative bacterial testing. Staphylococcus aureus and Gram-negative rods were the most frequently isolated bacterial pathogens. Among hospitalized adults with COVID-19, 2766 (7.6%) were tested for seven virus groups. A non-SARS-CoV-2 virus was identified in 0.9% of tested patients., Conclusions: Among patients with clinician-driven testing, 6.0% of adults hospitalized with COVID-19 were identified to have bacterial coinfections and 0.9% were identified to have viral coinfections; identification of a bacterial coinfection within 7 days of admission was associated with increased mortality., Competing Interests: Ms. Leegwater and Ms. Reeg report grants from Michigan Department of Health and Human Services during the conduct of the study. Dr. Anderson reports grants from Pfizer, Merck, PaxVax, Micron, Sanofi‐Pasteur, Janssen, MedImmune, and GSK. Dr. Anderson reports personal fees from Sanofi‐Pasteur, Pfizer, Medscape, Kentucky Bioprocessing, Inc, Sanofi‐Pasteur, Janssen, GSK, WCG and ACI Clinical, and Moderna outside the submitted work. His institution has also received funding from NIH to conduct clinical trials of Moderna and Janssen COVID‐19 vaccines. Mr. Weigel reports grants from CDC/CSTE Cooperative Agreement, during the conduct of the study and grants from CDC/CSTE outside the submitted work. Mr. Teno reports grants from CDC/CSTE Cooperative Agreement during the conduct of the study and grants from CDC/CSTE outside the submitted work. Mrs. Billing reports grants from Council of State and Territorial Epidemiologists (CSTE) during the conduct of the study and grants from Centers for Disease Control and Prevention (CDC) outside the submitted work. Mr. Meek reports grants from CDC during the conduct of the study. Dr. Schaffner reports grants from CDC during the conduct of the study. Dr. Sutton reports grants from CDC Emerging Infections Program during the conduct of the study. Dr. Talbot reports grants from Centers for Disease Control and Prevention, during the conduct of the study. Ms. Yousey‐Hindes reports grants from CDC during the conduct of the study., (© 2023 The Authors. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)

Background: Pregnant women less frequently receive COVID-19 vaccination and are at increased risk for adverse pregnancy outcomes from COVID-19., Objective: This study aimed to first, describe the vaccination status, treatment, and outcomes of hospitalized, symptomatic pregnant women with COVID-19, and second, estimate whether treatment differs by pregnancy status among treatment-eligible (ie, requiring supplemental oxygen per National Institutes of Health guidelines at the time of the study) women., Study Design: From January to November 2021, the COVID-19-Associated Hospitalization Surveillance Network completed medical chart abstraction for a probability sample of 2715 hospitalized women aged 15 to 49 years with laboratory-confirmed SARS-CoV-2 infection. Of these, 1950 women had symptoms of COVID-19 on admission, and 336 were pregnant. We calculated weighted prevalence estimates of demographic and clinical characteristics, vaccination status, and outcomes among pregnant women with symptoms of COVID-19 on admission. We used propensity score matching to estimate prevalence ratios and 95% confidence intervals of treatment-eligible patients who received remdesivir or systemic steroids by pregnancy status., Results: Among 336 hospitalized pregnant women with symptomatic COVID-19, 39.6% were non-Hispanic Black, 24.8% were Hispanic or Latino, and 61.9% were aged 25 to 34 years. Among those with known COVID-19 vaccination status, 92.9% were unvaccinated. One-third (32.7%) were treatment-eligible. Among treatment-eligible pregnant women, 74.1% received systemic steroids and 61.4% received remdesivir. Among those that were no longer pregnant at discharge (n=180), 5.4% had spontaneous abortions and 3.5% had stillbirths. Of the 159 live births, 29.0% were preterm. Among a propensity score-matched cohort of treatment-eligible hospitalized women of reproductive age, pregnant women were less likely than nonpregnant women to receive remdesivir (prevalence ratio, 0.82; 95% confidence interval, 0.69-0.97) and systemic steroids (prevalence ratio, 0.80; 95% confidence interval, 0.73-0.87)., Conclusion: Most hospitalized pregnant patients with symptomatic COVID-19 were unvaccinated. Hospitalized pregnant patients were less likely to receive recommended remdesivir and systemic steroids compared with similar hospitalized nonpregnant women. Our results underscore the need to identify opportunities for improving COVID-19 vaccination, implementation of treatment of pregnant women, and the inclusion of pregnant women in clinical trials., (Published by Elsevier Inc.)

Importance: Understanding risk factors for hospitalization in vaccinated persons and the association of COVID-19 vaccines with hospitalization rates is critical for public health efforts to control COVID-19., Objective: To determine characteristics of COVID-19-associated hospitalizations among vaccinated persons and comparative hospitalization rates in unvaccinated and vaccinated persons., Design, Setting, and Participants: From January 1, 2021, to April 30, 2022, patients 18 years or older with laboratory-confirmed SARS-CoV-2 infection were identified from more than 250 hospitals in the population-based COVID-19-Associated Hospitalization Surveillance Network. State immunization information system data were linked to cases, and the vaccination coverage data of the defined catchment population were used to compare hospitalization rates in unvaccinated and vaccinated individuals. Vaccinated and unvaccinated patient characteristics were compared in a representative sample with detailed medical record review; unweighted case counts and weighted percentages were calculated., Exposures: Laboratory-confirmed COVID-19-associated hospitalization, defined as a positive SARS-CoV-2 test result within 14 days before or during hospitalization., Main Outcomes and Measures: COVID-19-associated hospitalization rates among vaccinated vs unvaccinated persons and factors associated with COVID-19-associated hospitalization in vaccinated persons were assessed., Results: Using representative data from 192 509 hospitalizations (see Table 1 for demographic information), monthly COVID-19-associated hospitalization rates ranged from 3.5 times to 17.7 times higher in unvaccinated persons than vaccinated persons regardless of booster dose status. From January to April 2022, when the Omicron variant was predominant, hospitalization rates were 10.5 times higher in unvaccinated persons and 2.5 times higher in vaccinated persons with no booster dose, respectively, compared with those who had received a booster dose. Among sampled cases, vaccinated hospitalized patients with COVID-19 were older than those who were unvaccinated (median [IQR] age, 70 [58-80] years vs 58 [46-70] years, respectively; P < .001) and more likely to have 3 or more underlying medical conditions (1926 [77.8%] vs 4124 [51.6%], respectively; P < .001)., Conclusions and Relevance: In this cross-sectional study of US adults hospitalized with COVID-19, unvaccinated adults were more likely to be hospitalized compared with vaccinated adults; hospitalization rates were lowest in those who had received a booster dose. Hospitalized vaccinated persons were older and more likely to have 3 or more underlying medical conditions and be long-term care facility residents compared with hospitalized unvaccinated persons. The study results suggest that clinicians and public health practitioners should continue to promote vaccination with all recommended doses for eligible persons.

Objectives: This study assessed the associations between parent intent to have their child receive the COVID-19 vaccination, and demographic factors and various child activities, including attendance at in-person education or childcare. Methods: Persons undergoing COVID-19 testing residing in Minnesota and Los Angeles County, California with children aged <12 years completed anonymous internet-based surveys between 10 May and 6 September 2021 to assess factors associated with intention to vaccinate their child. Factors influencing the parents’ decision to have their child attend in-person school or childcare were examined. Estimated adjusted odds rations (AORs, 95% CI) were computed between parents’ intentions regarding children’s COVID-19 vaccination and participation in school and extra-curricular activities using multinomial logistic regression. Results: Compared to parents intending to vaccinate their children (n = 4686 [77.2%]), those undecided (n = 874 [14.4%]) or without intention to vaccinate (n = 508 [8.4%]) tended to be younger, non-White, less educated, and themselves not vaccinated against COVID-19. Their children more commonly participated in sports (aOR:1.51 1.17−1.95) and in-person faith or community activities (aOR:4.71 3.62−6.11). A greater proportion of parents without intention to vaccinate (52.5%) indicated that they required no more information to make their decision in comparison to undecided parents (13.2%). They further indicated that additional information regarding vaccine safety and effectiveness would influence their decision. COVID-19 mitigation measures were the most common factors influencing parents’ decision to have their child attend in-person class or childcare. Conclusions: Several demographic and socioeconomic factors are associated with parents’ decision whether to vaccinate their <12-year-old children for COVID-19. Child participation in in-person activities was associated with parents’ intentions not to vaccinate. Tailored communications may be useful to inform parents’ decisions regarding the safety and effectiveness of vaccination.

Responding to measles outbreaks in the United States puts a considerable strain on public health resources, and limited research exists about the effectiveness of containment strategies. In this paper we quantify the impact of isolation, contact tracing, and exclusion in reducing transmission during a measles outbreak in an under-vaccinated community., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Objectives: Routine surveillance for streptococcal toxic shock syndrome (STSS), a severe manifestation of invasive group A Streptococcus (GAS) infections, likely underestimates its true incidence. The objective of our study was to evaluate routine identification of STSS in a national surveillance system for invasive GAS infections., Methods: Active Bacterial Core surveillance (ABCs) conducts active population-based surveillance for invasive GAS disease in selected US counties in 10 states. We categorized invasive GAS cases with a diagnosis of STSS made by a physician as STSS-physician and cases that met the Council of State and Territorial Epidemiologists (CSTE) clinical criteria for STSS based on data in the medical record as STSS-CSTE. We evaluated agreement between the 2 methods for identifying STSS and compared the estimated national incidence of STSS when applying proportions of STSS-CSTE and STSS-physician among invasive GAS cases from this study with national invasive GAS estimates for 2017., Results: During 2014-2017, of 7572 invasive GAS cases in ABCs, we identified 1094 (14.4%) as STSS-CSTE and 203 (2.7%) as STSS-physician, a 5.3-fold difference. Of 1094 STSS-CSTE cases, we identified only 132 (12.1%) as STSS-physician cases. Agreement between the 2 methods for identifying STSS was low (κ = 0.17; 95% CI, 0.14-0.19). Using ABCs data, we estimated 591 cases of STSS-physician and 3618 cases of STSS-CSTE occurred nationally in 2017., Conclusions: We found a large difference in estimates of incidence of STSS when applying different surveillance methods and definitions. These results should help with better use of currently available surveillance data to estimate the incidence of STSS and to evaluate disease prevention efforts, in addition to guiding future surveillance efforts for STSS.

The Minnesota Department of Health investigated a coronavirus disease 2019 (COVID-19) outbreak at a fitness center in Olmsted County, Minnesota. Twenty-three severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections (5 employees and 18 members) were identified. An epidemiological investigation supported by whole genome sequencing demonstrated that transmission of SARS-CoV-2 occurred at the fitness center despite following recommended prevention strategies., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Beginning the week of December 19-25, 2021, the B.1.1.529 (Omicron) variant of SARS-CoV-2 (the virus that causes COVID-19) became the predominant circulating variant in the United States (i.e., accounted for >50% of sequenced isolates).* Information on the impact that booster or additional doses of COVID-19 vaccines have on preventing hospitalizations during Omicron predominance is limited. Data from the COVID-19-Associated Hospitalization Surveillance Network (COVID-NET) † were analyzed to compare COVID-19-associated hospitalization rates among adults aged ≥18 years during B.1.617.2 (Delta; July 1-December 18, 2021) and Omicron (December 19, 2021-January 31, 2022) variant predominance, overall and by race/ethnicity and vaccination status. During the Omicron-predominant period, weekly COVID-19-associated hospitalization rates (hospitalizations per 100,000 adults) peaked at 38.4, compared with 15.5 during Delta predominance. Hospitalizations rates increased among all adults irrespective of vaccination status (unvaccinated, primary series only, or primary series plus a booster or additional dose). Hospitalization rates during peak Omicron circulation (January 2022) among unvaccinated adults remained 12 times the rates among vaccinated adults who received booster or additional doses and four times the rates among adults who received a primary series, but no booster or additional dose. The rate among adults who received a primary series, but no booster or additional dose, was three times the rate among adults who received a booster or additional dose. During the Omicron-predominant period, peak hospitalization rates among non-Hispanic Black (Black) adults were nearly four times the rate of non-Hispanic White (White) adults and was the highest rate observed among any racial and ethnic group during the pandemic. Compared with the Delta-predominant period, the proportion of unvaccinated hospitalized Black adults increased during the Omicron-predominant period. All adults should stay up to date (1) with COVID-19 vaccination to reduce their risk for COVID-19-associated hospitalization. Implementing strategies that result in the equitable receipt of COVID-19 vaccinations, through building vaccine confidence, raising awareness of the benefits of vaccination, and removing barriers to vaccination access among persons with disproportionately higher hospitalizations rates from COVID-19, including Black adults, is an urgent public health priority., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Evan J. Anderson reports grants from Pfizer, Merck, PaxVax, Micron, Sanofi-Pasteur, Janssen, MedImmune, and GlaxoSmithKline; personal fees from Pfizer, Medscape, Kentucky Bioprocessing, Inc., Sanofi-Pasteur, and Janssen, outside the submitted work; and institutional funding from the National Institutes of Health to conduct clinical trials of Moderna and Janssen COVID-19 vaccines. Laurie M. Billing and Kenzie Teno report grants from the Council of State and Territorial Epidemiologists during the conduct of the study. Libby Reeg reports grants from the Michigan Department of Health and Human Services during the conduct of the study. No other potential conflicts of interest were disclosed.

Background: Respiratory syncytial virus (RSV) can cause severe disease in adults with cardiopulmonary conditions, such as congestive heart failure (CHF). We quantified the rate of RSV-associated hospitalization in adults by CHF status using population-based surveillance in the United States., Methods: Population-based surveillance for RSV (RSV-NET) was performed in 35 counties in seven sites during two respiratory seasons (2015-2017) from October 1-April 30. Adults (≥18 years) admitted to a hospital within the surveillance catchment area with laboratory-confirmed RSV identified by clinician-directed testing were included. Presence of underlying CHF was determined by medical chart abstraction. We calculated overall and age-stratified (<65 years and ≥65 years) RSV-associated hospitalization rates by CHF status. Estimates were adjusted for age and the under-detection of RSV. We also report rate differences (RD) and rate ratios (RR) by comparing the rates for those with and without CHF., Results: 2042 hospitalized RSV cases with CHF status recorded were identified. Most (60.2%, n = 1230) were ≥65 years, and 28.3% (n = 577) had CHF. The adjusted RSV hospitalization rate was 26.7 (95% CI: 22.2, 31.8) per 10,000 population in adults with CHF versus 3.3 (95% CI: 3.3, 3.3) per 10,000 in adults without CHF (RR: 8.1, 95% CI: 6.8, 9.7; RD: 23.4, 95% CI: 18.9, 28.5). Adults with CHF had higher rates of RSV-associated hospitalization in both age groups (<65 years and ≥65 years). Adults ≥65 years with CHF had the highest rate (40.5 per 10,000 population, 95% CI: 35.1, 46.6)., Conclusions: Adults with CHF had 8 times the rate of RSV-associated hospitalization compared with adults without CHF. Identifying high-risk populations for RSV infection can inform future RSV vaccination policies and recommendations., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: Evan Anderson reports personal fees from AbbVie, Pfizer and Sanofi Pasteur, and grants from MedImmune, Regeneron, PaxVax, Pfizer, GSK, Merck, Novavax, Sanofi Pasteur, Micron, and Janssen, outside the submitted work. He also serves on the data safety monitoring committee for Kentucky Bioscience. Stephanie Kujawski is currently an employee of Merck Sharp & Dohme Corp, a subsidiary of Merck & Co., Inc, Kenilworth, NJ, USA, and may own stock or hold stock options in the Company.

The first U.S. case of COVID-19 attributed to the Omicron variant of SARS-CoV-2 (the virus that causes COVID-19) was reported on December 1, 2021 (1), and by the week ending December 25, 2021, Omicron was the predominant circulating variant in the United States.* Although COVID-19-associated hospitalizations are more frequent among adults, † COVID-19 can lead to severe outcomes in children and adolescents (2). This report analyzes data from the Coronavirus Disease 19-Associated Hospitalization Surveillance Network (COVID-NET) § to describe COVID-19-associated hospitalizations among U.S. children (aged 0-11 years) and adolescents (aged 12-17 years) during periods of Delta (July 1-December 18, 2021) and Omicron (December 19, 2021-January 22, 2022) predominance. During the Delta- and Omicron-predominant periods, rates of weekly COVID-19-associated hospitalizations per 100,000 children and adolescents peaked during the weeks ending September 11, 2021, and January 8, 2022, respectively. The Omicron variant peak (7.1 per 100,000) was four times that of the Delta variant peak (1.8), with the largest increase observed among children aged 0-4 years. ¶ During December 2021, the monthly hospitalization rate among unvaccinated adolescents aged 12-17 years (23.5) was six times that among fully vaccinated adolescents (3.8). Strategies to prevent COVID-19 among children and adolescents, including vaccination of eligible persons, are critical.*., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Evan J. Anderson reports grants from Pfizer, Merck, PaxVax, Micron, Sanofi-Pasteur, Janssen, MedImmune, and GlaxoSmithKline; personal fees from Pfizer, Medscape, Kentucky Bioprocessing, Inc., Sanofi-Pasteur, and Janssen, outside the submitted work; and institutional funding from the National Institutes of Health to conduct clinical trials of Moderna and Janssen COVID-19 vaccines. Laurie M. Billing, Eli Shiltz, Andy Weigel, Justin Henderson, Val Tellez Nunez, and Andrea George report grants from the Council of State and Territorial Epidemiologists during the conduct of the study. Ruth Lynfield reports editorial payments from the American Academy of Pediatrics Red Book (Committee on Infectious Diseases), which were donated to the Minnesota Department of Health. No other potential conflicts of interest were disclosed.

During November 19-21, 2021, an indoor convention (event) in New York City (NYC), was attended by approximately 53,000 persons from 52 U.S. jurisdictions and 30 foreign countries. In-person registration for the event began on November 18, 2021. The venue was equipped with high efficiency particulate air (HEPA) filtration, and attendees were required to wear a mask indoors and have documented receipt of at least 1 dose of a COVID-19 vaccine.* On December 2, 2021, the Minnesota Department of Health reported the first case of community-acquired COVID-19 in the United States caused by the SARS-CoV-2 B.1.1.529 (Omicron) variant in a person who had attended the event (1). CDC collaborated with state and local health departments to assess event-associated COVID-19 cases and potential exposures among U.S.-based attendees using data from COVID-19 surveillance systems and an anonymous online attendee survey. Among 34,541 attendees with available contact information, surveillance data identified test results for 4,560, including 119 (2.6%) persons from 16 jurisdictions with positive SARS-CoV-2 test results. Most (4,041 [95.2%]), survey respondents reported always wearing a mask while indoors at the event. Compared with test-negative respondents, test-positive respondents were more likely to report attending bars, karaoke, or nightclubs, and eating or drinking indoors near others for at least 15 minutes. Among 4,560 attendees who received testing, evidence of widespread transmission during the event was not identified. Genomic sequencing of 20 specimens identified the SARS-CoV-2 B.1.617.2 (Delta) variant (AY.25 and AY.103 sublineages) in 15 (75%) cases, and the Omicron variant (BA.1 sublineage) in five (25%) cases. These findings reinforce the importance of implementing multiple, simultaneous prevention measures, such as ensuring up-to-date vaccination, mask use, physical distancing, and improved ventilation in limiting SARS-CoV-2 transmission, during large, indoor events. † ., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Ruth Lynfield reports unpaid positions as the President of the Council of State and Territorial Epidemiologists and on the National Foundation for Infectious Diseases Executive Board. Ruby Serrano reports honoraria from Ponce Health Sciences University. No other potential conflicts of interest were disclosed.

Background: Reported outbreaks of invasive group A Streptococcus (iGAS) infections among people who inject drugs (PWID) and people experiencing homelessness (PEH) have increased, concurrent with rising US iGAS rates. We describe epidemiology among iGAS patients with these risk factors., Methods: We analyzed iGAS infections from population-based Active Bacterial Core surveillance (ABCs) at 10 US sites from 2010 to 2017. Cases were defined as GAS isolated from a normally sterile site or from a wound in patients with necrotizing fasciitis or streptococcal toxic shock syndrome. GAS isolates were emm typed. We categorized iGAS patients into four categories: injection drug use (IDU) only, homelessness only, both, and neither. We calculated annual change in prevalence of these risk factors using log binomial regression models. We estimated national iGAS infection rates among PWID and PEH., Results: We identified 12 386 iGAS cases; IDU, homelessness, or both were documented in ~13%. Skin infections and acute skin breakdown were common among iGAS patients with documented IDU or homelessness. Endocarditis was 10-fold more frequent among iGAS patients with documented IDU only versus those with neither risk factor. Average percentage yearly increase in prevalence of IDU and homelessness among iGAS patients was 17.5% and 20.0%, respectively. iGAS infection rates among people with documented IDU or homelessness were ~14-fold and 17- to 80-fold higher, respectively, than among people without those risks., Conclusions: IDU and homelessness likely contribute to increases in US incidence of iGAS infections. Improving management of skin breakdown and early recognition of skin infection could prevent iGAS infections in these patients., (Published by Oxford University Press for the Infectious Diseases Society of America 2020.)

Background: The COVID-19 pandemic has caused substantial morbidity and mortality., Objective: To describe monthly clinical trends among adults hospitalized with COVID-19., Design: Pooled cross-sectional study., Setting: 99 counties in 14 states participating in the Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET)., Patients: U.S. adults (aged ≥18 years) hospitalized with laboratory-confirmed COVID-19 during 1 March to 31 December 2020., Measurements: Monthly hospitalizations, intensive care unit (ICU) admissions, and in-hospital death rates per 100 000 persons in the population; monthly trends in weighted percentages of interventions, including ICU admission, mechanical ventilation, and vasopressor use, among an age- and site-stratified random sample of hospitalized case patients., Results: Among 116 743 hospitalized adults with COVID-19, the median age was 62 years, 50.7% were male, and 40.8% were non-Hispanic White. Monthly rates of hospitalization (105.3 per 100 000 persons), ICU admission (20.2 per 100 000 persons), and death (11.7 per 100 000 persons) peaked during December 2020. Rates of all 3 outcomes were highest among adults aged 65 years or older, males, and Hispanic or non-Hispanic Black persons. Among 18 508 sampled hospitalized adults, use of remdesivir and systemic corticosteroids increased from 1.7% and 18.9%, respectively, in March to 53.8% and 74.2%, respectively, in December. Frequency of ICU admission, mechanical ventilation, and vasopressor use decreased from March (37.8%, 27.8%, and 22.7%, respectively) to December (20.5%, 12.3%, and 12.8%, respectively); use of noninvasive respiratory support increased from March to December., Limitation: COVID-NET covers approximately 10% of the U.S. population; findings may not be generalizable to the entire country., Conclusion: Rates of COVID-19-associated hospitalization, ICU admission, and death were highest in December 2020, corresponding with the third peak of the U.S. pandemic. The frequency of intensive interventions for management of hospitalized patients decreased over time. These data provide a longitudinal assessment of clinical trends among adults hospitalized with COVID-19 before widespread implementation of COVID-19 vaccines., Primary Funding Source: Centers for Disease Control and Prevention.

Although COVID-19-associated hospitalizations and deaths have occurred more frequently in adults, † COVID-19 can also lead to severe outcomes in children and adolescents (1,2). Schools are opening for in-person learning, and many prekindergarten children are returning to early care and education programs during a time when the number of COVID-19 cases caused by the highly transmissible B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19, is increasing. § Therefore, it is important to monitor indicators of severe COVID-19 among children and adolescents. This analysis uses Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET) ¶ data to describe COVID-19-associated hospitalizations among U.S. children and adolescents aged 0-17 years. During March 1, 2020-August 14, 2021, the cumulative incidence of COVID-19-associated hospitalizations was 49.7 per 100,000 children and adolescents. The weekly COVID-19-associated hospitalization rate per 100,000 children and adolescents during the week ending August 14, 2021 (1.4) was nearly five times the rate during the week ending June 26, 2021 (0.3); among children aged 0-4 years, the weekly hospitalization rate during the week ending August 14, 2021, was nearly 10 times that during the week ending June 26, 2021.** During June 20-July 31, 2021, the hospitalization rate among unvaccinated adolescents (aged 12-17 years) was 10.1 times higher than that among fully vaccinated adolescents. Among all hospitalized children and adolescents with COVID-19, the proportions with indicators of severe disease (such as intensive care unit [ICU] admission) after the Delta variant became predominant (June 20-July 31, 2021) were similar to those earlier in the pandemic (March 1, 2020-June 19, 2021). Implementation of preventive measures to reduce transmission and severe outcomes in children is critical, including vaccination of eligible persons, universal mask wearing in schools, recommended mask wearing by persons aged ≥2 years in other indoor public spaces and child care centers, †† and quarantining as recommended after exposure to persons with COVID-19. §§ ., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. William Schaffner reports consultant fees from VBI Vaccines, outside the submitted work. Eli Shiltz and Laurie M. Billing report grant funding from the Council of State and Territorial Epidemiologists (CSTE) for the population-based Influenza Hospitalization Surveillance Project (IHSP) and COVID-NET activities. Lauren Leegwater and Sue Kim report grant support from CSTE through the Michigan Department of Health and Human Services. Andy Weigel and Kenzie Teno report grant support from CSTE for data collection and participation in ongoing meetings related to COVID-19 hospitalization surveillance. Evan J. Anderson reports grants for clinical trials from Pfizer, Merck, PaxVax, Micron, Sanofi-Pasteur, Janssen, MedImmune, and GSK; consulting fees from Sanofi-Pasteur, Pfizer, Janssen, and Medscape; personal fees for data safety monitoring board participation from Kentucky Bioprocessing, Inc. and Sanofi-Pasteur; and institutional funding from the National Institutes of Health to conduct clinical trials of Moderna and Janssen COVID-19 vaccines. No other potential conflicts of interest were disclosed.

Clinical trials of COVID-19 vaccines currently authorized for emergency use in the United States (Pfizer-BioNTech, Moderna, and Janssen [Johnson & Johnson]) indicate that these vaccines have high efficacy against symptomatic disease, including moderate to severe illness (1-3). In addition to clinical trials, real-world assessments of COVID-19 vaccine effectiveness are critical in guiding vaccine policy and building vaccine confidence, particularly among populations at higher risk for more severe illness from COVID-19, including older adults. To determine the real-world effectiveness of the three currently authorized COVID-19 vaccines among persons aged ≥65 years during February 1-April 30, 2021, data on 7,280 patients from the COVID-19-Associated Hospitalization Surveillance Network (COVID-NET) were analyzed with vaccination coverage data from state immunization information systems (IISs) for the COVID-NET catchment area (approximately 4.8 million persons). Among adults aged 65-74 years, effectiveness of full vaccination in preventing COVID-19-associated hospitalization was 96% (95% confidence interval [CI] = 94%-98%) for Pfizer-BioNTech, 96% (95% CI = 95%-98%) for Moderna, and 84% (95% CI = 64%-93%) for Janssen vaccine products. Effectiveness of full vaccination in preventing COVID-19-associated hospitalization among adults aged ≥75 years was 91% (95% CI = 87%-94%) for Pfizer-BioNTech, 96% (95% CI = 93%-98%) for Moderna, and 85% (95% CI = 72%-92%) for Janssen vaccine products. COVID-19 vaccines currently authorized in the United States are highly effective in preventing COVID-19-associated hospitalizations in older adults. In light of real-world data demonstrating high effectiveness of COVID-19 vaccines among older adults, efforts to increase vaccination coverage in this age group are critical to reducing the risk for COVID-19-related hospitalization., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Evan J. Anderson reports grants from Pfizer, Merck, PaxVax, Micron, Sanofi-Pasteur, Janssen, MedImmune, and GSK; personal fees from Sanofi-Pasteur, Pfizer, Medscape, Kentucky Bioprocessing, Inc, Janssen, outside the submitted work; and his institution has also received funding from NIH to conduct clinical trials of Moderna and Janssen COVID-19 vaccines. Sue Kim reports grants from Michigan Department of Health and Human Services, during the conduct of the study. William Schaffner reports personal fees from VBI Vaccines, outside the submitted work. Jessica Shiltz reports grants from Council for State and Territorial Epidemiologists during the conduct of the study. No other potential conflicts of interest were disclosed.

Coronavirus disease has disproportionately affected persons in congregate settings and high-density workplaces. To determine more about the transmission patterns of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in these settings, we performed whole-genome sequencing and phylogenetic analysis on 319 (14.4%) samples from 2,222 SARS-CoV-2-positive persons associated with 8 outbreaks in Minnesota, USA, during March-June 2020. Sequencing indicated that virus spread in 3 long-term care facilities and 2 correctional facilities was associated with a single genetic sequence and that in a fourth long-term care facility, outbreak cases were associated with 2 distinct sequences. In contrast, cases associated with outbreaks in 2 meat-processing plants were associated with multiple SARS-CoV-2 sequences. These results suggest that a single introduction of SARS-CoV-2 into a facility can result in a widespread outbreak. Early identification and cohorting (segregating) of virus-positive persons in these settings, along with continued vigilance with infection prevention and control measures, is imperative.

Most COVID-19-associated hospitalizations occur in older adults, but severe disease that requires hospitalization occurs in all age groups, including adolescents aged 12-17 years (1). On May 10, 2021, the Food and Drug Administration expanded the Emergency Use Authorization for Pfizer-BioNTech COVID-19 vaccine to include persons aged 12-15 years, and CDC's Advisory Committee on Immunization Practices recommended it for this age group on May 12, 2021.* Before that time, COVID-19 vaccines had been available only to persons aged ≥16 years. Understanding and describing the epidemiology of COVID-19-associated hospitalizations in adolescents and comparing it with adolescent hospitalizations associated with other vaccine-preventable respiratory viruses, such as influenza, offers evidence of the benefits of expanding the recommended age range for vaccination and provides a baseline and context from which to assess vaccination impact. Using the Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET), CDC examined COVID-19-associated hospitalizations among adolescents aged 12-17 years, including demographic and clinical characteristics of adolescents admitted during January 1-March 31, 2021, and hospitalization rates (hospitalizations per 100,000 persons) among adolescents during March 1, 2020-April 24, 2021. Among 204 adolescents who were likely hospitalized primarily for COVID-19 during January 1-March 31, 2021, 31.4% were admitted to an intensive care unit (ICU), and 4.9% required invasive mechanical ventilation; there were no associated deaths. During March 1, 2020-April 24, 2021, weekly adolescent hospitalization rates peaked at 2.1 per 100,000 in early January 2021, declined to 0.6 in mid-March, and then rose to 1.3 in April. Cumulative COVID-19-associated hospitalization rates during October 1, 2020-April 24, 2021, were 2.5-3.0 times higher than were influenza-associated hospitalization rates from three recent influenza seasons (2017-18, 2018-19, and 2019-20) obtained from the Influenza Hospitalization Surveillance Network (FluSurv-NET). Recent increased COVID-19-associated hospitalization rates in March and April 2021 and the potential for severe disease in adolescents reinforce the importance of continued COVID-19 prevention measures, including vaccination and correct and consistent wearing of masks by persons not yet fully vaccinated or when required by laws, rules, or regulations. † ., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Andrea George, Laurie M. Billing, Libby Reeg, Alexander Kohrman, Andrew Weigel, Kenzie Teno, and Jess Shiltz report grant funding from the Council of State and Territorial Epidemiologists. William Schaffner reports personal fees from VBI Vaccines. Evan J. Anderson reports grants for clinical trials from Pfizer, Merck, PaxVax, Micron, Sanofi-Pasteur, Janssen, MedImmune and GSK, and personal fees for consulting from Sanofi-Pasteur, Pfizer, and Medscape, and for data safety monitoring board service from Kentucky Bioprocessing, Inc. and Sanofi-Pasteur; and funding from the National Institutes of Health to conduct clinical trials of Moderna and Janssen COVID-19 vaccines. No other potential conflicts of interest were disclosed.

Background: Currently, the United States has the largest number of reported coronavirus disease 2019 (COVID-19) cases and deaths globally. Using a geographically diverse surveillance network, we describe risk factors for severe outcomes among adults hospitalized with COVID-19., Methods: We analyzed data from 2491 adults hospitalized with laboratory-confirmed COVID-19 between 1 March-2 May 2020, as identified through the Coronavirus Disease 2019-Associated Hospitalization Surveillance Network, which comprises 154 acute-care hospitals in 74 counties in 13 states. We used multivariable analyses to assess associations between age, sex, race and ethnicity, and underlying conditions with intensive care unit (ICU) admission and in-hospital mortality., Results: The data show that 92% of patients had ≥1 underlying condition; 32% required ICU admission; 19% required invasive mechanical ventilation; and 17% died. Independent factors associated with ICU admission included ages 50-64, 65-74, 75-84, and ≥85 years versus 18-39 years (adjusted risk ratios [aRRs], 1.53, 1.65, 1.84, and 1.43, respectively); male sex (aRR, 1.34); obesity (aRR, 1.31); immunosuppression (aRR, 1.29); and diabetes (aRR, 1.13). Independent factors associated with in-hospital mortality included ages 50-64, 65-74, 75-84, and ≥ 85 years versus 18-39 years (aRRs, 3.11, 5.77, 7.67, and 10.98, respectively); male sex (aRR, 1.30); immunosuppression (aRR, 1.39); renal disease (aRR, 1.33); chronic lung disease (aRR 1.31); cardiovascular disease (aRR, 1.28); neurologic disorders (aRR, 1.25); and diabetes (aRR, 1.19)., Conclusions: In-hospital mortality increased markedly with increasing age. Aggressive implementation of prevention strategies, including social distancing and rigorous hand hygiene, may benefit the population as a whole, as well as those at highest risk for COVID-19-related complications., (Published by Oxford University Press for the Infectious Diseases Society of America 2020.)

Background: Respiratory syncytial virus (RSV) infection causes substantial morbidity and mortality in children and adults. Socioeconomic status (SES) is known to influence many health outcomes, but there have been few studies of the relationship between RSV-associated illness and SES, particularly in adults. Understanding this association is important in order to identify and address disparities and to prioritize resources for prevention., Methods: Adults hospitalized with a laboratory-confirmed RSV infection were identified through population-based surveillance at multiple sites in the U.S. The incidence of RSV-associated hospitalizations was calculated by census-tract (CT) poverty and crowding, adjusted for age. Log binomial regression was used to evaluate the association between Intensive Care Unit (ICU) admission or death and CT poverty and crowding., Results: Among the 1713 cases, RSV-associated hospitalization correlated with increased CT level poverty and crowding. The incidence rate of RSV-associated hospitalization was 2.58 (CI 2.23, 2.98) times higher in CTs with the highest as compared to the lowest percentages of individuals living below the poverty level (≥ 20 and < 5%, respectively). The incidence rate of RSV-associated hospitalization was 1.52 (CI 1.33, 1.73) times higher in CTs with the highest as compared to the lowest levels of crowding (≥5 and < 1% of households with > 1 occupant/room, respectively). Neither CT level poverty nor crowding had a correlation with ICU admission or death., Conclusions: Poverty and crowding at CT level were associated with increased incidence of RSV-associated hospitalization, but not with more severe RSV disease. Efforts to reduce the incidence of RSV disease should consider SES.

Since December 2020, the Minnesota Department of Health (MDH) Public Health Laboratory has been receiving 100 specimens per week (50 from each of two clinical partners) with low cycle threshold (Ct) values for routine surveillance for SARS-CoV-2, the virus that causes COVID-19. On January 25, 2021, MDH identified the SARS-CoV-2 variant P.1 in one specimen through this surveillance system using whole genome sequencing, representing the first identified case of this variant in the United States. The P.1 variant was first identified in travelers from Brazil during routine airport screening in Tokyo, Japan, in early January 2021 (1). This variant has been associated with increased transmissibility (2), and there are concerns that mutations in the spike protein receptor-binding domain might disrupt both vaccine-induced and natural immunity (3,4). As of February 28, 2021, a total of 10 P.1 cases had been identified in the United States, including the two cases described in this report, followed by one case each in Alaska, Florida, Maryland, and Oklahoma (5)., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

Among 513 adults aged 18-49 years without underlying medical conditions hospitalized with coronavirus disease 2019 (COVID-19) during March 2020-August 2020, 22% were admitted to an intensive care unit, 10% required mechanical ventilation, and 3 patients died (0.6%). These data demonstrate that healthy younger adults can develop severe COVID-19., (Published by Oxford University Press for the Infectious Diseases Society of America 2020.)

On January 9, 2021, the Minnesota Department of Health (MDH) announced the identification of the SARS-CoV-2 variant of concern (VOC) B.1.1.7, also referred to as 20I/501Y.V1 and VOC 202012/01, in specimens from five persons; on January 25, MDH announced the identification of this variant in specimens from three additional persons. The B.1.1.7 variant, which is reported to be more transmissible than certain other SARS-CoV-2 lineages* , † (1), was first reported in the United Kingdom in December 2020 (1). As of February 14, 2021, a total of 1,173 COVID-19 cases of the B.1.1.7 variant had been identified in 39 U.S. states and the District of Columbia (2). Modeling data suggest that B.1.1.7 could become the predominant variant in the United States in March 2021 (3)., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

During August 7-16, 2020, a motorcycle rally was held in western South Dakota that attracted approximately 460,000 persons from across the United States to numerous indoor and outdoor events over a 10-day period. During August-September 2020, the Minnesota Department of Health (MDH) investigated a coronavirus disease 2019 (COVID-19) outbreak associated with the rally in Minnesota residents. Fifty-one primary event-associated cases were identified, and 35 secondary or tertiary cases occurred among household, social, and workplace contacts, for a total of 86 cases; four patients were hospitalized, and one died. Approximately one third (34%) of 87 counties in Minnesota had at least one primary, secondary, or tertiary case associated with this rally. Genomic sequencing supported the associations with the motorcycle rally. These findings support current recommendations for mask use, physical distancing, reducing the number of attendees at gatherings, isolation for patients with COVID-19, and quarantine for close contacts to slow the spread of SARS-CoV-2 (1). Furthermore, although these findings did not capture the impact of the motorcycle rally on residents of other states, they demonstrate the rationale for consistent mitigation measures across states., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Matthew J. Binnicker reports personal fees from DiaSorin Molecular for an educational webinar on COVID-19 diagnostics and as a member of the advisory board. No other potential conflicts of interest were disclosed.

Background: Respiratory syncytial virus (RSV) is a major cause of hospitalizations in young children. We estimated the burden of community-onset RSV-associated hospitalizations among US children aged <2 years by extrapolating rates of RSV-confirmed hospitalizations in 4 surveillance states and using probabilistic multipliers to adjust for ascertainment biases., Methods: From October 2014 through April 2015, clinician-ordered RSV tests identified laboratory-confirmed RSV hospitalizations among children aged <2 years at 4 influenza hospitalization surveillance network sites. Surveillance populations were used to estimate age-specific rates of RSV-associated hospitalization, after adjusting for detection probabilities. We extrapolated these rates using US census data., Results: We identified 1554 RSV-associated hospitalizations in children aged <2 years. Of these, 27% were admitted to an intensive care unit, 6% needed mechanical ventilation, and 5 died. Most cases (1047/1554; 67%) had no underlying condition. Adjusted age-specific RSV hospitalization rates per 100 000 population were 1970 (95% confidence interval [CI],1787 to 2177), 897 (95% CI, 761 to 1073), 531 (95% CI, 459 to 624), and 358 (95% CI, 317 to 405) for ages 0-2, 3-5, 6-11, and 12-23 months, respectively. Extrapolating to the US population, an estimated 49 509-59 867 community-onset RSV-associated hospitalizations among children aged <2 years occurred during the 2014-2015 season., Conclusions: Our findings highlight the importance of RSV as a cause of hospitalization, especially among children aged <2 months. Our approach to estimating RSV-related hospitalizations could be used to provide a US baseline for assessing the impact of future interventions., (Published by Oxford University Press on behalf of The Journal of the Pediatric Infectious Diseases Society 2019.)

Using a coronavirus disease 2019 (COVID-19)-associated hospitalization surveillance network, we found that 42.5% of hospitalized COVID-19 cases with available data from March 1-June 30, 2020, received ≥1 COVID-19 investigational treatment. Hydroxychloroquine, azithromycin, and remdesivir were used frequently; however, hydroxychloroquine and azithromycin use declined over time, while use of remdesivir increased., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2020. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Health care personnel (HCP) can be exposed to SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), both within and outside the workplace, increasing their risk for infection. Among 6,760 adults hospitalized during March 1-May 31, 2020, for whom HCP status was determined by the COVID-19-Associated Hospitalization Surveillance Network (COVID-NET), 5.9% were HCP. Nursing-related occupations (36.3%) represented the largest proportion of HCP hospitalized with COVID-19. Median age of hospitalized HCP was 49 years, and 89.8% had at least one underlying medical condition, of which obesity was most commonly reported (72.5%). A substantial proportion of HCP with COVID-19 had indicators of severe disease: 27.5% were admitted to an intensive care unit (ICU), 15.8% required invasive mechanical ventilation, and 4.2% died during hospitalization. HCP can have severe COVID-19-associated illness, highlighting the need for continued infection prevention and control in health care settings as well as community mitigation efforts to reduce transmission., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Evan J. Anderson reports personal fees from AbbVie, Kentucky BioProcessing, Inc., Pfizer, and Sanofi Pasteur, grants from MedImmune, Regeneron, PaxVax, Pfizer, GSK, Merck, Novavax, Sanofi Pasteur, Micron, and Janssen, outside the submitted work; William Schaffner reports personal fees from VBI Vaccines outside the submitted work. No other potential conflicts of interest were disclosed.

Background: Respiratory syncytial virus (RSV) typically causes winter outbreaks in temperate climates. During summer 2017, the Minnesota Department of Health received a report of increased cases of severe RSV-B infection., Methods: We compared characteristics of summer 2017 cases with those of 2014-2018 summers. To understand the genetic relatedness among viruses, we performed high-throughput sequencing of RSV from patients with a spectrum of illness from sites in Minnesota and Wisconsin., Results: From May to September 2017, 58 RSV cases (43 RSV-B) were reported compared to 20-29 cases (3-7 RSV-B) during these months in other years. Median age and frequency of comorbidities were similar, but 55% (24/43) were admitted to the ICU in 2017 compared to 12% in preceding 3 years (odds ratio, 4.84, P < .01). Sequencing was performed on 137 specimens from March 2016 to March 2018. Outbreak cases formed a unique clade sharing a single conserved nonsynonymous change in the SH gene. We observed increased cases during the following winter season, when the new lineage was the predominant strain., Conclusions: We identified an outbreak of severe RSV-B disease associated with a new genetic lineage among urban Minnesota children during a time of expected low RSV circulation., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Since SARS-CoV-2, the novel coronavirus that causes coronavirus disease 2019 (COVID-19), was first detected in December 2019 (1), approximately 1.3 million cases have been reported worldwide (2), including approximately 330,000 in the United States (3). To conduct population-based surveillance for laboratory-confirmed COVID-19-associated hospitalizations in the United States, the COVID-19-Associated Hospitalization Surveillance Network (COVID-NET) was created using the existing infrastructure of the Influenza Hospitalization Surveillance Network (FluSurv-NET) (4) and the Respiratory Syncytial Virus Hospitalization Surveillance Network (RSV-NET). This report presents age-stratified COVID-19-associated hospitalization rates for patients admitted during March 1-28, 2020, and clinical data on patients admitted during March 1-30, 2020, the first month of U.S. surveillance. Among 1,482 patients hospitalized with COVID-19, 74.5% were aged ≥50 years, and 54.4% were male. The hospitalization rate among patients identified through COVID-NET during this 4-week period was 4.6 per 100,000 population. Rates were highest (13.8) among adults aged ≥65 years. Among 178 (12%) adult patients with data on underlying conditions as of March 30, 2020, 89.3% had one or more underlying conditions; the most common were hypertension (49.7%), obesity (48.3%), chronic lung disease (34.6%), diabetes mellitus (28.3%), and cardiovascular disease (27.8%). These findings suggest that older adults have elevated rates of COVID-19-associated hospitalization and the majority of persons hospitalized with COVID-19 have underlying medical conditions. These findings underscore the importance of preventive measures (e.g., social distancing, respiratory hygiene, and wearing face coverings in public settings where social distancing measures are difficult to maintain) † to protect older adults and persons with underlying medical conditions, as well as the general public. In addition, older adults and persons with serious underlying medical conditions should avoid contact with persons who are ill and immediately contact their health care provider(s) if they have symptoms consistent with COVID-19 (https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/symptoms.html) (5). Ongoing monitoring of hospitalization rates, clinical characteristics, and outcomes of hospitalized patients will be important to better understand the evolving epidemiology of COVID-19 in the United States and the clinical spectrum of disease, and to help guide planning and prioritization of health care system resources., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Linda Niccolai reports personal fees from Merck outside the submitted work; Evan Anderson reports personal fees from AbbVie and Pfizer, and grants from MedImmune, Regeneron, PaxVax, Pfizer, GSK, Merck, Novavax, Sanofi-Pasteur, and Micron, outside the submitted work; Andrew Weigel reports grants from the Council of State and Territorial Epidemiologists during the conduct of the study; Ruth Lynfield reports that she is the coeditor for a book on public health and an associate editor for American Academy of Pediatrics Report of the Committee of Infectious Diseases (Red Book); Laurie Billing reports a grant from the Council of State and Territorial Epidemiologists during the conduct of the study; William Schaffner reports personal fees from Pfizer, Roche Diagnostics, and Pepsico outside the submitted work; H. Keipp Talbot reports compensation from Seqiris outside the submitted work; Andrea George reports a grant from the Council of State and Territorial Epidemiologists during the conduct of the study; Sue Kim reports a grant from the Council of State and Territorial Epidemiologists during the conduct of the study; Justin Henderson reports a grant from the Council of State and Territorial Epidemiologists during the conduct of the study; and Clarissa Aquino reports a grant from the Council of State and Territorial Epidemiologists during the conduct of the study. No other potential conflicts of interest were disclosed.

During August 1, 2014-July 31, 2015, in 2 counties in Minnesota, USA, incidence of invasive methicillin-susceptible Staphylococcus aureus (MSSA) (27.1 cases/100,000 persons) was twice that of invasive methicillin-resistant S. aureus (13.1 cases/100,000 persons). MSSA isolates were more genetically diverse and susceptible to more antimicrobial drugs than methicillin-resistant S. aureus isolates.

Background: Existing literature suggests that influenza C typically causes mild respiratory tract disease. However, clinical and epidemiological data are limited., Methods: Four outpatient clinics and 3 hospitals submitted clinical data and respiratory specimens through a surveillance network for acute respiratory infection (ARI) from May 2013 through December 2016. Specimens were tested using multitarget nucleic acid amplification for 19-22 respiratory pathogens, including influenza C., Results: Influenza C virus was detected among 59 of 10 202 (0.58%) hospitalized severe ARI cases and 11 of 2282 (0.48%) outpatients. Most detections occurred from December to March, 73% during the 2014-2015 season. Influenza C detections occurred among patients of all ages, with rates being similar between inpatients and outpatients. The highest rate of detection occurred among children aged 6-24 months (1.2%). Among hospitalized cases, 7 required intensive care. Medical comorbidities were reported in 58% of hospitalized cases and all who required intensive care. At least 1 other respiratory pathogen was detected in 40 (66%) cases, most commonly rhinovirus/enterovirus (25%) and respiratory syncytial virus (20%). The hemagglutinin-esterase-fusion gene was sequenced in 37 specimens, and both C/Kanagawa and C/Sao Paulo lineages were detected in inpatients and outpatients., Conclusions: We found seasonal circulation of influenza C with year-to-year variability. Detection was most frequent among young children but occurred in all ages. Some cases that were positive for influenza C, particularly those with comorbid conditions, had severe disease, suggesting a need for further study of the role of influenza C virus in the pathogenesis of respiratory disease.

On April 10, 2017, the Minnesota Department of Health (MDH) was notified about a suspected measles case. The patient was a hospitalized child aged 25 months who was evaluated for fever and rash, with onset on April 8. The child had no history of receipt of measles-mumps-rubella (MMR) vaccine and no travel history or known exposure to measles. On April 11, MDH received a report of a second hospitalized, unvaccinated child, aged 34 months, with an acute febrile rash illness with onset on April 10. The second patient's sibling, aged 19 months, who had also not received MMR vaccine, had similar symptoms, with rash onset on March 30. Real-time reverse transcription-polymerase chain reaction (rRT-PCR) testing of nasopharyngeal swab or throat specimens performed at MDH confirmed measles in the first two patients on April 11, and in the third patient on April 13; subsequent genotyping identified genotype B3 virus in all three patients, who attended the same child care center. MDH instituted outbreak investigation and response activities in collaboration with local health departments, health care facilities, child care facilities, and schools in affected settings. Because the outbreak occurred in a community with low MMR vaccination coverage, measles spread rapidly, resulting in thousands of exposures in child care centers, schools, and health care facilities. By May 31, 2017, a total of 65 confirmed measles cases had been reported to MDH (Figure 1); transmission is ongoing.

Background: Invasive group A Streptococcus (iGAS) infections cause significant morbidity and mortality worldwide. We analyzed whether obesity and diabetes were associated with iGAS infections and worse outcomes among an adult US population., Methods: We determined the incidence of iGAS infections using 2010-2012 cases in adults aged ≥ 18 years from Active Bacterial Core surveillance (ABCs), a population-based surveillance system, as the numerator. For the denominator, we used ABCs catchment area population estimates from the 2011 to 2012 Behavioral Risk Factor Surveillance System (BRFSS) survey. The relative risk (RR) of iGAS was determined by obesity and diabetes status after adjusting for age group, gender, race, and other underlying conditions through binomial logistic regression. Multivariable logistic regression was used to determine whether obesity or diabetes was associated with increased odds of death due to iGAS compared to normal weight and nondiabetic patients, respectively., Results: Between 2010 and 2012, 2927 iGAS cases were identified. Diabetes was associated with an increased risk of iGAS in all racial groups (adjusted risk ratio [aRR] ranged from 2.71 to 5.08). Grade 3 obesity (body mass index [BMI] ≥ 40) was associated with an increased risk of iGAS for whites (aRR = 3.47; 95% confidence interval [CI], 3.00-4.01). Grades 1-2 (BMI = 30.0-<40.0) and grade 3 obesity were associated with an increased odds of death (odds ratio [OR] = 1.55, [95% CI, 1.05, 2.29] and OR = 1.62 [95% CI, 1.01, 2.61], respectively) when compared to normal weight patients., Conclusions: These results may help target vaccines against GAS that are currently under development. Efforts to develop enhanced treatment regimens for iGAS may improve prognoses for obese patients., (Published by Oxford University Press for the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Tracking of infectious diseases is a public health core function essential to disease prevention and control. Each state mandates reporting of certain infectious diseases to public health authorities. These laws vary by state, and the variation could affect the ability to collect critical information. The 2009 H1N1 influenza pandemic served as a case study to examine the legal authority in the 50 states; Washington, DC; and New York City for mandatory infectious disease reporting, particularly for influenza and new or emerging infectious diseases. Our study showed reporting laws to be generally present and functioning well; nevertheless, jurisdictions should be mindful of their mandated parameters and review the robustness of their laws before they face a new or emerging disease outbreak.

Background: The objective of this study is to determine the costs per hospital admission of screening intensive care unit patients for methicillin-resistant Staphylococcus aureus (MRSA) and isolating those who are colonized., Methods: Data on the costs of the intervention come from the Minneapolis Veterans Affairs Medical Center, a 279-bed teaching hospital and outpatient facility. A microcosting approach is used to determine the intervention costs for 3 different laboratory testing protocols. The costs of caring for MRSA-infected patients come from the experience of 241 Minneapolis Veterans Affairs Medical Center patients with MRSA infections in 2004 through 2006. The effectiveness of the intervention comes from the extant literature. To capture the effect of screening on reducing transmission of MRSA to other patients and its effect on costs, a Markov simulation model was employed., Results: The intervention was cost saving compared with no intervention for all 3 laboratory processes evaluated and for all of the 1-way sensitivity analyses considered., Conclusion: Because of the high cost of caring for a MRSA patient, interventions that reduce the spread of infections-such as screening intensive care unit patients upon admission studied here-are likely to pay for themselves., (Copyright © 2011 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.)

Prior to 2009, influenza pandemic planners had primarily planned for a virus that would originate in a location other than North America, giving public health officials in the United States time to determine its severity before widespread disease occurred here. Thus, response plans for schools focused on closure in the case of a severe pandemic and potential closure in the event of a moderate one. The 2009 H1N1 pandemic, however, presented a different scenario. The severity of 2009 H1N1 was initially unknown and later was determined to be mild to moderate. Thus, as the pandemic unfolded, state and national public health entities found themselves adapting their recommendations for school closure. This article reviews Minnesota's experience with 2009 H1N1, focusing on the pandemic among school-aged children during the spring (April to August 2009) and fall (September 2009 to April 2010), and it chronicles how outbreak surveillance policies and recommendations for K-12 schools changed over the course of the pandemic.