AbstractObjectivesTo characterize the clinical severity of covid-19 associated with the alpha, delta, and omicron SARS-CoV-2 variants among adults admitted to hospital and to compare the ...effectiveness of mRNA vaccines to prevent hospital admissions related to each variant.DesignCase-control study.Setting21 hospitals across the United States.Participants11 690 adults (≥18 years) admitted to hospital: 5728 with covid-19 (cases) and 5962 without covid-19 (controls). Patients were classified into SARS-CoV-2 variant groups based on viral whole genome sequencing, and, if sequencing did not reveal a lineage, by the predominant circulating variant at the time of hospital admission: alpha (11 March to 3 July 2021), delta (4 July to 25 December 2021), and omicron (26 December 2021 to 14 January 2022).Main outcome measuresVaccine effectiveness calculated using a test negative design for mRNA vaccines to prevent covid-19 related hospital admissions by each variant (alpha, delta, omicron). Among patients admitted to hospital with covid-19, disease severity on the World Health Organization’s clinical progression scale was compared among variants using proportional odds regression.ResultsEffectiveness of the mRNA vaccines to prevent covid-19 associated hospital admissions was 85% (95% confidence interval 82% to 88%) for two vaccine doses against the alpha variant, 85% (83% to 87%) for two doses against the delta variant, 94% (92% to 95%) for three doses against the delta variant, 65% (51% to 75%) for two doses against the omicron variant; and 86% (77% to 91%) for three doses against the omicron variant. In-hospital mortality was 7.6% (81/1060) for alpha, 12.2% (461/3788) for delta, and 7.1% (40/565) for omicron. Among unvaccinated patients with covid-19 admitted to hospital, severity on the WHO clinical progression scale was higher for the delta versus alpha variant (adjusted proportional odds ratio 1.28, 95% confidence interval 1.11 to 1.46), and lower for the omicron versus delta variant (0.61, 0.49 to 0.77). Compared with unvaccinated patients, severity was lower for vaccinated patients for each variant, including alpha (adjusted proportional odds ratio 0.33, 0.23 to 0.49), delta (0.44, 0.37 to 0.51), and omicron (0.61, 0.44 to 0.85).ConclusionsmRNA vaccines were found to be highly effective in preventing covid-19 associated hospital admissions related to the alpha, delta, and omicron variants, but three vaccine doses were required to achieve protection against omicron similar to the protection that two doses provided against the delta and alpha variants. Among adults admitted to hospital with covid-19, the omicron variant was associated with less severe disease than the delta variant but still resulted in substantial morbidity and mortality. Vaccinated patients admitted to hospital with covid-19 had significantly lower disease severity than unvaccinated patients for all the variants.
In this study evaluating BNT162b2, vaccine effectiveness against hospitalization for Covid-19 in the delta-predominant period among adolescents 12 to 18 years of age was more than 90%; during the ...omicron period, vaccine effectiveness was 40% against hospitalization and 79% against critical illness. Vaccine effectiveness against hospitalization was 68% among children 5 to 11 years of age.
Investigators used a case–control, test-negative design to assess the effectiveness of the BNT162b2 vaccine in adolescents for the prevention of Covid-19–related hospitalization, ICU admission, or ...receipt of life support. Among 445 case patients and 777 controls, of the 180 patients admitted to an ICU, only 2 had been fully vaccinated; all 7 deaths occurred in unvaccinated patients.
Abstract
Background
Influenza causes significant morbidity and mortality and stresses hospital resources during periods of increased circulation. We evaluated the effectiveness of the 2019–2020 ...influenza vaccine against influenza-associated hospitalization in the United States.
Methods
We included adults hospitalized with acute respiratory illness at 14 hospitals and tested for influenza viruses by reserve-transcription polymerase chain reaction. Vaccine effectiveness (VE) was estimated by comparing the odds of current-season influenza vaccination in test-positive influenza cases vs test-negative controls, adjusting for confounders. VE was stratified by age and major circulating influenza types along with A(H1N1)pdm09 genetic subgroups.
Results
A total of 3116 participants were included, including 18% (n = 553) influenza-positive cases. Median age was 63 years. Sixty-seven percent (n = 2079) received vaccination. Overall adjusted VE against influenza viruses was 41% (95% confidence interval CI, 27%–52%). VE against A(H1N1)pdm09 viruses was 40% (95% CI, 24%–53%) and 33% against B viruses (95% CI, 0–56%). Of the 2 major A(H1N1)pdm09 subgroups (representing 90% of sequenced H1N1 viruses), VE against one group (5A + 187A,189E) was 59% (95% CI, 34%–75%) whereas no VE was observed against the other group (5A + 156K) (–1% 95% CI, –61% to 37%).
Conclusions
In a primarily older population, influenza vaccination was associated with a 41% reduction in risk of hospitalized influenza illness.
During the 2019-2020 United States influenza season, genetically diverse influenza A(H1N1)pdm09 and influenza B viruses of the Victoria lineage co-circulated. Overall vaccine effectiveness against influenza-associated hospitalization was 41% despite circulation of multiple antigenically drifted viruses.
Abstract
Background
As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination coverage increases in the United States, there is a need to understand the real-world effectiveness ...against severe coronavirus disease 2019 (COVID-19) and among people at increased risk for poor outcomes.
Methods
In a multicenter case-control analysis of US adults hospitalized March 11–May 5, 2021, we evaluated vaccine effectiveness to prevent COVID-19 hospitalizations by comparing odds of prior vaccination with a messenger RNA (mRNA) vaccine (Pfizer-BioNTech or Moderna) between cases hospitalized with COVID-19 and hospital-based controls who tested negative for SARS-CoV-2.
Results
Among 1212 participants, including 593 cases and 619 controls, median age was 58 years, 22.8% were Black, 13.9% were Hispanic, and 21.0% had immunosuppression. SARS-CoV-2 lineage B0.1.1.7 (Alpha) was the most common variant (67.9% of viruses with lineage determined). Full vaccination (receipt of 2 vaccine doses ≥14 days before illness onset) had been received by 8.2% of cases and 36.4% of controls. Overall vaccine effectiveness was 87.1% (95% confidence interval CI, 80.7–91.3). Vaccine effectiveness was similar for Pfizer-BioNTech and Moderna vaccines, and highest in adults aged 18–49 years (97.4%; 95% CI, 79.3–9.7). Among 45 patients with vaccine-breakthrough COVID hospitalizations, 44 (97.8%) were ≥50 years old and 20 (44.4%) had immunosuppression. Vaccine effectiveness was lower among patients with immunosuppression (62.9%; 95% CI,20.8–82.6) than without immunosuppression (91.3%; 95% CI, 85.6–94.8).
Conclusion
During March–May 2021, SARS-CoV-2 mRNA vaccines were highly effective for preventing COVID-19 hospitalizations among US adults. SARS-CoV-2 vaccination was beneficial for patients with immunosuppression, but effectiveness was lower in the immunosuppressed population.
From March to May 2021, full vaccination using authorized mRNA products was associated with 87.1% (95% CI, 80.7–91.3) protection against COVID-19 hospitalization among US adults. Vaccine effectiveness was lower in adults with versus without immunosuppression (62.9% versus 91.3%).
Abstract Background Influenza remains an important cause of hospitalizations in the United States. Estimating the number of influenza hospitalizations is vital for public health decision making. ...Combining existing surveillance systems through capture-recapture methods allows for more comprehensive burden estimations. Methods Data from independent surveillance systems were combined using capture-recapture methods to estimate influenza hospitalization rates for children and adults in Middle Tennessee during consecutive influenza seasons from 2016–2017 through 2019–2020. The Emerging Infections Program (EIP) identified cases through surveillance of laboratory results for hospitalized children and adults. The Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN) and New Vaccine Surveillance Network (NVSN) recruited hospitalized patients with respiratory symptoms or fever. Population-based influenza rates and the proportion of cases detected by each surveillance system were calculated. Results Estimated overall influenza hospitalization rates ranged from 23 influenza-related hospitalizations per 10 000 persons in 2016–2017 to 40 per 10 000 persons in 2017–2018. Adults aged ≥65 years had the highest hospitalization rates across seasons and experienced a rate of 170 hospitalizations per 10 000 persons during the 2017–2018 season. EIP consistently identified a higher proportion of influenza cases for adults and children compared with HAIVEN and NVSN, respectively. Conclusions Current surveillance systems underestimate the influenza burden. Capture-recapture provides an alternative approach to use data from independent surveillance systems and complement population-based burden estimates.
In 2017, we conducted a multistate investigation to determine the source of an outbreak of Shiga toxin-producing
(STEC) O157:H7 infections, which occurred primarily in children.
We defined a case as ...infection with an outbreak strain of STEC O157:H7 with illness onset between January 1, 2017, and April 30, 2017. Case patients were interviewed to identify common exposures. Traceback and facility investigations were conducted; food samples were tested for STEC.
We identified 32 cases from 12 states. Twenty-six (81%) cases occurred in children <18 years old; 8 children developed hemolytic uremic syndrome. Twenty-five (78%) case patients ate the same brand of soy nut butter or attended facilities that served it. We identified 3 illness subclusters, including a child care center where person-to-person transmission may have occurred. Testing isolated an outbreak strain from 11 soy nut butter samples. Investigations identified violations of good manufacturing practices at the soy nut butter manufacturing facility with opportunities for product contamination, although the specific route of contamination was undetermined.
This investigation identified soy nut butter as the source of a multistate outbreak of STEC infections affecting mainly children. The ensuing recall of all soy nut butter products the facility manufactured, totaling >1.2 million lb, likely prevented additional illnesses. Prompt diagnosis of STEC infections and appropriate specimen collection aids in outbreak detection. Child care providers should follow appropriate hygiene practices to prevent secondary spread of enteric illness in child care settings. Firms should manufacture ready-to-eat foods in a manner that minimizes the risk of contamination.
To evaluate whether providing resident physicians with "DOCTOR" role identification badges would impact perceptions of bias in the workforce and alter misidentification rates.
Between October 2019 ...and December 2019, we surveyed 341 resident physicians in the anesthesiology, dermatology, internal medicine, neurologic surgery, otorhinolaryngology, and urology departments at Mayo Clinic in Rochester, Minnesota, before and after an 8-week intervention of providing "DOCTOR" role identification badges. Differences between paired preintervention and postintervention survey answers were measured, with a focus on the frequency of experiencing perceived bias and role misidentification (significance level, α=.01). Free-text comments were also compared.
Of the 159 residents who returned both the before and after surveys (survey response rate, 46.6% 159 of 341), 128 (80.5%) wore the "DOCTOR" badge. After the intervention, residents who wore the badges were statistically significantly less likely to report role misidentification at least once a week from patients, nonphysician team members, and other physicians (50.8% 65 preintervention vs 10.2% 13 postintervention; 35.9% 46 vs 8.6% 11; 18.0% 23 vs 3.9% 5, respectively; all P<.001). The 66 female residents reported statistically significantly fewer episodes of gender bias (65.2% 43 vs 31.8% 21; P<.001). The 13 residents who identified as underrepresented in medicine reported statistically significantly less misidentification from patients (84.6% 11 vs 23.1% 3; P=.008); although not a statistically significant difference, the 13 residents identifying as underrepresented in medicine also reported less misidentification with nonphysician team members (46.2% 6 vs 15.4% 2; P=.13).
Residents reported decreased role misidentification after use of a role identification badge, most prominently improved among women. Decreasing workplace bias is essential in efforts to improve both diversity and inclusion efforts in training programs.
IMPORTANCE: Influenza virus infection during pregnancy is associated with severe maternal disease and may be associated with adverse birth outcomes. Inactivated influenza vaccine during pregnancy is ...safe and effective and can protect young infants, but recent evidence, particularly after the 2009 novel influenza A (H1N1) pandemic, is limited. OBJECTIVE: To evaluate the effectiveness of influenza vaccination during pregnancy against laboratory-confirmed influenza-associated hospitalizations and emergency department (ED) visits in infants younger than 6 months. DESIGN, SETTING, AND PARTICIPANTS: This was a prospective, test-negative case-control study using data from the New Vaccine Surveillance Network from the 2016 to 2017 through 2019 to 2020 influenza seasons. Infants younger than 6 months with an ED visit or hospitalization for acute respiratory illness were included from 7 pediatric medical institutions in US cities. Control infants with an influenza-negative molecular test were included for comparison. Data were analyzed from June 2022 to September 2023. EXPOSURE: Maternal influenza vaccination during pregnancy. MAIN OUTCOMES AND MEASURES: We estimated maternal vaccine effectiveness against hospitalizations or ED visits in infants younger than 6 months, those younger than 3 months, and by trimester of vaccination. Maternal vaccination status was determined using immunization information systems, medical records, or self-report. Vaccine effectiveness was estimated by comparing the odds of maternal influenza vaccination 14 days or more before delivery in infants with influenza vs those without. RESULTS: Of 3764 infants (223 with influenza and 3541 control infants), 2007 (53%) were born to mothers who were vaccinated during pregnancy. Overall vaccine effectiveness in infants was 34% (95% CI, 12 to 50), 39% (95% CI, 12 to 58) against influenza-associated hospitalizations, and 19% (95% CI, −24 to 48) against ED visits. Among infants younger than 3 months, effectiveness was 53% (95% CI, 30 to 68). Effectiveness was 52% (95% CI, 30 to 68) among infants with mothers who were vaccinated during the third trimester and 17% (95% CI, −15 to 40) among those with mothers who were vaccinated during the first or second trimesters. CONCLUSIONS AND RELEVANCE: Maternal vaccination was associated with reduced odds of influenza-associated hospitalizations and ED visits in infants younger than 6 months. Effectiveness was greatest among infants younger than 3 months, for those born to mothers vaccinated during the third trimester, and against influenza-associated hospitalizations.