Adverse outcomes of SARS-CoV-2 infection with delta and omicron variants in vaccinated versus unvaccinated US veterans: retrospective cohort study.

OBJECTIVES: To determine the association between covid-19 vaccination types and doses with adverse outcomes of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection during the periods of delta (B.1.617.2) and omicron (B.1.1.529) variant predominance. DESIGN: Retrospective cohort. SETTING: US Veterans Affairs healthcare system. PARTICIPANTS: Adults (≥18 years) who are affiliated to Veterans Affairs with a first documented SARS-CoV-2 infection during the periods of delta (1 July-30 November 2021) or omicron (1 January-30 June 2022) variant predominance. The combined cohorts had a mean age of 59.4 (standard deviation 16.3) and 87% were male. INTERVENTIONS: Covid-19 vaccination with mRNA vaccines (BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna)) and adenovirus vector vaccine (Ad26.COV2.S (Janssen/Johnson & Johnson)). MAIN OUTCOME MEASURES: Stay in hospital, intensive care unit admission, use of ventilation, and mortality measured 30 days after a positive test result for SARS-CoV-2. RESULTS: In the delta period, 95 336 patients had infections with 47.6% having at least one vaccine dose, compared with 184 653 patients in the omicron period, with 72.6% vaccinated. After adjustment for patient demographic and clinical characteristics, in the delta period, two doses of the mRNA vaccines were associated with lower odds of hospital admission (adjusted odds ratio 0.41 (95% confidence interval 0.39 to 0.43)), intensive care unit admission (0.33 (0.31 to 0.36)), ventilation (0.27 (0.24 to 0.30)), and death (0.21 (0.19 to 0.23)), compared with no vaccination. In the omicron period, receipt of two mRNA doses were associated with lower odds of hospital admission (0.60 (0.57 to 0.63)), intensive care unit admission (0.57 (0.53 to 0.62)), ventilation (0.59 (0.51 to 0.67)), and death (0.43 (0.39 to 0.48)). Additionally, a third mRNA dose was associated with lower odds of all outcomes compared with two doses: hospital admission (0.65 (0.63 to 0.69)), intensive care unit admission (0.65 (0.59 to 0.70)), ventilation (0.70 (0.61 to 0.80)), and death (0.51 (0.46 to 0.57)). The Ad26.COV2.S vaccination was associated with better outcomes relative to no vaccination, but higher odds of hospital stay and intensive care unit admission than with two mRNA doses. BNT162b2 was generally associated with worse outcomes than mRNA-1273 (adjusted odds ratios between 0.97 and 1.42). CONCLUSIONS: In veterans with recent healthcare use and high occurrence of multimorbidity, vaccination was robustly associated with lower odds of 30 day morbidity and mortality compared with no vaccination among patients infected with covid-19. The vaccination type and number of doses had a significant association with outcomes.

Prevalence and Causes of Diagnostic Errors in Hospitalized Patients Under Investigation for COVID-19.

BACKGROUND: The COVID-19 pandemic required clinicians to care for a disease with evolving characteristics while also adhering to care changes (e.g., physical distancing practices) that might lead to diagnostic errors (DEs). OBJECTIVE: To determine the frequency of DEs and their causes among patients hospitalized under investigation (PUI) for COVID-19. DESIGN: Retrospective cohort. SETTING: Eight medical centers affiliated with the Hospital Medicine ReEngineering Network (HOMERuN). TARGET POPULATION: Adults hospitalized under investigation (PUI) for COVID-19 infection between February and July 2020. MEASUREMENTS: We randomly selected up to 8 cases per site per month for review, with each case reviewed by two clinicians to determine whether a DE (defined as a missed or delayed diagnosis) occurred, and whether any diagnostic process faults took place. We used bivariable statistics to compare patients with and without DE and multivariable models to determine which process faults or patient factors were associated with DEs. RESULTS: Two hundred and fifty-seven patient charts underwent review, of which 36 (14%) had a diagnostic error. Patients with and without DE were statistically similar in terms of socioeconomic factors, comorbidities, risk factors for COVID-19, and COVID-19 test turnaround time and eventual positivity. Most common diagnostic process faults contributing to DE were problems with clinical assessment, testing choices, history taking, and physical examination (all p < 0.01). Diagnostic process faults associated with policies and procedures related to COVID-19 were not associated with DE risk. Fourteen patients (35.9% of patients with errors and 5.4% overall) suffered harm or death due to diagnostic error. LIMITATIONS: Results are limited by available documentation and do not capture communication between providers and patients. CONCLUSION: Among PUI patients, DEs were common and not associated with pandemic-related care changes, suggesting the importance of more general diagnostic process gaps in error propagation.

Comparison of the Impact of COVID-19 on Veterans Affairs and Non-federal Hospitals: a Survey of Infection Prevention Specialists.

BACKGROUND: As the COVID-19 pandemic evolves, it is critical to understand characteristics that have allowed US healthcare systems, including the Veterans Affairs (VA) and non-federal hospitals, to mount an effective response in the setting of limited resources and unpredictable clinical demands generated by this system shock. OBJECTIVE: To compare the impact of and response to resource shortages to both VA and non-federal healthcare systems during the COVID-19 pandemic. DESIGN: Cross-sectional national survey administered April 2021 through May 2022. PARTICIPANTS: Lead infection preventionists from VA and non-federal hospitals across the US. MAIN MEASURES: Surveys collected hospital demographic factors along with 11 questions aimed at assessing the effectiveness of the hospital's COVID response. KEY RESULTS: The response rate was 56% (71/127) from VA and 47% (415/881) from non-federal hospitals. Compared to VA hospitals, non-federal hospitals had a larger average number of acute care (214 vs. 103 beds, p<.001) and intensive care unit (24 vs. 16, p<.001) beds. VA hospitals were more likely to report no shortages of personal protective equipment or medical supplies during the pandemic (17% vs. 9%, p=.03) and more frequently opened new units to care specifically for COVID patients (71% vs. 49%, p<.001) compared with non-federal hospitals. Non-federal hospitals more frequently experienced increased loss of staff due to resignations (76% vs. 53%, p=.001) and financial hardships stemming from the pandemic (58% vs. 7%, p<0.001). CONCLUSIONS: In our survey-based national study, lead infection preventionists noted several distinct advantages in VA versus non-federal hospitals in their ability to expand bed capacity, retain staff, mitigate supply shortages, and avoid financial hardship. While these benefits appear to be inherent to the VA's structure, non-federal hospitals can adapt their infrastructure to better weather future system shocks.

Identifying Strategies to Boost COVID-19 Vaccine Acceptance in the United States

This study presents the results of an evaluation of the root causes of COVID-19 vaccine hesitancy to inform strategies to boost vaccine acceptance among vaccine-hesitant populations in the United States. The authors conducted a literature review of the causes of vaccine hesitancy and vaccine acceptance;focus groups with patients, pre-hospital first responders, and hospital-based health care providers;a social media platform sentiment analysis to review attitudes regarding the COVID-19 vaccine;and a roundtable discussion with experts on vaccine hesitancy. Drawing on this mixed-methods analysis, the authors recommend strategies to help boost COVID-19 vaccine acceptance in the United States, grouping them according to three overall goals: boosting confidence in the safety and effectiveness of the COVID-19 vaccines, combating complacency about the pandemic, and increasing the convenience of getting vaccinated. The authors emphasize that combating misinformation about the COVID-19 vaccine is key to achieving these goals. These recommendations can inform the development of a toolkit of strategies to reach herd immunity and end the pandemic.

Vaccine breakthrough infections in veterans hospitalized with coronavirus infectious disease-2019: A case series.

BACKGROUND: While Severe Acute Respiratory Syndrome Coronavirus-2 vaccine breakthrough infections are expected, reporting on breakthrough infections requiring hospitalization remains limited. This observational case series report reviewed 10 individuals hospitalized with vaccine breakthrough infections to identify patient risk factors and serologic responses upon admission. METHODS: Electronic medical records of BNT162b2 (Pfizer-BioNTech) or mRNA-1732 (Moderna) vaccinated patients admitted to Veterans Affairs Ann Arbor Healthcare System with newly diagnosed Coronavirus Infectious Disease 2019 (COVID-19) between March 15, 2021 and April 15, 2021 were reviewed. Patient variables, COVID-19 lab testing including anti-S IgM, anti-N IgG antibodies, and hospital course were recorded. Based on lab testing, infections were defined as acute infection or resolving/resolved infection. RESULTS: Of the 10 patients admitted with breakthrough infections, all were >70 years of age with multiple comorbidities. Mean time between second vaccine dose and COVID-19 diagnosis was 49 days. In the 7 individuals with acute infection, none had observed serologic response to mRNA vaccination, 5 developed severe disease, and 1 died. Three individuals had anti-N IgG antibodies and a high polymerase chain reaction cycle threshold value, suggesting resolving/resolved infection. CONCLUSIONS: Given the variability of vaccine breakthrough infections requiring hospitalization, serologic testing may impart clarity on timing of infection and disease prognosis. Individuals at risk of diminished response to vaccines and severe COVID-19 may also benefit from selective serologic testing after vaccination to guide risk mitigation strategies in a post-pandemic environment.