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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22278552

RESUMO

Neutralizing antibody plays a key role in protective immunity against COVID-19. As increasingly distinct variants circulate, debate continues regarding the value of adding novel variants to SARS-CoV-2 vaccines. In this study, we have analyzed live virus neutralization titers against WA1, Delta, BA.1, BA.2, and BA.5 in 187 hospitalized patients infected with Delta or Omicron strains. This information will be useful in selection of the SARS-CoV-2 strains to include in an updated vaccine. Our results show that unvaccinated Delta infected patients made a highly biased neutralizing antibody response towards the infecting Delta strain with slightly lower responses against the WA1 strain, but with strikingly lower titers against BA.1, BA.2, and BA.5. Delta infected patients that had been previously vaccinated with the WA1 containing COVID vaccine made equivalent responses to WA1 and Delta strains, but still had very low neutralizing antibody responses to Omicron strains. In striking contrast, both unvaccinated and vaccinated Omicron patients exhibited a more balanced ratio of Omicron virus neutralization compared to neutralization of ancestral strains. Interestingly, Omicron patients infected with BA.1 or BA.2 had detectable neutralizing antibody titers to BA.5, but these titers were lower than neutralization titers to BA.1 and BA.2. Taken together, these results suggest that inclusion of the Omicron BA.5 strain in a SARS-CoV-2 vaccine would be beneficial in protection against the widely circulating BA.5 variant. DisclaimerThe findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22276228

RESUMO

Objectives: To compare the effectiveness of a primary COVID-19 vaccine series plus a booster dose with a primary series alone for the prevention of Omicron variant COVID-19 hospitalization. Design: Multicenter observational case-control study using the test-negative design to evaluate vaccine effectiveness (VE). Setting: Twenty-one hospitals in the United States (US). Participants: 3,181 adults hospitalized with an acute respiratory illness between December 26, 2021 and April 30, 2022, a period of SARS-CoV-2 Omicron variant (BA.1, BA.2) predominance. Participants included 1,572 (49%) case-patients with laboratory confirmed COVID-19 and 1,609 (51%) control patients who tested negative for SARS-CoV-2. Median age was 64 years, 48% were female, and 21% were immunocompromised; 798 (25%) were vaccinated with a primary series plus booster, 1,326 (42%) were vaccinated with a primary series alone, and 1,057 (33%) were unvaccinated. Main Outcome Measures: VE against COVID-19 hospitalization was calculated for a primary series plus a booster and a primary series alone by comparing the odds of being vaccinated with each of these regimens versus being unvaccinated among cases versus controls. VE analyses were stratified by immune status (immunocompetent; immunocompromised) because the recommended vaccine schedules are different for these groups. The primary analysis evaluated all COVID-19 vaccine types combined and secondary analyses evaluated specific vaccine products. Results: Among immunocompetent patients, VE against Omicron COVID-19 hospitalization for a primary series plus one booster of any vaccine product dose was 77% (95% CI: 71-82%), and for a primary series alone was 44% (95% CI: 31-54%) (p<0.001). VE was higher for a boosted regimen than a primary series alone for both mRNA vaccines used in the US (BNT162b2: primary series plus booster VE 80% (95% CI: 73-85%), primary series alone VE 46% (95% CI: 30-58%) [p<0.001]; mRNA-1273: primary series plus booster VE 77% (95% CI: 67-83%), primary series alone VE 47% (95% CI: 30-60%) [p<0.001]). Among immunocompromised patients, VE for a primary series of any vaccine product against Omicron COVID-19 hospitalization was 60% (95% CI: 41-73%). Insufficient sample size has accumulated to calculate effectiveness of boosted regimens for immunocompromised patients. Conclusions: Among immunocompetent people, a booster dose of COVID-19 vaccine provided additional benefit beyond a primary vaccine series alone for preventing COVID-19 hospitalization due to the Omicron variant.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22271092

RESUMO

AO_SCPLOWBSTRACTC_SCPLOWO_ST_ABSImportanceC_ST_ABSAlthough COVID-19 vaccines protect against infection and severe disease, the role of vaccination in preventing prolonged symptoms in those with subsequent infection is unclear. ObjectiveTo determine differences in symptoms stratified by prior vaccination reported by healthcare personnel (HCP) 6 weeks after onset of COVID-19, and whether there were differences in timing of return to work. DesignNested cohort study within a multicenter vaccine effectiveness study. HCP with COVID-19 between December 2020 and August 2021 were followed up 6 weeks after illness onset. SettingHealth systems in 12 U.S. states. ParticipantsHCP participating in a vaccine effectiveness study were eligible for inclusion if they had confirmed COVID-19 with either verified mRNA vaccination (symptom onset [≥]14 days after two doses) or no prior COVID-19 vaccination. Among 681 eligible participants, 419 (61%) completed a follow-up survey approximately 6 weeks after illness onset. ExposuresTwo doses of a COVID-19 mRNA vaccine compared with no COVID-19 vaccine. Main outcomes and measuresPresence of symptoms 6 weeks after onset of COVID-19 illness and days to return to work after COVID-19 illness. ResultsAmong 419 HCP with confirmed COVID-19, 298 (71%) reported one or more COVID-like symptoms 6 weeks after illness onset, with a lower prevalence among vaccinated participants (60.6%) compared with unvaccinated participants (60.6% vs. 79.1%; aRR 0.70, 95% CI 0.58-0.84). Vaccinated HCP returned to work a median 2.0 days (95% CI 1.0-3.0) sooner than unvaccinated HCP (aHR 1.37; 95% CI, 1.04-1.79). ConclusionsA history of two doses of COVID-19 mRNA vaccine among HCP with COVID-19 illness was associated with decreased risk of COVID-like symptoms at 6 weeks and earlier to return to work. Vaccination is associated with improved recovery from COVID-19, in addition to preventing symptomatic infection. KEY POINTSO_ST_ABSQuestionC_ST_ABSDoes vaccination lead to improved recovery of symptoms and return to work following COVID-19? FindingsIn this nested cohort study of healthcare personnel, participants with COVID-19 who had received two doses of a COVID-19 mRNA vaccine were less likely to report symptoms 6 weeks after illness onset than participants with COVID-19 who were unvaccinated. Return to work was sooner if previously vaccinated. MeaningVaccination is associated with improved recovery from COVID-19, in addition to prevention of infection and disease.

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22270558

RESUMO

ObjectivesTo characterize the clinical severity of COVID-19 caused by Omicron, Delta, and Alpha SARS-CoV-2 variants among hospitalized adults and to compare the effectiveness of mRNA COVID-19 vaccines to prevent hospitalizations caused by each variant. DesignA case-control study of 11,690 hospitalized adults. SettingTwenty-one hospitals across the United States. ParticipantsThis study included 5728 cases hospitalized with COVID-19 and 5962 controls hospitalized without COVID-19. Cases 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 (March 11 to July 3, 2021), Delta (July 4 to December 25, 2021), and Omicron (December 26, 2021 to January 14, 2022). Main Outcome MeasuresVaccine effectiveness was calculated using a test-negative design for COVID-19 mRNA vaccines to prevent COVID-19 hospitalizations by each variant (Alpha, Delta, Omicron). Among hospitalized patients with COVID-19, disease severity on the WHO Clinical Progression Ordinal Scale was compared among variants using proportional odds regression. ResultsVaccine effectiveness of the mRNA vaccines to prevent COVID-19-associated hospitalizations included: 85% (95% CI: 82 to 88%) for 2 vaccine doses against Alpha; 85% (95% CI: 83 to 87%) for 2 doses against Delta; 94% (95% CI: 92 to 95%) for 3 doses against Delta; 65% (95% CI: 51 to 75%) for 2 doses against Omicron; and 86% (95% CI: 77 to 91%) for 3 doses against Omicron. Among hospitalized unvaccinated COVID-19 patients, severity on the WHO Clinical Progression Scale was higher for Delta than Alpha (adjusted proportional odds ratio [aPOR] 1.28, 95% CI: 1.11 to 1.46), and lower for Omicron than Delta (aPOR 0.61, 95% CI: 0.49 to 0.77). Compared to unvaccinated cases, severity was lower for vaccinated cases for each variant, including Alpha (aPOR 0.33, 95% CI: 0.23 to 0.49), Delta (aPOR 0.44, 95% CI: 0.37 to 0.51), and Omicron (aPOR 0.61, 95% CI: 0.44 to 0.85). ConclusionsmRNA vaccines were highly effective in preventing COVID-19-associated hospitalizations from 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 Delta and Alpha. Among adults hospitalized with COVID-19, Omicron caused less severe disease than Delta, but still resulted in substantial morbidity and mortality. Vaccinated patients hospitalized with COVID-19 had significantly lower disease severity than unvaccinated patients for all the variants.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21261849

RESUMO

In comparison to the general patient population, trauma patients show higher level detections of bloodborne infectious diseases, such as Hepatitis and Human Immunodeficiency Virus. In comparison to bloodborne pathogens, the prevalence of respiratory infections such as SARS-CoV-2 and how that relates with other variables, such as drug usage and trauma type, is currently unknown in trauma populations. Here, we evaluated SARS-CoV-2 seropositivity and antibody isotype profile in 2,542 trauma patients from six Level-1 trauma centers between April and October of 2020 during the first wave of the COVID-19 pandemic. We found that the seroprevalence in trauma victims 18-44 years old (9.79%, 95% confidence interval/CI: 8.33 11.47) was much higher in comparison to older patients (45-69 years old: 6.03%, 4.59-5.88; 70+ years old: 4.33%, 2.54 - 7.20). Black/African American (9.54%, 7.77 - 11.65) and Hispanic/Latino patients (14.95%, 11.80 - 18.75) also had higher seroprevalence in comparison, respectively, to White (5.72%, 4.62 7.05) and Non-Latino patients (6.55%, 5.57 - 7.69). More than half (55.54%) of those tested for drug toxicology had at least one drug present in their system. Those that tested positive for narcotics or sedatives had a significant negative correlation with seropositivity, while those on anti-depressants trended positive. These findings represent an important consideration for both the patients and first responders that treat trauma patients facing potential risk of respiratory infectious diseases like SARS-CoV-2.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21259776

RESUMO

BackgroundAs SARS-CoV-2 vaccination coverage increases in the United States (US), there is a need to understand the real-world effectiveness against severe Covid-19 and among people at increased risk for poor outcomes. MethodsIn 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 an mRNA vaccine (Pfizer-BioNTech or Moderna) between cases hospitalized with Covid-19 and hospital-based controls who tested negative for SARS-CoV-2. ResultsAmong 1210 participants, median age was 58 years, 22.8% were Black, 13.8% were Hispanic, and 20.6% had immunosuppression. SARS-CoV-2 lineage B.1.1.7 was most common variant (59.7% of sequenced viruses). Full vaccination (receipt of two vaccine doses [≥]14 days before illness onset) had been received by 45/590 (7.6%) cases and 215/620 (34.7%) controls. Overall vaccine effectiveness was 86.9% (95% CI: 80.4 to 91.2%). Vaccine effectiveness was similar for Pfizer-BioNTech and Moderna vaccines, and highest in adults aged 18-49 years (97.3%; 95% CI: 78.9 to 99.7%). 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 (59.2%; 95% CI: 11.9 to 81.1%) than without immunosuppression (91.3%; 95% CI: 85.5 to 94.7%). ConclusionDuring 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.

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21253178

RESUMO

ObjectiveOur objective was to assess the level of COVID-19 preparedness of emergency departments (EDs) in Aotearoa New Zealand (NZ) through the views of emergency medicine specialists working in district health boards around the country. Given the limited experience NZ hospitals have had with SARS-CoV-2, a comparison of current local practice with recent literature from other countries identifying known weaknesses may help prevent future healthcare worker infections in NZ. MethodsWe conducted a cross-sectional survey of NZ emergency specialists in November 2020 to evaluate preparedness of engineering, administrative policy, and personal protective equipment (PPE) use. ResultsA total of 137 surveys were completed (32% response rate). More than 10% of emergency specialists surveyed reported no access to negative pressure rooms. N95 fit testing had not been performed in 15 (12%) of respondents. Most specialists (77%) work in EDs that cohort COVID-19 patients, about one-third (34%) do not use spotters during PPE doffing, and most (87%) do not have required space for physical distancing in non-patient areas. Initial PPE training, simulations and segregating patients were widespread but appear to be waning with persistent low SARS-CoV-2 prevalence. PPE shortages were not identified in NZ EDs, yet 13% of consultants do not plan to use respirators during aerosol generating procedures on COVID-19 patients. Available treatments including non-invasive ventilation and high-flow nasal cannula were common. ConclusionsNew Zealand emergency specialists identified significant gaps in COVID-19 preparedness, and they have a unique opportunity to translate lessons from other locations into local action. These data provide insight into weaknesses in hospital engineering, policy, and PPE practice in advance of future SARS-CoV-2 endemic transmission. Strengths and limitations of this studyO_LISurvey responses specifically identified existing breakdowns in engineering, administrative policy and personal protective equipment in New Zealand emergency departments, potentially increasing healthcare worker nosocomial infection risk upon reintroduction of SARS-CoV-2 C_LIO_LISurvey included emergency specialists from all 20 of New Zealands district health boards but the electronic convenience sample may not be representative of all ED consultants in NZ C_LIO_LISome survey questions asked respondents to recall experiences or project how they would practice if they were caring for a COVID-19 patient and those motivated to respond may feel they have more or less access to protective policies and equipment than non-respondents C_LI

8.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21250718

RESUMO

BackgroundThroughout 2020, the coronavirus disease 2019 (COVID-19) has become a threat to public health on national and global level. There has been an immediate need for research to understand the clinical signs and symptoms of COVID-19 that can help predict deterioration including mechanical ventilation, organ support, and death. Studies thus far have addressed the epidemiology of the disease, common presentations, and susceptibility to acquisition and transmission of the virus; however, an accurate prognostic model for severe manifestations of COVID-19 is still needed because of the limited healthcare resources available. ObjectiveThis systematic review aims to evaluate published reports of prediction models for severe illnesses caused COVID-19. MethodsSearches were developed by the primary author and a medical librarian using an iterative process of gathering and evaluating terms. Comprehensive strategies, including both index and keyword methods, were devised for PubMed and EMBASE. The data of confirmed COVID-19 patients from randomized control studies, cohort studies, and case-control studies published between January 2020 and July 2020 were retrieved. Studies were independently assessed for risk of bias and applicability using the Prediction Model Risk Of Bias Assessment Tool (PROBAST). We collected study type, setting, sample size, type of validation, and outcome including intubation, ventilation, any other type of organ support, or death. The combination of the prediction model, scoring system, performance of predictive models, and geographic locations were summarized. ResultsA primary review found 292 articles relevant based on title and abstract. After further review, 246 were excluded based on the defined inclusion and exclusion criteria. Forty-six articles were included in the qualitative analysis. Inter observer agreement on inclusion was 0.86 (95% confidence interval: 0.79 - 0.93). When the PROBAST tool was applied, 44 of the 46 articles were identified to have high or unclear risk of bias, or high or unclear concern for applicability. Two studied reported prediction models, 4C Mortality Score from hospital data and QCOVID from general public data from UK, and were rated as low risk of bias and low concerns for applicability. ConclusionSeveral prognostic models are reported in the literature, but many of them had concerning risks of biases and applicability. For most of the studies, caution is needed before use, as many of them will require external validation before dissemination. However, two articles were found to have low risk of bias and low applicability can be useful tools.

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