Disease Severity in COVID-19 Breakthrough Cases

Background Vaccine breakthrough is a phenomenon wherein vaccinated individuals become infected with disease despite adequate protection. During this study period, the Centers for Disease Control (CDC) reported 66.6% of US people have been fully vaccinated. Any measures to improve trust would increase vaccination rates. This study aims to understand vaccine breakthrough cases in COVID-19 by comparing their severity to unvaccinated cases. Our objective is to compare disease severity based on the worst initial vital signs (temperature, respiratory rate, oxygen saturation), length of stay (LOS), and age between vaccinated and unvaccinated COVID-19 cases. Methods We conducted a retrospective cohort study at Berkshire Medical Center between July 15, 2021, through October 31, 2021. IRB exemption was obtained. Patient records were reviewed for vaccination status, age, vital signs, and LOS. We used forward and backward logistic regressions to determine significant variables and odds ratios to quantify the association between them. We then computed two-sample t-tests to compare the variables between vaccinated and unvaccinated groups. Results There were 151 vaccinated and 141 unvaccinated COVID-19 cases. Using a forward logistic regression model, we found significant associations between vaccination status, age (p\u3c0.005), and max Temp (p\u3c0.005). Using a backward logistic regression model, we found significant associations between vaccination status, age (p\u3c0.005), max Temp (p\u3c0.005), and min SpO2 (p\u3c0.031). Odds ratios were 1.0725 (age), 0.6608 (max Temp), and 1.0873 (min SpO2). Two-sample t-tests showed significant differences in age and max Temp between vaccinated and unvaccinated groups while no significant differences were found in LOS, max RR, and min SpO2. Discussion Our results suggest that vaccination may lead to milder disease even against virulent strains such as the Delta variant. These findings were similar to another study during the Alpha variant peak that demonstrated that vaccinated patients had less disease severity. Vaccination was associated with a 7.25% higher likelihood of being older, a 66.08% lower likelihood of having a higher temperature, and an 8.73% higher likelihood of having lower SpO2. There were significant differences in age and max Temp between vaccinated and unvaccinated groups indicating that vaccination may be associated with less disease severity even in an older population

Hemoglobin As A Predictor For COVID-19 Disease Severity

Background: The dilemma of who is at highest risk for COVID-19 severe disease and death persists. Hemoglobin levels may be an indicator of COVID-19 disease severity. There is inconsistent data on Emergency Department (ED) hemoglobin levels and severity of disease. Our objective was to examine if COVID-19 patients presenting with abnormal hemoglobin levels have an increased risk of severe disease and in-hospital mortality. Methods: We conducted a retrospective cohort study at Berkshire Medical Center in Pittsfield, MA to investigate the relationship of COVID-19 disease severity with hemoglobin level. Inclusion criteria consisted of ED patients over 18 years with a COVID-19 diagnosis from July 1, 2021, to November 1, 2021. Exclusion criteria consisted of duplicate visits and patients without a hemoglobin value recorded. Patients with anemia were stratified by severity. Disposition categories from most to least severe were: ICU/PCU, medical floor, or discharge from ED. In-hospital mortality was recorded. Backward linear regression followed by z-tests were used for each abnormal hemoglobin category versus normal hemoglobin category. Results: The four-month period included 341 ED visits coded for COVID-19. After excluding 113 visits, 228 were eligible for analysis. There were 132 discharged from the ED, 64 admitted to the medical floor, 32 to ICU/PCU, and 19 deaths. Backwards linear regression showed hemoglobin category was a significant predictor of hospital disposition (p \u3c 0.0001) and mortality (p = 0.07). Z-test showed a significant difference in disposition for normal hemoglobin versus mild anemia (z = 2.1927, p = 0.03) and normal hemoglobin versus moderate/severe anemia (z = 3.6225, p = 0 0003). Z-test showed a significant difference in death for normal hemoglobin versus moderate/severe anemia (z = 3.2949, p = 0.001). Normal hemoglobin versus elevated hemoglobin had no significant difference for disposition (z = 0.356, p = 0.72) or death (z = 1.786, p = 0.07). Discussion: Abnormal hemoglobin is associated with severity of disease and death COVID-19 patients. Increasingly severe anemia is more associated with severity of disease and death. Elevated hemoglobin is not associated with severity of disease or death