ABSTRACT
Governments and public health authorities use seroprevalence studies to guide responses to the COVID-19 pandemic. Seroprevalence surveys estimate the proportion of individuals who have detectable SARS-CoV-2 antibodies. However, serologic assays are prone to misclassification error, and non-probability sampling may induce selection bias. In this paper, non-parametric and parametric seroprevalence estimators are considered that address both challenges by leveraging validation data and assuming equal probabilities of sample inclusion within covariate-defined strata. Both estimators are shown to be consistent and asymptotically normal, and consistent variance estimators are derived. Simulation studies are presented comparing the estimators over a range of scenarios. The methods are used to estimate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence in New York City, Belgium, and North Carolina.
ABSTRACT
Background. Development of robust vaccination guidelines against SARS-CoV-2 requires an understanding of the longitudinal antibody (Ab) response to vaccination and interactions with natural infection. Here, we leveraged an observational cohort study of healthcare personnel (HCP) to study the impact of prior SARS-CoV-2 infection on Ab binding and neutralization after mRNA-based vaccination over a 13 month period. Methods. From July 2020 to February 2022, HCP at an academic medical center provided blood samples biweekly for 12 weeks and monthly thereafter. First and second vaccine doses became available in mid-December 2021 and boosters were available starting in October 2021. Individuals were excluded if they did not provide any samples, if baseline serostatus was unknown, and if they received a monoclonal Ab treatment for COVID. ELISA measured total immunoglobulin (Ig) and IgG binding to SARS-CoV-2 RBD. Neutralization was measured by live virus Nanoluc SARS-CoV-2ic assay. Demographics, serostatus, and vaccinations for the total study population and the sub-sample of participants with pre- and post-vaccination antibody measurements. Results. Of 213 participants, 192 met inclusion criteria. A majority had detectable IgG levels 8 months after a second dose. Prior to vaccination, median total Ig was higher among seropositive vs. seronegative participants (3.7 vs 1.0, p< 0.001). After a first dose, the median total Ig response was two-fold higher in seropositive compared to seronegative participants (13.8 vs. 7.0, p=0.009). A similar pattern was noted with IgG binding and neutralization. After the second dose, median IgG increased to similar levels in both seropositive and seronegative participants (22.1 vs. 21.2, p=0.8). Neutralization after the second dose was slightly higher in seropositive vs. seronegative participants (log10 3.1 vs. 2.5, p=0.075). Durability of IgG responses after second dose of mRNA-based vaccination against SARS-CoV-2 IgG P/N measurements after 5 days post-V2 for the entire study cohort (incident seropositive: yellow circles, prevalent seropositive (red circles), seronegative (open circles) are shown. The solid lines represent Loess curves for incident and prevalent seropositive participants combined (orange line) and those who were seronegative (grey line). SARS-CoV-2-specific total Ig and IgG subtype responses among healthcare personnel before and after vaccination against SARS-CoV-2 with an mRNA-based vaccine. Total Ig P/N ratios at pre-vaccine, post-V1, post-vaccine 2 (post-V2), and post-booster dose (post-boost) timepoints by serostatus (seronegative: n(-), seropositive: n(+)) are shown in the left panel. For the pre-vaccine time point, the most recent antibody level prior to vaccination (for those who were vaccinated) or most recent antibody level overall (for those who were not vaccinated) is shown. For the post-vaccine time points, the first measurement after 5 days post-vaccination is included. Individuals who were infected with SARS-CoV-2 at any time after the first vaccine dose are shown as open circles with black outlines. The black numbers next to the circles indicate the number of days between vaccination and sample collection for seropositive individuals. SARS-CoV-2 specific IgG P/N ratios respectively at pre-vaccine, post-V1, post-V2, and post-boost timepoints by serostatus (seronegative: n(-), seropositive: n(+)) are shown in the right panel. One individual tested positive for SARS-CoV-2 by PCR shortly after the second vaccine dose (V2);post-V2 results were excluded for this participant. For the pre-vaccine time point, the most recent antibody level prior to vaccination (for those who were vaccinated) or most recent antibody level overall (for those who were not vaccinated) is shown. For the post-vaccine time points, the first measurement after 5 days post-vaccination is included. The dotted line is a P/N ratio of 2.4, the cut-off associated with 99.3% specificity (SARS-CoV-2 IgG-positive above the line, IgG-negative below). Individuals who were infected with SARS-CoV-2 at any t me after the first vaccine dose are shown as open circles with black outlines. The black numbers next to the circles indicate the number of days between vaccination and sample collection for seropositive individuals. SARS-CoV-2 D614G live virus neutralization among healthcare personnel by serostatus prior to vaccination. Example neutralization curves are shown in Panel A. Panel B shows the SARS-CoV-2 D614G live virus neutralization titers displayed as EC50 for seropositive (prevalent and incident) individuals and a subset of seronegative individuals. Samples for seronegative individuals were selected by matching on age and time between vaccination and sample collection to the samples from seropositive individuals. Conclusion. Antibody responses after SARS-CoV-2 vaccination persist up to 1 year with wide individual variability. Though prior infection was associated with greater Ab responses after a first dose, it did not significantly modify responses after second and third doses. Still, we observed overall slightly higher Ab levels among individuals that had a prior infection before any one of the 3 doses of vaccine. These results suggest that immunity against SARS-CoV-2 prior to vaccination has a role in initial response but does not significantly modify circulating Ab titers after multiple doses of vaccination.
ABSTRACT
Objective: To summarize pharmacy students' previous experience and current confidence with online learning and explore the association of prior experience with online learning and resilient coping with perceived stress at the beginning of the COVID-19 pandemic. Method(s): Students completed an online cross-sectional survey during April-June, 2020. Measures included Likert items for experience and current comfort levels with online learning;the Brief Resilient Coping Scale (BRCS);and the Perceived Stress Scale-10 Item Version (PSS-10). We summarized experience and comfort with online learning;reported scores and internal consistency for the BRCS and PSS-10;and estimated a regression model of perceived stress as a function of prior experience with online education, gender, and resilient coping. Result(s): Of 113 respondents (response rate 41%, 78% female, mean age 22.3 years) >50% had only occasional prior experience with online learning, coursework, and examinations, but 63% expressed confidence with online learning. Mean PSS-10 and BRCS scores were 23.8 and 13.3 respectively, and both scales demonstrated good internal consistency (a > .80). BRCS score was the single predictor of PSS-10 score (r2 = 0.18, p < 0.001). Gender was not a significant predictor of perceived stress (p = 0.11). A simultaneous regression model explained a moderate amount of variation in perceived stress (adjusted R2 = 0.19). Conclusion(s): Most students had limited previous online learning, coursework, and examination experience. Responses indicated moderate levels of stress and coping skills after introducing online teaching. Lower resiliency scores, but not lack of virtual learning experience, predicted higher perceived stress. Results underscore the importance of efforts to enhance coping and resilience of students.
ABSTRACT
The impact of coronavirus disease 2019 (COVID-19) pandemic has raised health concerns worldwide. Medical and allied health professional schools are seeking ways to alleviate stress and improve the quality of life among students. The effects of yoga have proven to be successful against stress. The review aimed to examine the psychophysiological effects of yoga on stress management among medical and allied health professional students during COVID-19 pandemic. The authors reviewed existing literature and official documents, which mostly focussed on the effect of yoga among medical and health professional students. Mental stress among these students is known to be higher than that of the general population. Sudden changes due to the pandemic are likely to have a significant impact on these students. Uncertainties concerning teaching, learning and assessment generate stress and anxiety, and social distancing further contributes to loneliness. Yoga has gained recognition not only in improving mental health and quality of life, but it also helps in improving respiratory and immune health. Although many published studies examined the psychophysiological effects of yoga among health professional students;only a few medical and allied health professional schools have incorporated yoga into an integrated curriculum for a holistic approach. In response to the COVID-19 crisis, the use of yoga for stress reduction and immune modulation should be considered as a complement to other treatments. There is a need to integrate yoga into medical and health science curricula to prepare physically fit and mentally sound prospective healthcare professionals.
ABSTRACT
The emergence and global spread of COVID-19 has disrupted the traditional mechanisms of education throughout the world. Institutions of learning were caught unprepared and this jeopardised the face-to-face method of curriculum delivery and assessment. Teaching institutions have shifted to an asynchronous mode whilst attempting to preserve the principles of integrity, equity, inclusiveness, fairness, ethics, and safety. A framework of assessment that enables educators to utilise appropriate methods in measuring a student's progress is crucial for the success of teaching and learning, especially in health education that demands high standards and comprises consistent scientific content. Within such a framework, this paper aims to present a narrative review of the currently utilised methods of assessment in health education and recommend selected modalities that could be administered in an asynchronous mode during the COVID-19 pandemic. Assessment methods such as open-ended short answer questions, problem-based questions, oral exams, and recorded objective structured clinical exams (OSCE) would be appropriate for use in an asynchronous environment to assess the knowledge and competence of health professional students during COVID-19. Fairness and integrity can be ensured by using technological tools such as video and audio recording surveillance.