ABSTRACT
Background: Immunocompromised patients with COVID-19 tend to shed viable virus for a prolonged period. Therefore, for moderately or severely immunocompromised patients with COVID-19, CDC recommends an isolation period of at least 20 days and ending isolation in conjunction with serial testing and consultation with an infectious disease specialist. However, data on viral kinetics and risk factors for prolonged viral shedding in these patients are limited. Method(s): From February 1, 2022 to April 1, 2022, we collected weekly saliva samples from immunocompromised patients with COVID-19 admitted to a tertiary hospital in Seoul, South Korea. Genomic and subgenomic RNAs were measured, and virus culture was performed. Result(s): A total of 41 patients were enrolled;29 (70%) were receiving chemotherapy against hematologic malignancies and the remaining 12 (30%) had undergone solid organ transplantation. Of the 41 patients, 14 (34%) had received 3 doses or more of COVID-19 vaccines. Real-time RT-PCR revealed that 7 (17%) were infected with Omicron BA.1, and 33 (80%) with Omicron BA.2. The median duration of viable virus shedding was 4 weeks (IQR 3-6). Patients undergoing B-cell depleting therapy shed viable virus for longer than the comparator (p=0.01). Multivariable analysis showed that 3-dose or more vaccination (HR 0.33, 95% CI 0.12 - 0.93, p = 0.04) and B-cell depleting therapy (HR 12.50, 95% CI 2.44 - 100.00, p = 0.003) independently affected viable virus shedding of SARS-CoV-2. Conclusion(s): Immunocompromised patients with COVID-19 shed viable virus for median 4 weeks. B-cell depleting therapy increases the risk of prolonged viable viral shedding, while completion of a primary vaccine series reduces this risk. Overall distribution of samples according to genomic viral copy number and culture positivity. Red dot indicates positive culture results, whereas blue dot indicated negative culture results. (Figure Presented).
ABSTRACT
Introduction: Like most educational institutions, our medical school transitioned to online learning during the COVID-19 pandemic in March 2020. An initial survey of 192 undergraduate medical students conducted in June 2020 revealed a low acceptance of online assessments, lack of work-readiness, perception of online discussions as being inferior to face-to-face, and prevalent anxiety. Following this, we implemented pedagogic changes to encourage independent learning, improve patient contact, and increase social interactions between students. Methods: A follow-up study was conducted 12 months later in the same student population, excluding those who had graduated. The same 14-item anonymized survey questionnaire was administered, and comparisons were made between the follow-up and initial responses. Results: At follow-up, 45.6% of participants felt that online assessments can adequately and fairly assess students' performance compared to the initial study (26.2%, p = 0.002). Participants at follow-up were generally more agreeable that discussion using an online learning platform was as effective as face-to-face learning compared to before (p = 0.017). Subgroup analysis showed that this was only true for Year 2 - 4 students. Year 5 students perceived online learning as less effective then face-to-face, reported lower confidence in their ability to apply their knowledge, and an increased in anxiety compared to before. Conclusion: While perception of online learning and assessment had improved at follow-up, the ramifications from restrictions to medical education over the past two years are now being felt most severely by the current final year students, emphasizing the importance of anticipating and addressing these concerns much earlier. © 2022 UPM Press. All rights reserved.
ABSTRACT
Background: There are limited data on the rates of the waning of antibody levels after two-dose and booster vaccination according to the different platforms of COVID-19 vaccines. Methods: We enrolled healthcare workers (HCWs) in a tertiary care hospital who received homologous two-dose vaccination, followed by a homologous or heterologous booster mRNA vaccine. SARS-CoV-2 S1-specific IgG was measured using ELISA. A linear mixed regression model was used to compare the slope from the peak antibody titer to the lowest antibody titers 3 months after vaccination. Results: A total of 113 HCWs (BNT162b2 (n=48 [42%]), ChAdOx1 nCoV-19 (n=52 [46%]) or mRNA-1273 (n=13 [12%])) were enrolled in this prospective cohort study. More gradual antibody waning was observed over 3 months with the two-dose ChAdOx1 nCoV-19 (ChAdOx1) than with the two-dose BNT162b2 or mRNA-1273 (p< 0.001 and p=0.001, respectively). In addition, homologous mRNA-1273 booster induced a more durable antibody response than homologous BNT162b2 booster (p< 0.001) or heterologous ChAdOx1-BNT162b2 booster (p< 0.001). Conclusion: 2-dose homologous ChAdOx1 vaccination or homologous mRNA-1273 booster appears to induce more-durable antibody responses than 2-dose homologous mRNA vaccination, homologous BNT162b2 booster, or 2-dose ChAdOx1 followed by BNT162b2 booster. Disclosures: All Authors: No reported disclosures.
ABSTRACT
Background. There are few data on immune correlation of protection from breakthrough Omicron (B.1.1.529) infection in individuals who received booster vaccines. We thus compared a neutralizing antibody titers against Omicron within the first month after the mRNA booster at the time before omicron wave between healthcare works (HCWs) who experienced Omicron breakthrough infections and HCWs without Omicron infections. Methods. We enrolled HCWs without the history of SARS-CoV-2 infection who agreed with blood sampling 2 weeks after booster vaccination at Asan Medical Center, Seoul, South Korea, between November 2021 and December 2022 (Delta dominant era). We identified breakthrough infections by performing SARS-CoV-2 RT-PCR though nasopharyngeal swab specimen in HCWs who had COVID-19-related symptoms or had known exposure to confirmed SARS-CoV-2-infected patients, between 1 February and 25 April 2022 (Omicron dominant era). SARS-CoV-2 S1-specific IgG antibody titers were measured using enzyme-linked immunosorbent assay (ELISA). Plasma levels of live-virus neutralizing antibodies were measured using a microneutralization assay with SARS-CoV-2 omicron variants. Results. Among 134 HCWs, 69 (52%) received two-dose ChAdOx1 nCoV-19 followed by BNT162b2, 50 (37%) three-dose BNT162b2, and 15 (11%) 3-dose mRNA-1273. Of them, 57 (43%) experienced breakthrough Omicron infection at median 121 days (IQR 99-147) after booster vaccination (breakthrough group), and the remaining 77 (57%) did not experience Omicron infection (non-breakthrough group). There was no significant different in 'peak' SARS-CoV-2 S1-specific IgG level between breakthrough group (median 4484.4 IU/mL) and non-breakthrough group (median 4194.9 IU/mL, p value=0.39). In addition, there was no significant difference in 'peak' neutralizing antibody titer (ID50) against Omicron between breakthrough group (median 2597.9) and non-breakthrough group (median 2597.9, p value=0.86). (Table Presented) Serum samples were obtained from 134 healthcare workers 2 weeks after booster vaccination. Samples were analysed for SARS-CoV-2 S1-specific IgG antibody titers using enzyme-linked immunosorbent assay (ELISA) and plasma levels of live-virus neutralizing antibodies using a microneutralization assay with SARS-CoV-2 omicron variants. There was no significant difference in 'peak' SARS-CoV-2 S1-specific IgG level (A) and 'peak' neutralizing antibody titer (ID50) against Omicron (B) between breakthrough group and non-breakthrough group. Conclusion. We did not find the correlation of neutralizing antibody titers about several months before infection with breakthrough Omicron infections. These data suggest rapidlywaning neutralizing titers to protect mild illnesses or asymptomaticOmicron infections several months after current booster COVID-19 vaccination in HCWs.
ABSTRACT
Background. Centers for Disease Control and Prevention (CDC) recommends 5 to 20 days of isolation for COVID-19 patients depending on symptom duration and severity regardless of genomic PCR results or vaccination history. However, in real clinical practice, more individualized approach is required. We thus developed clinical scoring system to predict viable viral shedding in a given patient by using various factors affecting viable viral shedding. Methods. We prospectively enrolled adult patients with SARS-CoV-2 infection admitted to tertiary hospital and day care center between February 2020 and January 2022. The daily dense respiratory sampling (i.e. saliva, sputum, or nasopharyngeal swabs) during the hospital and day care center stay were obtained. Genomic RNA viral load and viral culture were performed for these samples. Clinical predictors of negative viral culture results were identified using survival analysis and multivariable analysis. Results. A total of 612 samples from 121 patients of varying degrees of severity were obtained. Of these, 494 (81%) samples were saliva, 63 (10%) were nasopharyngeal swab, and the remaining 55 (9%) were sputum. Of these 612 specimens, 154 (25%) samples revealed positive viral culture results. Univariate and multivariable Cox's time varying proportional hazard model revealed that symptom onset day, viral copy number, disease severity, organ transplant recipient, gender, and vaccination status were independently associated with viral culture results. We thus developed the 5-factor model from -3 to 3 points: viral copy number (-3 to 3 points depending on copy number), disease severity (1 point to moderate to critical diseases), organ transplant recipient (2 points), gender (-1 points to male), and vaccination status (-2 points to fully vaccinated status). The predictive culture-negative rates were calculated through the symptom onset day and the score of the day the sample was collected. Conclusion. Our clinical scoring system can provide objective probability of negative culture results in a given COVID-19 patient with genomic viral load, and appears to be useful to decide de-isolation policy depending on individualized factors associated with viable viral shedding beyond simple symptom-based isolation strategy by CDC.
ABSTRACT
Background. Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) variant strain B.1.1.529 (omicron) has been less virulent than SARS-CoV-2 B.1.617.2 variant (delta), but there are limited data on the comparison of the cause of death between delta variant and omicron variant infections. We thus compared the causes of death in COVID-19 patients with the delta variant and omicron variant. Methods. We retrospectively reviewed the medical records of adult patients with COVID-19 who were admitted at Asan Medical Center, Seoul, South Korea, between July 2021 and March 2022. We divided into delta-variant dominant period (from July 2021 to December 2021) and omicron-dominant period (from February 2022 to March 2022) with the exclusion of January 2022 because this period was overlapping of delta and omicron variant. The causes of death were classified into COVID-19-associated pneumonia, other causes, and indeterminate cause. Results. A total of 654 patients with COVID-19 were admitted and 42 (6.4%) died during the omicron dominant period (between February and March 2022), while a total of 366 patients with COVID-19 were hospitalized and 42 (11.5%) died during the delta dominant period (between July and December 2021). The primary cause of death was COVID-19-associated pneumonia in 64% (27/42) during the omicron era whereas that was COVID-19-associated pneumonia in 88% (37/42) during the delta era (p value=0.01) (Table 1). Conclusion. We found that about two thirds of patients with omicron variant infection died due to COVID-19, while the majority of patients with delta variant infection died due to COVID-19.
ABSTRACT
The campus closure and lockdown due to the COVID-19 pandemic which took place in 2020 had resulted in the adoption of virtual learning in higher learning institutions in Malaysia. The implementation of fully online learning approaches required both learners and educators to adapt to online assessment methods. In line with this, the shift from physical and written tests to online tests had a significant impact on teaching and learning in the virtual classroom. This paper presents students' preferences for online assessment platforms and types of assessment questions. This study also explores the impact of online assessment towards students' performance during virtual learning. Data was collected through an online questionnaire distributed to students from Multimedia University (MMU), Malaysia. This study found that students preferred closed-ended questions design and Google Classroom as the platform of online assessment. This study also revealed that students' academic performance improved during online learning. The findings of this study will be useful to academics and educators in designing effective online assessments if online learning continues after the pandemic. It also provides a framework for future research into the perceptions of online assessment among educators and academics. © 2022 IEEE.
ABSTRACT
Purpose: The effects of the COVID-19 pandemic have been devastating to countries around the world. Much of the problem has been the need to contain the infection via harsh social movement restrictions while having the necessary policies to cushion the ensuing economic blows that follow them. This study aims to look at The Association of Southeast Asian Nations (ASEAN) countries and assess the good practices that are associated with those which performed relatively better than the rest. Design/methodology/approach: The authors use data envelopment analysis (DEA) to identify the most efficient country among the ASEAN nations in dealing with the pandemic and observe their practices with regard to the movement control metrics. Findings: One particular country stood out in this regard, which is Singapore. The authors observed that its social restrictions were less stringent than many others yet its management of the pandemic has been highly successful despite having had the highest number of cases at one stage in 2020. This suggests massive lockdowns may not necessarily be the solution. However, the nation did place a high priority in having a high-income support, effective public campaigning and very restrictive policy on public events. In terms of originality and value, this paper uses DEA in identifying the best practice among ASEAN countries in dealing with the pandemic, both from an economic and medical perspectives. Originality/value: To the best of the authors’ knowledge, no other papers have used this approach. The authors hope the findings can be of some value to policymakers in designing better (public) policies when it comes to dealing with pandemics in the future. © 2022, Emerald Publishing Limited.
ABSTRACT
Background. In early months of COVID-19 pandemic, SGH recorded a year-on-year increase in antibiotic (ABx) use for community acquired acute respiratory infection (CA ARI) from Feb-Apr 2019 (48.7 defined daily doses (DDD)/100 bed-days) to 2020 (50.8 DDD/100 bed-days). To address concerns of misuse, the antibiotic stewardship unit (ASU) expanded prospective audit feedback (PAF) to CA ARI patients admitted to ARI wards, with low procalcitonin (PCT). PAF was conducted on day 2-3 of ABx, on weekdays. Doctors received feedback to stop/ modify when ABx was deemed inappropriate. Here, we describe the impact of ASU's adaptive approach to curb rising ABx use in patients admitted for ARI during COVID-19 pandemic. Methods. A Pre- & Post-intervention study was conducted. All patients started on ABx (ceftriaxone/co-amoxiclav/piptazo/carbapenems/levofloxacin) for CA ARI & PCT < 0.5μg/L were analysed. Those who died ≤48h of admission;admitted to intensive care;required ABx escalation;>1 infective sites;complex lung infection were excluded. Primary objective was to compare the proportion of ABx stopped ≤4 days (time to final infection diagnosis) Pre (22/3-18/4/20) & Post (21/4-13/7/20). Results. 184 (Pre) & 528 (Post) ABx courses were analysed. ASU audited 51 (Pre) & 380 (Post) courses with the rest discontinued/discharged before review. Patients were largely similar in both periods;a third had low likelihood of bacterial infection (C reactive protein < 30mg/L). In Post, 73 feedback was given to stop ABx (often because symptoms suggested viral/fluid overload) & 18 to switch to oral ABx. 82 (90%) feedback was accepted. No ABx was restarted ≤48h or deaths ≤30 days due to ARI. 1 patient had C. difficile diarrhoea a day after ABx cessation as per ASU feedback. Proportion of all ABx stopped ≤4 days was higher in Post than Pre [27/184 (15%) vs 152/528 (29%), p< 0.01]. Median duration of therapy of IV ABx was reduced (6.5 vs 3 days, p< 0.01), with corresponding shorter median length of stay (10.5 vs 6 days, p< 0.01). Conclusion. PAF directly and indirectly reduced ABx duration in patients treated for CA ARI as prescribers become more conscious about stopping ABx when investigations show low likelihood of bacterial infection. ASU must remain agile during pandemics to detect emerging problems and adapt processes to counter early.
ABSTRACT
BACKGROUND: There is growing evidence that super-spreading events (SSEs) and multiple-spreading events (MSEs) are a characteristic feature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, data regarding the possibility of SSEs or MSEs in healthcare settings are limited. METHODS: This study was performed at a tertiary-care hospital in Korea. We analysed the nosocomial COVID-19 cases that occurred in healthcare workers and inpatients and their caregivers between January and 20th December 2020. Cases with two to four secondary cases were defined as MSEs and those with five or more secondary cases as SSEs. FINDINGS: We identified 21 nosocomial events (single-case events, N = 12 (57%); MSE + SSE, N = 9 (43%)) involving 65 individuals with COVID-19. Of these 65 individuals, 21 (32%) were infectors. The infectors tended to have a longer duration between symptom onset and diagnostic confirmation than did the non-infectors (median two days vs zero days, P=0.08). Importantly, 12 (18%) individuals were responsible for MSEs and one (2%) for an SSE, which collectively generated 35 (54%) secondary cases. CONCLUSION: In a hospital with thorough infection-control measures, approximately 70% of the nosocomial cases of COVID-19 did not generate secondary cases, and one-fifth of the infectors were responsible for SSEs and MSEs, which accounted for approximately half of the total cases. Early case identification, isolation, and extensive contact tracing are important for the prevention of transmission and SSEs.