Analysis of an outbreak of COVID-19(alpha-variant) with rapid progression to mortality in Taipei, Taiwan

Risk factors for disease progression and clinical outcomes in patients with COVID-19 in Taiwan: a nationwide population-based cohort study

BACKGROUND

Since 2021, COVID-19 has had a substantial impact on global health and continues to contribute to serious health outcomes. In Taiwan, most research has focused on hospitalized patients or mortality cases, leaving important gaps in understanding the broader effects of the disease and identifying individuals at high risk. This study aims to investigate the risk factors for disease progression through a nationwide population-based cohort study on COVID-19 in Taiwan.

METHODS

This study included 15,056 patients diagnosed with COVID-19 between January 1, 2021, and December 31, 2021, using the Taiwan National Health Insurance Research Database. Baseline and clinical characteristics were collected to verify the association with progression to severity outcomes, including hospital admission, intensive care unit (ICU) admission, invasive ventilatory support, fatal outcome, and the composite outcome of these four events. Patients were observed for 30 days for disease progression. Multivariable logistic regression models were used to calculate odd ratios and 95% confidence intervals (CIs) for each outcome, adjusting for age, sex, region, risk factors, and vaccination status.

RESULTS

Overall, 8,169 patients diagnosed during outpatient visits and 6,887 patients diagnosed during hospitalization were analyzed. Adjusting for age, sex, region, risk factors, and vaccination status, elderly patients had higher risks of hospital admission, ICU admission, invasive ventilatory support, fatal outcome, and composite outcome. Specifically, the risk of the fatal outcome was significantly higher for patients aged 75-84 (odds ratio: 6.11, 95% CI: 4.75-7.87) and those aged 85 years and older (12.70, 9.48-17.02). Patients with cardiovascular disease exhibited higher risks of hospital admission (1.60, 1.31-1.96), ICU admission (1.52, 1.31-1.78), invasive ventilatory support (1.57, 1.26-1.96), and fatal outcomes (1.26, 1.03-1.54) and the composite outcome (1.66, 1.20-1.54). Diabetes mellitus was identified as a significant risk factor for all clinical outcomes (hospital admission: 1.89, 1.53-2.35; ICU admission: 1.53, 1.30-1.79; invasive ventilatory support: 1.27, 1.01-1.60; the composite outcome: 1.45, 1.28-1.66), except for the fatal outcome.

CONCLUSIONS

This study indicated the impact of sex, age, and risk factors on the clinical outcomes of COVID-19 patients in Taiwan. Elderly patients and those with cardiovascular disease or diabetes mellitus had higher risks for severe outcomes, including hospitalization, ICU admission, invasive ventilatory support, and mortality. These findings can provide evidence for a better understanding of risk factors for disease progression and inform targeted intervention.

The Mediating Role of Human Mobility in Temporal-Lagged Relationships Between Risk Perception and COVID-19 Dynamics in Taiwan: Statistical Modeling for Comparing the Pre-Omicron and Omicron Eras

Background

The COVID-19 pandemic has profoundly impacted all aspects of human life for over 3 years. Understanding the evolution of public risk perception during these periods is crucial. Few studies explore the mechanisms for reducing disease transmission due to risk perception. Thus, we hypothesize that changes in human mobility play a mediating role between risk perception and the progression of the pandemic.

Objective

The study aims to explore how various forms of human mobility, including essential, nonessential, and job-related behaviors, mediate the temporal relationships between risk perception and pandemic dynamics.

Methods

We used distributed-lag linear structural equation models to compare the mediating impact of human mobility across different virus variant periods. These models examined the temporal dynamics and time-lagged effects among risk perception, changes in mobility, and virus transmission in Taiwan, focusing on two distinct periods: (1) April-August 2021 (pre-Omicron era) and (2) February-September 2022 (Omicron era).

Results

In the pre-Omicron era, our findings showed that an increase in public risk perception correlated with significant reductions in COVID-19 cases across various types of mobility within specific time frames. Specifically, we observed a decrease of 5.59 (95% CI -4.35 to -6.83) COVID-19 cases per million individuals after 7 weeks in nonessential mobility, while essential mobility demonstrated a reduction of 10.73 (95% CI -9.6030 to -11.8615) cases after 8 weeks. Additionally, job-related mobility resulted in a decrease of 3.96 (95% CI -3.5039 to -4.4254) cases after 11 weeks. However, during the Omicron era, these effects notably diminished. A reduction of 0.85 (95% CI -1.0046 to -0.6953) cases through nonessential mobility after 10 weeks and a decrease of 0.69 (95% CI -0.7827 to -0.6054) cases through essential mobility after 12 weeks were observed.

Conclusions

This study confirms that changes in mobility serve as a mediating factor between heightened risk perception and pandemic mitigation in both pre-Omicron and Omicron periods. This suggests that elevating risk perception is notably effective in impeding virus progression, especially when vaccines are unavailable or their coverage remains limited. Our findings provide significant value for health authorities in devising policies to address the global threats posed by emerging infectious diseases.

COVID-19 outbreaks in long-term care facilities-a nationwide population-based cohort study in Taiwan, May-July 2021

BACKGROUND/PURPOSE

Long-term care facilities (LTCFs) are high-risk settings for the novel coronavirus disease (COVID-19). The aim of the study was to describe the extent and the impacts of 2021 COVID-19 outbreaks on LTCFs in Taiwan.

METHODS

We retrospectively analyzed the data of each COVID-19 outbreak in LTCFs from May 15 to July 31, 2021 in Taiwan. We characterized the features of LTCFs with outbreaks and compared the characteristics of infected staff members and residents of the affected LTCFs.

RESULTS

COVID-19 outbreaks were reported in 16 LTCFs (0.9%). The outbreak was significantly associated with LTCFs with ≥50 beds [adjusted odds ratio (aOR), 6.3; 95%confidence interval [CI], 1.9-21.1] and location of Taipei metropolitan area (aOR, 4.6; 95%CI, 1.7-12.8). Resident cases accounted for 75.4% (203/269) of confirmed cases affected by outbreaks. The 30-day all-cause mortality was 24.2% for residents only and was significantly associated with age ≥65 years [adjusted hazard ratio (aHR, 4.3; 95%CI, 1.7-10.5)], presence of symptoms on diagnosis (aHR, 2.2; 95%CI, 1.3-3.7), and LTCF occupancy rate ≥80% (aHR, 3.0, 95%CI, 1.3-7.4).

CONCLUSION

COVID-19 outbreaks have a critical impact on residents in LTCFs owing to the advanced age and high prevalence of chronic comorbidities in this population. Multi-pronged infection control measures and mass testing are vital for mitigating COVID-19 transmission in LTCFs.

Out-of-hospital cardiac arrest and in-hospital mortality among COVID-19 patients: A population-based retrospective cohort study

BACKGROUND/PURPOSE

Predictors for out-of-hospital cardiac arrest (OHCA) in COVID-19 patients remain unclear. We identified the predictors for OHCA and in-hospital mortality among such patients in community isolation centers.

METHODS

From May 15 to June 20, 2021, this cohort study recruited 2555 laboratory-confirmed COVID-19 patients admitted to isolation centers in Taiwan. All patients were followed up until death, discharge from the isolation center or hospital, or July 16, 2021. OHCA was defined as cardiac arrest confirmed by the absence of circulation signs and occurring outside the hospital. Multinomial logistic regressions were used to determine factors associated with OHCA and in-hospital mortality.

RESULTS

Of the 37 deceased patients, 7 (18.9%) had OHCA and 30 (81.1%) showed in-hospital mortality. The mean (SD) time to OHCA was 6.6 (3.3) days from the symptom onset. After adjusting for demographics and comorbidities, independent predictors for OHCA included age ≥65 years (adjusted odds ratio [AOR]: 13.24, 95% confidence interval [CI]: 1.85-94.82), fever on admission to the isolation center (AOR: 12.53, 95% CI: 1.68-93.34), and hypoxemia (an oxygen saturation level below 95% on room air) (AOR: 26.54, 95% CI: 3.18-221.73). Predictors for in-hospital mortality included age ≥65 years (AOR: 10.28, 95% CI: 2.95-35.90), fever on admission to the isolation centers (AOR: 7.27, 95% CI: 1.90-27.83), and hypoxemia (AOR: 29.87, 95% CI: 10.17-87.76).

CONCLUSIONS

Time to OHCA occurrence is rapid in COVID-19 patients. Close monitoring of patients' vital signs and disease severity during isolation is important, particularly for those with older age, fever, and hypoxemia.

Risk Factors Associated with Mortality in Hospitalized Patients with COVID-19 during the Omicron Wave in Brazil

Considering the imminence of new SARS-CoV-2 variants and COVID-19 vaccine availability, it is essential to understand the impact of the disease on the most vulnerable groups and those at risk of death from the disease. To this end, the odds ratio (OR) for mortality and hospitalization was calculated for different groups of patients by applying an adjusted logistic regression model based on the following variables of interest: gender, booster vaccination, age group, and comorbidity occurrence. A massive number of data were extracted and compiled from official Brazilian government resources, which include all reported cases of hospitalizations and deaths associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Brazil during the "wave" of the Omicron variant (BA.1 substrain). Males (1.242; 95% CI 1.196-1.290) aged 60-79 (3.348; 95% CI 3.050-3.674) and 80 years or older (5.453; 95% CI 4.966-5.989), and hospitalized patients with comorbidities (1.418; 95% CI 1.355-1.483), were more likely to die. There was a reduction in the risk of death (0.907; 95% CI 0.866-0.951) among patients who had received the third dose of the anti-SARS-CoV-2 vaccine (booster). Additionally, this big data investigation has found statistical evidence that vaccination can support mitigation plans concerning the current scenario of COVID-19 in Brazil since the Omicron variant and its substrains are now prevalent across the entire country.

Rhabdomyolysis in Pediatric Patients with SARS-CoV-2 Infection

Background: Rhabdomyolysis is a rare but severe complication in adult patients with Coronavirus disease 2019 (COVID-19), which can result in acute kidney injury and death; however, it is rarely reported in pediatric patients. Methods: In this study, we retrospectively reviewed the clinical features and outcomes of rhabdomyolysis in pediatric patients aged 0–18 years with COVID-19 who were hospitalized at Taipei Tzu Chi Hospital, an epicenter of COVID-19 in northern Taiwan. Results: We treated eight patients with rhabdomyolysis during the omicron variant-Severe acute respiratory syndrome coronavirus 2 (omicron variant-SARS-CoV-2) community outbreak and none during the alpha variant endemic. These eight patients shared stereotypical presentations, including the presence of bilateral calf pain after defervescence. The creatinine kinase (CK) levels were between 1346 and 6937 U/L on admission, and clinical course was uneventful after aggressive saline hydration. Conclusion: Rhabdomyolysis is not a rare complication in pediatric patients with the omicron-SARS-CoV-2 infection, and reassurance of a good prognosis is important to alleviate family anxiety.

Severity of COVID-19 cases in the months of predominance of the Alpha and Delta variants

New SARS-CoV-2 may pose problems in controlling the COVID-19 pandemic for public health. We aimed to assess and compare the symptoms and severity of cases due to the Alpha and Delta variant dominance periods, taking into account the effect of COVID-19 vaccination. A prospective epidemiological study of SARS-CoV-2 in Lleida was made to determine differences between Alpha and Delta variants periods. We assessed symptoms, specific comorbidities, sociodemographic information and vaccination status. Bivariate and logistic regression analyses were used to estimate the adjusted odds ratio (aOR) and 95% confidence intervals (CI) to investigate the relationship between symptoms and severity and the variants. Alpha variant period compared to the Delta showed an increased risk of ICU admission (aOR 2.0; 95% CI 1.2–2.3) and death (aOR 2.6; 95% CI 1.8–3.9) and cases were associated with people aged > 85 years (aOR 2.1; 95% CI 1.7–2.6) and partially vaccinated (aOR 5.6; 95% CI 3.2–9.9) and unvaccinated people (aOR 27.8; 95% CI 19.7–40.5). Fever, cough and vomiting were significantly associated with the Alpha variant compared to the Delta (aOR 1.6 (95% CI 1.5–1.7), 2.0 (95% CI 1.9–2.2) and 2.5 (95% CI 2.2–2.9, respectively). Our results show that the severity and profile of clinical symptoms varied according to the variant. The risk of ICU admission and death was higher in the Alpha period compared to the Delta as it affected the elderly and cases were less vaccinated.

COMPARISON OF SARS-COV-2 WUHAN AND ALPHA VARIANTS: CLINICAL AND LABORATORY HIGHLIGHTS.. [DOI: 10.1101/2022.05.17.22275188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Since December 2019, after the declaration of new cases regarding novel coronavirus disease, many variants have emerged as a consequence of the viral evolution. Though the SARS-CoV-2 variants have been studied for molecular basis, the clinical and pathologic disparities of them have been understood inadequately. The aim of this research was to figure out the differences between the SARS-CoV-2 Alpha (B1.1.7) variant and the classical Wuhan groups on the clinical basis and laboratory results of the COVID-19 patients who had positive PCR test.The study was done retrospectively inclusive of epidemiological, laboratory data and clinical symptoms of patients who were admitted to the emergency service between February 15 and March 15, 2021 and had positive COVID-19 PCR test results. Though there was no statistically significant difference in symptoms between SARS-CoV-2 Alpha variant and classical variant (Wuhan type) groups; C-reactive protein (CRP), lymphocyte and leukocyte counts were statistically significantly higher in the Wuhan type group; prothrombin time (PT), International Normalized Ratio (INR) and serum creatinine values were statistically significantly higher in the Alpha group. Studies such as ours that investigate both the clinical features and laboratory data of SARS-CoV-2 variants will close the knowledge gaps, so better decisions may be made by health policy makers. Additional studies in this area will increase the understanding of the topic.

Identification and Analysis of SARS-CoV-2 Alpha Variants in the Largest Taiwan COVID-19 Outbreak in 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is believed to have originated in Wuhan City, Hubei Province, China, in December 2019. Infection with this highly dangerous human-infecting coronavirus via inhalation of respiratory droplets from SARS-CoV-2 carriers results in coronavirus disease 2019 (COVID-19), which features clinical symptoms such as fever, dry cough, shortness of breath, and life-threatening pneumonia. Several COVID-19 waves arose in Taiwan from January 2020 to March 2021, with the largest outbreak ever having a high case fatality rate (CFR) (5.95%) between May and June 2021. In this study, we identified five 20I (alpha, V1)/B.1.1.7/GR SARS-CoV-2 (KMUH-3 to 7) lineage viruses from COVID-19 patients in this largest COVID-19 outbreak. Sequence placement analysis using the existing SARS-CoV-2 phylogenetic tree revealed that KMUH-3 originated from Japan and that KMUH-4 to KMUH-7 possibly originated via local transmission. Spike mutations M1237I and D614G were identified in KMUH-4 to KMUH-7 as well as in 43 other alpha/B.1.1.7 sequences of 48 alpha/B.1.1.7 sequences deposited in GISAID derived from clinical samples collected in Taiwan between 20 April and July. However, M1237I mutation was not observed in the other 12 alpha/B.1.1.7 sequences collected between 26 December 2020, and 12 April 2021. We conclude that the largest COVID-19 outbreak in Taiwan between May and June 2021 was initially caused by the alpha/B.1.1.7 variant harboring spike D614G + M1237I mutations, which was introduced to Taiwan by China Airlines cargo crew members. To our knowledge, this is the first documented COVID-19 outbreak caused by alpha/B.1.1.7 variant harboring spike M1237I mutation thus far. The largest COVID-19 outbreak in Taiwan resulted in 13,795 cases and 820 deaths, with a high CFR, at 5.95%, accounting for 80.90% of all cases and 96.47% of all deaths during the first 2 years. The high CFR caused by SARS-CoV-2 alpha variants in Taiwan can be attributable to comorbidities and low herd immunity. We also suggest that timely SARS-CoV-2 isolation and/or sequencing are of importance in real-time epidemiological investigations and in epidemic prevention. The impact of D614G + M1237I mutations in the spike gene on the SARS-CoV-2 virus spreading as well as on high CFR remains to be elucidated.

Healthcare-associated COVID-19 outbreaks: a nationwide population-based cohort study

Background

Aim

Methods

Findings

Conclusion