Multilayer factors associated with excess all-cause mortality during the omicron and non-omicron waves of the COVID-19 pandemic: time series analysis in 29 countries.

BACKGROUND: The COVID-19 pandemic has resulted in significant excess mortality globally. However, the differences in excess mortality between the Omicron and non-Omicron waves, as well as the contribution of local epidemiological characteristics, population immunity, and social factors to excess mortality, remain poorly understood. This study aims to solve the above problems. METHODS: Weekly all-cause death data and covariates from 29 countries for the period 2015-2022 were collected and used. The Bayesian Structured Time Series Model predicted expected weekly deaths, stratified by gender and age groups for the period 2020-2022. The quantile-based g-computation approach accounted for the effects of factors on the excess all-cause mortality rate. Sensitivity analyses were conducted using alternative Omicron proportion thresholds. RESULTS: From the first week of 2021 to the 30th week of 2022, the estimated cumulative number of excess deaths due to COVID-19 globally was nearly 1.39 million. The estimated weekly excess all-cause mortality rate in the 29 countries was approximately 2.17 per 100,000 (95% CI: 1.47 to 2.86). Weekly all-cause excess mortality rates were significantly higher in both male and female groups and all age groups during the non-Omicron wave, except for those younger than 15 years (P < 0.001). Sensitivity analysis confirmed the stability of the results. Positive associations with all-cause excess mortality were found for the constituent ratio of non-Omicron in all variants, new cases per million, positive rate, cardiovascular death rate, people fully vaccinated per hundred, extreme poverty, hospital patients per million humans, people vaccinated per hundred, and stringency index. Conversely, other factors demonstrated negative associations with all-cause excess mortality from the first week of 2021 to the 30th week of 2022. CONCLUSION: Our findings indicate that the COVID-19 Omicron wave was associated with lower excess mortality compared to the non-Omicron wave. This study's analysis of the factors influencing excess deaths suggests that effective strategies to mitigate all-cause mortality include improving economic conditions, promoting widespread vaccination, and enhancing overall population health. Implementing these measures could significantly reduce the burden of COVID-19, facilitate coexistence with the virus, and potentially contribute to its elimination.

Hospitalized children with COVID-19 infection during large outbreak of SARS-CoV-2 Omicron strain: a retrospective study in Chaozhou, Guangdong, China.

OBJECTIVE: We aimed to investigate the clinical findings of hospitalized paediatric COVID-19 patients by the end of 2022. METHOD: All confirmed children with COVID-19 infection admitted into Chaozhou Central Hospital during the COVID-19 outbreak from 19 December 2022 to 1 February 2023 were included. Detailed clinical data of those children were evaluated retrospectively. RESULTS: A total of 286 children, ranging in age from 1 month to 13 years old, were diagnosed with SARS-CoV-2 infection. Among these cases, 138 (48.3%) were categorized as mild, 126 (44.0%) as moderate and 22 (7.7%) as severe/critical. Symptoms varied among the children and included fever, upper respiratory tract symptoms, convulsions, sore throat, poor appetite, dyspnoea and gastrointestinal symptoms. Notably, febrile convulsions were observed in 96 (33.6%) patients, while acute laryngitis was documented in 50 (17.5%) cases. Among the severe/critical patients, eight developed multisystem inflammatory syndrome in children (MIS-C), and tragically, one patient's condition worsened and resulted in death. Furthermore, MRI scans revealed abnormal brain signals in six severe/critical patients. The severe/critical group also exhibited more pronounced laboratory abnormalities, including decreased haemoglobin and elevated ALT, AST, LDH and CK levels. CONCLUSIONS: Febrile convulsions and acute laryngitis are frequently observed in children diagnosed with SARS-CoV-2 Omicron infection. Moreover, MIS-C and abnormal neuroimaging appear to be relatively common phenomena in severe/critical cases.

Characteristics of Coronavirus Disease in Allogeneic Hematopoietic Stem Cell Transplantation During the Omicron Wave: A Single-Center Study.

Objectives: This study aimed to characterize the clinical characteristics, outcomes, and risk factors for coronavirus disease 2019 (COVID-19) in 492 patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) during the Omicron wave. Methods: Data were retrospectively collected from patient charts and the electronic medical record systems at the First Affiliated Hospital of Zhejiang University School of Medicine between December 2022 and January 2023. Results: The median follow-up period of the entire cohort was 62 days. Myeloid malignancies (58.5%) and acute lymphocytic leukemia (30.5%) constituted the most common underlying disease. Among the 492 patients, 415, 67, and 10 exhibited mild, moderate, and severe COVID-19, respectively. The incidence of moderate-to-severe COVID-19 was 15.7%. The 60-day overall survival and complete resolution rates were 98.1% and 80.6%, respectively. The risk factors for moderate-to-severe COVID-19 included corticosteroid use within 3 months before diagnosis, <6 months interval between allo-HSCT and COVID-19 diagnosis, and antithymocyte globulin use for graft-versus-host disease prophylaxis. Conclusions: During the Omicron wave, patients with allo-HSCT demonstrated a low COVID-19-related mortality rate and high moderate-to-severe and prolonged disease incidence. Prevention in the early posttransplantation period is critical for allo-HSCT recipients receiving corticosteroids.

Psycho-Emotional Well-Being in Caregivers of People with Acquired Brain Injury: An Exploratory Study on the Human Immersion Model during the Omicron Wave.

The purpose of this study was to investigate the effects of a "human immersion model" (HIM) in improving psychological well-being in caregivers of patients with acquired brain injury (ABI) during the Omicron wave in Italy. Fifteen subjects affected by ABI, who attended our intensive neurorehabilitation unit from January to March 2022 and their caregivers were submitted to the HIM. This novel approach consisted of "real" long-lasting meetings between the patients and their careers in a hospital setting (1-72 h meeting per week for 8 weeks). Each ABI caregiver was assessed through the administration of a short psychometric battery before starting the first immersion session with their family member and at the end of the HIM. We found significant changes in the caregivers' scores analyzed for anxiety, as per SAS (p < 0.0007, d = 1.02), burden and stress (ZBI-22; p < 0.001, d = 0.65), and emotive intelligence (TEIQue-SF; p < 0.0007, d = 0.82). Our data suggest that the HIM may be useful to promote ABI caregivers' psycho-emotional well-being in the context of critical periods such as the COVID-19 pandemic.

A multicentre study on the clinical characteristics of newborns infected with coronavirus disease 2019 during the omicron wave.

Objective: To investigate the clinical characteristics and outcomes of newborns infected with coronavirus disease 2019 (COVID-19) during the Omicron wave. Methods: From December 1, 2022, to January 4, 2023, clinical data were collected from neonates with COVID-19 who were admitted to 10 hospitals in Foshan City, China. Their epidemiological histories, clinical manifestations and outcomes were analysed. The neonates were divided into symptomatic and asymptomatic groups. The t test or χ2 test was used for comparisons between groups. Results: A total of 286 children were diagnosed, including 166 males, 120 females, 273 full-term infants and 13 premature infants. They were 5.5 (0-30) days old on average when they were admitted to the hospital. These children had contact with patients who tested positive for COVID-19 and were infected through horizontal transmission. This study included 33 asymptomatic and 253 symptomatic patients, among whom 143 were diagnosed with upper respiratory tract infections and 110 were diagnosed with pneumonia. There were no severe or critical patients. Fever (220 patients) was the most common clinical manifestation, with a duration of 1.1 (1-6) days. The next most common clinical manifestations were cough with nasal congestion or runny nose (4 patients), cough (34 patients), poor appetite (7 patients), shortness of breath (15 patients), and poor general status (1 patient). There were no significant abnormalities in routine blood tests among the neonates infected with COVID-19 except for mononucleosis. However, compared with the asymptomatic group, in the symptomatic group, the leukocyte and neutrophil granulocyte counts were significantly decreased, and the monocyte count was significantly increased. C-reactive protein (CRP) levels were significantly increased (≥10 mg/L) in 9 patients. Myocardial enzyme, liver function, kidney function and other tests showed no obvious abnormalities. Conclusions: In this study, neonates infected with the Omicron variant were asymptomatic or had mild disease. Symptomatic patients had lower leucocyte and neutrophil levels than asymptomatic patients.

Disease Course, Management and Outcomes in Kidney Transplant Recipients with SARS-CoV-2 Infection during the Omicron-Variant Wave: A Single-Center Experience.

BACKGROUND: Since December 2019, kidney transplant recipients (KTRs) have experienced a great impact of the coronavirus disease 2019 (COVID-19) pandemic, with a higher risk of morbidity and mortality compared to the general population. Preliminary data in KTRs suggest that the Omicron variant, which has been dominant since December 2021, is more infectious than the previous ones but is associated with reduced risk of severity and low lethality rates. The purpose of our study was to assess the disease course and outcomes of the SARS-CoV-2 infection in KTRs during the Omicron-surge. METHODS: This retrospective study included 451 KTRs diagnosed with SARS-CoV-2 infection between 1 December 2021 and 30 September 2022. Demographic and clinical characteristics at the time of infection, vaccination data, treatment, clinical course, and outcomes were recorded and analyzed. RESULTS: Mean age was 51.8 ± 13.7 years with a male predominance (61.2%). The majority (76.1%) were vaccinated with at least three doses of the available mRNA vaccines, although serology revealed low anti-SARS-CoV-2 antibody titers before infection (33 [3.3-1205] AU/mL). Only 6% of the patients experienced moderate-severe disease. Accordingly, there was low prevalence of adverse outcomes, such as SARS-CoV-2-related hospitalization (11.3%) and death (0.9%). Multivariate analysis revealed that only age significantly increased the risk of SARS-CoV-2-related hospitalization. CONCLUSIONS: During the Omicron wave, the clinical course of the SARS-CoV-2 infection in KTRs has substantially changed, with lower rates of moderate and severe disease and a low prevalence of adverse outcomes. Prospective clinical trials are warranted to further elucidate the evolving pathogenesis, management, and long-term outcomes of COVID-19 in such high-risk populations.

Epidemic Features of COVID-19 and Potential Impact of Hospital Strain During the Omicron Wave - Australia, 2022.

What is already known about this topic?: Hospitals have experienced a surge in admissions due to the increasing number of Omicron cases. Understanding the epidemiological features of coronavirus disease 2019 (COVID-19) and the strain it places on hospitals will provide scientific evidence to help policymakers better prepare for and respond to future outbreaks. What is added by this report?: The case fatality rate of COVID-19 was 1.4 per 1,000 persons during the Omicron wave. Over 90% of COVID-19-related deaths occurred in individuals aged 60 years or older, with pre-existing chronic conditions such as cardiac conditions and dementia, particularly among males aged 80 years or older. What are the implications for public health practice?: Public health policy is essential for preparing and preserving medical resource capacity, as well as recruiting additional clinicians and front-line staff in hospitals to address the increased demand. High-risk individuals should be prioritized for healthcare, vaccines, and targeted interventions.

Mathematical Modeling of SARS-CoV-2 Omicron Wave under Vaccination Effects.

Over the course of the COVID-19 pandemic millions of deaths and hospitalizations have been reported. Different SARS-CoV-2 variants of concern have been recognized during this pandemic and some of these variants of concern have caused uncertainty and changes in the dynamics. The Omicron variant has caused a large amount of infected cases in the US and worldwide. The average number of deaths during the Omicron wave toll increased in comparison with previous SARS-CoV-2 waves. We studied the Omicron wave by using a highly nonlinear mathematical model for the COVID-19 pandemic. The novel model includes individuals who are vaccinated and asymptomatic, which influences the dynamics of SARS-CoV-2. Moreover, the model considers the waning of the immunity and efficacy of the vaccine against the Omicron strain. This study uses the facts that the Omicron strain has a higher transmissibility than the previous circulating SARS-CoV-2 strain but is less deadly. Preliminary studies have found that Omicron has a lower case fatality rate compared to previous circulating SARS-CoV-2 strains. The simulation results show that even if the Omicron strain is less deadly it might cause more deaths, hospitalizations and infections. We provide a variety of scenarios that help to obtain insight about the Omicron wave and its consequences. The proposed mathematical model, in conjunction with the simulations, provides an explanation for a large Omicron wave under various conditions related to vaccines and transmissibility. These results provide an awareness that new SARS-CoV-2 variants can cause more deaths even if their fatality rate is lower.

Vaccination against SARS-CoV-2 in pregnancy during the Omicron wave: the prospective cohort study of the Italian obstetric surveillance system.

OBJECTIVES: Evidence on the effects of the SARS-CoV-2 Omicron variant on vaccinated and unvaccinated pregnant women is sparse. This study aimed to compare maternal and perinatal outcomes of women infected with SARS-CoV-2 during the Omicron wave in Italy, according to their vaccine protection. METHODS: This national prospective cohort study enrolled pregnant women with a positive SARS-CoV-2 nasopharyngeal swab within 7 days of hospital admission between 1 January and 31 May, 2022. Women who received at least one dose of vaccine during pregnancy and those who completed the vaccine cycle with the first booster were considered protected against moderate or severe COVID-19 (MSCD). A multivariable logistic regression model evaluated the association between vaccine protection and disease severity. Maternal age, educational level, citizenship, area of birth, previous comorbidities, and obesity were analysed as potential risk factors. RESULTS: MSCD was rare (41/2147, 1.9%; 95% CI, 1.4-2.6), and the odds of developing it were significantly higher among unprotected women (OR, 2.78; 95% CI, 1.39-5.57). Compared with protected women (n = 1069), the unprotected (n = 1078) were more often younger, with lower educational degrees, and foreigners. A higher probability of MSCD was found among women with previous comorbidities (OR, 2.86; 95% CI, 1.34-6.12) and those born in Asian countries (OR, 3.05; 95% CI, 1.23-7.56). The percentage of preterm birth was higher among women with MSCD compared with milder cases (32.0% [8/25] versus 8.4% [161/1917], p < 0.001) as well as the percentage of caesarean section (52.0% [13/25] versus 31.6% [606/1919], p 0.029). DISCUSSION: Although severe maternal and perinatal outcomes were rare, their prevalence was significantly higher among women without vaccine protection. Vaccination during pregnancy has the potential to protect both the mother and the baby, and it is therefore strongly recommended.