Age-related differences in SARS-CoV-2 binding factors: An explanation for reduced susceptibility to severe COVID-19 among children?

Clinical Characteristics and Analysis of Associated Risk Factors in Patients with Severe and Non-Severe COVID-19 Infection

Objective

Our aim was to highlight the clinical characteristics and determine the risk factors associated with severe and non-severe COVID-19 infection.

Study Method

A retrospective review was conducted on clinical data obtained from patients with COVID-19 infection, admitted to the emergency department between November 2022 and January 2023. Total of 1684 participants were categorized into severe (312 cases,18.53%) and non-severe (1,372 cases,81.47%) cohorts. Logistic regression was utilized for multivariate analysis, with a P-value less than 0.05 signifying a significant difference between the groups.

Results

The study consisted of 952 males (56.53%) and 732 females (43.47%) participants. The age distribution ranged from 18 to 93 years in both cohorts. There were statistically significant differences between the clinical symptoms of the severe and non-severe cohorts (P < 0.05). According to the multivariate statistical analysis, patients with more pronounced clinical manifestations had significantly elevated values related to age(P < 0.05), diabetes(P < 0.01), hypertension(P < 0.01), C-reactive protein (CRP) (P < 0.05), and lactate dehydrogenase (LDH) (P < 0.01) as compared to those presenting with milder symptoms.

Conclusion

The primary clinical presentations in both the cohorts were mostly similar. Predominant factors contributing to the severity of COVID-19 infection were age, diabetes, hypertension, elevated CRP levels, and increased LDH.

Proteomic profiling identifies biomarkers of COVID-19 severity

SARS-CoV-2 infection remains a major public health concern, particularly for the aged and those individuals with co-morbidities at risk for developing severe COVID-19. Understanding the pathogenesis and biomarkers associated with responses to SARS-CoV-2 infection remain critical components in developing effective therapeutic approaches, especially in cases of severe and long-COVID-19. In this study blood plasma protein expression was compared in subjects with mild, moderate, and severe COVID-19 disease. Evaluation of an inflammatory protein panel confirms upregulation of proteins including TNFβ, IL-6, IL-8, IL-12, already associated with severe cytokine storm and progression to severe COVID-19. Importantly, we identify several proteins not yet associated with COVID-19 disease, including mesothelin (MSLN), that are expressed at significantly higher levels in severe COVID-19 subjects. In addition, we find a subset of markers associated with T-cell and dendritic cell responses to viral infection that are significantly higher in mild cases and decrease in expression as severity of COVID-19 increases, suggesting that an immediate and effective activation of T-cells is critical in modulating disease progression. Together, our findings identify new targets for further investigation as therapeutic approaches for the treatment of SARS-CoV-2 infection and prevention of complications of severe COVID-19.

Timing of general anesthesia for pediatric patients recovering from COVID-19: a prospective cohort study

OBJECTIVE

To explore the timing of general anesthesia for pediatric patients who have recovered from novel coronavirus infection and summarize anesthesia-related complications.

METHODS

We summarized the perioperative management of children under 14 years of age who underwent general anesthesia in our hospital according to national epidemic prevention and control requirements. We compared the incidence of postoperative pulmonary complications within 2 weeks (Group A), 3-4 weeks (Group B), and 5-6 weeks (Group C) after COVID-19 recovery.

RESULTS

There were differences among the three groups in terms of decreased blood oxygen saturation (< 94%), secretions, and coughing during the PACU period. The risk of low blood oxygen saturation during PACU decreased as the time of COVID-19 recovery extended in the three groups. Compared to Group A, the risk of low blood oxygen saturation was lower in Group B. The presence of respiratory symptoms and a body temperature above 40℃ increased the risk of decreased blood oxygen saturation. The proportion of children aged 11-14 years and children with high fever experiencing decreased blood oxygen saturation during PACU was higher in Groups A and B. Among the three groups, children with respiratory symptoms and longer illness duration had a higher proportion of decreased blood oxygen saturation during PACU.

CONCLUSION

Pediatric patients who have recovered from COVID-19 for more than 2 weeks have a lower risk of postoperative complications after general anesthesia. For children with respiratory system symptoms or high fever, there is a higher risk of transient blood oxygen saturation decrease during PACU. For older children, those with high fever, respiratory system symptoms, or longer illness duration, it is recommended to appropriately extend the time from COVID-19 recovery to surgery.

Generation and characterization of a humanized ACE2 mouse model to study long-term impacts of SARS-CoV-2 infection

Although the COVID-19 pandemic has officially ended, the persistent challenge of long-COVID or post-acute COVID sequelae (PASC) continues to impact societies globally, highlighting the urgent need for ongoing research into its mechanisms and therapeutic approaches. Our team has recently developed a novel humanized ACE2 mouse model (hACE2ki) designed explicitly for long-COVID/PASC research. This model exhibits human ACE2 expression in tissue and cell-specific patterns akin to mouse Ace2. When we exposed young adult hACE2ki mice (6 weeks old) to various SARS-CoV-2 lineages, including WA, Delta, and Omicron, at a dose of 5 × 105 PFU/mouse via nasal instillation, the mice demonstrated distinctive phenotypes characterized by differences in viral load in the lung, trachea, and nasal turbinate, weight loss, and changes in pro-inflammatory cytokines and immune cell profiles in bronchoalveolar lavage fluid. Notably, no mortality was observed in this age group. Further, to assess the model's relevance for long-COVID studies, we investigated tau protein pathologies, which are linked to Alzheimer's disease, in the brains of these mice post SARS-CoV-2 infection. Our findings revealed the accumulation and longitudinal propagation of tau, confirming the potential of our hACE2ki mouse model for preclinical studies of long-COVID.

Management of patients with allergic diseases in the era of COVID-19

In the early days of the coronavirus disease 2019 (COVID-19) pandemic, allergic diseases, especially asthma, were considered to be risk factors for severe COVID-19 infection, hospitalization, and death. These concerns stemmed from the idea that individuals with allergic diseases are generally more susceptible to respiratory virus infections, which are major causes of exacerbation of allergic diseases. However, epidemiologic data with mechanistic studies showed that the associations between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and clinical outcomes of allergic diseases are complex and affected by diverse factors such as allergic disease severity, phenotypes, and control status with current medications. In addition, children generally have less severe clinical outcomes of COVID-19 than those of adults, which complicates the association between allergic diseases and COVID-19-related outcomes among them. The present review summarizes the potential association between allergic diseases and COVID-19-related outcomes and discusses the factors requiring consideration. The findings viewed herein will aid the management of allergic diseases in patients with SARS-CoV-2 infection and the establishment of medical polices for managing patients with allergic diseases.

HMGB1 in Pediatric COVID-19 Infection and MIS-C: A Pilot Study

OBJECTIVE

Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, a novel syndrome known as a multisystem inflammatory syndrome in children (MIS-C) was reported in previously healthy children. A possible pro-inflammatory molecule, high-mobility group box 1 (HMGB1), may be assumed to play an important role in the pathogenesis and clinical presentation of MIS-C. We described the clinical picture of patients with MIS-C and we also aimed to test and compare HMGB1 serum levels of MIS-C patients with those of patients with previous SARS-CoV2 infection and healthy children.

STUDY DESIGN

We determined HMGB1 levels by Western blot in 46 patients and divided them into three groups, namely, five patients with MIS-C (median age: 8.36 years), 20 children with a history of SARS-CoV-2 infection (median age: 10.45 years), and 21 healthy children (controls) (median age: 4.84 years), without evidence of respiratory infection in the last 3 months.

RESULTS

The median level of HMGB1 in the serum of five patients with MIS-C was found to be significantly higher compared with both patients with a recent history of COVID-19 (1,151.38 vs. 545.90 densitometric units (DU), p = 0.001) and control (1,151.38 vs. 320.33 DU, p = 0.001) groups. The HMGB1 level in MIS-C patients with coronary involvement had a slightly higher value with respect to patients without coronary dilatation (1,225.36 vs. 1,030.49 DU, p = 0.248). In two of the five children with MIS-C that performed a follow-up, the HMGB1 value decreased to levels that were superimposable to the ones of the control group.

CONCLUSION

The significantly high level of HMGB1 protein found in the serum of COVID-19 and patients with MIS-C supports its involvement in inflammatory manifestations, suggesting HMGB1 as a potential biomarker and therapeutic target in patients with severe illness.