ABSTRACT
BACKGROUND: Within a year of the SARS-CoV-2 pandemic, vaccines inducing a robust humoral and cellular immune response were implemented worldwide. However, emergence of novel variants and waning vaccine induced immunity led to implementation of additional vaccine boosters. METHODS: This prospective study evaluated the temporal profile of cellular and serological responses in a cohort of 639 SARS-CoV-2 vaccinated participants, of whom a large proportion experienced a SARS-CoV-2 infection. All participants were infection naïve at the time of their first vaccine dose. Proportions of SARS-CoV-2 Spike-specific T cells were determined after each vaccine dose using the Activation Induced Markers (AIM) assay, while levels of circulating SARS-CoV-2 antibodies were determined by the Meso Scale serology assay. RESULTS: We found a significant increase in SARS-CoV-2 Spike-specific CD4+ and CD8+ T cell responses following the third dose of a SARS-CoV-2 mRNA vaccine as well as enhanced CD8+ T cell responses after the fourth dose. Further, increased age was associated with a poorer response. Finally, we observed that SARS-CoV-2 infection boosts both the cellular and humoral immune response, relative to vaccine-induced immunity alone. CONCLUSION: Our findings highlight the boosting effect on T cell immunity of repeated vaccine administration. The combination of multiple vaccine doses and SARS-CoV-2 infections maintains population T cell immunity although with reduced levels in the elderly.
ABSTRACT
Introduction: Thoracic ultrasound (TUS) has proven useful in the diagnosis, risk stratification and monitoring of disease progression in patients with coronavirus disease 2019 (COVID-19). However, utility in follow-up is poorly described. To elucidate this area, we performed TUS as part of a 12-month clinical follow-up in patients previously admitted with COVID-19 and correlated findings with clinical assessment and pulmonary function tests. Methods: Adult patients discharged from our hospital following admission with COVID-19 during March to May 2020 were invited to a 12-month follow-up. Enrolled patients were interviewed regarding persisting or newly developed symptoms in addition to TUS, spirometry and a 6-min walk test. Patients were referred to high-resolution computed tomography (HRCT) of the lungs if suspicion of pulmonary fibrosis was raised. Results: Forty patients were enrolled in the study of whom had 13 developed acute respiratory distress syndrome (ARDS) during admission. Patients with ARDS were more prone to experience neurological symptoms at follow-up (p = 0.03) and showed more B-lines on TUS (p = 0.008) but did not otherwise differ significantly in terms of pulmonary function tests. Four patients had pathological findings on TUS where subsequent diagnostics revealed that two had interstitial lung abnormalities and two had heart failure. These four patients presented with a significantly lower diffusing capacity of lung for carbon monoxide (p=0.03) and 6-min walking distance (p=0.006) compared to the remaining 36 patients without ultrasound pathology. No significant difference was observed in spirometry values of % of predicted FEV1 (p=0.49) or FVC (p=0.07). No persisting cardiovascular pathology was observed in patients without ultrasonographic pathology. Conclusion: At 12-month after admission with COVID-19, a follow-up combining TUS, clinical assessment, and pulmonary function tests may improve the selection of patients requiring further diagnostic investigations such as HRCT or echocardiography.
ABSTRACT
INTRODUCTION: COVID-19 is associated with a risk of severe pneumonia and acute respiratory distress syndrome (ARDS), requiring treatment at an intensive care unit (ICU). Since clinical deterioration may occur rapidly, a simple, fast, bedside, non-invasive method for assessment of lung changes is warranted. The primary aim of this study was to investigate whether lung ultrasound (LUS) findings within 72 hours of admission were predictive of clinical deterioration in hospitalized patients with confirmed Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). METHODS: Patients admitted to a dedicated COVID-19 unit were subject to daily LUS examinations. Number of present consolidations and pleural effusions were registered and a Mongodi score was calculated. These findings were correlated with initial chest x-ray and clinical deterioration, defined as ICU-admission, ARDS diagnosis, death. RESULTS: In total, 29 of 83 patients had LUS performed during admission, 18 within 72 h of admission. Of these, four patients died during admission, six were transferred to the ICU and 13 were diagnosed with ARDS. Initial Mongodi-score did not differ significantly between patients with and without clinical deterioration (p = 0.95). Agreement between initial LUS and chest x-ray findings were fair with Cohen's Kappa at 0.21. CONCLUSION: LUS performed within 72 h in patients admitted to a dedicated COVID-19 unit could not predict ARDS, ICU admission or death. However, consecutive investigations may be of value, as sudden substantial changes may herald disease progression, enabling earlier supplementary diagnostics and treatment initiation.
