A comparative study of SARS-CoV-2 and common human coronavirus infections among children presenting to tertiary care in Oman.

OBJECTIVES: To compare clinical manifestations, laboratory characteristics, and outcomes of children presenting to tertiary care with SARS-CoV-2 or common human coronavirus (HCoV) infection. METHODS: Children 13 years of age or younger presenting in 2020 with SARS-CoV-2 and those presenting with HCoV between 2017 and 2019 were included. Clinical and laboratory features were compared using appropriate statistical tests. The study was conducted at the two main tertiary hospitals in Muscat, Oman. RESULTS: The study included 255 cases (131 SARS-CoV-2 and 124 HCoV). Median age was 1.7 years (interquartile range 0.5-5.6), and 140 patients (55%) were males. Among children with HCoV infection, diarrhea was less common compared to children with SARS-CoV-2 (4% vs 23%, P <0.001), while respiratory symptoms such as cough were more common (74% vs 31%, P <0.001). Intensive care admission was more frequent with SARS-CoV-2 infection compared to HCoV (22% vs 11%, P = 0.039). Three virus-related deaths were recorded, all of which occurred among patients with SARS-CoV-2 and multisystem inflammatory syndrome in children. CONCLUSION: Lower respiratory tract disease is more frequent among children with HCoV infection compared to SARS-CoV-2, while gastrointestinal symptoms are more frequent with SARS-CoV-2. Critical illness is more likely with SARS-CoV-2 infection, driven mostly by multisystem inflammatory syndrome in children.

Short and long-term immune changes in different severity groups of COVID-19 disease.

BACKGROUND: There are limited data on short- versus long-term changes in adaptive immune response across different COVID-19 disease severity groups. METHODS: A multicenter prospective study of 140 adult patients with COVID-19 (a total of 325 samples) were analyzed for inflammatory markers and lymphocyte subsets at presentation, week 2, and week 24. RESULTS: Inflammatory markers at presentation were higher in the critical/severe than in moderate and mild groups. A predominance of memory B cell response in the mild and moderate group was noted by week 2. In contrast, the immune system in the severe/critical group was dysfunctional, with expansion of exhausted CD8+ T cells and atypical memory B cells. By 24 weeks, there was a possible trend of normalization. CONCLUSION: There was substantial difference in the degree of inflammation and distribution of different B and T cell subsets in the different disease severity groups. Despite the initial dysfunctional immune response in the severe/critical group, a comparable memory B and CD8+ T cell responses to the mild group was achieved at 24 weeks.