Critical illness in COVID-19 is attributed to an exaggerated host immune response. Since neutrophils are the major component of innate immunity, we hypothesize that the quantum of activated neutrophils in the blood may predict an adverse outcome. In a retrospective study of 300 adult patients with confirmed COVID-19, we analyzed the impact of neutrophil activation (NEUT-RI), interleukin-6 (IL-6) and the established clinical risk factors of age, diabetes, obesity and hypertension on the clinical outcome. Significant predictors of the need for mechanical ventilation were NEUT-RI (Odds Ratio (OR) = 1.22, P < 0.001), diabetes (OR = 2.56, P = 0.00846) and obesity (OR = 6.55, P < 0.001). For death, the significant predictors were NEUT-RI (OR = 1.14, P = 0.00432), diabetes (OR = 4.11, P = 0.00185) and age (OR = 1.04, P = 0.00896). The optimal cut-off value for NEUT-RI to predict mechanical ventilation and death was 52 fluorescence intensity units (sensitivity 44%, specificity 88%, area under the curve 0.67 and 44%, 86%, 0.64, respectively). This finding supports an aberrant neutrophil response in COVID-19, likely due to uncontained viral replication, tissue hypoxia and exacerbated inflammation, introduces a novel biomarker for rapid monitoring and opens new avenues for therapeutic strategies.

Background and Objectives: Nucleic acid‐amplification testing (NAT) is used for screening blood donations/donors for blood‐borne viruses. We reviewed global viral NAT characteristics and NAT‐yield confirmatory testing used by blood operators.Materials and Methods: NAT characteristics and NAT‐yield confirmatory testing used during 2019 was surveyed internationally by the International Society of Blood Transfusion Working Party Transfusion‐Transmitted Infectious Diseases. Reported characteristics are presented herein.Results: NAT was mainly performed under government mandate. Human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV) NAT was performed on all donors and donation types, while selective testing was reported for West Nile virus, hepatitis E virus (HEV), and Zika virus. Individual donation NAT was used for HIV, HCV and HBV by ~50% of responders, while HEV was screened in mini‐pools by 83% of responders performing HEV NAT. Confirmatory testing for NAT‐yield samples was generally performed by NAT on a sample from the same donation or by NAT and serology on samples from the same donation and a follow‐up sample.Conclusion: In the last decade, there has been a trend towards use of smaller pool sizes or individual donation NAT. We captured characteristics of NAT internationally in 2019 and provide insights into confirmatory testing approaches used for NAT‐yields, potentially benefitting blood operators seeking to implement NAT.

There are limited data on short- versus long-term changes in adaptive immune response across different COVID-19 disease severity groups. 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. 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. 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.

Routine blood donor screening of human T-cell lymphotropic virus (HTLV) has been practiced in Oman since 2017. Limited data exists on HTLV seroprevalence among Omanis. This study aims to determine the seroprevalence of HTLV-I/II among blood donors attending a hospital-based blood bank to assess the need for a universal versus targeted screening. We conducted a retrospective review of blood donors’ results attending a hospital blood bank between January 2017 and February 2020. Blood samples were screened for HTLV-I/II antibodies using ARCHITECT i2000SR. Reactive samples underwent further testing by immunoblot assay (MP Diagnostics HTLV Blot 2.4). Age, gender, and nationality were assessed. All components manufactured at the blood bank undergo leukoreduction before storage. A total of 24 469 first-time blood donors were screened for HTLV antibodies. Most participants were male (n = 22 186, 90.7%), and the majority were Omani (n = 22 711, 92.8%). The age range was 18 to 64 years, with a median of 32 years. The seroreactivity rate was 0.2% (43; 95% CI: 0.12–0.23). Confirmatory testing by immunoblot revealed three indeterminate results (7.9%), of which two were Omani and one non-Omani donor, and the remaining 40 seroreactive donors tested negative. Our study revealed zero seroprevalence of confirmed HTLV among blood donors. The continuation of universal screening for first-time donors is a standard of care. With universal leukoreduction at Sultan Qaboos University Hospital and a very low risk of HTLV in Oman’s population, the need for screening regular donors can be reconsidered if these findings are confirmed on a larger scale involving other blood banks in Oman.

To estimate the incidence, risk factors, and outcome of cytomegalovirus (CMV) infection during the first year following hematopoietic stem cell transplant (HSCT) among Omani patients. This retrospective study included allogenic HSCT recipients between January 2006 and December 2018. We investigated the possible factors associated with CMV infection and CMV impact on one-year mortality. Among 556 recipients of allogenic HSCT, 308 (55.4%) were male, the median age was 12 years, and 366 (65.8%) had benign conditions. One-year after transplants, the prevalence of CMV infection was 59.4%, and that of CMV disease was 1.8%. Multivariate analyses revealed significant relationships between CMV infection and haploidentical transplant (p = 0.006), graft versus host disease (p = 0.013), myeloablative conditioning (p = 0.001), and patient age ≥ 12 years (p < 0.001). CMV infection was associated with an increased risk of one-year mortality (p = 0.001). One-year overall mortality was 8.3%. The incidence of CMV infection in this Omani cohort was comparable with earlier findings, but the disease incidence and overall mortality were lower. Older age, haploidentical transplant, myeloablative conditioning, and graft versus host disease were significantly associated with a higher risk of CMV infection. In addition, CMV infection was associated with an increased risk of overall mortality in the first year post-transplant. Our findings support early initiation of preemptive therapy at low-level CMV viremia.