Abstract Objectives Peripheral blood abnormalities in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been fully elucidated. We report qualitative and quantitative peripheral blood findings in coronavirus disease 2019 (COVID-19) patients and compare them with a control group. Methods We reviewed electronic medical records, complete blood counts, peripheral blood smears, and flow cytometry data in 12 patients with SARS-CoV-2. These were compared with 10 control patients with symptoms suspicious for SARS-CoV-2 but who tested negative. Results No significant differences were noted in blood counts, except that absolute lymphopenia was present frequently in the control group (P < .05). Acquired Pelger-Huët anomaly (APHA) was noted in all COVID-19 cases, in most cases affecting over 5% of granulocytes. This contrasted with APHA in only 50% of control cases, affecting fewer than 5% of granulocytes in all cases (P < .05). Monolobate neutrophils were exclusive to COVID-19 cases. COVID-19 patients had greater frequency of plasmacytoid lymphocytes (P < .05). Flow cytometry data revealed absolute CD3+ T-cell count reduction in 6 of 7 patients; all of them required mechanical ventilation. Conclusions Lymphopenia was infrequent in our COVID-19 cohort; however, flow cytometric analysis revealed absolute T-cell count reduction in most cases. COVID-19 cases had significant APHA with monolobate neutrophils and plasmacytoid lymphocytes as compared to controls.

The possibility that interferon (IFN) and antibody could act together to reduce virus yields in infected cells was suggested by the simultaneous occurrence of IFN and antibody at infected sites. In the present in vitro studies, mixtures of IFNs and antibody acted synergistically to reduce virus yields in cultures infected with coxsackievirus A24, enterovirus 70, adenovirus, and herpes simplex virus. This synergistic reduction was observed in different cells and at different concentration of IFN and antibody. Although IFN and antibody acted synergistically against all viruses tested, the degree of synergism was dependent on the type of IFN or the virus. For example, IFN-P and antibody was 10 to 200 times more effective than