[Impact of Mild SARS-CoV-2 Infection on Hematological Parameters and Suitability of Apheresis Platelets Donation in Blood Donors]

Objective: To investigate the effects of mild SARS-CoV-2 infection on hematological parameters of adult blood donors and the suitability of apheresis platelet donation, the changes of the hematological parameters in blood donors with mild infection of the SARS-CoV-2 Omicron variant strain were evaluated.

Methods: Seventy-two blood donors with mild COVID-19 symptoms who donated consecutive apheresis platelets for 3 times from December 2022 to January 2023, 42 cases among which were included in the infection-positive group, and 30 cases in the suspected infection group. Forty-two donors un-vaccinated against SARS-CoV-2, un-infected, and donated three consecutive apheresis platelets from October to November 2022 were included in the control group. The changes of blood routine testing in the positive group and the suspected infection group were retrospectively compared before (Time1) and after (Time2 and Time3) the onset of symptoms, three consecutive times (Time1, Time2, Time3) in the control group by repeated measures analysis of variance. The Bayesian discriminant method was used to establish a discriminant equation to determine whether the recent infection of SARS-CoV-2 occurred or not.

Results: Simple effect of the number times of tests in the positive and suspected infection groups was significant（ F_{infection-positive group}=6.98, P < 0.001, partial η²=0.79, F_{suspected infection group}=4.31, P < 0.001, partial η²=0.70）. The positive group and the suspected infection group had lower RBC, HCT, and HGB, and higher PLT and PCT at Time2 compared to Time1 and Time3(P < 0.05). The positive group and the suspected infection group showes RDW-CV and RDW-SD at Time3 higher than Time1 and Time2 (P < 0.001). The simple effect of the number times of tests in the control group was not significant ( F=0.96, P =0.55, partial η²=0.34). The difference of the whole blood count parameters in the control group for three times was not statistically significant (P >0.05). We established a discriminant equation to determine whether the recent infection of SARS-CoV-2 occurred or not. The equation had an eigenvalue of 0.22, a canonical correlation of 0.43 (χ²=27.81, P < 0.001), and an analysis accuracy of 72.9%.

Conclusion: The hematological indicators of RBC, HCT, HGB, PLT, PCT, RDW-CV and RDW-SD in blood donors who had infected with mild COVID-19 showed dynamic changes. The discriminant equation for whether they are infected recently with COVID-19 has a high accuracy rate.