To study the effect of ‘Covishield’ vaccination on pre-donation platelet counts of plateletpheresis donors

INTRODUCTION: Approximately 55.52% of the Indian population had been fully vaccinated by Jan. 2022, since its first roll out on January 16, 2021. A few concerns were raised concerning the Covishield vaccination related to thrombotic thrombocytopenia. Apheresis-derived platelet concentrates are frequently required in a plethora of clinical situations and post-vaccination decrement of platelet counts might lead to increased deferral of the platelet-pheresis donors. Objectives. The aim of the study was to discover the effect of the Covishield vaccination on deferral rates of plateletpheresis donors. METHODS: Blood samples were collected from the potential platelet donors for the completion of the standard questionnaire for the complete blood count. The data collected were tabulated in the MS Excel spreadsheet and the biostatistical analysis was performed with the SPSS v23. A p-value of < 0.05 was taken as significant. We compared this data with age- and sex-matched controls. RESULTS: The mean age of cases and controls was 29.69 ± 8.57 and 30.15 ± 7.11, respectively. There was a significant difference in platelet counts of cases (188496.35 ± 72065.66/cumm) and controls (269524.50 ± 53981.60/cumm). Furthermore, donors who received one dose had higher platelet counts of 248676.47 ± 80075.24/cumm than those who received both doses of vaccine (179970.83 ± 66773.73/cumm) . The difference in deferral rates between the two groups was remarkable (34.7% vs. 0.9%, with the p-value < 0.001). CONCLUSION: Vaccination certainly increased the deferral rates of plateletpheresis donors due to low platelet counts. Average platelet counts were low in fully vaccinated individuals, however, the platelets returned to normal counts as the post-vaccination days progressed.