Supplementary Material for: Adverse effects of COVID-19 vaccination in patients with Transfusion Dependent Thalassemia (TDT): an observational study from a tertiary care centre in Punjab, India.

Vaccination against SARS-CoV2 is the most important weapon in the arsenal in the battle against COVID-19. There is concern about an increased risk of adverse effects in patients with transfusion-dependent thalassemia (TDT), which affects vaccine acceptance. A predesigned questionnaire was used to evaluate adverse effects (local/systemic within 90 days after vaccination) in participants >18 years of age with TDT. A total of 100 patients received 129 vaccine doses. The mean age of the patients was 24.3 ± 5.7 years and M: F ratio of 1.6:1. Covishield (Serum Institute of India) was administered to 89% of the participants and Covaxin (Bharat Biotech Limited) to 11% of the participants. Adverse effects were documented in 62% of the respondents and were more pronounced after the first dose (52%) compared to the second dose (9%). The most frequent adverse effects were pain at the injection site (43%) and fever (37%). All adverse effects were mild and none of the participants required hospitalization. There were no differences in adverse effects among different vaccines, the presence or absence of comorbidities, blood groups, or ferritin levels. The SARS-CoV2 vaccine appears to be safe in patients with TDT.

针对SARS-CoV2（新型冠状病毒）的疫苗接种是对抗COVID-19（新型冠状病毒感染）战役中最为核心的防控手段。目前有研究担忧，依赖输血的地中海贫血（transfusion-dependent thalassemia, TDT）患者发生疫苗不良反应的风险会升高，这一顾虑对该人群的疫苗接种接受度产生了不利影响。本研究采用预先设计的问卷，对18岁以上的TDT患者在接种疫苗后90天内出现的局部或全身不良反应进行评估。共计100名患者完成了129剂次疫苗接种，患者的平均年龄为24.3±5.7岁，男女比例为1.6:1。其中89%的受试者接种了Covishield（Serum Institute of India，印度血清研究所）疫苗，11%的受试者接种了Covaxin（Bharat Biotech Limited，巴拉特生物技术有限公司）疫苗。62%的应答者报告出现了不良反应，且首剂接种后的不良反应发生率（52%）显著高于第二剂（9%）。最为频发的不良反应为接种部位疼痛（43%）与发热（37%）。所有不良反应均为轻度，无一例受试者需要住院治疗。不同疫苗类型、是否合并基础疾病、血型或铁蛋白水平之间，不良反应发生率均无显著差异。研究结果显示，SARS-CoV2疫苗在TDT患者中具备良好的安全性。