Motamed Hajar, Siami Shadi, Abdan Zahra, Mozafari Faruq, Khazaei Sedigheh, Habibi Reza, Rezaeian Shahab, Heydarpour Fatemeh
Department of Pathology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Molecular Pathology Research Center, Imam Reza Hospital, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Clin Exp Vaccine Res. 2025 Jul;14(3):261-266. doi: 10.7774/cevr.2025.14.e24. Epub 2025 May 21.
The current novel coronavirus disease pandemic was declared by the World Health Organization in 2020. Considering the difference in the infection and mortality rates in healthcare workers in Iran compared to other countries, as well as the diversity of vaccines used and their effectiveness, this study was conducted to investigate the effect of coronavirus disease 2019 (COVID-19) vaccination on the viral loads and symptoms of healthcare workers.
In this retrospective cohort study, viral loads of first and breakthrough COVID-19 infections of Imam Reza and Mohammad Kermanshahi Hospital personnel were measured before and after full dose COVID-19 vaccination, through measuring delta cycle threshold (ΔCt), an inverse measure of viral load, from 2020 to 2021 in Kermanshah, Iran.
Polymerase chain reaction test results of 110 cases with an average age of 35.15±8.04 were compared. Female participants were 71 (64.5%), and the rest were male. Breakthrough viral loads were significantly lower than first infection (mean ΔCt, 22.04±4.59 vs. 26.61±3, p<0.001). Cough, fever, chills, and myalgia frequencies were significantly decreased in breakthrough infections (p<0.05), except for dyspnea. Gastrointestinal symptoms remained the same, and anosmia frequency increased in breakthrough infections. Viral loads based on vaccine type and clinical symptoms were significantly reduced (p<0.05).
Based on our findings, 2 doses of COVID-19 vaccination could be effective in reducing the viral loads and frequency of clinical symptoms in Iranian healthcare workers.
2020年世界卫生组织宣布了当前的新型冠状病毒病大流行。考虑到伊朗医护人员的感染率和死亡率与其他国家存在差异，以及所使用疫苗的多样性及其有效性，本研究旨在调查2019冠状病毒病（COVID-19）疫苗接种对医护人员病毒载量和症状的影响。
在这项回顾性队列研究中，通过测量2020年至2021年伊朗克尔曼沙赫伊玛目礼萨医院和穆罕默德·克尔曼沙希医院人员首次感染和突破性COVID-19感染的病毒载量，即通过测量作为病毒载量反向指标的ΔCt（delta循环阈值）来进行研究。
比较了110例平均年龄为35.15±8.04岁患者的聚合酶链反应检测结果。女性参与者有71人（64.5%），其余为男性。突破性感染的病毒载量显著低于首次感染（平均ΔCt，22.04±4.59对26.61±3，p<0.001）。突破性感染中咳嗽、发热、寒战和肌痛的频率显著降低（p<0.05），但呼吸困难除外。胃肠道症状保持不变，突破性感染中嗅觉丧失频率增加。基于疫苗类型和临床症状的病毒载量显著降低（p<0.05）。
根据我们的研究结果，两剂COVID-19疫苗接种可有效降低伊朗医护人员的病毒载量和临床症状频率。
