Browsing by Author "Haji, Alhan"

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    Adverse events following administration of COVID-19 vaccines in Saudi Arabia
    (Springer Nature, 2022-11-15) Alqahtani, Saleh; Jokhdar, Hani; Al‑Tawfiq, Jaffar A.; Al‑Otaibi, Salah; Assiri, Abdullah; Almudarra, Sami; Alabdulkareem, Khaled; Haji, Alhan; Medicine, School of Medicine
    Previous studies investigated the frequency of different adverse events of COVID-19 vaccines. However, this study compares these adverse events between the two main COVID-19 vaccines used in Saudi Arabia (Pfizer-BioNTech and Oxford-AstraZeneca) using telemedicine technology. A cross-sectional study was conducted among 958 individuals, 7 days after receiving either Pfizer-BioNTech or Oxford-AstraZeneca vaccines during June 2021. Immediate adverse events were reported by 1.04% and 2.09% for Pfizer-BioNTech and Oxford-AstraZeneca vaccines, respectively, with no serious events. Recipients of Pfizer-BioNTech vaccine had a higher percentage of local adverse events (24.8% versus 9.8% in AstraZeneca vaccine). The most common reported systemic adverse events in both vaccines respectively were general fatigue (23.1% and 25.1%), fever (18.5% and 27.2%), myalgia (20.6% and 20.3%), and headache (15.2% and 17.2%). No significant difference was recorded between both vaccines regarding overall systemic adverse events; however, they were more frequent following the first dose of AstraZeneca vaccine compared to Pfizer-BioNTech vaccine, while the reverse was observed for the second dose. Adverse events were more frequent in females and younger age groups for both vaccines. Most of systemic and local adverse events were mild in nature. Further cohort studies are recommended to investigate the long-term adverse events of COVID-19 vaccines.
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    Does ChAdOx1-S and BNT162b2 heterologous prime-boost vaccination trigger higher rates of vaccine-related adverse events?
    (Elsevier, 2023) Haji, Alhan; Alkattan, Abdallah; Mahmoud, Nagla; Elkagam, Elfadil; Hassanein, Mustafa; Alfaifi, Amal; Al-Tawfiq, Jaffar A.; Alabdulkareem, Khaled; Jokhdar, Hani; Radwan, Nashwa; Medicine, School of Medicine
    Background: There has been significant international interest in heterologous prime-boost COVID-19 vaccination. However, it is linked with different intensity and frequency of adverse events. This study aimed to assess the safety of ChAdOx1-S and BNT162b2 vaccines when given as heterologous prime-boost vaccination in Saudi Arabia. Methods: A cross-sectional study was conducted during the period October 2021 to March 2022. The study included two groups of people based on the type of vaccination regimen. The first group (heterologous) was subjected to different prime-boost vaccination schedules irrespective of the prime and boost vaccine types. The second group included people vaccinated with the same type of COVID-19 vaccine (homologous). Results: The overall sample included 334 participants. Those included in the heterologous group were at about 1.5 fold -increased risk for developing local and systemic adverse events compared to the homologous group. Fever, headache, and vomiting were significantly more frequent among the heterologous group compared to the homologous group (p-value<0.05). In both groups, more than half of the recorded adverse events were mild/moderate in severity. Conclusion: Heterologous prime-post vaccination is associated with a slightly increased risk for the development of local and systemic adverse events compared to the homologous regimen. However, most of these adverse events are mild/moderate in nature and recede within two days with no serious adverse events documented.