Does ChAdOx1-S and BNT162b2 heterologous prime-boost vaccination trigger higher rates of vaccine-related adverse events?

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.

Does ChAdOx1-S and BNT162b2 heterologous prime-boost vaccination trigger higher rates of vaccine-related adverse events?

Background There has been a significant international interest in heterologous prime-boost COVID-19 vaccination. However, it was 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. While the second group included people vaccinated with the same type of COVID-19 vaccine (homologous). Results The overall sample included was 334 participants. Those included in the heterologous group were at about 1.5 fold -increased risk for developing local and systematic adverse events compared to homologous group. Fever, headache, and vomiting were significantly more frequent among heterologous group compared to homologous one (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 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.

Protective Duration of ChAdOx1 and BNT162b2 Vaccines Against SARS-CoV-2 Infection.

BACKGROUND AND OBJECTIVE: A limited number of studies have addressed the protective duration of coronavirus disease 2019 (COVID-19) vaccines following primary and booster doses in Saudi Arabia. Therefore, this study aimed to evaluate the protective duration of primary and booster doses of BNT162b2 and ChAdOx1 COVID-19 vaccine batches in Saudi Arabia. METHODS: A cross-sectional study was conducted from 1 January to 31 December, 2021. The study included 53,354 people infected with severe acute respiratory syndrome coronavirus-2 2 weeks or more after receiving at least a primary vaccination of either the ChAdOx1 or BNT162b2 vaccine. RESULTS: The total median protective duration of both primary COVID-19 vaccinations was 134 days. Heterologous primary vaccination (ChAdOx1 followed by BNT162b2) showed a significantly higher median protective duration of 142 days. The results show that the total median protective duration of the first booster doses of COVID-19 vaccines was 57 days. ChAdOx1 batch code C1 was found to have the most extended protective duration of 173 days (range 163-192 days). CONCLUSIONS: The current study revealed that the median protective duration of ChAdOx1 and BNT162b2 COVID-19 primary vaccination regimens administered in Saudi Arabia in 2021 was 134 days and that heterologous primary vaccination (ChAdOx1→BNT162b2) exhibited a significantly higher protective duration than other vaccination regimens.

Post-COVID-19 syndrome: nature of symptoms and associated factors.

Aim: Post-COVID-19 syndrome is defined as continuous symptoms related to SARS-CoV-2 infection, which can persist for several weeks or months. Previous studies identified risk factors associated with post-COVID-19 syndrome, including female sex, hypertension, and allergic respiratory diseases. This study aims to investigate the frequency of this syndrome among Arabic patients. Subject and methods: A cross-sectional study was conducted from March to August 2022. The study included 520 Arabic patients with confirmed COVID-19 diagnosis, who were asked about possible symptoms persisting for ≥28 days. Results: Twenty-five percent (25%) of the included patients developed post-COVID-19 syndrome. The most common recorded symptoms were cough (32%), anosmia (32%), fatigue (28%), headache (19%), muscle pain (19%), and shortness of breath (17%). It was found that female sex, hospitalization due to initial COVID-19 infection, and the presence of chronic diseases were significant risk factors for developing post-COVID-19 syndrome. Conclusion: The study recorded post-COVID-19 syndrome among 25% of Arabic participants. Initial COVID-19 hospitalization, initial symptomatic COVID-19, and female sex were significant risk factors for developing post-COVID-19 syndrome. Supplementary Information: The online version contains supplementary material available at 10.1007/s10389-022-01802-3.

Post-COVID-19 syndrome: nature of symptoms and associated factors

Aim Post-COVID-19 syndrome is defined as continuous symptoms related to SARS-CoV-2 infection, which can persist for several weeks or months. Previous studies identified risk factors associated with post-COVID-19 syndrome, including female sex, hypertension, and allergic respiratory diseases. This study aims to investigate the frequency of this syndrome among Arabic patients. Subject and methods A cross-sectional study was conducted from March to August 2022. The study included 520 Arabic patients with confirmed COVID-19 diagnosis, who were asked about possible symptoms persisting for ≥28 days. Results Twenty-five percent (25%) of the included patients developed post-COVID-19 syndrome. The most common recorded symptoms were cough (32%), anosmia (32%), fatigue (28%), headache (19%), muscle pain (19%), and shortness of breath (17%). It was found that female sex, hospitalization due to initial COVID-19 infection, and the presence of chronic diseases were significant risk factors for developing post-COVID-19 syndrome. Conclusion The study recorded post-COVID-19 syndrome among 25% of Arabic participants. Initial COVID-19 hospitalization, initial symptomatic COVID-19, and female sex were significant risk factors for developing post-COVID-19 syndrome. Supplementary Information The online version contains supplementary material available at 10.1007/s10389-022-01802-3.

Adverse events following administration of COVID-19 vaccines in Saudi Arabia.

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.

COVID-19 vaccine acceptance: knowledge and beliefs.

Backgrounds: Vaccine acceptance varies across countries, generations, and the perceived personality of individuals. Investigating the knowledge, beliefs, and acceptability of COVID-19 vaccines among individuals is vital to ensuring adequate health system capacity and procedures and promoting the uptake of the vaccines. Results: A cross-sectional study was conducted from August 2021 to January 2022 in Saudi Arabia. The study included 281 residents to estimate their acceptance to receive COVID-19 vaccination. Around 70% of the included participants had a moderate to high COVID-19 vaccine acceptance rate during the data collection period. The risk increases to about two folds among undergraduates [OR 1.846 (1.034-3.296), p value = 0.036)] and increases to four folds among non-employed [OR 3.944 (2.310-6.737), p value = 0.001]. About 78% of participants with high and 44% with low COVID-19 vaccine acceptance (p value = 0.001) believed the vaccines were safe and effective. The belief that COVID-19 disease will be controlled within two years increased the risk for low vaccine acceptance by about two folds [OR 1.730 (1.035-2.891), p value = 0.035]. Good knowledge about COVID-19 vaccination significantly affected the acceptance rate (p value = 0.001). Conclusions: Several factors affect the intention of individuals to receive vaccines. Therefore, building good knowledge and health literacy through educational intervention programs, especially vaccine safety and effectiveness, is important for successful vaccination campaigns among the general population and ensuring control of the COVID-19 pandemic.