Background The ChAdOx1 nCoV-19 (AZD1222) vaccine has been approved for emergency use by the UK regulatory authority, Medicines and Healthcare products Regulatory Agency, with a regimen of two standard doses given with an interval of 4–12 weeks. The planned roll-out in the UK will involve vaccinating people in high-risk categories with their first dose immediately, and delivering the second dose 12 weeks later. Here, we provide both a further prespecified pooled analysis of trials of ChAdOx1 nCoV-19 and exploratory analyses of the impact on immunogenicity and efficacy of extending the interval between priming and booster doses. In addition, we show the immunogenicity and protection afforded by the first dose, before a booster dose has been offered. Methods We present data from three single-blind randomised controlled trials—one phase 1/2 study in the UK (COV001), one phase 2/3 study in the UK (COV002), and a phase 3 study in Brazil (COV003)—and one double-blind phase 1/2 study in South Africa (COV005). As previously described, individuals 18 years and older were randomly assigned 1:1 to receive two standard doses of ChAdOx1 nCoV-19 (5 × 10 10 viral particles) or a control vaccine or saline placebo. In the UK trial, a subset of participants received a lower dose (2·2 × 10 10 viral particles) of the ChAdOx1 nCoV-19 for the first dose. The primary outcome was virologically confirmed symptomatic COVID-19 disease, defined as a nucleic acid amplification test (NAAT)-positive swab combined with at least one qualifying symptom (fever ≥37·8°C, cough, shortness of breath, or anosmia or ageusia) more than 14 days after the second dose. Secondary efficacy analyses included cases occuring at least 22 days after the first dose. Antibody responses measured by immunoassay and by pseudovirus neutralisation were exploratory outcomes. All cases of COVID-19 with a NAAT-positive swab were adjudicated for inclusion in the analysis by a masked independent endpoint review committee. The primary analysis included all participants who were SARS-CoV-2 N protein seronegative at baseline, had had at least 14 days of follow-up after the second dose, and had no evidence of previous SARS-CoV-2 infection from NAAT swabs. Safety was assessed in all participants who received at least one dose. The four trials are registered at ISRCTN89951424 (COV003) and ClinicalTrials.gov , NCT04324606 (COV001), NCT04400838 (COV002), and NCT04444674 (COV005). Findings Between April 23 and Dec 6, 2020, 24 422 participants were recruited and vaccinated across the four studies, of whom 17 178 were included in the primary analysis (8597 receiving ChAdOx1 nCoV-19 and 8581 receiving control vaccine). The data cutoff for these analyses was Dec 7, 2020. 332 NAAT-positive infections met the primary endpoint of symptomatic infection more t...

Background:The Pfizer-BioNTech (BNT162b2) and the Oxford-AstraZeneca (ChAdOx1 nCoV-19) COVID-19 vaccines have shown promising safety and acceptability. However, COVID-19 vaccine side effects play an essential role in public vaccine confidence. We aimed to study the side effects of these COVID-19 vaccines. Methods: A randomized, cross-sectional descriptive study was conducted between March and May of 2021. In total, 330 participants among the King Khalid University community in the Aseer region of the Kingdom of Saudi Arabia reported their side effects following the COVID-19 vaccine. A questionnaire was designed and validated to collect the participants' demographic data and COVID-19-related symptoms after COVID-19 vaccine injection. Results: Symptoms associated with COVID-19 were reported by 226 participants (68.5%). The most common side effects reported by the participants were fever (n = 136, 41.2%), fatigue (n = 119, 36.1%), headache (n = 86, 24.2%), malaise (n = 121, 36.7%), myalgia (n = 121, 36.7%), and muscle and joint pain (n = 76, 23%). Of the participants, 5.1% became infected with COVID-19 after vaccination. Symptoms were significantly more common in males than in females (p = 0.006). Conclusion:The incidence of COVID-19 vaccination side effects in the Aseer region, Kingdom of Saudi Arabia, was consistent with the manufacturers' data. The most common post-vaccination symptoms reported by the participants were fever, myalgia, malaise, fatigue, muscle and joint pain, and headache. The results of this study showed significant variation in adverse events between Pfizer-BioNTech and Oxford-AstraZeneca COVID-19 vaccines. Healthcare providers and recipients of vaccines can be more confident about the safety of Pfizer-BioNTech and Oxford-AstraZeneca COVID-19 vaccines.

Background and Objective:The Kingdom of Saudi Arabia has exerted great efforts to prevent the spread of COVID-19. This research aims to scrutinize the outlook, awareness, and customs of Saudi undergraduate students regarding COVID-19. Methods: The current cross-sectional study comprises 178 undergraduate students in the Faculty of Applied Medical Sciences. The data were collected from online Google form questionnaires. The differences were picked out of the questionnaires, and the mean scores of the differences were duly assessed. The variables associated with knowledge, attitude, and practice toward COVID-19 were evaluated; moreover, a comparative study was conducted on these variables in different faculty departments. ANOVA, Student's t-test, and binary logistic regression analysis were used to assess the data on knowledge, attitude, and practice. Results: Most of the undergraduate students were well acquainted with COVID-19. We obtained the mean knowledge score for COVID-19 to be 3.08 ± .82 (range: 1-5), indicating good knowledge. The attitude means the score was 3.02 ± .61 (range: 0-4), implying good positive attitudes. On assessing the mean score of practices, it was found 5 ± .47 (range: 0-7), pointing towards perfect practices. There were no significant differences between males and females regarding knowledge, attitudes, and practice toward COVID-19 (p-value < 0.05). Conclusion: Students of Applied Medical Sciences are knowledgeable about COVID-19. Health education programs should be focused on protection and safety from COVID-19 for Applied Medical Sciences students, especially Medical Rehabilitation Sciences and Radiology. Hand hygiene awareness programs must be conducted for undergraduate students. Infection control should be part of the undergraduate applied for medical sciences curriculum program.

Smoking is well known to be correlated with cardiovascular abnormalities, in particular atherosclerosis and heart diseases. This article investigates the effect and relationship of smoking tobacco on the thickness of the intima–media (IMT) belonging to the common carotid arteries (CCAs), and also blood concentration of the lipid profile (LP), mainly the total cholesterol, High Density Lipoprotein (HDL), Low Density Lipoprotein (LDL) and also triglycerides. Nineteen male tobacco smokers and thirty-five healthy male non-smoking Saudi participants were involved in this study after obtaining their informed consent. An ultrasound and a spectrophotometer were used to determine the IMTs and lipid parameters, respectively. The thicknesses of the smokers’ right (RCA) and left carotid (LCA) arteries (0.72 and 0.7 mm, respectively) were significantly greater than the thicknesses of the arteries of the non-smokers (0.58 and 0.62 mm, respectively) (p-value = 0.005 and 0.04). Insignificant differences between the means of the other parameters in the two groups were studied. Smoking is a risk factor for stroke, because it significantly increases the IMTs of both the right and left carotid arteries.

Hypertension is an independent risk factor for cardiovascular diseases. The accurate evaluation of cardiovascular risk is of paramount importance in the management of hypertensive patients. Conventional echocardiographic methods have provided the assessment of left ventricular systolic function and mass for many years. Tissue Doppler imaging, 3-dimensional echocardiography, and speckle tracking echocardiography are newer echocardiographic modalities for the left ventricular systolic function and mass quantification. The major emphasis of this review is to evaluate the left ventricular systolic function and mass by conventional and newly developed echocardiographic in hypertensive patients.