Seroprevalence of antibodies to SARS-CoV-2 among blood donors in the early month of the pandemic in Saudi Arabia

Background: Serologic testing provides better understanding of SARS-CoV-2 prevalence and its transmission. This study was an investigation of the prevalence of antibodies to SARS-CoV-2 among blood donors in Saudi Arabia. Objective: To estimate the seroprevalence of anti-SARS-CoV-2 antibodies among blood donors in Saudi Arabia during the early phase of the COVID-19 pandemic. Methods: Serology results and epidemiological data were analyzed for 837 adult blood donors, with no confirmed SARS-CoV-2 infection, in Saudi Arabia from 20th to 25th May 2020. Seroprevalence was determined using electrochemical immunoassay to detect anti-SARS-CoV-2 antibodies. Results: The overall seroprevalence of anti-SARS-CoV-2 antibodies was 1.4% (12/837). Non-citizens had higher seroprevalence compared with citizens (OR 13.6, p = 0.001). Secondary education was significantly associated with higher seroprevalence compared with higher education (OR 6.8, p = 0.005). The data showed that the highest seroprevalence was in Makkah (8.1%). Uisng Makkah seroprevalence as the reference, the seroprevalence in other areas was: Madinah 4.1% (OR 0.48, 95% CI 0.12-1.94), Jeddah 2.3% (OR 0.27, 95% CI 0.31-2.25), and Qassim 2.9 % (OR 0.34, 95% CI 0.04-2.89) and these were not statistically different from seroprevalence in the Makkah region. Conclusions: At the early months of the COVID-19 pandemic in Saudi Arabia, the seroprevalence of antibodies to SARS-CoV-2 among blood donors was low, but was higher among non-citizens. These findings may indicate that non-citizens and less educated individuals may be less attentive to preventive measures. Monitoring seroprevalence trends over time require repeated sampling

Seroprevalence of SARS-CoV-2 (COVID-19) among Healthcare Workers in Saudi Arabia: Comparing Case and Control Hospitals

Healthcare workers (HCWs) stand at the frontline for fighting coronavirus disease 2019 (COVID-19) pandemic. This puts them at higher risk of acquiring the infection than other individuals in the community. Defining immunity status among health care workers is therefore of interest since it helps to mitigate the exposure risk. This study was conducted between May 20th and 30th, 2020. Eighty-five hospitals across Kingdom of Saudi Arabia were divided into 2 groups: COVID-19 referral hospitals are those to which RT-PCR-confirmed COVID-19 patients were admitted or referred for management (Case-hospitals). COVID-19 nonaffected hospitals where no COVID-19 patients had been admitted or managed and no HCW outbreak (Control hospitals). Next, seroprevalence of severe acute respiratory syndrome coronavirus 2 among HCWs was evaluated; there were 12,621 HCWs from the 85 hospitals. There were 61 case-hospitals with 9379 (74.3%) observations, and 24 control-hospitals with 3242 (25.7%) observations. The overall positivity rate by the immunoassay was 299 (2.36%) with a significant difference between the case-hospital (2.9%) and the control-group (0.8%) (P value <0.001). There was a wide variation in the positivity rate between regions and/or cities in Saudi Arabia, ranging from 0% to 6.31%. Of the serology positive samples, 100 samples were further tested using the SAS2pp neutralization assay; 92 (92%) samples showed neutralization activity. The seropositivity rate in Kingdom of Saudi Arabia is low and varies across different regions with higher positivity in case-hospitals than control-hospitals. The lack of neutralizing antibodies (NAb) in 8% of the tested samples could mean that assay is a more sensitive assay or that neutralization assay has a lower detection limits; or possibly that some samples had cross-reaction to spike protein of other coronaviruses in the assay, but these were not specific to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

Immunologic Hyporesponsiveness to Serogroup C but Not Serogroup A following Repeated Meningococcal A/C Polysaccharide Vaccination in Saudi Arabia

In Saudi Arabia, vaccination with the meningococcal A/C polysaccharide (MACP) vaccine is advised every 3 years. A clinical outcome study was performed to test the effect of repeat vaccination with the MACP vaccine on the immune responses among Saudi nationals who live in the Makkah and Jeddah areas. Subjects (n = 230) aged 10 to 29 years were selected: 113 subjects with two or more prior vaccinations with the MACP vaccine, 79 subjects with one prior vaccination with the MACP vaccine, and 38 subjects naïve to vaccination with the MACP vaccine. All subjects received the MACP vaccine in 2002, and serum bactericidal antibody (SBA) titers were measured before and 1 month after vaccination with the MACP vaccine. For serogroup C, geometric mean SBA titers 1 month following vaccination with the MACP vaccine were 708.6 (95% confidence interval [CI], 217.5 to 2,308.9) for those naïve to prior vaccination with the MACP vaccine, and they were significantly higher (P < 0.0001) than 25.0 (95% CI, 12.4 to 50.2) for those who had received one prior vaccination with the MACP vaccine and 32.4 (95% CI, 18.7 to 56.4) for those who had received two or more doses of the MACP vaccine. For serogroup A, the geometric mean SBA titer 1 month after receipt of the MACP vaccine was 1,649.3 (95% CI, 835.2 to 3,256.9) for those naïve to prior vaccination, and the titers were lower (P = 0.67) than 2,185.7 (95% CI, 1,489.4 to 3,207.7) for those who had received one prior dose of the MACP vaccine and significantly lower (P = 0.042) than 3,540.8 (95% CI, 2,705.2 to 4,634.5) for those who had received two or more doses of the MACP vaccine. For serogroup C, the proportions of nonresponders (SBA titers, <8) were 19% for the naïve cohort, 52% for the cohort with one prior vaccination, and 49% for the cohort with two or more prior vaccinations. Following repeated doses of the MACP vaccine, hyporesponsiveness to serogroup C is evident, with high percentages of MACP vaccinees having SBA titers below the putative protective SBA titer. Serogroup A responses following vaccination with the MACP vaccine were boosted. Introduction of the serogroup C conjugate vaccine would provide long-term protection against serogroup C disease; however, quadrivalent conjugate vaccines are required to provide long-time protection against disease caused by serogroups A, W135, and Y

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

Launching COVID-19 vaccination in Saudi Arabia: Lessons learned, and the way forward

This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.The Severe Acute Respiratory Syndrome Coronavirus 2 (SARSCoV- 2) emerged in Wuhan City, China. The SARS-CoV-2 crossed borders and quickly transformed into a "Public health emergency of international concern". Countries around the globe are in the race to achieve herd immunity. We describe the steps taken by Saudi Arabia to achieve this goal

Clinical features and outcome of human Mpox (Monkeypox) in Saudi Arabia: An observational study of travel-related cases

Background: The 2022 Monkeypox virus (Mpox) outbreak had involved multiple countries around the globe. Here, we report clinical features and outcome of human Mpox of the first cases in Saudi Arabia. Methods: We obtained records of confirmed Mpox cases in Saudi Arabia from the public electronic health information system, Health Electronic Surveillance Network (HESN) and the healthcare providers completed a de-identified structured clinical data collection form. Results: The reported seven cases were travel-related and all were males between 24 and 41 years of age (mean age + SD) was 30.14 (+ 6.69) years. Of the cases, three (43 %) had heterosexual contact and the others had other intimate encounters while traveling abroad. They presented with skin lesions (100 %), fever (86 %), and lymphadenopathy (71 %). The illness was mild to moderate, did not require antiviral medications, and lasted 7–15 days. The mean duration of skin rash (+ SD) was 10 (+ 2.68) days. Routine laboratory tests (CBC, BUN, serum electrolytes, and liver enzymes) were within normal limits, and initial screening for HIV was negative. Expanded contact tracing did not reveal secondary cases of Mpox in the community or the healthcare setting. Conclusion: The current study showed heterosexual transmission of Mpox and the clinical course was mild and non-complicated. Therefore, clinicians and public health professionals should consider Mpox among individuals presenting with skin rash especially in the context of the investigation of HIV and other sexually transmitted diseases