tetano
Editor, Senior Moderator
J Infect Public Health
. 2021 Apr 24;14(7):832-838.
doi: 10.1016/j.jiph.2021.04.006. Online ahead of print.
Nationwide Seroprevalence of SARS-CoV-2 in Saudi Arabia
Naif Khalaf Alharbi[SUP] 1 [/SUP], Suliman Alghnam[SUP] 2 [/SUP], Abdullah Algaissi[SUP] 3 [/SUP], Hind Albalawi[SUP] 4 [/SUP], Mohammed W Alenazi[SUP] 4 [/SUP], Areeb M Albargawi[SUP] 4 [/SUP], Abdullah G Alharbi[SUP] 5 [/SUP], Abdulaziz Alhazmi[SUP] 6 [/SUP], Ali Al Qarni[SUP] 7 [/SUP], Ali Alfarhan[SUP] 8 [/SUP], Hosam M Zowawi[SUP] 9 [/SUP], Hind Alhatmi[SUP] 8 [/SUP], Jahad Alghamdi[SUP] 2 [/SUP], Fayhan Alroqi[SUP] 10 [/SUP], Khalid Batarfi[SUP] 8 [/SUP], Yaseen M Arabi[SUP] 10 [/SUP], Anwar M Hashem[SUP] 11 [/SUP], Mohammed Bosaeed[SUP] 10 [/SUP], Omar Aldibasi[SUP] 2 [/SUP]
Affiliations
Abstract
Background: Estimated seroprevalence of Coronavirus Infectious Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) is a critical evidence for a better evaluation of the virus spread and monitoring the progress of COVID-19 pandemic in a population. In the Kingdom of Saudi Arabia (KSA), SARS-CoV-2 seroprevalence has been reported in specific regions, but an extensive nationwide study has not been reported. Here, we report a nationwide study to determine the prevalence of SARS-CoV-2 in the population of KSA during the pandemic, using serum samples from healthy blood donors, non-COVID patients and healthcare workers (HCWs) in six different regions of the kingdom, with addition samples from COVID-19 patients.
Methods: A total of 11,703 serum samples were collected from different regions of the KSA including; 5395 samples from residual healthy blood donors (D); 5877 samples from non-COVID patients collected through residual sera at clinical biochemistry labs from non-COVID patients (P); and 400 samples from consented HCWs. To determine the seroprevalence of SARS-CoV-2, all serum samples, in addition to positive control sera from RT-PCR confirmed COVID-19 patients, were subjected to in-house ELISA with a sample pooling strategy, which was further validated by testing individual samples that make up some of the pools, with a statistical estimation method to report seroprevalence estimates.
Results: Overall (combining D and P groups) seroprevalence estimate was around 11% in Saudi Arabia; and was 5.1% (Riyadh), 1.5% (Jazan), 18.4% (Qassim), 20.8% (Hail), 14.7% (ER; Alahsa), and 18.8% in Makkah. Makkah samples were only D group and had a rate of 24.4% and 12.8% in the cities of Makkah and Jeddah, respectively. The seroprevalence in Saudi Arabia across the sampled areas would be 12 times the reported COVID-19 infection rate. Among HCWs, 7.5% (4.95-10.16 CI 95%) had reactive antibodies to SARS-CoV-2 without reporting any previously confirmed infection. This was higher in HCWs with hypertension. The study also presents the demographics and prevalence of co-morbidities in HCWs and subset of non-COVID-19 population.
Interpretation: Our study estimates the overall national serological prevalence of COVID-19 in Saudi Arabia to be 11%, with an apparent disparity between regions. This indicates the prevalence of asymptomatic or mild unreported COVID-19 cases.
Keywords: Antibody; COVID-19; SARS-CoV-2; Saudi Arabia; Seroprevalence.
. 2021 Apr 24;14(7):832-838.
doi: 10.1016/j.jiph.2021.04.006. Online ahead of print.
Nationwide Seroprevalence of SARS-CoV-2 in Saudi Arabia
Naif Khalaf Alharbi[SUP] 1 [/SUP], Suliman Alghnam[SUP] 2 [/SUP], Abdullah Algaissi[SUP] 3 [/SUP], Hind Albalawi[SUP] 4 [/SUP], Mohammed W Alenazi[SUP] 4 [/SUP], Areeb M Albargawi[SUP] 4 [/SUP], Abdullah G Alharbi[SUP] 5 [/SUP], Abdulaziz Alhazmi[SUP] 6 [/SUP], Ali Al Qarni[SUP] 7 [/SUP], Ali Alfarhan[SUP] 8 [/SUP], Hosam M Zowawi[SUP] 9 [/SUP], Hind Alhatmi[SUP] 8 [/SUP], Jahad Alghamdi[SUP] 2 [/SUP], Fayhan Alroqi[SUP] 10 [/SUP], Khalid Batarfi[SUP] 8 [/SUP], Yaseen M Arabi[SUP] 10 [/SUP], Anwar M Hashem[SUP] 11 [/SUP], Mohammed Bosaeed[SUP] 10 [/SUP], Omar Aldibasi[SUP] 2 [/SUP]
Affiliations
- PMID: 34118732
- DOI: 10.1016/j.jiph.2021.04.006
Abstract
Background: Estimated seroprevalence of Coronavirus Infectious Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) is a critical evidence for a better evaluation of the virus spread and monitoring the progress of COVID-19 pandemic in a population. In the Kingdom of Saudi Arabia (KSA), SARS-CoV-2 seroprevalence has been reported in specific regions, but an extensive nationwide study has not been reported. Here, we report a nationwide study to determine the prevalence of SARS-CoV-2 in the population of KSA during the pandemic, using serum samples from healthy blood donors, non-COVID patients and healthcare workers (HCWs) in six different regions of the kingdom, with addition samples from COVID-19 patients.
Methods: A total of 11,703 serum samples were collected from different regions of the KSA including; 5395 samples from residual healthy blood donors (D); 5877 samples from non-COVID patients collected through residual sera at clinical biochemistry labs from non-COVID patients (P); and 400 samples from consented HCWs. To determine the seroprevalence of SARS-CoV-2, all serum samples, in addition to positive control sera from RT-PCR confirmed COVID-19 patients, were subjected to in-house ELISA with a sample pooling strategy, which was further validated by testing individual samples that make up some of the pools, with a statistical estimation method to report seroprevalence estimates.
Results: Overall (combining D and P groups) seroprevalence estimate was around 11% in Saudi Arabia; and was 5.1% (Riyadh), 1.5% (Jazan), 18.4% (Qassim), 20.8% (Hail), 14.7% (ER; Alahsa), and 18.8% in Makkah. Makkah samples were only D group and had a rate of 24.4% and 12.8% in the cities of Makkah and Jeddah, respectively. The seroprevalence in Saudi Arabia across the sampled areas would be 12 times the reported COVID-19 infection rate. Among HCWs, 7.5% (4.95-10.16 CI 95%) had reactive antibodies to SARS-CoV-2 without reporting any previously confirmed infection. This was higher in HCWs with hypertension. The study also presents the demographics and prevalence of co-morbidities in HCWs and subset of non-COVID-19 population.
Interpretation: Our study estimates the overall national serological prevalence of COVID-19 in Saudi Arabia to be 11%, with an apparent disparity between regions. This indicates the prevalence of asymptomatic or mild unreported COVID-19 cases.
Keywords: Antibody; COVID-19; SARS-CoV-2; Saudi Arabia; Seroprevalence.