Clinical and Serological Findings of COVID-19 Participants in the Region of Makkah, Saudi Arabia

• Published in: Diagnostics (Basel) Vol. 12; no. 7; p. 1725
• Main Authors: Alzahrani, Othman R., Alanazi, Abdullah D., Kareinen, Lauri, Hawsawi, Yousef M., Alhadrami, Hani A., Khogeer, Asim A., Alatwi, Hanan E., Alharbi, Amnah A., Sironen, Tarja, Vapalahti, Olli, Hepojoki, Jussi, Zakham, Fathiah
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 15.07.2022; MDPI
• Subjects: Accuracy; Antibodies; Antigens; Coronaviruses; COVID-19; Disease transmission; ELISA; Enzymes; Hospitals; IgA; IgG ELISA; IgM; Infections; micro-neutralization assay; Middle East respiratory syndrome; Pilgrimages; Pilgrims; Proteins; Respiratory diseases; SARS-CoV-2; Serology; Severe acute respiratory syndrome coronavirus 2; Saudi Arabia; China; Saudi Arabia; IgA; SARS-CoV-2; Makkah; micro-neutralization assay; IgG ELISA; IgM; ELISA
• DOI: 10.3390/diagnostics12071725
• ISSN: 2075-4418

Makkah in Saudi Arabia hosts the largest annual religious event in the world. Despite the many strict rules enacted, including Hajj cancellation, city lockdowns, and social distancing, the region has the second highest number of new COVID-19 cases in Saudi Arabia. Public health interventions that identify, isolate, and manage new cases could slow the infection rate. While RT-PCR is the current gold standard in SARS-CoV-2 identification, it yields false positive and negative results, which mandates the use of complementary serological tests. Here, we report the utility of serological assays during the acute phase of individuals with moderate and severe clinical manifestations of SARS-CoV-2 (COVID19). Fifty participants with positive RT-PCR results for SARS-CoV-2 were enrolled in this study. Following RT-PCR diagnosis, serum samples from the same participants were analyzed using in-house ELISA (IgM, IgA, and IgG) and microneutralization test (MNT) for the presence of antibodies. Of the 50 individuals analyzed, 43 (86%) showed a neutralizing antibody titer of ≥20. Univariate analysis with neutralizing antibodies as a dependent variable and the degree of disease severity and underlying medical conditions as fixed factors revealed that patients with no previous history of non-communicable diseases and moderate clinical manifestation had the strongest neutralizing antibody response “Mean: 561.11”. Participants with severe symptoms and other underlying disorders, including deceased individuals, demonstrated the lowest neutralizing antibody response. Anti-spike protein antibody responses, as measured by ELISA, showed a statistically significant correlation with neutralizing antibodies. This reinforces the speculation that serological assays complement molecular testing for diagnostics; however, patients’ previous medical history (anamnesis) should be considered in interpreting serological results.