The Epidemiology of Hundreds of Individuals Infected with Omicron BA.1 in Middle-Eastern Jordan

In less than two months of its detection in Jordan, lineage B.1.1.529 recognized as Omicron, is constituting 55% of all confirmed coronavirus disease of 2019 (COVID-19) infections causing a rise in the daily cases in the country. Herein, we report on 500 cases, among the first identified Omicron infections in Jordan. We also report on the genomic diversity of 25 Omicron viruses identified in nasopharyngeal swabs from Jordan. Our results indicated that 96% of study participants were vaccinated who had asymptomatic, mild or moderate disease. One unvaccinated individual developed severe disease. The median age of Omicron cases was 30 years, and most frequent disease symptoms were: fever, coughing, sore throat, runny nose, general fatigue and muscle/joint pain. Viral genomic analysis results revealed that the BA.1 is the dominant Omicron sublineage in Jordan, with 45 to 58 total mutations. We identified a few amino acid modifications that could impact the accuracy of some polymerase chain reaction (PCR) tests. In summary, infections caused by BA.1 seem milder than earlier infections. However, it is unknown whether this change is due to alterations in the immunity landscape of the infected population or is the result of viral genetic mutations that reduced viral virulence. Hence, comparing similar studies from different countries is likely to give us a get a better understanding of this variant, its behavior and the impact on disease characteristics.