A Review on the Impact of the SARS-CoV-2 Omicron Subvariant on Elderly Patients with Diverse Co-Morbidities

The SARS-CoV-2 virus has caused a catastrophic impact on the world for the past 3 years. The virus has now returned with the emergence of the Omicron (B.1.1.529) variant. Within two months of its first emergence in South Africa, Omicron became the most dominating SARS-CoV-2 variant around the world, being the cause of the majority of new infections at present. Omicron has presented with the greatest transmission rate of all the previous variants despite the presence of mass vaccinations and acquired immunity. Several monoclonal antibodies and mRNA vaccines have failed to produce desired effects owing to a large number of mutations present in the Omicron variant. The introduction of the booster dose of the present mRNA vaccines has proven to be a great addition to the therapeutic armamentarium against the Omicron variant. Immunocompromised patients including the elderly, cancer patients, organ transplant recipients, and those with multiple comorbidities have been at a greater risk of developing severe diseases since the pre-Omicron era. The emergence of Omicron again raised a threat against this population. The protection from severe disease and mortality rates through the utilization of multiple immunizations and monoclonal antibodies has been controversial in this subgroup of patients. Thus, designing large-scale studies to evaluate the effectiveness of monoclonal antibodies and vaccines in these patients can provide evidence-based recommendations to improve survival in this population. This article attempts to discuss the different subvariants of Omicron, differences in the mutational aspects along with the particular focus on the consequences of the Omicron infection in the elderly population with diverse comorbidities.