Isiaka Sanni Oluwasegun*

Department of Optometry and Vision Therapy, Makkah Specialist Eye Hospital Bauchi, Basar International Foundation, Nigeria

*Corresponding Author: Isiaka Sanni Oluwasegun, Department of Optometry and Vision Therapy, Makkah Specialist Eye Hospital Bauchi, Basar International Foundation, Nigeria.

Received: January 20, 2022; Published: March 07, 2022

Abstract

The purpose of this paper is to review recent studies on Delta and Omicron variants of SARS-CoV-2 as to their symptoms, disease presentation and diagnosis, how they are affecting us and how ocular exposure routes influence disease presentation. Delta and Omicron have similar symptoms that sufferers present with, but shortness of breath is peculiar to the Delta variant and sneezing is not a symptom of Delta but of the Omicron variant infection. PCR and Antigen tests are usually done to diagnose SARS-CoV-2 if the disease is suspected but genomic sequencing (an expensive diagnostic test) is required to diagnose the Delta, Omicron, or the exact SARS-CoV-2 variant. The Delta variant (B.1.617.2) had invaded over 163 nations as of August, 2021 after it was discovered in India in late 2020. The Omicron SARS‐CoV‐2 variant may be more transmissible but less severe than the Delta variant form. The Delta VOC mostly endangers those who are unvaccinated or just partially vaccinated but the Omicron variant may be associated with increased risk of reinfection. In South Africa, the base of the Omicron variant, children seem to have been affected more with increase in number of hospitalizations among those children under age 5. A few cases of Delta variant infections reported had ocular manifestation including red bloodshot eye and conjunctivitis, but there may be a connection between chronic yet SARS-CoV-2 (Omicron variant) and neuroparalytic keratitis. Further studies into the ocular manifestation of these two VOCs and the susceptibility of the ocular surface as a route of entry may revolutionize our understanding of the two VOCs.

Keywords: SARS-CoV-2; Delta Variant; Omicron Variant; Ocular Surface

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Citation

Citation: Isiaka Sanni Oluwasegun. “Delta and Omicron Variants".Acta Scientific Ophthalmology 5.4 (2022): 13-18.

Copyright

Copyright: © 2022 Isiaka Sanni Oluwasegun. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.