The Omicron variant is a variant of SARS-CoV-2, the virus that causes Covid-19. As reported to the WHO from South Africa on 24 November 2021, it is the newest variant as of December 2021. The WHO has designated it as a variant of concern. Compared to previous variants of concern, Omicron is believed to be far more contagious, and spreads around 70 times faster than any previous variants in the bronchi.
Scientists don’t know what makes Omicron so communicable yet, but a few clues have emerged from preliminary research. A team of British scientists found that Omicron is particularly good at infecting cells in the nose, so people can release new virus particles when they breathe out through their noses. It is also proficient at dodging antibodies produced by vaccines and previous infections.
Omicron has more or less the same symptoms as the earlier variants. According to Dr Otto O. Yang, an infectious disease physician at the University of California, there’s probably a huge amount of overlap between Omicron and the prior variants, and their differences are fairly subtle. Thus, it’s likely that the symptoms of Omicron resemble Delta’s more than they differ. One possible difference in their symptoms is that Omicron may be less likely than earlier variants to cause a loss of taste and smell.
As stated earlier, Omicron can evade antibodies produced by vaccines and start multiplying in the nose and throat. Along with triggering the production of antibodies, vaccines also stimulate the growth of T cells that help fight a particular disease. Preliminary studies suggest that Omicron infections cannot get past the T-cell line of defense, which makes it harder for Omicron to reach deep into the airway. This is how vaccines reduce the severity of Covid.
Several studies indicate that full vaccination, plus a booster shot, provides strong protection against Omicron infection. Without a booster, however, two doses of a vaccine like Pfizer-BioNTech’s or Moderna’s provide much less protection. Nonetheless, vaccines reduce the severity of Covid. The risk of being admitted to a hospital was lower by 65% for those who had received two doses of a vaccine.
Scientists measure the severity of a coronavirus variant by examining how many infected people end up in the hospital. A British study found that the risk of hospitalization due to Omicron is half that of Delta. By now, the majority of people in the world possess antibodies, either from vaccines or from previous infections. Their heightened immunity lowers their chances of ending up in a hospital, so it’s important to get vaccinated, preferably followed by a booster to minimize the risk of Omicron.