Orthrus COVID-19 CH.1.1: The New Omicron Subvariant Posing New Threats

Orthrus COVID-19 CH.1.1 is a new subvariant of the Omicron variant of the SARS-CoV-2 virus that emerged in Southeast Asia in November 2022 and has since spread to other parts of the world, including Europe, the U.S., and China. It is named after a two-headed dog from Greek mythology that was killed by the hero Heracles. Orthrus COVID-19 has raised global concern because of its potential to be more transmissible and more resistant to vaccines than other omicron subvariants.

How does Orthrus COVID-19 CH.1.1 differ from other Omicron subvariants?

Orthrus COVID-19 belongs to the Omicron lineage CH.1.1, which is one of the four omicron descendent lineages that the World Health Organization (WHO) is currently prioritizing for tracking. It has a mutation called L452R, which was also seen in the highly contagious delta, BA.4, and BA.5 variants. This mutation is believed to increase the variant’s ability to bind to cellular receptors and evade neutralizing antibodies that were generated in response to vaccination or previous infection. It also has a mutation called P681R, which was also on the delta variant and is thought to make it better at attacking cells and causing more severe illnesses. In addition, Orthrus COVID-19 has another mutation called R346T, which may also help the strain fight off antibodies.

How prevalent is Orthrus COVID-19?

According to the latest estimates from the CDC, Orthrus COVID-19 accounted for around 1.5% of new COVID-19 cases in the U.S. region including Utah as of January 2023. However, Orthrus COVID-19 has a higher prevalence in other countries, such as the U.K. and New Zealand, where it accounts for about a quarter of cases. The WHO’s February 2023 COVID epidemiological update lists Orthrus COVID-19 among Europe’s top three most prevalent variants, clocking in at 12.3%, slightly behind BQ.1 at 13% and BQ.1.1 at 31.3%.

Are Vaccines Effective against Orthrus COVID-19?

There is limited data on the effectiveness of the current vaccines against Orthrus COVID-19. Still, some studies suggest that the variant may have a higher degree of vaccine escape than other omicron subvariants. A study by researchers from Ohio State University found that orthrus covid-19 and another new variant, CA.3.1, have a consistently stronger neutralization resistance than XBB, XBB.1, and XBB.1.5, which is astonishing and warrants continuous monitoring and further investigations. The study also found that our study highlights the continued waning of 3-dose mRNA booster efficacy against newly emerging omicron subvariants. Another study by the CDC found that currently authorized bivalent COVID-19 boosters demonstrated similar protection against symptomatic illness from the XBB/XBB.1.5 omicron subvariants as from BA.5-related subvariants.

Implications of Orthrus COVID-19 for public health

Orthrus COVID-19 poses a potential threat to public health because of its increased transmissibility and reduced vaccine efficacy, which could lead to another surge in cases, hospitalizations, and deaths. Kelly Oakeson, the chief scientist for next-generation sequencing and bioinformatics for the Utah Department of Health and Human Services, told the Deseret News that “we could be in for a wild ride if orthrus covid-19 is able to take hold.” He also said “we don’t want to see that again”, referring to the huge spike in cases that occurred with the original omicron variant last winter. Therefore, it is important to continue current vaccination strategies or investigate new ones, as well as maintain ongoing surveillance of emerging variants.

How can I protect myself and others from orthrus covid-19?

The best way to protect yourself and others from Orthrus COVID-19 is to follow the same preventive measures that apply to other variants of COVID-19. These include:

  • Getting vaccinated and boosted as soon as possible
  • Wearing a mask when indoors or in crowded settings
  • Practicing social distancing and avoiding large gatherings
  • Washing your hands frequently and using sanitizer
  • Staying home if you feel sick or have symptoms
  • Getting tested if you have been exposed or have symptoms
  • Following the guidance of local health authorities

By following these steps, you can help reduce the spread of orthrus covid-19 and other variants, and protect yourself and your community from the virus. It is important to stay vigilant and follow the preventive measures that can help protect yourself and others from the virus.


Orthrus COVID-19 CH.1.1 is a new subvariant of the Omicron variant that is more transmissible and better able to evade the immune protection provided by vaccines and prior infection. However, there are a number of things you can do to protect yourself from this subvariant, such as getting vaccinated and boosted, wearing a mask in public indoor settings, and washing your hands frequently. If you think you may have Orthrus COVID-19 CH.1.1, you should get tested and isolate yourself from others until you receive your results.

For more information and updates on orthrus covid-19 and other variants, visit WHO’s website.

Leave a Reply

Your email address will not be published. Required fields are marked *