Monday, 6 December 2021

COVID-19: What do we know about the C.1.2 variant?

  • Researchers have identified a new SARS-CoV-2 variant, which they refer to as C.1.2.
  • C.1.2 contains mutations associated with increased transmissibility and ability to evade antibodies than other variants.
  • However, experts say the public should not panic about the C.1.2 variant.
  • They add that public health protocols, such as vaccinations, wearing a mask, and social distancing, are effective ways to prevent infection.

The more viruses spread, the more likely they are to mutate and form different variants. Variants that become more transmissible, resistant to current treatment options and vaccines, or cause more severe disease, are called Variants of Concern (VOC).

The World Health Organization (WHO)Trusted Source currently recognizes four SARS-CoV-2 VOCs:

  • Alpha B.1.1.7, first detected in September 2020 in the United Kingdom
  • Beta B.1.351, first detected in May 2020 in South Africa
  • Gamma P.1, first detected in November 2020 in Brazil
  • Delta B.1.617.2, first detected in October 2020 in India

Viruses need a host to replicate and mutate. The only way to stop new and more dangerous variants of SARS-CoV-2 from emerging is to prevent transmission and infection.

SARS-CoV-2 replicates quicker in unvaccinated people and, therefore, the virus has more opportunity to mutate. As these individuals have not already developed an immune response to the virus, it can survive and multiply for longer periods of time in their bodies.

The more opportunity SARS-CoV-2 has to cause infection in unvaccinated individuals, the higher the chance for new VOCs to emerge.

In recent research, scientists from the National Institute for Communicable Diseases (NICD) in Johannesburg, South Africa, alongside other institutions in the country, identified and discussed a new potential Variant of Interest called C.1.2.

Since its initial discovery in May 2021, scientists have detected the C.1.2 variant in seven other countries, including New Zealand, the U.K., and China. While it has some characteristics that may cause concern, experts are still gathering data.

A recent study investigating the variant appears on the preprint server, medRxiv.

Using genetic analysis, the study authors note that C.1.2 contains many mutations also present in the Alpha, Beta, Delta, and Gamma variants of SARS-CoV-2. The researchers state these mutations make it easier for the virus to enter target cells, resist current treatments and vaccines, and pass from one person to another.

“​​Scientists are concerned about the variant, because of how quickly it has mutated: it is between 44 and 59 mutations away from the original virus detected in Wuhan, [China] making it more mutated than any other WHO-identified VOC or Variant of Interest,” said Dr. Vinod Balasubramaniam, senior lecturer at Monash University of Malaysia, who was not involved in the study.

“It also contains many mutations that have been associated with increased transmissibility and a heightened ability to evade antibodies in other variants,” the scientists said, “though they occur in different mixes, and their impacts on the virus are not yet fully known,” he added.

As the variant has had just a few months to circulate, knowledge on how it works is limited. However, the researchers reported that cases of the variant have increased in recent months at a similar rate to the Beta and currently dominant Delta variants as they began to spread in South Africa.

In May, C.1.2 accounted for 0.2% of genomes sequenced, in June, 1.6%, and in July, 2.0%.

The researchers also note there is usually a delay of 2–4 weeks between sampling and data being publicly available. This, alongside limitations in their sampling capacity, may mean the variant is more common than current data suggests.

“Viruses mutate in part as a result of an immune attack,” Dr. Cathrine Scheepers, first author of the study and senior medical scientist at the NICD in South Africa, told Medical News Today, “When someone [acquires an infection] with a virus, our antibodies bind onto this virus to kill it and prevent it from getting into our cells.

“During infection, the virus will mutate randomly. If these random mutations confer a benefit, such as the ability to evade these immune attacks by preventing antibody binding, that mutation will increase in number, as viruses with that mutation have a competitive advantage,” she continued.

“The longer somebody [has an infection] with a particular virus, the more chance it has to accumulate a lot of mutations. Since this lineage (C.1.2) is so highly mutated, we hypothesize it is a result of a prolonged infection allowing the virus to accumulate many mutations before being transmitted to others,” she added.

Source: Medical News Today

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