Popular science: why Omi Keron strain "needs attention"

  Xinhua News Agency, London, November 27 (Reporter Guo Shuang) The World Health Organization urgently convened a special evaluation meeting on the 26th of the new coronavirus mutant Omi Kiron strain that has recently appeared in some countries and listed it as a "need to pay attention". Variant strains require countries to strengthen monitoring and sequencing.

  Why does the Omi Keron strain "need attention"?

What is the significance of this virus mutation?

Are the existing anti-epidemic tools still effective?

Variation is worth paying attention to

  All viruses, including the new coronavirus, may make "mistakes" in the process of self-replication, which is what people often call mutations.

Most of the mutations will not make the virus "discretionary", but there are also some mutations that will cause the virus to change the traits that are worthy of attention.

  According to Thomas Peacock, an expert in virology at Imperial College London, the newly discovered Omi Kiron strain in November has undergone many mutations. There are 32 mutations in its surface spike protein alone, and the new coronavirus is exactly Infects the human body through the binding of spike protein to human cell receptors.

This new strain "seems to have mutations at all recognized antigenic sites", which may affect the recognition of spike proteins by most antibodies.

  Lawrence Young, a virologist at the University of Warwick in the United Kingdom, said that the new strain not only combines some of the mutations in other strains into one for the first time, but also new mutations.

  The World Health Organization held an emergency evaluation meeting on the 26th. It considered some mutations in the Omi Keron strain to be "worrying" and listed it as a mutant strain that "needs attention", requesting countries to strengthen monitoring and sequencing.

The significance of the mutation is still unknown

  The WHO introduced on the 26th that this new strain was confirmed for the first time in South Africa on the 9th and was reported to the WHO for the first time on the 24th.

From an epidemiological point of view, the infection rate of the new coronavirus in South Africa has risen sharply in recent weeks, which is consistent with the detection of the Omi Keron strain.

  Preliminary evidence shows that the Omi Keron strain is detected faster than other mutant strains that have caused a surge in infections in the past, indicating that this latest mutant strain may have a growth advantage.

In addition, compared with other mutant strains that "need attention" before, the Omi Keron strain may increase the risk of people being infected with the new crown a second time.

  However, researchers do not yet know how dangerous the Omi Keron strain is.

The beta strain, which is also a variant strain that needs attention, surprised researchers when it first appeared, but it was eventually proved to be less dangerous and was gradually replaced by the delta strain.

  Sharon Peacock, who leads the new coronavirus gene sequencing project at the University of Cambridge in the United Kingdom, said that existing data show that new strains carry mutations that may increase infectivity, but the significance of many mutations is still unknown.

  Peter Oppenshaw, professor of experimental medicine at Imperial College, pointed out that although the Omi Keron strain may spread faster, the recent surge in the number of infections in South Africa may also be related to intensive surveillance. Will the new strain replace the Delta strain in South Africa It is difficult to say that it has become a major epidemic strain.

Epidemic prevention tools are still effective

  Will the Omi Kiron strain invalidate existing diagnosis and treatment methods and vaccines?

According to WHO, the current commonly used polymerase chain reaction test (nucleic acid test) can still be used to label Omi Keron strain.

  In terms of vaccine effectiveness, Neil Ferguson, an infectious disease expert at Imperial College London, said that there is no reliable assessment of the Omi Kiron strain that may weaken the vaccine's effectiveness, so it is too early to assess its risk.

Oppenshaw believes that in the face of new strains, the current vaccine is "very unlikely" to be completely ineffective, but more data is still needed to determine the protective efficacy of the vaccine.

  Richard Hatchett, CEO of the Epidemic Prevention Innovation Alliance, pointed out that the emergence of new strains makes it more urgent to develop a more effective new crown vaccine. In addition, it is necessary to continue to expand vaccination globally to reduce the spread of the virus. .

  Some experts said that although it is not clear how much the Omi Kiron strain poses to public health, the potential consequences of not taking action may be serious.

Unlike the Delta strain, the Omi Kiron strain has received widespread global attention when it first appeared, which may help people take measures earlier to curb the spread of the epidemic.

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