The new outbreak of the COVID-Omicron strain “KP.3.1.1” is the main strain in the United States: PPTVHD36

Faculty of Medicine Medical Genome Center Ramathibodi Hospital also posted on Facebook. Center for Medical Genomics New omicron strain KP.3.1.1 becomes dominant strain in United States The estimated number of daily infections in the United States now tops 900,000, with the KP.3.1.1 strain close to becoming dominant weight This figure represents an increase of 59% compared to the 12 month average, with around 1 in 37 people currently infected.

Infectious cases of COVID-19, 560 this week, lowest in 8 months.

Jesus reports that “Omicron BA.2.X” in South Africa has changed in more than 100 roles.

This rapid increase reflects the increased transmission of the strain. and the importance of maintaining public health measures.

Spreading and becoming a dominant species

The KP.3.1.1 strain of COVID-19 has emerged as the largest strain in the United States, accounting for 27.8% of detected infections. According to the latest estimates from the Centers for Disease Control and Prevention (CDC), this strain, a subtype of KP.3, has rapidly risen to prominence. Crossing other strains such as LB.1 (16%), which is third after KP.3 (20.1%) In Thailand, random genetic decoding of the whole genome found 8 cases of KP. 3 omicrons and LB.1 Total 2 cases, KP.3.1.1 still not found.

special mutation

Omicron KP.3.1.1 has several key mutations that lead to a better ability to spread infections and evade immunity. in particular It has the Q493E mutation, which was also found in the previous strain, Omicron KP.3 These mutations occur near the receptor binding region (RBM) of the virus spike protein. This affects the ability of the virus to bind better to the ACE2 receptor on the cell surface and avoid antiviral antibodies.

** Q493E is a mutation that occurs in the spike protein of the SARS-CoV-2 virus by:

• Q is the amino acid glutamine (Glutamine).
• E is the amino acid glutamic acid (Glutamic acid).
• The amino acid position in the mutated protein sequence is 493 (Q->E).

S31- refers to the absence of an amino acid in position 31 of the spike protein, where:

• S is the amino acid sequence (Serine)
• Position 31 is the missing amino acid in the protein chain.
• Indicator – indicates the absence of amino acids.

Avoidance of immunity and increased chance of re-infection

Original omicron sequences have a very high ability to evade immunity. This makes it difficult for the immune system to intervene. Compared to current population immunity After we have been infected with COVID-19 or received the vaccine The body will build immunity to prevent relapse In the first 6 months , our immunity will be very strong. Disease can be prevented up to more than 90%, meaning that the chance of relapse at this time is less than 10%.

However, after 6 months, immunity gradually decreases over time, but on average, We still have protective immunity for about 18 months, which is the average time between infections.

Possible to return

If a person has been infected with omicron KP.3 before, it is technically possible to be re-infected with the KP.3.1.1 strain, although there may be some short-term protection available time. But the high ability of the KP.3.1.1 strain to evade immunity means that reinfection can occur. Especially when immunity goes down over time.

Avoidance of KP family immunity

The KP family of omicrons, including KP.3 and KP.3.1.1, are thought to be the ones with the highest ability to evade immunity from a COVID-19 outbreak shortly after to recover from infection with the original strain Although some protection may last for about 6 weeks, the high transmission rate and immune evasion of these strains indicate the need for caution. This is especially true during heavy breakouts.

Vaccine effectiveness

Current vaccines targeting the XBB.1.5 strain of COVID-19 help prevent severe illness in high-risk groups. But they are less effective in protecting against infection from newer strains, including KP.3.1.1 vaccines due to the drop targeting omicron strains KP.2 and JN .1 more effective against KP.3.1.1 due to similar sequences.

In summary, although the omicron strain KP.3.1.1 was less able to evade immunity than the original omicron strain compared to the immunity of the current population, But there is still a high risk of re-infection and rapid distribution. We should continue to follow vaccination recommendations and public health guidelines. To reduce the impact of these highly infectious omicron strains.