Is there a replacement for the global epidemic leader? Scholars analyze the reasons for the rise of "XBB.1.5": Even vaccines are useless against it
Is there a replacement for the global epidemic leader? “XBB.1.5” has doubled the number of cases in the United States in just 4 weeks
Is the virus that dominates the global epidemic about to change hands? For weeks, scientists have continued to observe the dominance of Omicron variants around the world, with the subvariant BQ (BQ.1, BQ.1.1) thought to be excluding all other variants and seemingly taking the lead. However, on December 30 last year (2022), data released by the U.S. Centers for Disease Control and Prevention (CDC) showed that the “XBB.1.5” virus emerged as a dark horse, taking advantage of immune escape to cause Another epidemic wave.
The US CDC estimates that XBB.1.5 has more than doubled its share of total new coronavirus cases in the past four weeks, with new infection cases rising from 4% to 41% in December. The CDC estimates that XBB.1.5 may cause 75% of the increase in new cases in the northeastern United States. According to the World Health Organization, XBB has been discovered in at least 70 countries/regions, and was rampant in India, Singapore and other places in October, with the number of infections trending to surge.
Immune escape ability “best in history”! Scholars reveal: Neutralizing antibodies are “63 times” less likely
Dr. David Ho, professor of microbiology and immunology at Columbia University, recently worked with his research team on the immune response of infected people, people vaccinated with the new coronavirus vaccine, and people vaccinated with the bivalent vaccine after being infected with XBB, XBB.1, BQ.1, and BQ 1.1 Why. The results show that XBB.1 has the highest probability of “immune escape”. The probability of antibody neutralization in infected and vaccinated persons is 63 times lower than that of BA.2 and 49 times lower than that of BA.4 and BA.5.
Even though XBB’s immune evasion ability is beyond scientists’ imagination, Dr. Rick Bright, an American immunologist and former director of the Biomedical Advanced Research and Development Authority, believes that Singapore’s experience with XBB is worth learning from other countries around the world. He believes that although the number of cases in Singapore has surged, the number of hospitalizations and deaths has remained stable. The potential reason may be that Singapore’s high vaccination rate of the bivalent vaccine has played a key role.
Even the new coronavirus vaccine has no effect on it? “4 features” make XBB take the world by storm
Michael Osterholm, an infectious disease scholar at the University of Minnesota in the United States, believes that based on the current research data, the protective effect of the non-bivalent COVID-19 vaccine on XBB is low; the latest research in “Cell Press” also pointed out that even if the patient has been diagnosed For new coronaviruses, such as BA.4, BA.5, etc., neutralizing antibodies are “almost inactive” against XBB, showing their ability to escape immunity and are indeed more troublesome than other sub-variants.
Even so, Osterholm still emphasized that the bivalent vaccine still provides a certain degree of protection and has a significant impact on whether an individual will become seriously ill or die due to infection with the virus. Osterholm said that the latest data shows that the risk of death among people vaccinated with bivalent vaccines is three times lower than those who have not been vaccinated.
Osterholm said that current clinical trials show that although antibody treatment has very limited effectiveness against XBB 1.5, other antiviral drugs such as Paxlovid and Remdesivir should still have certain effectiveness. In addition, past epidemic prevention measures, such as rapid screening, wearing masks, indoor air ventilation or maintaining social distance, still have the effect of preventing the spread of the virus. Even as the virus continues to evolve, people can still take the initiative to protect themselves from COVID-19.
Will the epidemic get out of control during the Chinese New Year and China’s lifting of lockdown? Intensivist reminds: Do 5 things before going home
Dr. Huang Xuan, an expert in critical care medicine, also stated in the community that the changes in confirmed cases in the past week can be found that the proportion of BA.5 has dropped from 82% to 62%; while the proportion of mutant strains such as BQ.1 and XBB has increased. Dr. Huang Xuan pointed out that the XBB.1.5 virus has a higher “ACE2” binding affinity, which not only locks onto human cells better, but also has “stickier” properties. Calculating its exponential growth rate, it is faster than any previous virus. . Coupled with the increase in people returning to their hometowns during the New Year, it is not impossible that the opportunities for “family transmission” will increase dramatically.
As for how to prevent the XBB virus so that you and your family can celebrate the New Year with peace of mind? Dr. Huang Xuan explained that there are 5 things that people must pay more attention to:
1. Quickly screen before going home.
Regardless of whether you have contact with immigrants, as long as you have been in crowded places or high-risk places, you may be at risk of contracting the new coronavirus. People who work in these high-risk places must develop the habit of regular screening to confirm whether they are infected with the epidemic in a timely manner.
Therefore, protecting your own health and avoiding family transmission when you go home for the New Year is the only way to protect the health of your family. Dr. Huang Xuan suggested that a quick screening should be done 48 hours before the Chinese New Year to confirm the negative result before going home for the Chinese New Year.
2. Avoid being a spreader of ignorance.
Most of the current COVID-19 infections are mild or completely asymptomatic. Some people even have symptoms and think they are caused by a cold, but their physical strength has not weakened. Dr. Huang Xuan warned that these asymptomatic and mildly infected people may have become “super spreaders” without knowing it.
Therefore, before any large gathering or dinner, if you feel unwell, you should not reluctantly attend. You should first clarify whether you have been diagnosed and rest at home in order to recover as soon as possible and avoid the continued expansion of the invisible transmission chain.
3. Take medication in advance.
If people test positive after rapid screening and are in a high-risk group, they should seek medical treatment immediately and use antiviral drugs for treatment. Previous studies have pointed out that timely use of the antiviral drug “Paxlovid” in the early stages of diagnosis and symptoms can help reduce mortality in high-risk groups. Therefore, if you have chronic diseases or cardiovascular diseases before, timely treatment with antiviral drugs can save your life.
4. Administer bivalent vaccine.
Dr. Huang Xuan explained that to prevent the Lunar New Year infection wave, we still need to get a complete vaccine and increase the body’s protection. It is best to get vaccinated in the near future, because the time when the vaccine will have the best effect 2 weeks after administration happens to be the Lunar New Year, so it can exert a good protective effect.
“Those who have elderly people or high-risk groups at home, those who have not yet received the additional dose, and those who have been diagnosed with infection and have recovered for more than 3 months are the groups who can consider the bivalent vaccine!”
5. Wear a mask when entering indoors.
Dr. Huang Xuan emphasized that not only the new coronavirus is currently raging, but the influenza virus and RSV virus can also cause “droplet transmission” through the air. Therefore, masks should be worn in crowded outdoor places (such as New Year shopping streets, Lantern Festival lantern riddle guessing activities, etc.), and masks should be worn when leaving indoor restaurants to prevent viruses from invading the body.
In general, Dr. Huang Xuan reminds the public that the epidemic situation in Taiwan has begun to increase again recently, and it coincides with the Lunar New Year eve when there are huge crowds. Measures such as “quick screening + quick vaccination + quick wearing” can be said to be useless. few. If you have relatives and friends coming back from abroad for a reunion during the Lunar New Year, because epidemic prevention abroad may not be as strict as Taiwan, you can also get vaccinated with next-generation vaccines in advance to increase your own protection.
Source:
TAG-VE statement on Omicron sublineages BQ.1 and XBB
Omicron offshoot XBB.1.5 could drive new Covid-19 surge in US
Alarming antibody evasion properties of rising SARSCoV-2 BQ and XBB subvariants
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