Delta strain ravages the U.S. epidemic prevention faces severe challenges
□ Our reporter's trainee reporter Wang Wei Our reporter's reporter Wu Qiong
The Delta strain has been marked by the WHO as one of the new coronavirus mutants that "need attention".
Recently, the number of infections with the delta mutant strain in the United States has continued to increase, and the number of newly confirmed cases in the United States every day is on the rise again.
As a large number of people travel, experts worry that it may cause the spread of the mutant virus to spread further, bringing new and serious challenges to the prevention and control of the US epidemic.
The number of cases has surged
According to reports, the delta mutant strain of the new coronavirus has appeared in all 50 states in the United States, and the number of new coronary pneumonia cases has begun to increase sharply in the southern and midwestern regions of the United States.
The epidemic situation in Florida is particularly severe. At present, 17% of the new cases in the United States are from the state.
WHO Director-General Tan Desai recently introduced the Delta strain in detail.
This strain was first discovered in India in October 2020 and was initially called a "double mutant" virus by the media.
This new mutant strain carries E484Q and L452R mutations, which may lead to immune escape and increased infectivity.
The WHO named it B.1.617 and named it with the Greek letter δ (delta) on May 31.
Tan Desai said that according to the data currently available, the delta strain is the most powerful new coronavirus variant found so far, and it spreads rapidly mainly in people who have not been vaccinated against the new crown.
Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in the United States, said that the delta strain follows the same pattern as the "alpha" mutant virus found in the UK.
He said, "Similar to the situation in the UK,'Delta' is currently the biggest threat to our efforts to get rid of the new crown epidemic."
Rochelle Valensky, director of the US Centers for Disease Control and Prevention, said that the delta strain can easily lead to "super transmission."
Viral gene sequencing revealed that nearly 50% of the sequenced viruses in some areas of the United States are Delta strains.
A study in Scotland also suggested that the delta strain may increase the risk of patients being admitted to the hospital.
However, the WHO believes that there is no indication that the Delta strain will cause the death rate of the new crown to rise.
According to the US Centers for Disease Control and Prevention, based on the distribution of the number of infections caused by several variant strains, the proportion of infections caused by the delta strain will reach 26.1% of the total number of new cases in the United States this week.
Low vaccination rate
At the same time, the US vaccination progress is showing signs of slowing down. The US has not achieved the goal of 70% of adults vaccinated with at least one dose of the new crown vaccine before Independence Day on July 4, as announced by President Biden.
Fauci said that in the past month, 99.2% of patients who died of the new coronavirus in the United States had not been vaccinated.
He added that in fact, many of the infected people can completely avoid the tragedy of death, and most of the people who are in desperation are because they have not been vaccinated.
A study by the US Centers for Disease Control and Prevention shows that the current vaccination rate among the 18 to 29-year-olds in the United States is low, and the 18- to 39-year-old group has the lowest willingness to vaccinate.
The latest public opinion survey jointly released by the ABC and the Washington Post shows that 30% of American adults said they have not been vaccinated against the new crown and will never be vaccinated.
In this group, 73% believe that US officials have exaggerated the risk of the delta mutant strain, and 79% believe that their risk of contracting the new coronavirus is small or no.
Jonathan Reiner, a professor of medicine at the University of Washington, said that states where the epidemic has rebounded have relatively low willingness to vaccinate against the new crown pneumonia. “In my hospital, there are already many young people infected with the new crown virus.”
William Schaffner, a professor in the Department of Infectious Diseases at Vanderbilt University Medical Center in the United States, said that people who have not been vaccinated against the new crown may become "mutant factories" of the virus.
Public health data show that areas with low vaccination rates are at high risk of being attacked by the Delta strain.
Take Mississippi as an example. Less than 30% of the people in the state are fully vaccinated, and of the newly confirmed cases and deaths in the past month, more than 90% are unvaccinated people.
American vaccine expert Paul Offit pointed out that if there are not enough people vaccinated, the number of people infected with the new crown virus in the United States may surge again this winter.
Call for the abandonment of differences
It is reported that in order to curb the spread of the delta strain, the federal government will dispatch a number of special teams to provide more professional guidance and anti-epidemic supplies to areas with high infection rates or high-risk areas.
The Public Health Agency of England issued a report in May that researchers analyzed the data between April 5 and May 16 and found that the second dose of the new crown vaccine jointly developed by Pfizer Pharmaceuticals Co., Ltd. and German Biotech Co., Ltd. was vaccinated for two weeks. Later, it can effectively prevent people from experiencing symptoms after being infected with the delta strain.
If you are vaccinated with the British AstraZeneca pharmaceutical company's vaccine, it will be effective to prevent symptoms after infection with the Delta strain.
The Centers for Disease Control and Prevention stated that the three vaccines currently approved for emergency use in the United States can provide protection against mutated virus infections including the Delta strain.
Fauci said that the United States has the tools to fight the virus, has enough vaccines, and has the ability to vaccinate all Americans.
Call on the people to abandon their differences, realize that the virus is the common enemy of mankind, and get vaccinated as soon as possible.
Maria Van Kelkhover, the technical leader of the WHO health emergency project, warned that although the vaccine is still effective against the current virus, there may be a series of mutations in the virus in the future, which will cause the vaccine to actually lose its effectiveness. People need to ensure the prevention of the situation.
Experts warn that after the mutated new coronavirus continues to replicate and infect more people, it will eventually form new variants.
People who have not been vaccinated provide an opportunity for the continuous replication of the mutant virus.
Schaffner said, “The more people who have not been vaccinated, the more opportunities for the new coronavirus to reproduce and evolve.” He pointed out that when the mutated virus evolves in the body of the infected person, it may mutate and may also cause it. More serious mutations.
Experts say that vaccinating the public as soon as possible is essential for the prevention and control of the epidemic.
The delta strain has become the main new coronavirus strain circulating in the United States.
If vaccination cannot be advanced quickly, a more dangerous mutant virus may evolve, leading to more cases of infection.