The virus strain "Lambda" has appeared! It has spread to about 30 countries and regions

According to CNN, as the COVID-19 pandemic spreads, cases of infection with the "Lambda" strain have appeared in the United States. This variant strain was first discovered in Peru in August last year. Currently, 1,060 cases caused by the "Lambda" strain have been found in the United States, and the Japanese government has also reported it.

In the United States, more than 1,000 cases of infection with the "Lambda" strain have been reported

It is reported that although the number of confirmed cases of COVID-19 in the United States infected with the "Lambda" strain is much smaller than the number of cases infected with the Delta variant, some infectious disease experts said that the "Lambda" strain is also a variant they are paying close attention to. Malani, an expert from the American Society of Infectious Diseases, said that it is still difficult to determine how contagious this strain is.

The Ministry of Health, Labor and Welfare of Japan also reported that the country has confirmed the first case of COVID-19 infected with the "Lambda" strain. It is reported that on July 20, the infected person flew from Peru to Japan's Haneda Airport and was diagnosed with COVID-19 during entry quarantine. Genetic analysis confirmed that the infection was the "Lambda" variant strain. The Ministry of Health, Labor and Welfare said that the variant is still being analyzed.

In addition to the United States and Japan, according to the data of the World Health Organization in July this year: since it was first discovered in Peru in August last year, the "Lambda" strain has appeared in about 30 countries and regions, especially in Chile, Peru, Ecuador and other South American countries. The spread has accelerated significantly. Among them, Chile has the largest number of cases of infection with this strain, accounting for 31% of the total number of such cases known to the WHO. The data of the Public Health Agency of England in July this year also showed that in addition to South America, countries and regions such as the United States, Canada, Germany, Spain, Israel, the United Kingdom and Zimbabwe have also reported cases of infection with the "Lambda" strain.

WHO: Lambda is one of the mutant viruses that "needs attention"

The "Lambda" strain is spreading in many places around the world. How did it get the name "Lambda" and how contagious is it?

The World Health Organization released a report on June 14 this year, naming the C.37 strain first discovered in Peru after the Greek letter λ (lambda) and listing it as one of the "mutated viruses that need attention". According to the WHO's standards, if the spread of a "mutated virus that needs attention" accelerates further and becomes serious to a certain extent, such as the need to adjust existing epidemic prevention measures, it will be upgraded to a "mutated virus that needs attention".

The report said that the spike protein of the "Lambda" strain has several genetic mutations, which may make it more contagious and more resistant to neutralizing antibodies, but the evidence currently available is insufficient to confirm the full impact of these mutations. Further research is needed to determine the necessary countermeasures for this strain.

News link: Evolving variants of the novel coronavirus

Since the outbreak of the COVID-19 epidemic, a variety of mutant strains have emerged, making the epidemic prevention and control situation in various countries more complicated. What are the characteristics of these mutant strains, and will they mutate again?

In order to facilitate public discussion and prevent stigmatization of the place of discovery, the WHO decided in May this year to name the new coronavirus variants with Greek letters. So far, the WHO has listed four "variants of concern" on its official website, namely: Alpha, Beta, Gamma and Delta.

The Alpha strain was first discovered in the UK in September last year and swept the UK at the end of the year. In April this year, it became the main mutant strain worldwide. A key mutation of the Alpha strain is that it becomes easier to bind to the cell surface, thereby entering the cell to replicate itself, which significantly enhances the virus's infectiousness.

The beta strain was first discovered in South Africa in May last year. Currently, related cases have been found in more than 100 countries around the world, but this strain currently accounts for a relatively low proportion of global infections. The gamma strain was first discovered in Brazil in November last year and is the main strain of the new coronavirus in South America. The key mutations of the beta and gamma strains are a certain degree of immune escape, which can avoid being tracked by the immune system. This means that these two strains will reduce the effectiveness of some therapies, weaken the protective power of the new coronavirus vaccine, and increase the possibility of reinfection for those who have been infected with the new coronavirus.

The Delta strain, which is currently spreading rapidly, was first discovered in India in October last year. It has mutations that increase both infectivity and immune escape, so it was initially called a "double mutation" strain. Studies have shown that the Alpha strain is 50% more contagious than the original strain, while the Delta strain is 60% more contagious than the Alpha strain.

According to the US Centers for Disease Control and Prevention, the high contagiousness of the Delta strain is comparable to that of the chickenpox virus, and is more contagious than viruses such as SARS, smallpox, and seasonal influenza. Each person infected with the Delta strain can infect an average of 8 to 9 people.

A study published in July showed that patients infected with the Delta strain were first detected on average four days after exposure to the virus, meaning the incubation period was four days, compared to six days for patients infected with the original strain, indicating that the Delta strain replicates much faster. In addition, the viral load of patients infected with the Delta strain is 1,260 times that of the original strain, and the time to turn negative is 13 to 15 days, significantly longer than the 7 to 9 days of the original strain. At present, at least 132 countries around the world have reported cases of infection with the Delta strain, and the detection rate of the Delta strain in some countries exceeds 80%.

At the end of July, the World Health Organization predicted that the Delta strain would soon surpass other variants and become the most dominant strain in the world in the coming months.

In addition to the four "variants of concern", the WHO also listed four secondary "variants of concern". Among them, the "Lambda" strain, which was first discovered in Peru in December last year, has recently shown a tendency to spread.

Source: CCTV Finance

Editor: Wang Yuanfang

Editor: Chang Ying Zhang Yongqun