As the new coronavirus variant Delta rages, another virus variant, Lambda, is attracting the attention of public health authorities and experts. This variant has now been found in more than 30 countries worldwide and has been classified by the World Health Organization as a “virus variant of concern”.
What is the Lambda virus variant?
The Lambda virus variant, also known as C.37, was first identified in Peru in December of last year. The World Health Organization reported in mid-June that 81% of new cases of coronavirus pneumonia sequenced in Peru since April were linked to the Lambda virus variant. The Financial Times reported that at the time the Lambda virus variant was first discovered, this virus variant accounted for only one of 200 samples of new coronavirus cases in the Peruvian capital, Lima.
Cases of infection with the Lambda virus variant have now been found in 31 countries worldwide, including six other South American countries such as Chile and Argentina, the United States, Mexico, the United Kingdom, Spain and Germany.
The World Health Organization classified Lambda as a “variant of interest” on June 14, saying further research and evaluation is needed to determine whether Lambda will evolve into a “variant of concern The “noteworthy virus variants” are
“Notable virus variant” vs. “virus variant of concern”
Since the outbreak of New Coronavirus in Wuhan, China in late 2019, the virus has continued to mutate as the number of infections has increased and the outbreak has continued. Many viral variants do not cause additional harm to humans, but there are some viral variants that have significantly increased transmissibility and pathogenicity or make existing public health interventions or vaccines less effective.
Virus variants that meet all three of these criteria are classified as “viral variants of concern”. There are currently four virus variants classified by WHO as “viruses of concern,” including the highly transmissible Delta virus variant that recently emerged in India and has spread to more than 90 countries worldwide.
Virus variants are classified as “notable” if they cause only community transmission or spread across multiple countries and territories. WHO currently classifies four new coronavirus variants, including Lambda, as “viral variants of concern. These strains may or may not later develop into “viral variants of concern”.
Lambda more infectious?
The WHO says Lambda contains several mutations that could “potentially increase transmissibility or possibly enhance resistance to neutralizing antibodies.” Neutralizing antibodies are antibodies that are produced to protect cells from the invasion of an antigen or source of infection.
Dr. Amesh A. Adalja, a senior scholar at the Johns Hopkins University Center for Health Security, told VOA that the Lambda virus variant has “some new mutations in the stinger protein that could enhance its ability to spread.”
The researchers believe that Lambda has several unusual mutations in its stinger protein, including one called L452Q. This is similar to the L452R mutation that occurs on the Delta virus variant, which is thought to enhance the virulence of the strain. another mutation on Lambda, called F490S, is thought to cause a decrease in the neutralizing ability of host antibodies.
But whether this strain is more infectious or has higher pathogenicity needs to be verified by further studies.
WHO virologist Jairo Mendez-Rico told the media, “There is no indication that the Lambda virus variant is more aggressive. It may demonstrate a higher infection rate, but we don’t yet have enough reliable data compared to Gamma or Delta virus variants.”
Are existing vaccines effective against Lambda?
There are not enough studies to show whether existing vaccines are effective against the Lambda virus variant.
In a paper that has not been peer-reviewed, Chilean researchers say that the variant produced by the Lambda stinger protein has a high level of “immune escape” (immune escape) against neutralizing antibodies produced by the CoronaVac vaccine developed by Kexing in China. The paper, published in MedRxiv, did not examine the effectiveness of other vaccines against Lambda.
Another non-peer-reviewed paper published in BioRxiv by researchers at New York University School of Medicine shows that Pfizer and Moderna’s messenger RNA vaccines are still effective against Lambda. The paper says that while Lambda “showed partial resistance” to antibodies produced by the vaccine, this resistance “is unlikely to result in a significant loss of protection from infection.”
Is Lambda a cause for concern?
The CDC does not currently list Lambda as a “notable virus variant” for new coronaviruses, but the agency notes that the virus continues to mutate and that the CDC monitors the emergence of variants and mutant strains of the virus in the United States through sequencing, laboratory studies and epidemiological investigations.
Currently, Delta virus variants remain the primary epidemic strain and are causing additional concern. In the U.S., one in four new confirmed cases of new coronavirus now infects with a Delta virus variant.
But the emergence and spread of the Lambda virus variant underscores the importance of vaccination, health experts say.
The main vaccine currently in use still appears to be effective,” said Dr. Adalia of Johns Hopkins University. While it remains unclear whether Lambda is more dangerous, this development underscores the need for accelerated vaccination.”