There is concern over the threat posed by the Lambda variant of COVID-19 which may be more resistant to vaccines than the original version of the virus.
Research by a team from the University of Tokyo, which has not yet been peer-reviewed, found that three mutations in Lambda's spike protein help it resist neutralization by vaccine-induced antibodies.
Meanwhile, two mutations in the Lambda variant—T76I and L452Q—make it more infectious than the COVID variant that swept through the world in 2020.
The conclusions of the study posted on BiorXiv on July 28 matched findings—also not yet peer-reviewed—by a team in Chile that found the variant might also evade vaccine antibodies, Infection Control reported.
It said Lambda, also known as the C.37 variant, has been the COVID-19 carrier in about 81 percent of infections in Peru since April. Cases have been found in 29 countries, territories or areas within five WHO regions.
However, the Japanese researchers said that the threat of the variant might be underestimated given that it was only named as a "variant of concern."
"Lambda can be a potential threat to the human society," senior researcher Kei Sato of the University of Tokyo said, according to Reuters.
Dr. Georg-Christian Zinn, who is director of the Bioscientia Hygiene Center, in Ingelheim, Germany, said that the statement by the Japanese team should be taken seriously even if their findings still need to be verified.
"The new Japanese preprint study on the Lambda variant is very, very credible," he told RTL.de, according to a translation of his comments. He referred to the expertise of the researchers, adding, "the data are valid."
Pablo Tsukayama, a doctor in molecular microbiology at Cayetano Heredia University in Lima who documented Lambda's emergence said that when it was discovered, "it did not attract much attention."
By March 2021, it was in 50 percent of the samples in Lima but only a month later, it was in 80 percent of the samples in Peru. "That jump from one to 50 percent is an early indicator of a more transmissible variant," Tsukayama told Al Jazeera in July.
Meanwhile, Dr. Stuart Ray professor of medicine at the Johns Hopkins Hospital, told NPR in July that Lambda is "sort of a cousin of the alpha variant" but evidence so far is not clear that it has any advantage over the highly contagious delta variant.
"Delta is clearly dominating right now. And so I think our focus can remain on Delta as a hallmark of a highly infectious variant," he said.
"We have to be vigilant for these new variants and track them," he said. "I think right now lambda is a variant of interest, and we'll see whether it becomes a variant of concern."