Lambda Variant’s ‘Unusual’ Mutations May Make It Resistant to Vaccines: Researchers

Scanning electron microscope image shows the CCP virus (round blue objects), the virus that causes COVID-19, emerging from the surface of cells cultured in the lab. NIAID-RML

Scientists are concerned that a newly labeled COVID-19 variant, first detected in Peru, may be resistant to COVID-19 vaccines due to “unusual” mutations.

Researchers from the University of Chile in Santiago said in a study published in a preprint last week that the variant has “a considerable potential to become a variant of concern.”

“Our data show for the first time that mutations present in the spike protein of the Lambda variant confer escape to neutralizing antibodies and increased infectivity,” wrote researchers in the paper that has yet to be peer-reviewed.

The Lambda variant, also known as C.37, is believed to have first emerged in Peru in August last year, but has only been recognized as a potential global threat in recent weeks, with the World Health Organization (WHO) declaring it a variant of interest on June 17 after it appeared in several countries simultaneously.

The WHO said the variant’s “neutralizing antibodies” could increase its transmissibility or potentially increase its resistance. It was “associated with substantive rates of community transmission in multiple countries,” it said.

In Peru, the Lambda strain now accounts for 82 percent of new infections. Meanwhile, Chile, Argentina, Brazil, Colombia, Ecuador, and Mexico, have all confirmed widespread cases of the variant.

WHO virologist Jairo Mendez-Rico told DW that although the strain may exhibit higher infection rates, there is no indication that it is more aggressive.

Mendez-Rico told the outlet that more data is needed to compare the newly labeled strain to other existing strains such as gamma (P.1) and delta (B.1.617.2), which have already been categorized by the WHO as variants of concern.

Jeff Barrett, director of the COVID-19 Genomics Initiative at the Wellcome Sanger Institute in the UK, told the Financial Times that it is challenging to “make sense of the threat from Lambda, using computational and lab data” because it has “rather an unusual set of mutations, compared with other variants.”

According to the Centers for Disease Control and Prevention, no cases of the Lambda strain have been recorded in the United States so far.

“Considering that this variant has rapidly spread in Peru, Ecuador, Chile, and Argentina, we believe that Lambda has a considerable potential to become a variant of concern,” they wrote.

The WHO said that further studies are needed to “validate the continued effectiveness of vaccines” with the Lambda strain.