KEY POINTS

  • The Lambda variant is currently classified as "variant of interest"
  • Experts say three mutations in Lambda's spike protein help it resist neutralization by vaccine-induced antibodies.
  • Two additional mutations help make Lambda highly infectious
  • There are 937 cases of the Lambda variant sequenced in the US

The Lambda variant of the coronavirus, which is now spreading in South America, appears to be more resistant to vaccines than the original strain of the virus, experts said.

In a paper posted last Wednesday on bioRxiv ahead of peer review, a group of Japanese researchers warned that people may not realize the threat of the Lambda variant, which is currently labeled as a “variant of interest” by the World Health Organization. 

The researchers also noted that in laboratory experiments, they found three mutations in the variant’s spike protein that help it evade vaccine-induced antibodies and two additional mutations make Lambda highly infectious. 

"Lambda can be a potential threat to the human society,” senior researcher Kei Sato of the University of Tokyo, said, according to Reuters. It remains unclear whether the Lambda variant is more dangerous than the Delta variant which is currently spreading rapidly in many countries.

The Lambda variant, also referred to as C.37, was first detected in Peru in August 2020. It was classified as a “variant of interest” on June 15 by WHO officials and was later classified as a “variant under investigation” by the United Kingdom on June 23. 

As of early July, the Lambda variant accounted for 81% of all COVID-19 cases sequenced since April in Peru. The variant has also spread across Latin America and the U.K. 

In the United States, the first case of a COVID-19 infection caused by the C.37 variant was reported by scientists at the Medical University of South Carolina. The variant was found in a virus sample taken in April from a Greenville patient. 

As of Monday, there have been 937 cases of the Lambda variant sequenced in the U.S. out of the 35,131,393 coronavirus cases recorded since the start of the pandemic, according to a database for scientists tracking COVID-19 variants. 

But the United States has only sequenced 1.37% or 480,983 samples, according to data from Johns Hopkins University. This means the 937 cases of Lambda recorded do not reflect the number of cases caused by the variant in the country. 

The Delta variant, which accounts for 83% of all new COVID-19 cases in the U.S., remains the primary concern for public health officials. 

A US shipment of Covid-19 vaccines to Africa comes as the world faces an intensifying impact from the virulent Delta strain of the coronavirus A US shipment of Covid-19 vaccines to Africa comes as the world faces an intensifying impact from the virulent Delta strain of the coronavirus Photo: AFP / Anthony WALLACE