Lambda coronavirus variant: What you should know

The lambda variant is dubbed a "variant of interest" by WHO, but some experts say we should be concerned. Here's what we know.

Jessica Rendall Wellness Writer
Jessica is a writer on the Wellness team with a focus on health news. Before CNET, she worked in local journalism covering public health issues, business and music.
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As the coronavirus continues to mutate and wreak havoc, some variants that pop up are more contagious and lead to more severe disease, and are therefore more concerning than others. Variants such as alpha and (especially) delta have proved to be more transmissible and potentially lead to more hospitalizations than the original virus. But until a variant begins circulating in communities or squares up against coronavirus vaccines, there's a lot of guesswork involved when it comes to how concerned, exactly, we should be.

A variant popping up as the dominant variant in an increasing number of countries is lambda, called a "variant of interest" by the World Health Organization, which first documented the strain in Peru in December. It's the dominant strain in Peru, a country of about 32 million people that has lost about 197,000 citizens to COVID-19, according to Johns Hopkins data. Lambda is now the dominant variant in Argentina, Brazil, Chile and Colombia, according to Forbes.

Lambda is a variant of interest -- but should we be concerned?

WHO designates variants of interest if there is substantial community transmission of the variant, and if scientists detect genetic changes that could make the variant more contagious or severe. Right now, experts seem to be on the fence about how seriously the public should take the lambda variant's presence in the US and in the world. Those who say we should pay close attention to lambda point out the variant's course in South America and the way it appears to have developed mutations that make it easier to jump from person to person. 

"I think anytime a variant is identified and demonstrates the capacity to rapidly spread in a population, you have to be concerned," Dr. Gregory Poland, a professor of medicine and director of the Vaccine Research Group at the Mayo Clinic in Rochester, Minnesota, told CNN on Friday.

"There are variants arising every day -- if a variant can be defined as new mutations," Poland said. "The question is, do those mutations give the virus some sort of advantage, which of course is to human disadvantage? The answer in lambda is yes."

Lambda has been identified in the US, but not in significant numbers. Delta remains the dominant variant in the US. However, worries were fueled after a study (which hasn't been peer-reviewed) published at the end of July found that a mutation in lambda's spike protein makes the variant more infectious, and that lambda has the potential to evade neutralizing antibodies.

So far, there's no research to suggest that the three vaccines available in the US won't be effective against lambda. Preliminary studies (not yet peer-reviewed) show that while antibodies induced by Pfizer, Moderna and CoronaVac (a Chinese COVID-19 vaccine) were less powerful against lambda than the original strain, they still "neutralize" the virus and are expected to be effective against lambda. It's also important to note that this seems to be the case for pretty much every coronavirus variant, as all three US vaccines were developed after the original coronavirus had begun mutating and other variants of the virus were already circulating. 

Vaccines and mutations

As long as a significant portion of the world's population remains unvaccinated or without immunity to the coronavirus, it will keep mutating and more variants will form. It's difficult to gauge the danger of lambda's prevalence in Peru, which has a population that's about 19% fully vaccinated and without the vaccine access that countries like the US have.

Dr. Preeti Malani, chief health officer in the division of infectious diseases at the University of Michigan in Ann Arbor, told CNN that controlling the spread of COVID-19 in general will help manage the lambda variant. "It's a race between getting enough of the world vaccinated and the development of new variants that are less responsive to countermeasures," Malani said.

Dr. Anthony Fauci, President Joe Biden's chief medical advisor, said that as long as a good portion of the population remains unvaccinated, we will see new variants emerge (such as the delta plus variant), and that raises the risk of potentially more dangerous ones that can break through our current vaccines' protection against severe illness and death. 

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.