Andddd there’s another variant of interest

Officially it’s called Lambda 

It’s been around for a while, as it was first discovered in Peru during the summer of 2020. Lambda started gaining speed in December 2020 and now represents 71% of cases in Peru. It’s been blamed for the recent case loads in South America. 

Lambda has also been detected in 27 other countries, including, most recently, the UK and Canada. It has been detected in the United States, but it’s circulating at very low levels for now. 

Variant of Interest

On June 15, the World Health Organization named Lambda a Variant of Interest (VOI). They’ve been monitoring it for quite a while, but not until recently has it met official criteria: Lambda is starting to pick up speed and spread quickly across the globe.

A “Variant of Interest” is a less severe classification than “Variant of Concern”. But this doesn’t mean that the WHO isn’t keeping a close on eye on it. If scientists start seeing increased transmissibility or disease severity on a global scale, the WHO will bump up the classification. The escalation of classification is exactly what happened with Delta. 


There are a number of mutations on Lambda, including 6 changes on the spike protein. We pay attention to spike mutations because the spike is the key to our cells. If the virus is changing the key, we need to know about it. 

We are familiar with some of these spike mutations already:

  • One of the mutations (called T859N) is also on the variant first detected in New York (called Iota; also a Variant of Interest). 

  • Lambda also has a mutation called D614G which is now on almost all the variants. It’s been shown to cause increased transmissibility. 

In addition, Lambda has two new mutations that we’ve never seen before: L452Q and F490S. The L452Q change is similar to a mutation on Delta, so we hypothesize that Lambda has increase transmissibility too. Given the novel mutations, laboratory and “real world” studies are desperately needed to see how well our vaccines react to the new changes. 

Should we be worried?

In the short-term, probably not, but we are still gathering evidence. 

Preliminary evidence showed the possibility of Lambda escaping immunity. Also, on July 1, scientists published a preprint (i.e. not peer reviewed yet) study that found Lambda’s “increased infectivity and immune escape from neutralizing antibodies elicited by CoronaVac”. Basically they found that Lambda could escape the CoronaVac vaccine (a vaccine commonly distributed in Asia). 

On the other hand, a study on July 3 reported a relatively minor (3-fold) decrease in neutralizing antibodies when Lambda was introduced to the mRNA vaccines. This means that Pfizer and Moderna’s efficacy is probably decreased “a little but not a lot” and will still offer protection against severe disease. The authors said they’re testing J&J and will have results soon.

There continues to be concern in the long-term, though. One underlying theme throughout all the studies was that this is not a good sign; this virus continues to mutate in a dangerous way and we continue to play with fire. As the authors in the mRNA study stated:

“The results do not preclude the possibility that novel variants will emerge that are more resistant to current vaccines. The findings highlight the importance of wide-spread adoption of vaccination which will protect individuals from disease, decrease virus spread and slow the emergence of novel variants.” 

Bottom Line

Pay attention to the broader landscape. High transmission and mutations in Peru directly impacts us. This is, after all, a global pandemic. But I wouldn’t worry about the Lambda headlines just yet. Delta is a far more dangerous, immediate threat to the United States. 

Love, YLE