How worried should you be about Lambda? 7 critical facts about the variant

Like a horror movie villain who just won’t die, the novel coronavirus keeps mutating in new and dangerous ways.

In the United States, the more transmissible and infectious Delta has been ravaging unvaccinated communities and causing a few breakthrough infections in the vaccinated. Now, there’s another variant raising disturbing questions that scientists are scrambling to answer: the Lambda variant.

Delta is still the dominant variant in the United States, but Lambda hit South America hard, and infections of the variant are now showing up throughout the U.S. The rapid spread of these variants raises crucial questions about how affected our lives will be by the coronavirus in the months and years to come.

Krutika Kuppalli, vice-chair of the IDSA Global Health Committee and assistant professor at the Medical University of South Carolina, tells Inverse, “We know little about Lambda in terms of transmission and virulence, but this is one we should keep an eye on.”

Here’s what we do and don’t know about the Lambda variant and how experts are thinking about the future of coronavirus.

7. What is the lambda variant, and where did it come from?

According to the World Health Organization (WHO), the lambda variant was first identified in Peru in August 2020. According to the WHO, it spread quickly and by Spring of 2021 was responsible for about 81 percent of Covid-19 infections in Peru and had been reported in 28 other countries and territories.

Lambda is currently designated a “Variant of Interest” by the World Health Organization. Some researchers are pushing the WHO to bump Lambda up to a “Variant of Concern,” arguing its mutations are a real cause for alarm.

6. What mutations make the lambda variant different?

Lambda has several mutations. Some are the same mutations we’ve seen in other variants, but at least one appears to be native to the variant. The unique mutation that’s causing concern is on the spike protein. It’s called the RSYLTPGD246-253N mutation, and it gives the virus more affinity for the ACE2 reception, which is how it enters human cells. This makes the virus more infectious.

Initial research suggests it’s this mutation that gives lambda some antibody evading power. While it’s not uncommon for a virus to evade some antibodies, the big question is if it can evade enough antibodies to cause breakthrough infections and severe disease in vaccinated people.

5. Do we know how it compares in transmissibility to the original strain and to Delta?

It’s not yet clear how Lambda compares to Delta in terms of transmissibility, severity, and vaccine evasion — but like Delta, Lambda appears to be more transmissible than the original (or “wild type”) version of SARS-CoV-2. It shares two mutations with variants we know are more transmissible than the wild-type virus: one with Alpha and one with Delta.

Some researchers suggest that Lambda is more transmissible than Alpha and less transmissible than Delta. This means it may not spread as quickly as Delta but may spread quickly through areas where Delta is less present, making outbreaks harder to contain.

4. Do we know anything about how Lambda responds to vaccines?

In a pre-print study, investigators with the University of Toyko found that Lambda may be more resistant to vaccines than the original strain of the virus, says Kuppalli. The crucial question of how much resistance to each of the vaccines is still an open question.

For example, Delta shows some antibody resistance, leading to breakthrough infections in vaccinated people, but the vast majority of those cases are mild. We don’t yet know if the same will be true for Lambda, but continuing to use masks and social distancing will reduce breakthrough infections of both Delta and Lambda.

The type of vaccine also matters. Lambda is making noise because a pre-print study showed that Sinovac/Coronavac might not protect against the Lambda variant very well. Still, other variants succeed in evading antibodies from that particular vaccine.

3. How many more variants should we be expecting?

That depends entirely on global vaccination rates. Currently, 29.6 percent of the world population has received at least one dose of a Covid-19 vaccine, and only 15.2 percent is fully vaccinated. Those numbers need to significantly increase to slow the evolution of more variants.

2. What will finally stop variants from emerging?

To finally quash SARS-Cov-2 and its variants, Kuppali says, “We are going to need global vaccine equity and will need to have vaccine uptake around the world and to decrease levels of circulating virus.”

With widespread vaccine adoption, three important things happen:

3. Less virus will circulate

2. More people will be protected from severe disease

1. There will be fewer chances for the virus to develop significant mutations

Ultimately, this will reduce the number of variants and the number of people who contract infections and severe disease.

1. Will Covid-19 become endemic?

The virus is going to become endemic, Kuppalli says. When a virus is endemic, it appears regularly in a population; for example, the flu is an endemic virus because it regularly occurs.

What we need to do to mitigate the harm of endemic Covid-19 is “increase vaccine uptake to the point that there are fewer hosts that can develop serious infection and so it becomes akin to other nuisance respiratory viral infections which are unpleasant for people to deal with but are not life-threatening.”

While there’s much we don’t know about Lambda, one thing is clear: the way to protect yourself, your community, and prevent more variants from occurring is to get vaccinated. While so much of the world is unvaccinated, Kuppalli says, “People who have been fully vaccinated should also employ other mitigation measures such as use masks and social distancing to protect themselves and others.”