Is the covid-19 vaccine effective against the Lambda variant?
Despite the Delta variant dominating the latest covid-19 wave across the US, a new 'variant of interest' named Lambda is being monitored by the CDC.


Do vaccines work against the Lambda variant?
As not many tests have been run on the variant, it is unknown how effective vaccines will be. However, if the other variants are considered, then it is likely that the vaccines will work, if extra protectin is given. The only vaccine tests have yet to be peer-reviewed but suggest that three mutations, called the RSYLTPGD246-253N, 260 L452Q and F490S, could make the variant more resistant to vaccines. Another paper, from July suggested that booster doses, including for the Janssen vaccine, were needed to protect against changing variants. More testing will need to happen before the potential danger can be fully ascertained.
Despite first being sequenced in an April sample in Texas, the number of the variant remains low. Therefore, it is unlikely to be more transmissible than the Delta variant which is currently dominating all other variants.
"Lambda has mutations that are concerning but this variant remains quite rare in the US despite being around for several months," Dr. Preeti Malani, chief health officer in the division of infectious diseases at the University of Michigan, wrote, "It's difficult to know for certain how transmissible Lambda is and how well vaccines work. So far, it seems that Lambda is more transmissible than the original [covid-19] virus," which is similar to Delta and other variants."
Delta is currently classed as a 'variant of concern' by the WHO, while Lambda is currently a 'variant of interest.' This could be increased after more testing and experiments on Lambda.
Information about the Delta variant:
- Can you get a covid-19 booster shot in the US?
- How effective are masks against the Delta variant?
- What has Dr Fauci said about the covid-19 Delta variant and lockdowns?
- How many variants of covid-19 are there and which are the most deadly?
Why are variants so dangerous?
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The more a virus transmits around a large group of people, the higher the chance that the virus will mutate. Exposing large amounts of people to a virus then becomes more dangerous, as there could be a variant in the future which is resistant to vaccines. That is not the case currently and an efficient distribution of vaccines remains the best way to stop the spread of covid-19.
More infectious, more immune-evading, more virulent SARS-CoV-2 variants will emerge wherever we allow the virus to run through unvaccinated populations.
— Céline Gounder, MD, ScM, FIDSA 🇺🇦 (@celinegounder) August 5, 2021
Delta emerged from India.
Lambda emerged from Peru.
WE NEED TO GET VACCINES TO UNVACCINATED PEOPLE AROUND THE WORLD — NOW. pic.twitter.com/yxaIiThOah
What do we know about the Lambda variant?
Information about the variant is quite scarce as it has only recently been sequenced. It was first discovered in Peru, where it now makes up more than 81% of all covid-19 cases. It is thought to be slightly less infectious than Delta. Genomic sequencing has identified 1,060 cases of covid-19 caused by the Lambda variant in the United States so far, according to the independent data-sharing initiative GISAID.

