As the lambda variant rages across South America, researchers wonder whether it poses a risk to vaccine efficacy.
The Coronavirus lambda variant was first spotted in Peru in December of last year. Since then, it has travelled to more than 20 countries around the world. Recently, the World Health Organization (WHO) added it to its ‘variant of interest’ list. Currently, the list contains four designated variants of interest: Eta, Iota, Kappa, and Lambda. As per WHO’s definition, a variant of interest is one with ‘genetic changes that are predicted or known to affect virus characteristics such as transmissibility, disease severity, immune escape, diagnostic or therapeutic escape’. Moreover, the variant must pose a risk to global public health through an increasing prevalence across multiple countries.
Lambda has been associated with substantive rates of community transmission in multiple countries, with rising prevalence over time concurrent with increased COVID-19 incidence.
World Health Organization
The Lambda variant carries several unusual mutations within its spike protein. One of the mutations, L452Q has never before occurred in any of the other variants. Researchers predict that it can likely help the virus bind more strongly to human cells and prevent antibodies from neutralizing the virus. Thus, pointing to a lower vaccine efficacy against the variant.
Not a Concern, Yet
The mutated virus has caused increasing cases and hospitalizations in several South American countries. It currently accounts for more than 80% of new COVID-19 cases in Peru. Moreover, according to the country’s revised figures, more than 0.5% of the population has died from COVID-19 so far. With 596 deaths per 100,000 people, the country has the highest death toll in the world. Additionally, its neighbour, Chile has also reported a sharp increase in cases despite more than half the population already being vaccinated with Sinovac. Thus, causing researchers to wonder whether the Chinese vaccine is effective against the new variant.
Recently, researchers at the University of Chile investigated the Sinovac vaccine’s efficacy against the lambda variant. The preprint study found a threefold decreased antibody response against the variant as compared to the Alpha and Gamma strain.
Our results indicate that mutations present in the spike protein of the Lambda variant of interest confer increased infectivity and immune escape from neutralizing antibodies elicited by CoronaVac (Sinovac)
study authors
However, it is far too early to concur whether the variant poses a risk similar to the deadly Delta variant that’s wreaking havoc across the world. For now, researchers have decided to keep a close eye on the variant. They are also urging people to receive both doses of the vaccines, irrespective of the vaccine; as any vaccine is better than no vaccine.
Reference:
Acevedo, M. L., Alonso-Palomares, L., Bustamante, A., Gaggero, A., Paredes, F., Cortés, C. P., Valiente-Echeverría, F., & Soto-Rifo, R. (2021). Infectivity and immune escape of the new SARS-CoV-2 variant of interest Lambda. https://doi.org/10.1101/2021.06.28.21259673
