It was mid-June when the World Health Organization announced the classification of the Lambda variant of the covid, identified for the first time in Peru in August 2020 and already present in several countries, particularly Latin American, as a ‘variant of interest’ (Voi ). The epidemiologist Maria Van Kerkhove, expert at the head of the WHO technical group for the new coronavirus, reiterates the need to monitor it and WHO’s commitment in this regard. All while a Japanese study, not yet peer-reviewed, turns on a ‘red light’: the Lambda variant could create problems with vaccines.
Its Spike protein, observed the authors (scientists from the University of Tokyo and several Japanese universities) in the work available on the ‘Biorxiv’ platform, is highly infectious and this is attributed to the presence of two mutations in particular. A third mutation, however (RSYLTPGD246-253N, a deletion of 7 amino acids in the N-terminal domain of the Spike), would be responsible for evasion of neutralizing antibodies. Together with two others (L452Q and F490S), it would confer resistance to antiviral immunity. “Our data – experts warn – suggest that the insertion of this mutation is closely associated with the massive spread of Lambda variant infection in South America”.
Lambda “is one of the variants that WHO is tracing in the world – Kerkhove clarified in recent days, recalling the concept also on Twitter – It has been reported in more than 40 countries and what we are looking at right now is how well it circulates and how much transmission increases “. At this time, however, Lambda does not seem to “take off, after it has been reported in one country. There are various mutations in the Spike protein and even some deletions of amino acids. Any change in the virus poses some threat to the functioning of the vaccine,” points out. WHO expert.
The scientists who signed the study on the variant in question speak of a certain “resistance to vaccine-induced immunity” and underline how Lambda has two fundamental characteristics for efficient diffusion and transmission in the human population. Experts note that, “because the Lambda variant is classified as a variant of interest, one might” be tricked into “thinking that it is not as present a threat as the variants of concern. However, due to the demonstrated relative resistance, it could cause infections. ‘breakthrough’ “, in the vaccinated.
Scholars also recall the case of Chile, where the vaccination rate quickly became relatively high (in June, 60% of the vaccinable population had done at least one dose). In this country, the authors say, “there was an increase in cases in the spring of 2021, suggesting that the Lambda variant is adept at escaping antiviral immunity.”
“At the moment – observes Kerkhove – we have classified Lambda as a variant of interest globally, but this does not mean that it is less important. It is a variant on which we have actively discussed and we are actively trying to collect as much information as possible. from every available source “.