A group from University of Colorado, Aurora, USA, etc. has reported that SARS-CoV-2 Lambda variant has higher infectivity than Delta variant.
https://pubmed.ncbi.nlm.nih.gov/34462744/
The binding affinity of overall antibodies from Pfizer-BioNTech vaccinated individuals droped dramatically (about 3.5 times fold drop for the Delta variant, and about 4.0times fold for the Lambda variant) after six months. These data suggest that the Lambda variant has a better chance than the Delta variant to escape the immunity built by the vaccination.
Although the mutations of L452Q and F490S in RBD of Lambda varient do not bring any enhance of the binding between RBD and ACE2 comparing with Delta variant, both mutations lead to the disruptions of a hydrophobic patch, which is a critical area for the binding of broadly neutralizing antibodies. This could be a reason why Lambda variant has higher infectivity than Delta variant.