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How effective are vaccines in protecting against the new variants of the virus?

As the SARS-CoV-2 (COVID-19) virus continues to mutate, a key question remains: how effective are vaccines in protecting against the new variants of the virus? 

Two studies out of the UK set out to answer this question.  

The first study from Francis Francis Crick Institute, the National Institute for Health Research and the UCLH Biomedical Research Centre published a study (https://lnkd.in/gNMsvZ4) in early June focused on answering this question by testing antibody levels (Previous clinical studies have shown that antibody levels are a predictor of the efficacy of vaccines) from double vaccinated blood samples against various strains of the virus. 

After two doses of the vaccine, levels of neutralizing antibodies were found to be 5.8 times lower when tested against the Delta variant than the original COVID-19 strain that current vaccines were tested against. 

After one dose of the vaccine, only 32% of the blood samples had a quantifiable antibody response to the Delta variant. 

The second study (https://lnkd.in/gMFha_R), published by Oxford University, noted that there was “no evidence of widespread escape, suggesting that the current generation of vaccines will provide protection against the B.1.617 lineage.”  However, they noted there was reduction in neutralizing antibodies, which could lead to breakthrough infections. 

For our part at Haven Testing, we believe that given the question of efficacy of vaccines on more transmissible variants like the Delta, rapid antigen screening is as important as ever. In Canada, we’re making significant progress in getting everyone vaccinated, but we need to remain vigilant in screening.