The Delta variant of the SARS-CoV-2 virus now accounts for nearly all of the coronavirus infections globally, fuelled by the unchecked spread of the novel coronavirus in many parts of the world.
So far, vaccines are still able to defend against serious disease and death from Delta, but scientists remain on alert.
Virus experts are closely watching the evolution of the Delta variant, looking for any sign that it has acquired mutations that would allow the highly transmissible variant to pierce the immune protection of vaccines and natural infection.
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