An mRNA vaccine with a twist—it copies itself—protects against COVID-19

Fuller says a self-amplifying mRNA COVID-19 vaccine ideally would replace the two primary doses, giving it an even clearer benefit over its conventional relatives. A booster months later might still be warranted, as is encouraged now for the current mRNA vaccines. But self-amplifying mRNAs could also lead to more durable immune responses, Fuller suggests.

Read more in Science.