As the UK surpasses its goal of vaccinating 15 million people by the 15th of February, we're taking an in-depth look at COVID vaccines: how they work, what efficacy really means, and will they protect us against viral variants? Plus, in the news, updates to the list of COVID symptoms to watch out for; Chris Packham on the animal Einsteins giving humans a run for their money; and how scientists are using whale songs to explore the ocean floor... Like this podcast? Please help us by supporting the Naked Scientists