First Questions and Answers: What is a Virus?

Our lives have been taken over by a tiny virus we can\'t even see. But what IS a virus? How do viruses spread? Why should everyone keep washing their hands? How does a vaccine work? And what can we do to STAY WELL? Lift the flaps to find out. Σελίδες: 12, Διαστάσεις: 19x19cm