Have you ever had the chicken pox? This common childhood illness has another name—the varicella zoster virus. Like all viruses, varicella replicates itself, spreading though the body, and eventually appearing as itchy red blisters all over the body. But the virus doesn’t stop there; it can spread to other people through physical contact and through the air when an infected person coughs or sneezes. It’s not a very fun illness to have.