Chickenpox infection is known mostly to affect children with a rash that is less painful and more diffused. Herpes zoster is the reactivation of the VZV, affecting older people, as the efficiency of the immune system declines with age, and tends to be more painful and sometimes serious, particularly if it occurs on the face. The virus spreads from person to person by airborne droplets while sneezing or coughing. It can also spread by direct contact with the chickenpox or herpes lesions. Isolating infected children by keeping them away from school will help, but only vaccination will help reduce the spread of chickenpox.
Transmission is most likely within the first two days before the appearance of the rash.
Chickenpox is contagious for up to five days of the rash but not after day 6 and generally, children can go back to school after this time. Many people contract chickenpox during childhood or adolescence, but adults who have escaped the infection earlier will at some time or the other get infected. Chickenpox infection then can be severe and lead to complications. The most obvious is the blistered and highly itchy rash, which can last for up to 10 days. Fever is probably the most common clinical sign along with chills, nausea and vomiting.