Chickenpox

A common, mild infectious disease (also called varicella) occurring in childhood and characterized by a rash and slight fever. In adults, chickenpox is rare but usually more severe. An attack gives lifelong immunity, but the virus remains dormant in nerves and may reappear later in life to cause herpes zoster (shingles). The cause of chickenpox is the varicella-zoster virus, which is spread in airborne droplets. A widespread rash develops 2–3 weeks after infection, consisting of clusters of small, red, itchy spots that become fluid-filled blisters within a few hours. After several days the blisters dry out to form scabs. Scratching the blisters can lead to secondary infection and scarring. Paracetamol helps reduce fever and calamine lotion may be used to relieve itching. In severe cases, aciclovir (an antiviral drug) may be prescribed.