Cause of Chickenpox & Shingles
Approximately 90% of chickenpox cases occur in children under 10 years of age. The infection is usually transmitted by airborne droplets containing the virus. Less often, the virus is spread by direct contact with the blisters. After exposure, the typical incubation period is 2 weeks. One is contagious a couple of days before the rash appears. Rarely, chickenpox is transmitted through the blood of an infected mother to a fetus.
Shingles cannot be acquired from another person. Shingles is caused by reactivation of the dormant virus. While shingles can occur at any age, more than two-thirds of cases occur in people over 50 years of age. Shingles is 20 to 100 times more common in immune compromised individuals, such as patients with chronic disease and the elderly, as well as those whose immune systems are suppressed by medication or chemotherapy. An individual who has never had chickenpox could develop the infection by coming into contact with shingles blisters.
