In 1984, 221,983 cases of varicella (chickenpox) were reported from 33 states and the District of Columbia. These reports make varicella the second most frequently reported infectious disease (with gonorrhea being first) in the United States. The reported incidence, based on the population of the 34 reporting areas, is 138 cases/100,000 population. As in prior years. the incidence in 1984 peaked between March and May. While the reported incidence increased 25% between 1983 and 1984, such increases have been noted in the past. There appears to be no predictable pattern to these changes in reported varicella activity. VARICELLA (Chickenpox) — Reported cases, by area and age group, selected areas, 1984 Age-specific data on reported cases of varicella were available from nine states. Cases with known age accounted for only 28% of all reported cases. On the basis of the data from states reporting by age for 1984, the 5- to 9-year age group had the highest incidence and accounted for 56% of reported cases of known age. Fewer than 6% of the patients were 15 years of age or older. |