Epidemiology of pertussis in a developed country with low vaccination coverage: the Italian experience.

In Italy pertussis vaccination is optional. Fewer than 40% of children younger than 5 years of age are vaccinated, and pertussis remains a common childhood disease. We use data from a variety of sources to examine trends and characteristics of Italian children with pertussis and reasons behind the low vaccine coverage. Approximately 25% of Italian children have experienced clinical pertussis by their fifth birthday. The disease is most severe in those less than 1 year of age; in this group an estimated 1 in 14 cases are hospitalized and 1 in 850 die. The incidence appears to be increasing in the 1- to 4-year age group despite increased vaccination coverage. The low vaccine coverage appears to be caused by the ambivalence of the Italian pediatric community about the vaccine rather than parental concerns about vaccine safety. Legislation is being considered to make pertussis vaccination mandatory.