The number of recommended vaccines that require injections has increased substantially over the last 13 years. The schedule for active immunization of healthy infants and children in 1986 involved a single vaccine injection at each of the scheduled visits according to the American Academy of Pediatrics' Red Book. The 1999 recommended schedule involves three or four injections at most visits such that by age 6 years, 12 unique antigens are administered with 16 injections (Table 1).<sup>6 American Academy of Pediatrics Committee on Infectious Diseases Recommended childhood immunization schedule—United States, January–December 1999 Pediatrics 1999 ;  103 : 182

Cliccare qui per andare alla sezione Riferimenti</sup> Combination vaccines offer the following benefits:

The demand for new combination vaccines is increasing. Given the option of multiple injections or multiple office visits, however, parents prefer multiple injections, as shown in Table 2.<sup>110 Melman S.T., Chawla T., Kaplan J.M. , e al. Multiple immunizations: Ouch Arch Fam Med 1994 ;  3 : 615

Cliccare qui per andare alla sezione Riferimenti, 178 Woodin K.A., Rodewald L.E., Humiston S.G. , e al. Physician and parent opinions: Are children becoming pincushions from immunizations? Arch Pediatr Adolesc Med 1995 ;  149 : 845

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