Hib-DTP vaccine (Easyfour) (Panacea Biotec)

Sir .—In 1977 the National Childhood Immunization Initiative began, with the goal to raise immunization levels to greater than 90% of all vaccine-preventable diseases in the nation's children. Although the incidence of these infections has significantly declined in the United States, a substantial number of cases continue to be reported in the 1980s. 1 When the age and immunity status of affected children are known, it is clearly evident that at least half of the cases were potentially preventable. In 1982 and 1983, 68% of reported pertussis cases in children 3 months to 6 years old did not have adequate immunization with diphtheria-tetanuspertussis (DTP) vaccine. 2 In addition, 20.6% of all cases of measles in the first half of 1985 occurred in children 15 months to 4 years of age, and 69.2% of measles cases in preschool-age children were preventable. 3 While specific laws require proof of adequate immunity for