The incidence of Hib [Haemophilus influenzae type b] disease among children aged less than 5 years declined from 1989 to 1993 but was stable from 1993 to 1994.
During 1988-1992, the incidence of invasive Hib disease declined rapidly among children; however, the findings in this report indicate that, since 1992, the rate of decline among children has slowed.
Surveillance data indicate that a decreasing proportion of Hi [Haemophilus influenzae] cases are caused by Hib [type b]…
[D]ata from laboratory-based surveillance suggests that, during 1993-1994, incidence of Hib disease remained stable.