Haemophilus influenzae Infections Following Licensure of the Hib Vaccine

To the Editor: In April 1985, the Food and Drug Administration licensed the Haemophilus influenzae type b (Hib) vaccine for use in the United States, after a field trial had confirmed its efficacy.¹ This vaccine, prepared from the capsular polysaccharide of the bacterium, has been envisioned as a cost-effective agent for reducing morbidity and mortality due to H. influenzae type b disease.² Both the Immunization Practices Advisory Committee and the American Academy of Pediatrics have recommended universal vaccination for children 24 months of age.^3,4 The U.S. Public Health Service has recommended that consideration be given to vaccinating children at high…