January 1989

Immunization After Invasive Haemophilus influenzae Type b DiseaseSerologic Response to a Conjugate Vaccine

Author Affiliations

From the Divisions of Infectious Diseases, Departments of Pediatrics (Drs Edwards and Porch, Mss Palmer and Bradley) and Medicine (Dr Decker), and the Department of Preventive Medicine (Dr Decker), Vanderbilt University School of Medicine, Nashville, Tenn.

Am J Dis Child. 1989;143(1):31-33. doi:10.1001/archpedi.1989.02150130041012

• Fifteen children with previous invasive Haemophilus influenzae type b disease were immunized with a Hemophilus-diphtheria toxin mutant protein conjugate vaccine. Serologic responses were compared with those of 31 newly immunized children without previous invasive H influenzae type b disease. Mean levels of antibody to polyribosylribitol phosphate among study children younger than 18 months were 0.086 mg/L before immunization, 0.737 mg/L after first immunization, and 4.453 mg/L after second immunization. In contrast, the comparable mean polyribosylribitol phosphate antibody levels among control children younger than 18 months were 0.107, 3.580, and 63.502 mg/L. A similar pattern of results was found among children aged 18 months or older. Although children with previous invasive H influenzae type b disease do not respond as vigorously to conjugate vaccine as do previously healthy controls, the response is sufficient to justify routine immunization of such children.

(AJDC 1989;143:31-33)