Impact of haemophilus influenzae type b conjugate vaccine in South Africa and Argentina.
BACKGROUND
Haemophilus influenzae type b (Hib) persists as a major cause of pediatric meningitis and pneumonia in developing countries in which Hib conjugate vaccines are not used. Demonstration of decreases in severe Hib disease after countries introduce Hib conjugate vaccine will help justify the resources necessary to purchase and provide the vaccine. Because surveillance for culture-confirmed Hib meningitis is not available in many countries, alternative means to measure the impact of Hib conjugate vaccine would be useful.


METHODS
Laboratory records from the years before and after introduction of the Hib conjugate vaccine were reviewed at 4 hospitals, 2 in Argentina and 2 in South Africa. Potential indicators of bacterial meningitis including cerebrospinal fluid (CSF) culture, white blood cell count, appearance, protein and glucose were recorded.


RESULTS
After introduction of Hib conjugate vaccine, culture-confirmed Hib meningitis declined significantly at 3 of 4 hospitals (2 in Argentina and 1 in South Africa). In the same 3 hospitals, there was a significant decline after vaccine introduction in some of the following CSF indicators of bacterial meningitis: proportion of CSF specimens with white blood cell count > or = 100 x 10(6)/L, 500 x 10(6)/L and 1,000 x 10(6)/L; glucose <40 mg/dL; protein >100 mg/dL; and turbid appearance.


CONCLUSIONS
Culture-confirmed Hib meningitis declined at 3 of the 4 hospitals after Hib vaccine introduction. Surrogate indicators of bacterial meningitis also declined and might be useful measures of Hib conjugate vaccine impact at hospitals where capacity to culture Hib is not available.
Martin
Michael
M
Respiratory Diseases Branch, Division of Bacterial and Mycotic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
Casellas
Javier Maria
JM
Madhi
Shabir A
SA
Urquhart
Tamatha J
TJ
Delport
Suzanne D
SD
Ferrero
Fernando
F
Chamany
Shadi
S
Dayan
Gustavo H
GH
Rose
Charles E
CE
Levine
Orin S
OS
Klugman
Keith P
KP
Feikin
Daniel R
DR
D017677:Age Distribution; D001118:Argentina / Q000453:epidemiology; D016667:Bacterial Capsules; D002648:Child; D002675:Child, Preschool; D005260:Female; D006192:Haemophilus Infections / Q000453:epidemiology / Q000517:prevention & control*; D018073:Haemophilus Vaccines / Q000008:administration & dosage*; D006193:Haemophilus influenzae / Q000276:immunology; D006801:Humans; D017589:Immunization Programs / Q000706:statistics & numerical data; D015994:Incidence; D007223:Infant; D008297:Male; D008583:Meningitis, Haemophilus / Q000453:epidemiology / Q000517:prevention & control*; D011135:Polysaccharides, Bacterial / Q000008:administration & dosage*; D011336:Probability; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D017678:Sex Distribution; D013019:South Africa / Q000453:epidemiology
D018073:Haemophilus Vaccines; C044237:Haemophilus influenzae type b polysaccharide vaccine; D011135:Polysaccharides, Bacterial