Incidences of vaccine-preventable Haemophilus influenzae type b pneumonia and meningitis in Indonesian children: hamlet-randomised vaccine-probe trial.
BACKGROUND
Most studies of Haemophilus influenzae type b (Hib) disease in Asia have found low rates, and few Asian countries use Hib vaccine in routine immunisation programmes. Whether Hib disease truly is rare or whether many cases remain undetected is unclear.


METHODS
To estimate incidences of vaccine-preventable Hib pneumonia and meningitis among children younger than 2 years in Lombok, Indonesia, during 1998-2002, we undertook a hamlet-randomised, controlled, double-blind vaccine-probe study (818 hamlets). Children were immunised (WHO schedule) with diphtheria, tetanus, pertussis (DTP) or DTP-PRP-T (Hib conjugate) vaccine. Vaccine-preventable disease incidences were calculated as the difference in rates of clinical outcomes between DTP and DTP-PRP-T groups. Analyses included all children who received at least one vaccine dose.


RESULTS
We enrolled 55073 children: 28147 were assigned DTP-PRP-T and 26926 DTP. The proportion of pneumonia outcomes prevented by vaccine ranged from less than 0 to 4.8%. Calculated incidences of vaccine-preventable Hib disease (per 10(5) child-years of observation) for outcome categories were: substantial alveolar consolidation or effusion, less than zero (-43 [95% CI -185 to 98]); all severe pneumonia, 264 (95% CI less than zero to 629); all clinical pneumonia, 1561 (270 to 2853); confirmed Hib meningitis, 16 (1.4 to 31); meningitis with cerebrospinal-fluid findings consistent with a bacterial aetiology, 67 (22 to 112); and admission for suspected meningitis or presenting to a clinic with convulsions, 158 (42 to 273).


CONCLUSIONS
Hib vaccine did not prevent the great majority of pneumonia cases, including those with alveolar consolidation. These results do not support a major role for Hib vaccine in overall pneumonia-prevention programmes. Nevertheless, the study identified high incidences of Hib meningitis and pneumonia; inclusion of Hib vaccine in routine infant immunisation programmes in Asia deserves consideration.
Gessner
Bradford D
BD
Association Pour l'Aide à la Médecine Préventive, Paris, France. 106617.3011@compuserve.com
Sutanto
Agustinus
A
Linehan
Mary
M
Djelantik
I Gusti Gede
IG
Fletcher
Tracy
T
Gerudug
I Komang
IK
Ingerani
Mercer
David
D
Moniaga
Vanda
V
Moulton
Lawrence H
LH
Moulton
Lawrence H
LH
Mulholland
Kim
K
Nelson
Carib
C
Soemohardjo
Soewignjo
S
Steinhoff
Mark
M
Widjaya
Anton
A
Stoeckel
Philippe
P
Maynard
James
J
Arjoso
Soemarjati
S
D016667:Bacterial Capsules; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage; D004311:Double-Blind Method; D005260:Female; D006192:Haemophilus Infections / Q000453:epidemiology / Q000517:prevention & control*; D018073:Haemophilus Vaccines / Q000008:administration & dosage; D006801:Humans; D017589:Immunization Programs; D015994:Incidence; D007214:Indonesia / Q000453:epidemiology; D007223:Infant; D008297:Male; D008583:Meningitis, Haemophilus / Q000453:epidemiology / Q000517:prevention & control*; D018410:Pneumonia, Bacterial / Q000453:epidemiology / Q000517:prevention & control*; D011135:Polysaccharides, Bacterial; D013745:Tetanus Toxoid / Q000008:administration & dosage; D018074:Vaccines, Conjugate
D015721:Diphtheria-Tetanus-Pertussis Vaccine; D018073:Haemophilus Vaccines; C055753:Haemophilus influenza type b polysaccharide vaccine-tetanus toxin conjugate; C044237:Haemophilus influenzae type b polysaccharide vaccine; D011135:Polysaccharides, Bacterial; D013745:Tetanus Toxoid; D018074:Vaccines, Conjugate