The impact of Haemophilus influenzae type b vaccination in Sweden.
The number of patients with meningitis and bacteremia due to Haemophilus influenzae was studied in Sweden over the period 1987-1994. Conjugated H. influenzae type b vaccines were introduced in Sweden in 1992, and all children born after December 31, 1992, were offered vaccination free of charge. A rapid decline of H. influenzae meningitis and bacteraemia was observed in the autumn of 1993, when the expected peak incidence failed to appear. In the prevaccination period 1987-1991, the average annual incidence (cases/100,000) was 34.4 in children aged 0-4 years. In 1994, the annual incidence fell to 3.5. No significant decline was observed in older children or adults. There was a 92% reduction in the number of meningitis cases and an 83% reduction in cases of bacteraemia. A similar decline was noted in 2 regions which followed different strategies for the introduction of the vaccination programme.
Garpenholt
O
O
Department of Clinical Microbiology, Orebro Medical Centre Hospital, Sweden.
Silfverdal
S A
SA
Hugosson
S
S
Fredlund
H
H
Bodin
L
L
Romanus
V
V
Olcén
P
P
D000328:Adult; D016470:Bacteremia / Q000453:epidemiology / Q000517:prevention & control*; D016667:Bacterial Capsules; D002675:Child, Preschool; D006192:Haemophilus Infections / Q000453:epidemiology / Q000517:prevention & control*; D018073:Haemophilus Vaccines / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D017589:Immunization Programs / Q000639:trends; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D016014:Linear Models; D008583:Meningitis, Haemophilus / Q000453:epidemiology / Q000517:prevention & control*; D011135:Polysaccharides, Bacterial / Q000008:administration & dosage* / Q000009:adverse effects; D013548:Sweden / Q000453:epidemiology
D018073:Haemophilus Vaccines; C044237:Haemophilus influenzae type b polysaccharide vaccine; D011135:Polysaccharides, Bacterial