[Pediatric surveillance of invasive infections caused by Haemophilus influenzae type b in children in the period following introduction of vaccination].
OBJECTIVE
Evaluation of the effect of vaccination against Haemophilus influenzae type b (Hib) on the occurrence of invasive Hib infections in children since its introduction into the national immunization programme in April 1993.


METHODS
Observational study.


METHODS
Nationwide investigation.


METHODS
Data collected through active surveillance of invasive Hib infections by paediatricians for the period from October 1993 to September 1994 (11 months) were compared with data from the meningitis surveillance by the Netherlands Reference Laboratory for Bacterial Meningitis.


RESULTS
A total of 139 paediatric reports of invasive disease by H. influenzae concerned 57 cases of only meningitis, 35 of meningitis with sepsis, 2 of meningitis with arthritis, one of meningitis with arthritis and osteomyelitis, 34 of epiglottitis including one case with sepsis, 8 of only sepsis and 2 of only arthritis. All proven infections by Hib occurred in children who had not or incompletely been vaccinated. One child with sepsis had had three vaccinations and became ill five months later; the isolated bacterial strain was not serotyped. Typing was performed in only 80% of the isolates, of which 98% were of type b. Appropriate culturing and typing was often omitted in case of epiglottitis.


CONCLUSIONS
The effect of vaccination against Hib became apparent in a small number of cases of invasive Hib disease reported by paediatricians; the peak incidence of meningitis no longer occurred in children under one year of age but in children aged one year. The paediatric surveillance described offers possibilities for monitoring Hib epidemiology.
Conyn-van Spaendonck
M A
MA
Rijksinstituut voor Volksgezondheid en Milieuhygiëne, Centrum voor Infectieziekten Epidemiologie, Bilthoven.
Suijkerbuijk
A W
AW
Hirasing
R A
RA
van Pelt
W
W
D002648:Child; D002675:Child, Preschool; D004826:Epiglottitis / Q000382:microbiology; D006192:Haemophilus Infections / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D018073:Haemophilus Vaccines; D006193:Haemophilus influenzae; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008583:Meningitis, Haemophilus / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control; D009426:Netherlands / Q000453:epidemiology; D011159:Population Surveillance; D012042:Registries
D018073:Haemophilus Vaccines
Pediatrische surveillance van invasieve infecties door Haemophilus influenzae type b bij kinderen in de periode na introductie van de vaccinatie.