Decreased point prevalence of Haemophilus influenzae type b (Hib) oropharyngeal colonization by mass immunization of brazilian children less than 5 years old with Hib polyribosylribitol phosphate polysaccharide-tetanus toxoid conjugate vaccine in combination with diphtheria-tetanus toxoids-pertussis vaccine.
A protective herd effect has been described after susceptible populations of children are vaccinated with conjugate Haemophilus influenzae type b (Hib).
Hib carriage was studied in children aged 6-24 months attending day care centers in two cities in southern Brazil (Curitiba and Porto Alegre).
In Curitiba, routine immunization with Hib polyribosylribitol phosphate polysaccharide-tetanus toxoid conjugate vaccine (PRP-T) in combination with diphtheria-tetanus toxoids-pertussis vaccine (PRP-T/DTP) has been offered since September 1996 ; DTP vaccine alone is routinely given in Porto Alegre.
Children in Porto Alegre (n=643) were 8 times less likely to have received adequate Hib vaccination and 4 times more likely to be Hib carriers than children in Curitiba (n=647 ; i.e., point prevalence of oropharyngeal colonization, 4.8% vs. 1.2%). Point prevalence of carriage with non-type b or other nontypeable Hi was similar in children of both cities.
There was a vaccination effect on carriage rates in children who received a primary 3-dose series, independent of the booster dose, suggesting that a booster may be unnecessary to induce population protection.
Mots-clés Pascal : Haemophilus influenzae, Pasteurellaceae, Bactérie, Enfant, Homme, Garderie enfant, Epidémiologie, Vaccination, Prévalence, Immunoprotection, Vaccin associé, Diphtérie, Bactériose, Infection, Tétanos, Anatoxine, Coqueluche, Toxine, Brésil, Amérique du Sud, Amérique
Mots-clés Pascal anglais : Haemophilus influenzae, Pasteurellaceae, Bacteria, Child, Human, Day care center, Epidemiology, Vaccination, Prevalence, Immunoprotection, Mixed vaccine, Diphtheria, Bacteriosis, Infection, Tetanus, Toxoid, Whooping cough, Toxin, Brazil, South America, America
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 99-0492141
Code Inist : 002A05B12. Création : 22/03/2000.