Vacuna anti-Haemophilus influenzae de tipo b (Hib) en el Calendario Nacional de Argentina: portación nasofaríngea de Hib tras 8 años de su introducción
ABSTRACT Introduction: As a part of the PAHO supported protocol "Evaluation of the impact of Haemophilus influenzae b vaccination programs in four Latinamerican countrys", a study took place in Argentine 8 years after introduction of Hib vaccine. Objective: To evalúate the impact of Hib vaccination measuring Nasopharyngeal Colonization (NC) rate and to identify factors associated to Haemophilus influenzae (HI) carrier status. Methods: Cross-sectional study -from June 27* 2005 to April 12* 2006- in two pediatric hospitals, HNRG and PE. Nasopharyngeal swab specimens were processed in the INEI-ANLIS "Dr. C. Malbrán"; samples were cultured in chocolate agar médium containing bacitracin. Hi was identified with technics of Gram, oxidase, catalase, growth factors (V-X-XV) and test of porphyrin. Capsular serotypification was made by agglutination in lamina with specific antisera and the confirmation by polymerase chain reaction. Population: 900 children of 1 year of age, vaccinated with 3 doses and 700 children of 5 years, with 4 vaccine doses. Results: Hi was detected in 40% (641/1.600) of samples, among Hi, 4,8% (31/641) were encapsulated (3 serotypes a, 1 b, 3 c, 5 d, 7 e, and 12 f). Only one child of 1 year was NC carrier of Hi type b (0.06%).Conclusions: We found a very low NC Hib (0.06%) rate, for this reason associations could not be analyzed. The age, household and day care center contacts were associated with NC by Haemophilus influenzae.
SourceAvailable from: Miguel Sánchez-Alemán[Show abstract] [Hide abstract]
ABSTRACT: We determined the seroprevalence of protective antibodies against Hib in Mexican children under the age of five using a standardized enzyme-linked immunosorbent assay. Hib antibodies (≥ 0.15 μg/ml) were present in 95.34% (±1.14% [seroprevalence ± standard error]) of samples. Fewer children aged 30 to 47 months had protective Hib antibody levels (91.45% ± 2.60%) than children from 12 to 29 and 48 to 59 months (97.3% ± 1.34% and 97.44% ± 1.80%, respectively).Clinical and vaccine Immunology: CVI 10/2010; 17(10):1639-41. DOI:10.1128/CVI.00249-10 · 2.37 Impact Factor