34 Haemophilus influenzae type b (Hib) strains isolated from cerebrospinal fluids (CSFs) of meningitis patients at National Hospital of Pediatrics, Hanoi, between 11/2002 and 12/2003 were biotyped, serotyped and analyzed by using PCR with specific primers, Pulsed field gel electrophoresis (PFGE) with Smal restriction enzyme. The results showed that 24 of 34 Hib strains (70.6%) belong to biotype II; 8 of 34 (23.5%) belong to biotype I. PCR patterns with capsular polysaccharide type b specified primers of the 34 Hib strains were identical. DNA restriction patterns generated by PFGE (so-called PFGE patterns) of the 34 Hib strains were mainly distributed into 2 PFGE patterns. DNA restriction patterns had close relationship to biotype. The presence of PFGE patterns of Hib strains was not related to season
Haemophilus influenzae type b ; pathogenicity ; Haemophilus influenzae

No abstract available.
Extremities* ; Gangrene* ; Haemophilus influenzae type b* ; Haemophilus influenzae* ; Haemophilus*

A survey conducted from 1-2/2000 in the 7 urban districts of Hanoi, Vietnam showed that overall use rate for Hib vaccine among children under 5 year of age was 3.2% and coverage for meningoccoal vaccine was 1.4%.
Vaccines ; Haemophilus influenzae type b

Haemophilus influenzae type b(Hib) is one of the most common cause of invasive bacterial disease in children. In Korea, However, the proportion occupied by Hib as a cause of pediatric pathogen is less compared to those of western countries. Natural immunity to Haemophilus influenzae type b was determined on 308 Korean children. The titration of antibody to capsular polysaccharide (PRP) was performed by the radioantigen binding assay. Forty percent of the total subjects and 31% of children under 5 years had an antibody level considered to be protective( 0.15 g/ml).Seropositivity was 13.6% in 12~17 month age group, and increased progressively to 19% in 5~10 year age group. In the age groups under 36 months of age, the geometric mean titers of anti-PRP antibody were below the protective level. These data indicate that a lot of Korean children under 5 years of age do not have antibody levels considered to be protective against H. influenzae type b, and do not explain the apparent low risk of Korean children to Hib Further studies including comparative antibody response to polysa-charide and protein antigens with other racial groups are needed.
Antibody Formation ; Child* ; Haemophilus influenzae type b* ; Haemophilus influenzae* ; Haemophilus* ; Humans ; Immunity, Innate ; Influenza, Human ; Korea

China ; Haemophilus Infections ; Haemophilus influenzae type b ; Humans ; Research ; trends

The ribose and phosphorus contents in Haemophilus influenzae type b (Hib) capsular polysaccharide (CPS) are two important chemical indexes for the development and quality control of Hib conjugate vaccine. A quantitative ¹H- and ³¹P-NMR method using a single internal standard was developed for simultaneous determination of ribose and phosphorus contents in Hib CPS. Hexamethylphosphoramide (HMPA) was successfully utilized as an internal standard in quantitative ¹H-NMR method for ribose content determination. The ribose and phosphorus contents were found to be affected by the concentration of polysaccharide solution. Thus, 15-20 mg·L^-1 was the optimal concentration range of Hib CPS in D₂O solution for determination of ribose and phosphorus contents by this method. The ribose and phosphorus contents obtained by the quantitative NMR were consistent with those obtained by traditional chemical methods. In conclusion, this quantitative ¹H- and ³¹P-NMR method using a single internal standard shows good specificity, accuracy and precision, providing a valuable approach for the quality control of Hib glycoconjugate vaccines.
Haemophilus Vaccines ; Haemophilus influenzae type b ; Phosphorus ; Polysaccharides, Bacterial ; Ribose

Haemophilus influenzae is one of the main pathogens of encephalitis in children less than 5 years old. The rate of ampicillin resistant strain is not high. No beta-lactamase-producing and ampicillin-resistant (BLNAR) isolates were found. The PFGE patterns of Hib isolates were highly divergent, but most could be classified into three groups (A, B and C). Hib isolates from the CSF of patients and from nasopharynges of household contacts showed the same PFGE patterns. This observation suggested that household contacts of patients are a possible reservoir of Hib.
Haemophilus influenzae type b ; Orf virus ; Diagnosis

Seventy-nice pediatric patient - family pairs were detected for Hib or Hib-antigen. The study also examined 22 pairs of H. influenzae strains isolated from CSF of patients and from upper respiratory tract of the family members of the patients to determine serotype, biotype, presence of Beta-lactamase, PCR with Hib-specified primers, and PFGE with SmaI restriction enzyme. The results showed that 44.4% of the patients` families had Hib carriers; all of 22 H. influenzae isolated pairs from patients and their families had serotype b; 17 of 22 pairs had characteristics of biotype II; 16 of 22 pairs had Beta-lactamase; and 9 of 22 pairs had both the PCR pattern and PFGE pattern. Close contact with Hib carriers was a factor of Hib meningitis contagiousness in children under 5 years of age
Family ; Haemophilus influenzae type b ; Meningitis ; child

Among the fifty-three clinical isolates of Haemophilus influenzae, nineteen isolates including eight isolates of each biotype I-VIII, six of serotype b (Hib) strains and five of nontypeable strains were characterized by SDS-PAGE about outer membrane protein (OMP), restriction enzyme analysis (REA) and rRNA gene restriction pattems. OMP patterns showed to common band patterns in each H. influenzae isolate. Based on the two major proteins, 31KDa-38KDa, isolated strains were classified into 7 subtypes. In the OMP patterns about biotype and serotype, the specific pattern of each biotype was not distinguishable, but all of the serotype b strains were shown identical unique pattern, therefore it made distinctive difference with nontypeable strains. The digested genomic DNAs with EcoRI were identical result with rRNA gene restriction. It was more subdivided into 10 ribotypes. The most common ribotype I and serotype 1 accounted for 6 strains (31.6%) and 7 strains (36.8%) of the 19 clinical isolates, respectively. Hib isolates that were both OMP subtype 1 and ribotype I accounted for 2 strains (10.5%). In the epidemiologically unrelated strains, the putative association between the subtypes could not be confirmed. According to these results, the three methods were discriminatory and appropriate techniques for epidemiological studies of H. influenzae.
DNA ; Electrophoresis, Polyacrylamide Gel* ; Genes, rRNA* ; Haemophilus influenzae type b ; Haemophilus influenzae* ; Haemophilus* ; Influenza, Human ; Membrane Proteins ; Restriction Mapping* ; Ribotyping

PURPOSE: This study was conducted to validate enzyme immunoassay (EIA) for the quantitative measurement of human IgG antibodies specific for Haemophilus influenzae type b (Hib) capsular polysaccharide. METHOD: We evaluated specificity, repeatability, intermediate precision, accuracy, lower limit of quantification (LLOQ), and stability to validate standardized EIA for the quantitative measurement of human anti-polyribosylribitol phosphate (PRP) IgG antibodies. RESULTS: The results indicated that this EIA showed specificity to HbO-HA antigen and repeatability and intermediate precision were within acceptance criteria (repeatability: CV < or =15%, intermediate precision: CV < or =20%). The EIA-derived results from this laboratory were equivalent to those obtained by the standard radioactive antigen binding assay (RABA) for quantitation of anti-PRP antibodies in the 28 sera. Spiking recovery result was within acceptance criteria (100+/-20%). The precision and accuracy of samples in LLOQ were from -14.7 to -4.7% in nominal values, which were within acceptance criteria (precision: CV < or =25%, accuracy: +/-25%). Freeze-thaw stability and short term temperature stability were within +/-20% of acceptance criteria. CONCLUSIONS: The EIA which is performed at the Center for Vaccine Evaluation and Study Ewha Medical Research Institute, is an appropriate serologic assay which can be used for quantitation of anti-PRP IgG antibodies in human sera.
Academies and Institutes ; Antibodies* ; Haemophilus influenzae type b* ; Haemophilus influenzae* ; Haemophilus* ; Humans* ; Immunoenzyme Techniques* ; Immunoglobulin G* ; Sensitivity and Specificity