Biomedical subjects

Sylvia H Yeh

Publications and source records attributed to Sylvia H Yeh.

6 recordsLinked to original sources

PubMed2006

Shift in the epidemiology of pertussis infection: an indication for pertussis vaccine boosters for adults?

Pertussis vaccination of young children has been effective in reducing the overall disease burden due to Bordetella pertussis in many countries. However, the disease has not been eliminated, although humans are the only known host of this pathogen. In fact, in some countries, the number of reported cases has increased dramatically from their nadir and epidemics routinely occur. In areas where >80% of children <2 years of age have been vaccinated, the burden of disease has shifted from elementary school-aged children (who are presumably protected by vaccination) to young infants (<6 months of age) and individuals >11 years of age. With the recent availability of acellular pertussis vaccines for older children to adults, consideration of a change in current vaccination policy is necessary in order to provide better disease control.

Adolescent↗

PubMed2005

A bovine parainfluenza virus type 3 vaccine is safe and immunogenic in early infancy.

BACKGROUND: A phase 2 trial was conducted to assess in young infants the safety, tolerability, infectivity, and immunogenicity of multiple doses of an intranasal vaccine using bovine parainfluenza virus type 3 (bPIV3). METHODS: One hundred ninety-two healthy 2-month-old infants were randomized 1 : 1 : 1 to receive 1x10(5) median tissue culture infective dose (TCID(50)) bPIV3 vaccine, 1x10(6) TCID(50) bPIV3 vaccine, or placebo at 2, 4, 6, and 12-15 months of age. Safety information was collected by use of diary sheets and telephone interviews. Nasal wash and serum specimens were collected for assessment of infectivity and immunogenicity. RESULTS: The safety profiles of both dosages of bPIV3 were similar to that of placebo, with the exception of fever with temperature of >/=38.1 degrees C after dose 2 only, occurring in 34% of the 1x10(5) TCID(50) group, 35% of the 1x10(6) TCID(50) group, and 12% of the placebo group (P<.01). No vaccine-related serious adverse events were reported. The cumulative vaccine infectivity (isolation of bPIV3 and/or bPIV3 seroconversion) after dose 3 was similar in the 2 vaccine groups (87% in the 1x10(5) TCID(50) group and 77% in the 1x10(6) TCID(50) group) (P=.46). Seroconversion rates after dose 3, assessed by means of hemagglutination inhibition assay, after adjustment for decrease in maternal antibody titers, were 67% in the 1x10(5) TCID(50) group, 57% in the 1x10(6) TCID(50) group, and 12% in the placebo group (P<.01). Isolation of bPIV3 was common after dose 1, dose 2, or dose 3, but only 1 of 51 participants in the vaccine groups had bPIV3 isolated after dose 4. CONCLUSIONS: Multiple doses of bPIV3 vaccine were well tolerated and immunogenic in young infants.

Administration, Intranasal↗

PubMed2005

PEDIARIX: clinical trials.

PEDIARIX is the first pentavalent combination vaccine licensed for use in infants in the USA. This vaccine is indicated for the prevention of diphtheria, tetanus, pertussis, hepatitis B and poliovirus. This article reviews the available data regarding the vaccine's immunogenicity and safety.

Clinical Trials as Topic↗

PubMed2003

Heptavalent pneumococcal vaccine conjugated to outer membrane protein of Neisseria meningitidis serogroup b and nasopharyngeal carriage of Streptococcus pneumoniae in infants.

BACKGROUND: Streptococcus pneumoniae (Sp) is an important bacterial pathogen in children. Nasopharyngeal (NP) colonization of S. pneumoniae is necessary for person-to-person transmission and often precedes invasive disease. METHODS: NP carriage of Sp was studied in 49 infants following administration of a heptavalent pneumococcal conjugate vaccine (PCV) conjugated to the outer membrane protein of serogroup b Neisseria meningitidis (vaccine serotypes: 4, 6B, 9V, 14, 18C, 19F, 23F). The vaccine was administered at 2, 4, 6, and 12 months of age and carriage rates were compared to a concurrent group of 32 infants not given PCV and evaluated over the first 15 months of life. RESULTS: Overall, Sp was isolated in 86/367 (23%) of NP cultures and 49% of infants. Serotype 23F was significantly less prevalent in the PCV group (1.9%) than the control group (16.1%) (P<0.05). Analysis of the proportion of children with prevalent carriage or acquisition of carriage did not differ between groups when evaluated by age or serotype. We noted, however, decreased acquisition and carriage in the vaccine group 1 month following the 12 month dose of PCV for vaccine serotypes (76 and 52% reduction, respectively), but this did not reach statistical significance (P=0.3). Adjustment for age, daycare and antibiotic use by multivariate modeling revealed no difference in carriage of vaccine containing serotypes or non-vaccine serotypes between groups. CONCLUSION: We did not show a significant effect of this heptavalent PCV on NP carriage. Further study of this issue, including a larger population size, is needed.

Bacterial Outer Membrane Proteins↗

PubMed2003

Pertussis: persistent pathogen, imperfect vaccines.

Routine use of pertussis vaccines has diminished the incidence of this disease but has not eliminated the pathogen. Pertussis remains a significant cause of disease in both very young infants and in the adolescent and adult populations. Acellular pertussis vaccines have fewer adverse reactions compared with whole-cell pertussis vaccines. Although efficacious against severe disease, current vaccines may not be as efficacious against milder forms of infection. New methodologies for understanding disease pathogenesis, immune responses and vaccine development are needed to effectively interrupt continued transmission of this pathogen.

Adolescent↗

PubMed2003

Clinical evaluation of a DTaP-HepB-IPV combined vaccine.

OBJECTIVE: To provide an overview of prelicensure clinical data for a new pediatric vaccine that combines diphtheria, tetanus, acellular pertussis, hepatitis B, and inactivated poliovirus vaccines into a single injection (DTaP-HepB-IPV combined vaccine; Pediarix, GlaxoSmithKline Biologicals, Rixensart, Belgium). METHODS: The safety and immunogenicity of DTaP-HepB-IPV combined vaccine have been evaluated extensively in clinical trials in infants. To date, DTaP-HepB-IPV combined vaccine has been administered to more than 7,000 infants as a 3-dose primary series during the first year of life. RESULTS: Studies show that DTaP-HepB-IPV combined vaccine is generally safe, well tolerated, and has not caused any significant serious adverse events. The rates of solicited and unsolicited reports of adverse reactions following vaccination were similar between groups receiving DTaP-HepB-IPV combined vaccine and comparator groups receiving the vaccine components separately. DTaP-HepB-IPV combined vaccine induces immunogenicity (as measured by seroprotection or vaccine response rates to each of the vaccine components [diphtheria, tetanus, 3 pertussis antigens, hepatitis B, and poliovirus types 1, 2, and 31) similar to licensed vaccine components administered separately. CONCLUSION: In prelicensure clinical studies, DTaP-HepB-IPV combined vaccine was safe and immunogenic when given to infants as a primary 3-dose series. As a single injection of multiple vaccine components, DTaP-HepB-IPV combined vaccine may provide a safe and effective alternative to the current multiple-injection immunization regimen.

Diphtheria-Tetanus-acellular Pertussis Vaccines↗