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Biomedical subjects

D Scheifele

Publications and source records attributed to D Scheifele.

At least 37 records · Page 2Linked to original sources
PubMed1996

Study of booster doses of two Haemophilus influenzae type b conjugate vaccines including their interchangeability.

A prospective, two center study of 319 children was undertaken to assess responses to booster immunization in healthy 18-month-olds who completed primary immunization 12 months earlier with Haemophilus influenzae type b (Hib) conjugate vaccine (either HbOC or PRP-T). Interchangeability of these products as boosters was also assessed, using combination products containing diphtheria, pertussis and tetanus components. The study was randomized and evaluator blinded. Sera obtained prior to booster vaccination and 4 weeks later were tested for anti-PRP using an IgG-specific enzyme immunoassay. Pre-immunization anti-PRP levels were low: unmeasurable levels (< 0.06 microgram ml-1) were present in 47% of those primed with HbOC and 35% of those primed with PRP-T (P < 0.05). Most children responded strongly to booster vaccination. Interchanging the products had no detrimental effect. Children who lacked measurable antibody prior to re-vaccination had significantly weaker responses 4 weeks afterward. Earlier Hib booster vaccination should be considered in Canada to avoid low anti-PRP trough levels. Extended follow-up of antibody levels and vaccine protective efficacy is also advisable given the observed heterogeneity of responses to booster vaccination.

Antibodies↗
PubMed1995

Assessment of a universal, school-based hepatitis B vaccination program.

OBJECTIVE: To assess a hepatitis B vaccination program offered to all grade 6 students in British Columbia in 1992. DESIGN: Cohort study. SETTING: British Columbia, Canada. PARTICIPANTS: All grade 6 students were offered vaccine. Subsets of 454 and 259 students participated in studies of minor adverse events and seroresponse, respectively. INTERVENTION: The vaccine used was Engerix-B, 20 micrograms, given at intervals of 0, 1, and 6 months. MAIN OUTCOME MEASURES: Province-wide acceptance and series completion rates and reports of severe adverse events. Minor adverse events and immunogenicity in subsamples. RESULTS: A total of 127,922 vaccine doses were administered. Initial enrollment totaled 43,358 students or 95.4% of those eligible. The series was completed by 41,594 students (95.6%). Minor adverse events were infrequent in the cohort assessed: no absenteeism or physician visits resulted from vaccination. Sixty-nine reported severe adverse events met surveillance definitions, the major categories being injection site reactions (23% of reports), fainting (20%), and rashes (17%). There was one instance of anaphylaxis. Only 13 of these events resulted in recommendations to discontinue the series. Of students tested following the series, 98% had levels of antibody to hepatitis B surface antigen considered to be protective (> or = 10 IU/L), the geometric mean titer being 690 IU/L (95% confidence interval, 498 to 957 IU/L). CONCLUSION: Our experience indicates that school-based programs for universal vaccination of preadolescents can be highly acceptable and efficient.

Adolescent↗
PubMed1994

Safety and immunogenicity of Haemophilus influenzae vaccine (tetanus toxoid conjugate) administered concurrently or combined with diphtheria and tetanus toxoids, pertussis vaccine and inactivated poliomyelitis vaccine to healthy infants at two, four and six months of age.

The safety and immunogenicity of Haemophilus influenzae vaccine (tetanus toxoid conjugate (PRP-T) administered concurrently in separate sites or mixed in the same syringe with diphtheria and tetanus toxoids, pertussis vaccine and inactivated poliomyelitis vaccine were assessed in 439 infants at 2, 4 and 6 months of age. The proportions with local redness, tenderness and swelling in the separate and combined groups were 18% vs. 11% (P < 0.001), 27% vs. 24% and 15% vs. 13%, respectively. Systemic reactions occurred at similar rates in both groups. The combined vaccine induced tetanus and diphtheria antitoxin titers > or = 0.01 IU/ml in 99.5 and 99.1% of infants, pertussis agglutinin titers > or = 64 in 92.4%, anti-polyribosylribitol phosphate titers > or = 0.15 microgram/ml in 93.8% and > or = 1.0 microgram/ml in 75% and polio-neutralizing titers > or = 8 in > 98% of infants. However, antibody concentrations to PRP-T, some pertussis antigens and tetanus toxoid were significantly lower after combined than after separate injections of DPT/diphtheria and tetanus toxoids, pertussis vaccine and inactivated poliomyelitis vaccine and PRP-T. The clinical significance of these differences is not known, but the interactions observed among the components of the pentavalent vaccine may be of concern because they might influence antibody persistence until the fourth dose is administered.

Diphtheria-Tetanus-Pertussis Vaccine↗
PubMed1994

Immunization of patients with rheumatoid arthritis against influenza: a study of vaccine safety and immunogenicity.

OBJECTIVE: To address the issues of immunogenicity and local and systemic reactions to vaccination with influenza vaccine in patients with rheumatoid arthritis (RA). METHODS: One hundred and twenty-six patients with RA were stratified into 3 groups: (1) those with a history of vaccination with influenza vaccine within 24 months who were receiving usual therapy for RA, (2) those receiving usual therapy for RA but without prior vaccine, and (3) those receiving immunosuppressive medication or prednisone > or = 7.5 mg/day, irrespective of their prior immunization status. Within each group, patients were randomized to receive vaccine or placebo. A group of age matched, healthy controls were also vaccinated. RESULTS: During a one month followup period, adverse reactions occurred with equal frequency among patients with RA and healthy controls. Similar significant increases in titers to the vaccine were seen in all groups of patients with arthritis and in the controls. CONCLUSION: The potential increase in susceptibility to influenza and death from respiratory illness in patients with RA and the demonstrated safety and immunogenicity of influenza vaccine should require the inclusion of patients with RA in standard immunization programs.

Arthritis, Rheumatoid↗
PubMed1993

Can Haemophilus influenzae type b-tetanus toxoid conjugate vaccine be combined with diphtheria toxoid-pertussis vaccine-tetanus toxoid?

OBJECTIVE: To assess the side effects and immune responses after three serial doses of PRP-T vaccine (a Haemophilus influenzae type b [Hib]-tetanus toxoid conjugate vaccine) given concurrently or mixed with adsorbed DPT vaccine (diphtheria toxoid-pertussis vaccine-tetanus toxoid). DESIGN: Multicentre randomized controlled trial. SETTING: Four public health units in western Canada. PARTICIPANTS: Healthy infants 8 to 15 weeks old at entry who were able to receive routine primary vaccinations. Of 444 infants enrolled, 433 (98%) completed the study. INTERVENTIONS: All infants received PRP-T and DPT vaccines at 2, 4 and 6 months of age: half received them mixed in one injection and the others as separate, bilateral injections. MAIN OUTCOME MEASURES: Side-effects 24 and 48 hours after each dose and serologic responses to each vaccine component. RESULTS: Follow-up was obtained after all 1312 vaccinations. Fever was infrequent in the two treatment groups. Local adverse effects of the PRP-T vaccine were infrequent and mild (e.g., redness was noted in 5.9% of cases and the area of redness was more than 2.5 cm in diameter in 0.8%). The incidence rate of local effects of the DPT-containing vaccines was the same in the two groups except for tenderness, which was more frequent in the group given the mixed vaccine (26.6% v. 17.9%, p < 0.001). Serologic data were available for 97% of the subjects. After the three doses 98.1% of the subjects had a PRP antibody level of 0.15 micrograms/mL or more, and 87.9% had a level of 1.0 micrograms/mL or more, both levels compatible with protection against Hib. Responses to PRP-T were comparable between the treatment groups as were responses to the diphtheria and tetanus toxoids. Pertussis agglutinin titres were reduced after administration of one of two PRP-T lots mixed with DPT vaccine, but responses to four other pertussis antigens were not impaired. CONCLUSION: PRP-T vaccine is well tolerated and immunogenic. Combined PRP-T and DPT vaccines performed satisfactorily and may be the preferred method of administration.

Antibodies, Bacterial↗
PubMed1993

Immunogenicity of Haemophilus influenzae type b conjugate vaccine in children with congenital asplenia.

The immunogenicity of Haemophilus influenzae type b polysaccharide-protein conjugate vaccines in congenitally asplenic children is unknown. The short-term immunogenicity of the H. influenzae type b polysaccharide-diphtheria toxoid conjugate vaccine was therefore assessed in 10 children with congenital asplenia by measuring antipolyribosyl-ribitol phosphate antibody titers. An excellent antibody response was seen in 9 children (mean geometric titer in responders after immunization 44.7 micrograms/mL; range, 2.59-402). The remaining child responded to a booster dose. Further studies are required to assess whether H. influenzae type b conjugate vaccines are immunogenic in infancy in the presence of congenital asplenia.

Adolescent↗
PubMed1992

Controlled trial of Haemophilus influenzae type B diphtheria toxoid conjugate combined with diphtheria, tetanus and pertussis vaccines, in 18-month-old children, including comparison of arm versus thigh injection.

A randomized, controlled comparison was made in 175 healthy 18-month-old children given either diphtheria and tetanus toxoids and pertussis vaccine, adsorbed (DTP) and haemophilus b diphtheria toxoid conjugate vaccine (PRP/D) concurrently at separate sites (66 children) or a new vaccine combining these products (109 children). Rates of local or systemic adverse effects postimmunization and antibody responses to each component did not differ significantly between groups. DTP-containing vaccines were better tolerated when given in the thigh than in the arm. The combination DTP-PRP/D vaccine performed satisfactorily at 18 months of age, avoiding the inconvenience of two injections.

Arm↗