Avidity maturation of antibody to Haemophilus influenzae type b (Hib) after immunization with diphtheria-tetanus-acellular pertussis-hib-hepatitis B combined vaccine in infants. (17/1003)

Antibody avidity to Haemophilus influenzae type b (Hib) polysaccharide (PS) was assessed in infants vaccinated with diphtheria-tetanus-acellular pertussis (DTaP) combined with Hib-PS conjugated to tetanus toxoid (PRP-T) and hepatitis B (HB) (DTaP-PRP-T-HB) and after a PRP-conjugate (CRM197-OS) booster 3-7 months later. Avidity differed between infants with anti-Hib-PS IgG antibody <1 or >1 microg/mL postprimary series (avidity index [AI], 42%, 95% confidence interval [CI], 35%-49%, and 68% and 63%-72%, respectively; P<.0001). For infants with <1 microgram/mL anti-Hib-PS IgG antibody, mean AI rose by the time of preboost immunization to 61% (95% CI, 57%-65%), even though total IgG antibody levels fell. Spontaneous Hib-PS antibody rises after primary series DTaP-PRP-T-HB vaccination were followed by high postboost anti-Hib-PS IgG antibody levels and avidity. The DTaP-PRP-T-HB combination vaccine studied elicits high avidity antibody, and affinity maturation appears to occur in the absence of further antigen exposure even in those with very low anti-Hib-PS antibody.  (+info)

A plant-derived edible vaccine against hepatitis B virus. (18/1003)

The infectious hepatitis B virus represents 42 nm spherical double-shelled particles. However, analysis of blood from hepatitis B virus carriers revealed the presence of smaller 22 nm particles consisting of a viral envelope surface protein. These particles are highly immunogenic and have been used in the design of hepatitis B virus vaccine produced in yeast. Upon expression in yeast, these proteins form virus-like particles that are used for parenteral immunization. Therefore, the DNA fragment encoding hepatitis B virus surface antigen was introduced into Agrobacterium tumerifacience LBA4404 and used to obtain transgenic lupin (Lupinus luteus L.) and lettuce (Lactuca sativa L.) cv. Burpee Bibb expressing envelope surface protein. Mice that were fed the transgenic lupin tissue developed significant levels of hepatitis B virus-specific antibodies. Human volunteers, fed with transgenic lettuce plants expressing hepatitis B virus surface antigen, developed specific serum-IgG response to plant produced protein.  (+info)

Unexplained fever in neonates may be associated with hepatitis B vaccine. (19/1003)

AIM: To investigate whether hepatitis B vaccination has increased the number of cases of unexplained neonatal fever. METHOD: The files of all infants born from 1 January 1991 to 31 December 1992, in whom a diagnosis of "injected antibiotic" or "disease of temperature regulation" was recorded, were reviewed. Those who had unexplained fever of 38 degrees C or higher during the first three days of life were divided into two groups: infants who did not receive the hepatitis B vaccine (1991) and infants who did (1992). RESULTS: In 1992 the incidence of unexplained fever in hepatitis B vaccinated neonates was significantly higher than in the 1991 group of pre-vaccination neonates (35 out of 5819 (0.6%) vs 14 out of 5010 neonates (0.28%) respectively, p=0.013). CONCLUSIONS: The increase in the number of cases of unexplained neonatal fever seems to be associated with the introduction of routine hepatitis B vaccination on the first day of life. The possibility that an excess number of neonates will undergo unnecessary procedures and treatment to diagnose unexplained fever justifies planning a controlled study to determine whether these preliminary findings point to a significant problem.  (+info)

Lack of association between early childhood immunizations and beta-cell autoimmunity. (20/1003)

OBJECTIVE: To determine whether early childhood immunization history affects the risk of developing the beta-cell autoimmunity that precedes type 1 diabetes. RESEARCH DESIGN AND METHODS: This article describes a case-control study whose participants were 317 children aged < or = 12 years who have a first-degree relative with type 1 diabetes. The children were enrolled in a prospective cohort study of the etiology of beta-cell autoimmunity, the Diabetes Autoimmunity Study in the Young, in Denver, Colorado. The main outcome measure was beta-cell autoimmunity as determined by persistent autoantibodies against insulin, GAD, or islet cell antibody (IA-2) 512. The number of cases with beta-cell autoimmunity was 25, and the number of control subjects (the remainder of the cohort) was 292. RESULTS: There was no difference between cases and control subjects in the proportion receiving hepatitis B (HBV), Haemophilus influenzae b (Hib), polio, or diphtheria tetanus pertussis (DTP) vaccines before 9 months of age; in the proportion receiving HBV at birth rather than later; or in the median age at first HBV, Hib, polio, or DTP vaccination. CONCLUSIONS: The results suggest that changing the early childhood immunization schedule would not affect the risk of developing beta-cell autoimmunity or type 1 diabetes.  (+info)

Rheumatic disorders developed after hepatitis B vaccination. (21/1003)

OBJECTIVE: To obtain an overview of rheumatic disorders occurring after hepatitis B vaccination. METHODS: A questionnaire was sent to rheumatology departments in nine French hospitals. Criteria for entry were rheumatic complaints of 1 week's duration or more, occurrence during the 2 months following hepatitis B vaccination, no previously diagnosed rheumatic disease and no other explanation for the complaints. RESULTS: Twenty-two patients were included. The observed disorders were as follows: rheumatoid arthritis for six patients; exacerbation of a previously non-diagnosed systemic lupus erythematosus for two; post-vaccinal arthritis for five; polyarthralgia-myalgia for four; suspected or biopsy-proved vasculitis for three; miscellaneous for two. CONCLUSIONS: Hepatitis B vaccine might be followed by various rheumatic conditions and might trigger the onset of underlying inflammatory or autoimmune rheumatic diseases. However, a causal relationship between hepatitis B vaccination and the observed rheumatic manifestations cannot be easily established. Further epidemiological studies are needed to establish whether hepatitis B vaccination is associated or not with an incidence of rheumatic disorders higher than normal.  (+info)

Comparison and characterization of immunoglobulin G subclasses among primate species. (22/1003)

Little information is available on the immunoglobulin G (IgG) subclasses expressed in the sera of nonhuman primate species. To address this issue, we compared the IgG subclasses found in humans (IgG1, IgG2, IgG3, and IgG4) to those of nonhuman primates, such as baboons and macaques. Cross-reactive antihuman IgG subtype-specific reagents were identified and used to analyze purified IgG from sera by solid-phase enzyme-linked immunosorbent assay. Protein A-purified human IgG obtained from sera was composed of IgG1, IgG2, IgG3, and IgG4, whereas baboon and macaque IgG was composed of IgG1, IgG2, and IgG4. Protein G-purified human IgG was composed of IgG1, IgG2, IgG3, and IgG4, whereas baboon and macaque IgG was composed of IgG1, IgG2, and IgG4. To test the possibility that baboon and macaque IgG3 is actually present, but is outcompeted for binding to proteins A and G by the other more abundant IgG subclasses, we repurified the IgG from sera that did not bind either protein A or protein G. We found a baboon IgG3 population in the sera that did not bind protein A, but bound protein G. No IgG3 subtype was detectable in macaque sera. These data suggest that baboon sera, like human sera, contain four IgG subtypes, whereas macaque sera exhibit only three of the human subclass analogs. In addition, the IgG subtype-specific reagents were shown to be useful in determining the IgG subclass distribution following vaccination of baboons with hepatitis B surface antigen.  (+info)

Progress in coverage with hepatitis B vaccine among US children, 1994-1997. (23/1003)

OBJECTIVES: This study was done to assess progress in hepatitis B vaccination of children from 1994 through 1997. METHODS: We used data from the National Immunization Survey (NIS), a random-digit-dialed telephone survey that includes a mail survey to verify vaccination providers' records. The NIS is conducted in 78 geographic areas (50 states and 28 selected urban areas) in the United States. RESULTS: A total of 32,433 household interviews were completed in the 1997 NIS. An estimated 83.7% of children aged 19 to 35 months received 3 or more doses of hepatitis B vaccine. Coverage with 3 doses was greater (86.7%) among children in states that had day care entry requirements for hepatitis B vaccination than among children in states without such requirements (83.0%) and was greater among children from families with incomes at or above the poverty level (85.0%) than among children below the poverty level (80.6%). Hepatitis B vaccination of children increased from 1994 through 1996, from 41% to 84%, but coverage reached a constant level of 84% to 85% in 1996/97. CONCLUSION: Although substantial progress has been made in fully vaccinating children against hepatitis B, greater efforts are needed to ensure that all infants receive 3 doses of hepatitis B vaccine.  (+info)

The Denver school-based adolescent hepatitis B vaccination program: a cost analysis with risk simulation. (24/1003)

OBJECTIVES: This study sought to compare the cost-effectiveness of a school-based hepatitis B vaccine delivery program with that of a vaccine delivery program associated with a network health maintenance organization (HMO). METHODS: The vaccination program enrolled 3359 sixth-grade students from 18 middle schools in Denver, Colo. Immunization status and direct and indirect program costs were compiled. The sensitivity of the outcomes was assessed by simulation methods. RESULTS: The per-dose cost-effectiveness ratio for the school-based delivery system was $31. This cost-effectiveness ratio remained stable when the model was simulated with costs that were underestimated or overestimated by 20%. In the network HMO, the direct cost per dose was $68 and the societal cost was $118 when the child's father worked full-time and the mother worked part-time. There is less than a 5% chance that the network HMO-based vaccination program could be more cost-effective than the school-based program. CONCLUSIONS: The cost per dose of the school-based program was significantly less than that of the network HMO-based program, because in the school program government-purchased vaccine was available at a lower cost and parents did not incur work-loss costs.  (+info)