Post-vaccination Levels Research Articles

Four-year follow-up of the immune status of young adults given a single booster dose of trivalent oral poliovaccine.

In 1988 an outbreak of type 1 paralytic poliomyelitis occurred in Israel. Almost the entire population in the age group 0-40 years received a single dose of trivalent oral polio vaccine. We examined the serological responses to the vaccine at 2 weeks and 4 years later, in a group of 17 vaccines. Geometric mean antibody titres (GMTs) against both the type 1 epidemic and Mahoney strains had declined by about 50% from the levels found at 2 weeks after vaccination. However, they were still more than five times higher than the prevaccination levels. All vaccines had neutralizing antibody titres against both the type 1 strains of at least 1:64, well above the 1:8 titre regarded as protective. The GMTs against the type 2 and 3 strains declined to about one-third of the 2-week postvaccination levels but were also well above protective levels. These findings indicate that antibody titres against both the Mahoney and epidemic type 1 strains remained at very adequate levels over a period of at least 4 years. Thus the immunity resulting from a single booster dose of oral poliovaccine in young adults is likely to be long-lasting, a finding of particular importance for travellers on extended visits to endemic areas.

Antibody to capsular polysaccharides of Streptococcus pneumoniae: prevalence, persistence, and response to revaccination.

The prevalence of immunity to Streptococcus pneumoniae in the adult population of the United States is unknown. In the study described herein, military recruits had anticapsular IgG antibody to only 15% of common pneumococcal serotypes, whereas working men and elderly men had IgG antibody to 33% and 34% of the common serotypes, respectively (P < .001). Among eight elderly subjects, the prevalence of IgG antibody to capsular polysaccharides increased from 30% to 78% after pneumococcal vaccination; 6 years thereafter, the rate of positive reactions had declined to 58% and IgG levels had declined substantially. With revaccination, IgG levels returned to within (+/-) 40% of the original postvaccination levels. IgM and IgG antibody appeared or began to increase in titer 6 days after vaccination; the rate and degree of response were the same after the first and second exposures. Since most individuals rapidly develop IgG antibody after colonization by S. pneumoniae and since IgG confers immunity, these data suggest that pneumonia is infrequent among healthy adults not because preexisting immunity is widespread but because--with colonization--an immune response develops rapidly, preceding specific events that might lead to infection. Our findings support recommended vaccination procedures and suggest that wider application in subsets of healthy younger adults should be considered.

Safety and Immunogenicity of Haemophilus influenzae Type b Oligosaccharide-CRM197 Conjugate Vaccine in Infants Aged 15 to 23 Months

A total of 268 infants aged 15 to 23 months received one dose of a vaccine composed of Haemophilus influenzae type b oligosaccharides covalently linked to the nontoxic diphtheria toxin variant CRM197 (HbOC; HibTITER). Side effects associated with vaccination were infrequent, transient, and mild. One month after a single vaccination, the anti-H influenzae type b capsular polysaccharide antibody concentration rose from a geometric mean prevaccination level of 0.20 microgram/mL to 13.77 micrograms/mL. Of these infants, 99% had a postvaccination level greater than or equal to 1.00 microgram/mL, a level associated with long-term protection. The immune response was long-lived: all of the children who were monitored 17 to 27 months after vaccination had concentrations greater than or equal to 1.00 microgram/mL. The anti-H influenzae type b capsular polysaccharide antibody generated was predominantly of the IgG isotype and IgG1 subclass. The immune sera had bactericidal activity in vitro and conferred passive protection in the infant rat meningitis model.

Immunogenicity of Haemophilus influenzae Type B Vaccines in Children with Hepatoportoenterostomies

To assess the immunogenicity of HIB vaccines in patients in whom hepatoportoenterostomies were performed for biliary atresia, eight such children received Haemophilus influenzae type b-polyribosylribitol phosphate (HIB-PRP) vaccine and had pre- and postvaccination total serum anti-PRP antibody concentrations determined by radioimmunoassay. Preimmunization anti-PRP antibody levels ranged from less than 0.125 to 0.40 microgram/ml [geometric mean antibody titer (GMT) 0.106 microgram/ml], while postvaccination levels ranged from 0.161 to 1.192 micrograms/ml (GMT = 0.489 microgram/ml). Five children who did not achieve postimmunization anti-PRP antibody levels greater than 1.0 microgram/ml received 15 micrograms of either PRP coupled to diphtheria toxoid (PRP-D) or PRP coupled to an outer membrane protein complex of Neisseria meningitidis group B (PRP-NOMP) conjugate vaccine. Anti-PRP antibody levels 1 month after immunization with HIB conjugate vaccines ranged from 1.51 to 10.35 micrograms/ml (GMT = 3.386 micrograms/ml). Patients with extrahepatic biliary atresia and hepatoportoenterostomies who previously received the HIB-PRP vaccine should be revaccinated with PRP protein conjugate vaccines to ensure adequate protection against H. influenzae type b disease.

Immunogenicity of Haemophilus influenzae Type B Vaccines in Children with Hepatoportoenterostomies

Summary:To assess the immunogenicity of HIB vaccines in patients in whom hepatoportoenterostomies were performed for biliary atresia, eight such children received Haemophilus influenzae type b‐polyribosylribitol phosphate (HIB‐PRP) vaccine and had pre‐ and postvaccination total serum anti‐PRP antibody concentrations determined by radioimmunoassay. Preimmunization anti‐PRP antibody levels ranged from &lt;0.125 to 0.40 μg/ml [geometric mean antibody titer (GMT) 0.106 μg/ml], while postvaccination levels ranged from 0.161 to 1.192 μg/ml (GMT = 0.489 μg/ml). Five children who did not achieve postimmunization anti‐PRP antibody levels &gt;1.0 μg/ml received 15 μg of either PRP coupled to diphtheria toxoid (PRP‐D) or PRP coupled to an outer membrane protein complex of Neisseria meningitidis group B (PRP‐NOMP) conjugate vaccine. Anti‐PRP antibody levels 1 month after immunization with HIB conjugate vaccines ranged from 1.51 to 10.35 μg/ml (GMT = 3.386 μg/ml). Patients with extrahepatic biliary atresia and hepatoportoenterostomies who previously received the HIB‐PRP vaccine should be revaccinated with PRP protein conjugate vaccines to ensure adequate protection against H. influenzae type b disease.

Serologic Responses to an Haemophilus influenzae Type b Polysaccharide-Neisseria meningitidis Outer Membrane Protein Conjugate Vaccine in Very Young Gambian Infants

Recent studies in the United States and Europe have shown that Haemophilus influenzae type b polysaccharide-protein conjugate vaccines can induce protective antibody levels in young infants, but it was not clear that this would be the case in African infants, to whom H influenzae vaccines must be given at a very early age to prevent disease caused by H influenzae. Therefore, antibody responses to an H influenzae type b polysaccharide-Neisseria meningitidis outer membrane protein conjugate vaccine were measured in very young Gambian infants. In the first group (n = 85), to whom the vaccine was given at the ages of 1 and 3 months, the geometric mean antibody level rose from a prevaccination level of 0.23 microgram/mL to a postvaccination level of 1.27 micrograms/mL, and in the second group (n = 56), vaccinated at the ages of 2 and 4 months, the prevaccination level of 0.16 microgram/mL rose to a postvaccination level of 1.59 micrograms/mL. These two final postvaccination levels did not differ significantly, and interpolation suggests that similar antibody levels were present in both groups of infants at the age of 3 months. This is the age by which protection would need to be achieved to protect against H influenzae meningitis in The Gambia and in other countries where the infection has similar epidemiologic characteristics. No significant side effects of vaccination were noted.

α 2-Macroglobulin and fibrinogen modulate inflammatory edema in man

Animal experiments suggest that the response of acute-phase proteins (APPs) modulates the inflammatory reaction following tissue injury. To study this in man we investigated the relation between a number of APPs, including fibrinogen and alpha 2-macroglobulin, and the inflammatory edema induced by a primary immunization against cholera, typhoid, and yellow fever. Vaccination induces a significant APP response; however, only alpha 2-macroglobulin and fibrinogen were of importance to the amount of edema, measured 24 h after vaccination. High plasma levels of alpha 2-macroglobulin strongly inhibit the amount of edema, whereas a high level of fibrinogen proved to be a stimulating factor. This holds both for the basal prevaccination levels and the postvaccination levels. The normal variation of the plasma concentration of these proteins in healthy subjects seems to be a determining factor to the amount of edema in this kind of injury.

HALF-LIFE OF HBs ANTIBODY AFTER HEPATITIS B VACCINATION: AN AID TO TIMING OF BOOSTER VACCINATION

Antibody to hepatitis B virus surface antigen was measured in 48 paired sera from healthy medical staff who had been vaccinated against hepatitis B. The rate of antibody decline seemed unrelated to the height of the post-vaccination antibody titre and varied widely: even after correction for error of measurement, half-lives ranged from 40 to 280 days (mean 150, SD 52). For maintenance of protection, the recommended date for revaccination should be based on both the post-vaccination antibody level and the half-life, determined individually on completion of vaccination.

Side-effects and Immunogenicity of Haemophilus influenzae Type B Polysaccharide Vaccine in a Multiethnic Pediatric Population

Side-effects and immunogenicity of the Haemophilus influenzae type B polysaccharide vaccine (Hbpv) were reported following introduction in a multi-ethnic border population of 2- to 6-year-old U.S. military dependents. Eighty percent of 659 vaccinees were reported by parents to have no reactions within 48 hours following vaccination; 20% were reported to have local and/or systemic reactions. Each reaction was reported with one-fifth or less the frequency previously reported following DPT vaccination. Serologic data are presented on 114 of the vaccinees. The frequency of pre-vaccination levels reportedly associated with immunity ranged from a lower than expected 54% of 2-year-olds to an expected 86% of 5-year-olds. Post-vaccination levels reportedly associated with immunity ranged from a lower than expected 80% of 2-year-olds to an expected 93% of 5-year-olds. Of the 114 vaccines with serologic data, those with side-effects had serologic changes comparable to those without side-effects. There was no difference in side-effects or immunologic response across ethnic groups. Therefore, side-effects, immunologic responses, and ethnic group appear to be independent variables.

IMMUNIZATION OF PEDIATRIC ONCOLOGY PATIENTS WITH HAEMOPHILUS INFLUFNZAE TYPE B (HIB) POLYSACCHARIDE VACCINE

Although at increased risk for Hib infection, there are limited data concerning safety and immunogenicity of Hib polysaccharide vaccine in children with malignancies. 43 children with malignancies (19 with acute lymphoblastic leukemia, ALL, age 3-20y;15 with Hodgkins Disease, HD, s/p splenectomy, age 16-22y; 9 with other malignancies, age 2-19y) received 25mg vaccine SQ (b CAPSA-I, Praxis Biologies). At time of vaccination, patients were not receiving induction chemotherapy and were not neutropenic. The vaccine was extremely well tolerated with no side effects in anyof 43 children. Prevacclnation anti-PRP antibody (by RIA) was<0.15 meg/ml in 8 of 19 with ALL (geo mean 0.25mcg/ml), 2 of 15 with HD (geo mean 0.70) and 2 of 10 with other malignancy (geo mean 0.58). Inadequate response (Imo postvaccination Ab level of< 1mcg/ml) was found in 10 of 18 with ALL (geo mean 1.1mcg/ml, 4 of 19 had< 0.15mcg/ml), 5 of 11 with HD (geo mean 2.1) and 3 of 8 with other malignancies (geo mean 1.71). There was no significant correlation between postvaccination Ab level and age, sex, serum IgG, IgM IgA, absolute lymphocyte or granulocyte count for any of the groups. There was a positive correlation between log pre-and log postvaccination Ab level for all 3 groups (p<.05). For ALL patients, there was a significant negative correlation between no. months of chemotherapy and log post-immunization Ab (p<.01). Thus, immunization with Hib polysaccharide vaccine cannot be relied upon to protect these patients from Hib disease.

Natural and vaccine-related immunity to Streptococcus pneumoniae.

To investigate the protective effects of pneumococcal vaccine, we assayed serum from healthy adults and from elderly bronchitics for antibody and opsonic activity against nine serotypes of S. pneumoniae. Before vaccination, there was no relation between opsonization and the level of antibody measured by RIA. Some serotypes were well opsonized in the absence of detectable antibody to capsular polysaccharide; others were not, despite modest levels of antibody. These in vitro studies did not support the concept that a certain level of antibody (e.g., greater than or equal to 250 ng of antibody nitrogen/ml) was specifically associated with the capacity to opsonize pneumococci. Nearly all postvaccination sera had increased antibody and opsonic activity against all serotypes, but the lack of correlation in any individual serum persisted. RIA showed that pre- and postvaccination levels of antibody in elderly adults with chronic lung disease were similar to those of younger adults. In elderly bronchitics, opsonizing activity for six of the nine serotypes was lower after vaccination, a result of suggesting a possible explanation for the failure of pneumococcal vaccine to be fully protective in these subjects. Elderly subjects had higher levels of antibody to phosphocholine, but when isolated, this antibody did not opsonize any of the vaccine strains of pneumococci. These results suggest that alternative strategies are needed to maximize the protective effect of pneumococcal vaccine in the population at greatest risk.

ANTIBODY RESPONSE OF HUMAN BEINGS FOLLOWING VACCINATION WITH INFLUENZA VIRUSES

Eleven different preparations of influenza virus were used to vaccinate large groups of human beings. The antibody response to these vaccines was measured by means of the in vitro agglutination inhibition test, and the geometric mean titers of sera taken 2 weeks after vaccination were compared. From these comparisons the following conclusions were drawn: 1. There was a wide individual variation in the antibody response of human beings to the same preparation of influenza virus administrated subcutaneously. The amount of antibody produced by a group with a low prevaccination antibody level was very nearly the same as the amount produced by groups that had higher initial levels. 2. The use of the X strain of distemper virus in the preparation of an influenza vaccine did not enhance the antigenicity of the influenza virus present. 3. Within certain limits the mean antibody response of human beings increased as the amount of virus injected was increased. When large amounts of influenza A virus were given, the antibody response was of the same order of magnitude as that which occurred following actual infection by this virus. 4. When the vaccine was prepared from allantoic fluid, there was no significant difference in the antibody response of human beings given active virus, formalin-inactivated virus, heat-inactivated virus, or virus inactivated by the drying process. 5. Ground infected chick embryos, when diluted with infected allantoic fluid, gave a greater antibody response than allantoic fluid alone (when the virus remained active). The antigenicity of such a preparation was diminished when the virus was inactivated by formalin. 6. Antibody levels 6 and 9 weeks after vaccination showed a marked drop from the 2-week postvaccination levels. In a small group the antibody levels at 5 months were still further reduced. Those individuals who possessed the higher titers tended to lose their antibodies faster than did those at a lower level.