Biomedical subjects

R Clemens

Publications and source records attributed to R Clemens.

At least 19 recordsLinked to original sources

PubMed1999

Reactogenicity and immunogenicity of a new live attenuated combined measles, mumps and rubella vaccine in healthy children.

OBJECTIVE: To compare the reactogenicity and immunogenicity of a novel live attenuated measles-mumps-rubella vaccine, SB MMR (Priorix; SmithKline Beecham Biologicals), with a widely used MMR vaccine, Merck MMR (M-M-R II; Merck & Co. Inc). METHODS: A total of 4702 healthy children, ages 9 to 24 months, were enrolled in 8 single blind, randomized, controlled trials. Reactogenicity (local and general solicited symptoms and all unsolicited symptoms) was assessed for up to 42 days postvaccination. Immunogenicity [seroconversion rates and geometric mean titers (GMT)] was assessed at 42 or 60 days postvaccination in 1912 subjects in 7 studies. In two studies the persistence of the antibodies at Month 12 postvaccination was assessed in 201 subjects. RESULTS: Local symptoms (pain on or immediately after injection; pain, redness and swelling within 4 days of injection) were reported less frequently after SB MMR than Merck MMR (P < 0.0001). General symptoms and all other events were similar between the two groups. Fever >39.5 degrees C was reported after 9.5 and 11.9% of the SB MMR and Merck MMR doses, respectively. At Days 42 to 60 postvaccination seroconversion rates for antimeasles antibodies were higher with SB MMR than with Merck MMR (98.7% vs. 96.9%, P < 0.031) but similar in both groups for anti-mumps and anti-rubella antibodies, GMTs being approximately 10% higher (P < 0.05) with Merck MMR than with SB MMR. At the Month 12 assessment the seropositivity rates and GMTs were similar in both groups. CONCLUSION: When administered as primary vaccination in children in the second year of life, the new SB MMR vaccine has been shown to be superior to a comparator vaccine in terms of local reactogenicity, with equivalent immunogenicity.

Analysis of Variance↗

PubMed1998

Increased protected sex and abstinence among Namibian youth following a HIV risk-reduction intervention: a randomized, longitudinal study.

OBJECTIVE: To evaluate an HIV risk-reduction intervention among Namibian adolescents. METHODS: A randomized trial of a 14-session face-to-face intervention emphasizing abstinence and safer sexual practices conducted among 515 youths (median age 17 years and median grade 11) attending 10 secondary schools located in two districts in Namibia. Youths were randomly assigned to the intervention or control condition at the level of the individual. HIV risk behaviours, intentions and perceptions were assessed at baseline, immediately post-intervention and at 6 and 12 months post-intervention. RESULTS: Among all 515 youths who enrolled in the programme, rates of either abstinence or sex with a condom were not different between control and intervention youths at baseline or in the follow-up period. However, analyses conducted among the subset of youths who were sexually inexperienced at baseline (n = 255) revealed that a higher percentage of intervention youths (17%) than control youths (9%, P<0.05) remained sexually inexperienced one year later. Moreover, in the immediate post-intervention period, among baseline virgins who subsequently initiated sex, intervention youths were more likely than control youths to use a condom (18 versus 10%, P<0.05). Additional HIV-related risk behaviours (failure to discuss previous HIV risk exposure with one's sexual partner and alcohol use), intentions to use condoms, and perceptions of the ability to use condoms were positively affected by the intervention. CONCLUSIONS: There is evidence that the 'My Future is My Choice' (MFMC) intervention is reducing HIV risk behaviours among sexually inexperienced participants aged 15-18. Related risk behaviours and perceptions are also positively impacted by the intervention.

Adolescent↗

PubMed1998

Safety and immunogenicity of hepatitis A vaccine in patients with chronic liver disease.

Acute hepatitis A superimposed on chronic liver disease (CLD) has been associated with severe or fulminant hepatitis. An open, multicenter study was performed to compare the safety and immunogenicity of an inactivated hepatitis A vaccine in patients with CLD with that in healthy subjects. A secondary objective was to compare the safety of the hepatitis A vaccine with that of a commercial hepatitis B vaccine in subjects with chronic hepatitis C. A total of 475 subjects over the age of 18 years were enrolled into 1 of 5 groups according to history, serological data, and previous diagnosis. Patients in groups 1 (healthy adults), 2 (chronic hepatitis B), 3 (chronic hepatitis C), and 5 (other CLD not caused by viral hepatitis) were vaccinated with two doses of inactivated hepatitis A vaccine, 6 months apart. Patients in group 4 (chronic hepatitis C) received 3 doses of a recombinant hepatitis B vaccine, according to a 0-, 1-, and 6-month schedule. Local injection-site symptoms were the most common reactions reported following vaccination in all groups (35.5% of all doses), with the hepatitis B vaccine eliciting fewer injection-site symptoms than the hepatitis A vaccine (19.8% compared with 37.5%). Although a higher percentage of healthy subjects (93%) seroconverted after a single dose of the hepatitis A vaccine than did subjects with chronic hepatitis C (73.7%) or CLD of nonviral etiologies (83.1%), more than 94% of all vaccinees were seropositive for anti-HAV after the complete vaccination course. At each time point, a lower geometric mean concentration of anti-HAV was observed for each group of CLD patients compared with the healthy control subjects. In conclusion, hepatitis A vaccine was well tolerated and induced a satisfactory immune response in patients with chronic hepatitis B, chronic hepatitis C, and miscellaneous CLD.

Adolescent↗

PubMed1998

Immunogenicity and reactogenicity of a Haemophilus influenzae type b tetanus conjugate vaccine when administered separately or mixed with concomitant diphtheria-tetanus-toxoid and acellular pertussis vaccine for primary and for booster immunizations.

UNLABELLED: With an increasing number of new vaccines available for routine childhood immunization, combination vaccines are needed in order to maintain or achieve a high compliance with recommended immunization programmes. In a prospective, randomized, comparative, multi-centre study, 822 healthy infants were enrolled to receive three doses of either a candidate or a commercially available Haemophilus influenzae type b (Hib) vaccine concomitantly with diphtheria-, tetanus- acellular pertussis (DTaP) vaccine. Study subjects were randomly allocated to one of the following groups: (1) separate, or (2) mixed injection of DTaP and candidate Hib vaccine, or (3) separate injection of DTaP and commercial Hib vaccine. One year later the first 189 study subjects received either separate or mixed injections of the same Hib and DTaP vaccines as booster doses. Evaluation of reactogenicity was based on diary cards completed by parents. Immunogenicity was documented by measuring IgG antibody concentrations in serum samples taken before and 4 weeks after primary and booster vaccination. No serious adverse events occurred and most local and systemic reactions were mild to moderate. Booster doses were more reactogenic than primary doses with all groups. Antibody concentrations against pertussis antigens were similar to those seen with DTaP alone. All but one subject had protective antibody concentrations against diphtheria and tetanus. Primary immune response to the Hib vaccine was significantly lower in the group receiving the mixed Hib-DTaP vaccine, however, > or = 95% of vaccinees had anti-Hib antibody concentrations > or = 0.15 microg/ml and there was a marked booster response (> 100-fold) in all groups. CONCLUSIONS: Mixing DTaP and Hib vaccines for primary immunization caused a decrease in anti-Hib antibody response, although after primary immunization as after booster doses, all subjects showed antibody concentrations considered to be protective for invasive Hib disease. Mixing of the vaccines did not result in increased reactogenicity.

Analysis of Variance↗

PubMed1998

The influence of major histocompatibility complex class II genes and T-cell Vbeta repertoire on response to immunization with HBsAg.

Nonresponsiveness to HBsAg vaccination is observed in 5-10% of vaccine recipients and is possibly caused by a defect in the T helper cell compartment. The immune response to HBsAg is influenced by genes of the major histocompatibility complex. We have investigated MHC class I and class II antigens in 53 adult responders and 73 nonresponders. Results obtained in this first study were tested in a second study with 56 responders and 62 nonresponders from an infant vaccination trial. In addition, the peripheral Vbeta-chain T-cell receptor repertoire was investigated using monoclonal antibodies and flow-cytometry in 26 adult responders and 38 nonresponders. As previously reported, nonresponsiveness to HBsAg vaccination was associated with DRB1*3 and DRB1*7. In addition, DRB1*13 was significantly increased among vaccine responders (35.2% vs 5.4%;p < 0.0001) suggesting an immune response promoting effect for this allele whereas the closely related allele DRB1*14 was associated with nonresponse in the infant study. There was no evidence for a hole in the T cell receptor Vbeta repertoire. In conclusion, in agreement with results obtained in mice there appears to be a hierarchy of DRB1* genes in the HBsAg immune response. The possible differential association of DRB1*13 and DRB1*14 may allow the identification of differences between responsiveness and nonresponsiveness to a few amino acid differences in the beta1-domain of the class II heterodimer.

Adult↗

PubMed1997

Immune Response to Hepatitis A Vaccine Combined or Given Simultaneously with Typhoid Fever Vaccine.

Background: Because both hepatitis A and typhoid vaccination are frequently indicated in the same traveler, a prospective, randomized controlled study was performed to evaluate the feasibility of simultaneous administration of hepatitis A and typhoid fever vaccines in adult volunteers. Methods: Two groups of 25 subjects received either separate injections of hepatitis A (Havrixtrade mark, SmithKline Beecham Biologicals) and typhoid fever (Typhim Vitrade mark, Pasteur-Mérieux) vaccines in opposite arms, or a syringe-mixed combination of both vaccines as a single injection. A booster dose of Havrix was given at 6 months. Results: The immune response to hepatitis A tended to be higher in the mixed-injection group, but this difference was significant (p=.048) only following the booster dose. Adverse reactions were generally mild with no differences between the two groups. Conclusion: A combined formulated vaccine against both typhoid fever and hepatitis A is feasible and offers more convenience without added adverse reactions to travelers who have appropriate indications for both vaccines.

Journal Article↗

PubMed1997

[New developments in diagnosis and therapy of primary non-Hodgkin's lymphoma of the central nervous system].

Primary central nervous system lymphomas (PCNSLs) are increasing in frequency both in immunocompetent and immunodeficient individuals. The majority of PCNSLs are high grade B cell lymphomas. In AIDS patients most tumors contain EBV genome. PCNSLs usually present as intracerebral, often deep-seated lesions half of which are multilocular. Less frequent are diffuse periventricular, exclusively leptomeningeal, ocular or spinal spread. On imaging PCNSLs show as contrast-enhancing lesions with relatively little perifocal edema. CSF protein is usually elevated. Malignant cells are present in 20-30% of cases. Demonstration of a monoclonal B cell population by immunocytology or FACS analysis may also be diagnostic. Once PCNSL is suspected extensive systemic evaluation is not useful. Instead, (stereotactic) biopsy of brain lesion(s) should be performed. Prior to biopsy, corticosteroids should be withheld as they may obscure diagnosis. Symptomatic edema or increased intracranial pressure should therefore initially be treated with osmotherapeutics. All immunodeficient patients should receive empiric anti-toxoplasmosis therapy for about 14 days prior to biopsy. AIDS patients with PCNSL survive 3 to 5 months (median) after whole brain irradiation and usually do not benefit from chemotherapy. Immunocompetent patients have a median survival of 12 to 18 months after whole brain irradiation alone, but a median survival of 33 to 43 months after combined radiochemotherapy using cytostatic drugs which penetrate the blood-brain barrier. Based on these encouraging results current concepts aim to intensify chemotherapy and to reduce or delay radiotherapy in the treatment of immunocompetent patients.

Central Nervous System Neoplasms↗

PubMed1997

Evidence for induction of polysaccharide specific B-cell-memory in the 1st year of life: plain Haemophilus influenzae type b-PRP (Hib) boosters children primed with a tetanus-conjugate Hib-DTPa-HBV combined vaccine.

UNLABELLED: The lack of an adequate immune response to the major polysaccharide of the Haemophilus influenzae type b (Hib) capsule (polyribosyl ribitol phosphate) (PRP) in very young infants (< 18 months) can be overcome by conjugating PRP to a T-cell dependent carrier protein. We studied whether administration of a tetanus-PRP conjugate vaccine reconstituted with a diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HBV) vaccine as a three dose primary course at 3, 4 and 5 months of age induced PRP-specific immunological memory, by examining the anti-PRP response to a dose of unconjugated PRP given with the DTPa-HBV booster approximately 1 year later. The unconjugated PRP elicited protective anti-PRP antibody levels (> or = 0.15 microgram/ml) in all but 3 of the 369 vaccinees, including 13 infants who failed to demonstrate a measurable immune response after the primary course. In a sub-cohort of 54 subjects all had anti-PRP levels > or = 0.5 microgram/ml within 7-14 days of the booster showing a rapid anamnestic type response. Both primary and booster responses were predominantly IgGl indicating a T-cell dependent response. The DTPa-HBV components elicited protective anti-diphtheria, anti-tetanus and anti-HBs antibody levels in > or = 98.5% of vaccinees, and immune responses to each of the acellular pertussis vaccine components in 92.3%-97.3% of subjects. CONCLUSION: The tetanus-PRP conjugate vaccine not only elicited a good primary humoral response, but also induced immunological memory so that the infants were able to mount a large and rapid immune response to subsequent exposure to plain PRP, indicating that protection against circulating wild-type Hib had been generated. Successful induction of immunological memory occurred even when there was no measurable humoral anti-PRP response to the primary course. Tetanus-PRP conjugate vaccine can be used in combination with DTPa-HBV vaccine, when administered separately or as a single injection in the same syringe, in primary immunisation schedules at 3, 4 and 5 months of age.

Age Factors↗

PubMed1997

Reactogenicity and immunogenicity of a booster dose of a combined diphtheria, tetanus, and tricomponent acellular pertussis vaccine at fourteen to twenty-eight months of age.

OBJECTIVES: The primary objective was to assess the nature and incidence of adverse events after a fourth dose of a tricomponent acellular pertussis-diphtheriatetanus vaccine given in the second year of life after primary vaccination with the same vaccine at 3, 4, and 5 months of age. A secondary objective was to analyze the immunogeniecity of the booster vaccination. DESIGN: Of the 5361 children enrolled (aged 14 to 28 months), adverse reactions were specifically solicited from the first 1863 enrollees for the first 4 days after vaccination and then were unsolicited for the remainder of the 4 weeks of follow-up (group 1). In the next 3498 subjects, safety and reactogenicify were entirely unsolicited for this 4-week period (group 2). Immunogenicity was analyzed by means of prebooster and postbooster serum antibody titers for all vaccine components in a random subgroup of 197 children from group 1. RESULTS: Soliciting symptoms elicited reports of at least one symptom in 1314 of 1809 children in group 1 (72.6%), including 993 (54.9%) with local and 885 (48.9%) with general symptoms during the first 4 days after vaccination. When symptoms were gathered in an unsolicited fashion, only 580 of 3498 children in group 2 (16.6%) had a reported symptom during this time, consisting of 344 (9.8%) local and 319 (9.1%) general symptoms, respectively. An unsolicited symptom, areactive edematous swelling of the whole thigh, occurred in 62 children (1.1%), with 45 and 17 reports in groups 1 and 2, respectively. The vast majority of all reported symptoms were mild to moderate, and all children recovered without sequelae. Fourteen serious adverse events were reported, but none was considered to be related to the vaccination. Immunogenicity analysis showed a vaccine response to pertussis toxin in 99.5% of subjects, to filamentous hemagglutinin in 98.5%, and to pertactin (69 kd outer membrane protein) in 99%. All subjects had postvaccination antibody titers of 0.1 IU/ml or greater against diphtheria and tetanus toxoids.

Antibody Formation↗

PubMed1997

Booster immunization of low- and non-responders after a standard three dose hepatitis B vaccine schedule--results of a post-marketing surveillance.

Seventy-nine low-responders and 83 non-responders after a previous three-dose hepatitis B (HB) vaccine course at 0.1, and 6 months were enrolled to receive additional 20 micrograms recombinant HB vaccine doses every 2 months until all had anti-HBs levels > or = 100 mIU ml-1. After the first booster, 65.4% had anti-HBs levels > or = 100 mIU ml-1, 17.9% were low-responders (10-99 mIU ml-1), and 16.7% remained non-responders (< 10 mIU ml-1). All complying non-responders developed anti-HBs levels > or = 100 mIU ml-1 after the third booster at the latest, whereas all low-responders reached this level after the second booster. Although body mass index affected the response to the first hepatitis B booster, when full compliance to regular revaccination was ensured, all non- and low-responders eventually reached sufficient anti-HBs levels.

Adolescent↗

PubMed1997

Feasibility study of a combined diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HBV) vaccine, and comparison of clinical reactions and immune responses with diphtheria-tetanus-acellular pertussis (DTPa) and hepatitis B vaccines applied as mixed or injected into separate limbs.

The feasibility of a combined diphtheria-tetanus-acellular pertussis-hepatitis B (DTPa-HBV) vaccine was assessed and a comparison made of immunogenicity and reactogenicity to DTPa and HBV vaccines mixed in one syringe and to concomitant but separate injections as a primary vaccination course in three groups of infants at 3, 4.5 and 6 months of age. All subjects attained protective levels of anti-HBs antibodies 1 month after the primary course with higher geometric mean titres (GMTs) in the combined or mixed vaccinations. GMTs for pertussis toxin (PT), filamentous haemagglutinin (FHA) and pertactin (PRN) were as good or better in the groups administered the combined formulation and the extemporaneously mixed vaccines than the separate administration. No serious adverse event related to the vaccination was reported in this study. Neither the combined formulation of DTPa and HBV vaccines nor the extemporaneous mixture increased the incidence or severity of adverse reactions compared with the separate administration of DTPa. This study shows the feasibility of a combined DTPa-HBV vaccine and the data support, in the interim, the mixing of DTPa and HBV vaccines which are tested in clinical trials for infant immunization.

Antibodies, Bacterial↗

PubMed1997

Potential of the monoglyceride and triglyceride of DL-3-hydroxybutyrate for parenteral nutrition: synthesis and preliminary biological testing in the rat.

Esters of short-chain organic acids have shown some promise as potential nutrients for parenteral feeding. Most glycerols are water insoluble but those of the ketone bodies have some water solubility. Of interest is that the triacylglycerol of 3-hydroxybutyrate has water solubility while the triacylglycerol of acetoacetate does not. The mono- and triacylglycerol of DL-3-hydroxybutrate were synthesized and tested for toxicity and nutritional value as parenteral nutrients. Both compounds have an estimated energy density of 19.7 kJ/g (4.7 kcal/g) and are water soluble. The compounds were infused into rats for 7 d at a rate to provide 113 kJ/d and were accompanied by a low-energy oral diet. Control, pair-fed rats were infused with isocaloric glucose or 0.9% saline. Nitrogen intake, output, and balance, body weight changes, and liver size were compared. The two glycerols of 3-hydroxybutyrate supported similar nitrogen retention, body weight changes, and liver size as found in the pair-fed control animals infused with glucose. Rats infused with saline retained less nitrogen, had decreased body weight, and had smaller livers. The data demonstrated that the glycerols of DL-3-hydroxybutyrate are not toxic, provide metabolic energy when infused intravenously, and could be used as nutrients for parenteral feeding.

3-Hydroxybutyric Acid↗

PubMed1997

Cell-mediated immunity after pertussis vaccination and after natural infection.

The aim of this study was the investigation of the specific cell-mediated (CMI) responses induced by DTaP and to compare these data to immunity after natural infection. The ability of peripheral blood T-lymphocytes to respond to the pertussis related antigens pertussis-toxin (PT), filamentous haemagglutinin (FHA), and Pertactin (PRN) was investigated in 40 children before vaccination and at different times after vaccination with DTaP (Infanrix) by measurement of antigen-specific proliferation, lymphocyte phenotype, cytokine production and expression of activation markers (CD25, HLADR). Similar investigations were performed in children 4-6 weeks after recovery from natural pertussis. DTaP created a specific T-cell-response to PT, FHA and PRN that increased continually, depending on the progress of the vaccination schedule. In contrast to waning antibody titres, CMI was stable even between the post-basic vaccination and the pre-booster period. The magnitude of CMI after DTaP equalled those after natural infection. Measurement of cytokine-pattern showed induction of IFN-tau-producing T-helper-1-cells with lower stimulation of IL 10-producing T-helper-2-cells for DTaP and natural infection. Our data indicate that DTaP-vaccination induces a potent immune response to PT, FHA, and PRN at least equivalent to CMI after natural infection. The finding of a preferential T-helper-1-induction after DTaP and natural infection suggests a role of IFN gamma-activated macrophages in the protective response against B. pertussis-induced disease.

Adhesins, Bacterial↗

PubMed1997

Safety and efficacy of acellular pertussis vaccines: the Mainz study and other recent studies.

Following concerns about the safety and reactogenicity profile of diphtheria, tetanus and whole cell pertussis vaccines (DTwP), new and less reactogenic alternatives were developed over the last two decades. The new diphtheria, tetanus and acellular pertussis vaccines (DTaP) no longer consist of the whole bacterial cell but of either extracts or of a few highly purified components. While it soon became clear that DTaP vaccines are significantly less reactogenic than DTwP vaccines, their efficacy was disputed and remained unproven. First studies and epidemiological data from Japan suggested vaccine efficacy rates (VE) of about 80%; however, the first blinded clinical trial from Sweden documented a much lower VE. Worldwide, seven large DTaP efficacy trials have recently been completed. Our own efforts included a large safety trial with 22505 vaccinees and, nested in this setting, a prospective household contact study. Typical WHO-defined pertussis developed in 7 of 112 DTaP vaccinated children following household exposure as compared to 96 cases in 173 children not vaccinated against pertussis. Thus, vaccine efficacy was calculated to be 88.7% (95% CI 76.6 to 94.6). The median duration of spasmodic cough in the few children vaccinated with DTaP who did start coughing was 17 days as compared to 35 days in unvaccinated children. No waning of protection was observed. None of the confounding variables analyzed influenced study results in favour of DTaP. Following administration of more than 67000 DTaP doses, 153 serious adverse events were reported. Eight events were considered possibly related and five were considered related to the study vaccine. According to additional study results from the other trials it can be concluded that DTaP vaccines, like DTwP vaccines, are safe and effective. The choice between DTwP and DTaP should be based on acceptance of the reactogenicity profile, coverage rates achieved, costs and other factors in each individual country.

Clinical Trials as Topic↗

PubMed1996

Immunogenicity of a recombinant hepatitis B vaccine in adults.

OBJECTIVES: To evaluate the immunogenicity and reactogenicity of a recombinant hepatitis B vaccine in health care staff under routine use and unselected conditions and to investigate factors that influence the response to vaccination. METHODS: This prospective postmarketing surveillance study was performed in unselected health care staff and their relatives (age range, 12-60 years) at 58 hospitals. Overall, 880 subjects were administered a 20-microgram dose of a vaccine at 0, 1, and 6 months according to the prescribing information and under routine hospital practice, and they were tested for antibody to hepatitis B surface antigen after the third dose at the hospitals routine laboratory. The principal outcome measures were antibody to hepatitis B surface antigen titers that were expressed as the seroprotection rate (SPR) (SPR [given as a percentage], > or = 10 mlU/ mL), spontaneously reported adverse events, and geometric mean titers (in milli-international units per milliliter). RESULTS: The compliance to the 3-dose schedule under routine hospital practice was 98.1%. The immune response was good in all age groups, and the overall SPR was 97.8% at 1 month after the third dose in field conditions with unselected health care workers. The SPR in vaccinees (age range, 40-59 years) was close to 95%. Age (P < .001), smoking (> or = 10 cigarettes per day) (P < .001), Broca index (> 110%) (P < .001), antibody to hepatitis B surface antigen testing (> 8 weeks after the last dose) (P = .03), chronic underlying disease (P = .04), and male gender (P = .04) were factors associated with lower geometric mean titers in routine vaccine use. No serious adverse events were reported. CONCLUSION: The large immune response that was elicited by this hepatitis B vaccine in adults under daily routine field conditions reflected reality, with a high SPR also found in elderly and other persons with risk factors associated with a lower immune response.

Adolescent↗

PubMed1996

Efficacy of acellular pertussis vaccine in early childhood after household exposure.

OBJECTIVE: To evaluate the efficacy of a three-dose primary vaccination with a diphtheria-tetanus tricomponent acellular pertussis vaccine against "typical" pertussis, defined as a spasmodic cough of 21 days or longer with confirmation of Bordetella pertussis infection by culture or serology. DESIGN: Passive monitoring for suspected first household (index) cases of typical pertussis in six areas in Germany comprising 22,505 children vaccinated with study vaccine at 3, 4, and 5 months of age. Blinded, prospective follow-up of household contacts of index cases for incidence and progression of pertussis. SETTING: Six areas in Germany with a high incidence of pertussis. SUBJECTS: Four hundred fifty-three households with index cases comprising 360 evaluable contacts eligible for analysis of vaccine efficacy. MAIN OUTCOME MEASURE: Vaccine efficacy from attack rates of pertussis in household contacts classified by vaccination status. RESULTS: Of the 173 nonvaccinated household contacts, 96 developed typical pertussis, compared with seven of 112 contacts vaccinated with acellular pertussis vaccine. Vaccine efficacy was consequently calculated to be 88.7% (95% confidence interval, 76.6% to 94.6%). Protection did not wane until at least the time recommended for booster vaccination. None of the analyzed potential confounding factors--age, socioeconomic status, erythromycin treatment, household composition, center effect, and selection bias--influenced study results in favor of the vaccine. CONCLUSIONS: Under conditions of intense household exposure, primary vaccination with acellular vaccine protected against pertussis until at least the time recommended for booster vaccination. The vaccine can be expected to be equally or more effective in settings with lower infectious pressure.

Bordetella pertussis↗

PubMed1996

Immunogenicity of an inactivated hepatitis A vaccine administered according to two different schedules and the interference of other "travellers" vaccines with the immune response.

A total of 2036 persons consulting vaccination centers in Germany were vaccinated with an inactivated hepatitis A vaccine (containing 720 ELISA units of antigen) either according to the standard schedule (two vaccinations given 4 weeks apart) or to an abbreviated schedule (two vaccinations given 2 weeks apart) in a controlled clinical study. The abbreviated schedule induced a similar rate of seroconversion and geometric mean antibody titre as compared to the standard schedule. The incidence of reactions reported after vaccination was similar in both groups. When other "travellers" vaccines were given simultaneously neither the immunogenicity nor the reactogenicity of the hepatitis A vaccine were influenced. These findings have considerable practical importance in the prevention of hepatitis A in travellers.

Adolescent↗

PubMed1996

Clinical experience of a tricomponent acellular pertussis vaccine combined with diphtheria and tetanus toxoids for primary vaccination in 22,505 infants.

OBJECTIVES: To assess the safety and tolerability of 12 lots of SmithKline Beecham Biologicals' diphtheria-tetanus-tricomponent acellular pertussis vaccine (DTaP) in a large cohort of 22,000 vaccinees, with detailed analyses of reactivity, immunogenicity, and immune response to pertussis toxin in subsets. METHODS: In a prospective, double-blind, multicenter trial in Germany, 22,505 healthy infants received three vaccinations of DTaP at age 3, 4, and 5 months. Serious adverse events were followed for 1 month after each vaccination, and neurologic events for 1 year or longer. Serum IgG antibodies were assayed before vaccination and 1 month after vaccination. RESULTS: After 67,000 doses, 153 serious adverse events (0.23%) were reported, 8 considered possibly related, and 5 related to vaccination, including 1 hypotonic-hyporesponsive episode. Incidence rates of sudden infant death syndrome (7; 0.01%) or acute neurologic events (20; 0.030%) were no higher than expected and not considered to be related to vaccination. Redness and swelling of 20 mm or greater occurred after 44 (0.6%) and 40 (0.6%) of the 7270 doses, respectively, and high fever (> 39.5 degrees C) in 6 (0.08%) subjects within 48 hours of vaccination. In the immunogenicity analysis of 580 infants, 98% responded to pertussis toxin, 96% to filamentous hemagglutinin, and 98% to pertactin. In an additional 5712 infants, the response rate to pertussis toxin was 99%. CONCLUSIONS: In a large cohort of 22,505 infants vaccinated, SmithKline Beecham Biologicals' tricomponent DTaP vaccine was shown to be safe, well-tolerated, and immunogenic for all component antigens.

Diphtheria-Tetanus-Pertussis Vaccine↗