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H J Schmitt

Publications and source records attributed to H J Schmitt.

At least 19 recordsLinked to original sources

Assessment of nine candidate DTP-vaccines with reduced amount of antigen and/or without adjuvant as a fourth (booster-) dose in the second year of life.

BACKGROUND: The incidence of local reactions to diphtheria-, tetanus and acellular pertussis (DTaP-) vaccines in infants and toddlers increases with each subsequent dose, and entire thigh swellings (ETS) have been reported. Lowering the amount of antigen or of adjuvant may decrease the reactogenicity of DTaP while maintaining a protective immune response. OBJECTIVES: Following priming with three doses of a DTaP vaccine during infancy, the safety, reactogenicity and immunogenicity of nine different candidate DTaP-vaccines with reduced amounts of antigen and/or adjuvant given as fourth (booster) dose were evaluated. METHODS: Study participants were healthy infants aged 15-27 months at the time of booster vaccination. Each participant had received three doses of a DTaP vaccine (Infanrixtrade mark, GlaxoSmithKline, Rixensart, Belgium; "reference DTaP") at age 3, 4, and 5 months as part of a previous clinical trial. More than 20,000 children were eligible for participation in the current study protocol at the time. In a first phase at a University hospital-based vaccination study center, nine sequential cohorts of 63-119 study subjects received one of nine different candidate vaccines. Patients and study personal were blinded with regard to which vaccine was currently in use. Reactogenicity was solicited from parents using diary cards. Blood was drawn prior to and 4 weeks after vaccination and immediately centrifuged. The serum was stored at -20 degrees C until serology was performed by ELISA tests. As soon as the first candidate vaccine with adequate reactogenicity and immunogenicity profile was identified in the first study phase, a second study phase was initiated in parallel, to evaluate the safety and reactogenicity of the respective candidate vaccine in private practices in large cohorts (1613-2095 study subjects per group). RESULTS: In the first study phase, DTaP with no aluminum induced the highest frequency of ETS and fever. All other candidate vaccines caused lower rates of local and general reactions than the reference DTaP. As a general rule, vaccines with less antigen induced fewer reactions, although there was no strict dose-response effect and the difference, e.g. between a one-tenth and a one-fifth DTaP dose (DTaP 1/5; DTaP 1/10) was not clinically relevant. Separate injections of Td and aP caused fewer general reactions than the respective TdaP combination and local reactions were higher at the aP than at the Td injection site. Again, as a general rule, reduced amounts of antigen induced lower antibody concentrations, although all vaccines induced "protective" anti-tetanus and anti-diphtheria antibody responses. A total of 92-100% of children showed seroresponses to pertussis antigens even when vaccinated with reduced amounts of the respective pertussis antigen. Elimination of aluminum from DTaP vaccine induced higher anti-tetanus-antibody concentrations and so did a reduction of the amount of diphtheria antigen. Additional examples for antigen interaction were increased antibody concentrations, observed with injection of Td and aP into different limbs. In the second study phase, all three vaccines evaluated (one with a reduced amount of diphtheria antigen, TdaP; one with reduced amounts of all antigens, tdap; and one with a fifth dose of the reference vaccine (DTaP 1/5)) were safe and had an acceptable reactogenicity profile in a total of 4871 study subjects. CONCLUSIONS: Local reactions due to DTaP booster doses in the second year of life can be reduced by reducing the amount of antigen in the respective vaccine while an adequate immunogenicity is maintained. Aluminum-free vaccines induced ETS and fever most commonly. Any changes in vaccine composition should lead to a full evaluation of the new product.

Adjuvants, Immunologic↗

Onset and duration of mivacurium-induced neuromuscular block in patients with Duchenne muscular dystrophy.

BACKGROUND: To determine the response to mivacurium, we prospectively studied onset time and complete spontaneous recovery from mivacurium-induced neuromuscular block in patients with Duchenne muscular dystrophy (DMD). METHODS: Twelve boys with DMD, age 5-14 yr, seven of them wheelchair-bound, ASA II-III, and 12 age- and sex-matched controls (ASA I) were enrolled in the study. Anaesthesia was induced with fentanyl 2-3 microg kg(-1) and propofol 3-4 mg kg(-1) titrated to effect, and maintained by continuous i.v. infusion of propofol 8-12 mg kg(-1) and remifentanil as required. The lungs were ventilated with oxygen in air. Neuromuscular transmission was assessed by acceleromyography using train-of-four (TOF) stimulation every 15 s. After baseline readings, a single dose of mivacurium 0.2 mg kg(-1) was given. The following variables were recorded: (i) lag time; (ii) onset time; (iii) peak effect; (iv) recovery of first twitch from the TOF response to 10, 25 and 90% (T(10), T(25), T(90)) relative to baseline; (v) recovery index (time between 25 and 75% recovery of first twitch); and (vi) recovery time (time between 25% recovery of first twitch and recovery of TOF ratio to 90%). For comparison between the groups the Mann-Whitney U-test was applied. RESULTS: There were no differences between the groups in lag time, onset time and peak effect. However, all recorded recovery indices were significantly (P<0.05) prolonged in the DMD group. The median (range) for time points T(10), T(25) and T(90) in the DMD and control group was 12.0 (8-16) vs 8.4 (5-15) min, 14.1 (9-20) vs 10.5 (7-17) min and 26.9 (15-40) vs 15.9 (12-23) min, respectively. The recovery index and recovery time were similarly prolonged in the DMD group. CONCLUSIONS: These results support the assumption that mivacurium-induced neuromuscular block is prolonged in patients with DMD.

Adolescent↗

Rocuronium for muscle relaxation in two children with Friedreich's ataxia.

Friedreich's ataxia is a rare hereditary neurodegenerative disease caused by a defect in the gene that encodes a mitochondrial protein called frataxin. We report the use of rocuronium 0.6 mg kg(-1) in two adolescent girls with Friedreich's ataxia undergoing propofol-sufentanil-oxygen-air anaesthesia for spinal surgery. Neuromuscular transmission was monitored using acceleromyography, and onset and recovery times were recorded. The clinical duration of rocuronium was comparable to that of children without neuromuscular disease (25% recovery T(1)=44 and 24 min for patients 1 and 2 respectively).

Adolescent↗

The safety, reactogenicity and immunogenicity of a 7-valent pneumococcal conjugate vaccine (7VPnC) concurrently administered with a combination DTaP-IPV-Hib vaccine.

To evaluate immune responses, safety and reactogenicity of the concomitant use of DTaP-IPV-Hib and the newly available 7-valent pneumococcal conjugate (7VPnC) vaccines when given as the primary immunization series in early infancy. A total of 231 healthy infants were enrolled at 11 German study centers and randomized to receive either 7VPnC plus DTaP-IPV-Hib vaccines concomitantly into opposite limbs at age 2, 3, 4 and 11-15 months (7VPnC group) or DTaP-IPV-Hib vaccine at the same ages plus a 7VPnC "catch-up vaccination" at ages 6, 7, 8 and 11-15 months (Control group). Blood samples were drawn before and 4 weeks after the first three vaccine doses and 4 weeks after the fourth dose. Local and general side effects (i.e. safety) were solicited by diary cards. Immune responses were determined by ELISA except for antibodies to polioviruses (neutralization assay). Post-dose 3, a significant antibody response against all seven pneumococcal vaccine-serotypes was observed in the 7VPnC group only. Post-dose 4 geometric mean concentrations (GMCs) were similar in both groups. GMCs for other vaccine antigens were comparable between groups except for diphtheria (higher in the 7VPnC group) and pertactin (lower in the 7VPnC group), although after three vaccine doses there was a 28-fold rise in GMCs from baseline. Both vaccines were generally well-tolerated although there were minor differences in the frequency of local reactions and somewhat more fever or drowsiness in the 7VPnC group. The use of DTaP-IPV-Hib and the 7VPnC vaccine was safe, well-tolerated and immunogenic when given concomitantly at age 2, 3 and 4 months or when given separately with 7VPnC as a catch-up vaccination at age 6, 7, 8 months and as a concomitant booster immunization at age 11-15 months.

Antibodies, Bacterial↗

An outbreak of rubella aboard a ship of the German Navy.

BACKGROUND: During May and June 1996, an outbreak of rubella occurred offshore aboard a ship of the German Navy. The outbreak spread among 330 crew members over a period of 9 weeks, ending 2 days after the ship's return. This is the first detailed epidemiological investigation of a rubella outbreak on a ship, describing temporal progression, clinical manifestations, immunization status and seroprevalence of the population exposed. PATIENTS AND METHODS: Outbreak investigation using a questionnaire, health records and rubella serology (hemagglutination inhibition (HI) test and EIA). RESULTS: Of the 330 crew members 298 (90%) participated in the investigation. The outbreak was continuous without a peak and ended abruptly after the ship's return. It resulted in 20 cases, 11 of which were clinically symptomatic. A total of 35 (12%) crew members were susceptible to rubella prior to the outbreak, resulting in an attack rate of 57%. The highest risk for infection was linked to accommodation aboard the ratings deck (chi(2)-test, p = 0.004) with most favorable conditions of transmission. Only 9% of the participating crew were able to provide complete proof of their immunization status. The positive predictive value of a past history of rubella for the presence of antibodies against rubella was 59%. CONCLUSION: The transmission of rubella that we describe aboard a ship was facilitated by the unusually close proximity of the crew and their insufficient immunity. Documentation of immunization was inadequate in this population.

Antibodies, Viral↗

Seasonality of respiratory syncytial virus-positive hospitalizations in children in Kiel, Germany, over a 7-year period.

BACKGROUND: Elaborate, long-term data on the rhythm, seasonality and severity of the yearly respiratory syncytial virus (RSV) epidemics in Germany are lacking. PATIENTS AND METHODS: A longitudinal investigation was undertaken of children from birth to 16 years of age admitted with an RSV infection in the two pediatric hospitals in Kiel between July 1994 and June 2001. To compare the severity of the individual seasons, the incidences and the proportion of RSV-positive hospitalized children aged 0 to 2 years from the denominator area of Kiel were compared. RESULTS: During the 7-year period, the nasopharyngeal aspirates of 2,367 children were investigated; RSV was detected in 384 (16.2%). The seasons from 1994/95 to 1996/97 started late (December to January) and ended between March and May. Since 1997/98 it seems that a late season is followed by an early season (start in September to October) in a 2-year pattern. CONCLUSION: No fixed rhythm of the RSV season can be identified as yet. Ascertainment bias is unlikely to explain the differences in rhythm. The incidence of RSV-positive hospitalizations seems to be increasing.

Adolescent↗

Detection of delayed vaccinations: a new approach to visualize vaccine uptake.

For the prevention of pertussis and invasive Haemophilus influenzae type b (Hib) infections, each with a peak for mortality and serious complications in the first year of life, early vaccination is important and needs adequate monitoring. In a 1999 national coverage survey the timing of uptake of these vaccines in German children was therefore assessed conventionally at defined age thresholds and with a new adaptation of the Kaplan-Meier (KM) method estimating immunization uptake over time by 1 minus the survival function s(t). Only 6% and 9% of children were vaccinated against pertussis and Hib in accordance with the national recommended primary vaccination schedule. Coverage levels for the primary vaccination course of 50% and 90% were attained for pertussis after 6.6 and 16.3 months respectively and for Hib after 7.0 and 24.3 months. These estimates were only possible with the KM method which proved useful to monitor vaccination programmes and will allow the comparison of vaccination uptake in different populations.

Female↗

The incidence of influenza-associated hospitalizations in children in Germany.

Since new vaccines and anti-viral drugs for influenza have become available, collation of actual and country-specific epidemiological data is essential. Since respiratory syncytial virus (RSV) is a well known paediatric airway pathogen and some epidemiological data exist already, a comparison between influenza and RSV seems warranted. From July 1996 to June 2001 the naso-pharyngeal aspirates (NPA) of children from birth to 16 years of age, admitted to one of the two paediatric hospitals in Kiel, Germany, were investigated by a nine-valent multiplex reverse transcriptase PCR assay. NPA were investigated in 60.8 % of 3,469 children admitted with an acute respiratory tract infection. Community-acquired or nosocomial infections (in parentheses) due to influenza A were diagnosed in 122 (10) children, due to influenza B in 14 (2) and due to RSV in 325 (24) cases. Patients with influenza A (median 752 days) and influenza B (median 966 days) were older than patients with RSV (median 168 days). The spectrum of disease presentation was broader in influenza than in RSV. In each winter, admissions with influenza were less common than those with RSV. Influenza B only occurred in 2 of the 5 years. The cumulative, population-based incidences per 100,000 children 0-16 (0-5, >5-16) years of age were 53 (123, 22) for influenza A, 16 (30, 9) for influenza B and 165 (453, 4) for RSV. Cardiac conditions and asthma were the major risk factors for admission to hospital with influenza A (RR 9.8, 4.1) and RSV (8.5, 2.1) infections. Underlying conditions were most common in influenza B. Low gestational age doubled the risk for admission to hospital with influenza A infection, but did not show a dose-effect relationship as in RSV. The burden of influenza-positive hospitalizations was about one third that of RSV. The incidence was similar to reports from the United States. Targeting children with underlying conditions, especially cardiac conditions and asthma in the German immunization programme is appropriate, as long as no policy for vaccination of the general paediatric population exists.

Adolescent↗

Ratio of patient's height to thyromental distance improves prediction of difficult laryngoscopy.

Several tests have been proposed to predict difficult laryngoscopy or intubation. The thyromental distance (TMD) is often used for these purposes but this measurement, used alone, is unreliable. This study tested the hypothesis that the ratio of the patient's height to TMD (ratio of height to TMD = RHTMD) would improve the accuracy of predicting difficult laryngoscopy compared with TMD alone. Two hundred and seventy patients were evaluated preoperatively using the TMD and RHTMD. The two tests were compared analyzing the area under the receiver operating characteristic curves (AUC). Difficult laryngoscopy occurred in 16 patients (5.9%). The AUC of RHTMD was significantly greater (P < 0.007) when compared to TMD, indicating a more accurate prediction by the RHTMD. A ratio of 25 for the RHTMD was found to be the optimal cut-off value to predict difficult laryngoscopy. When the sensitivity of both tests was 0.81, the RHTMD had a significantly greater specificity (0.91) than the TMD (0.73). Based on our results, we recommend that the RHTMD should be used instead of the TMD.

Adolescent↗

Factors influencing vaccine uptake in Germany.

While vaccines have virtually eliminated many infectious diseases in Germany, vaccination coverage in children, adolescents and adults is still unsatisfying. This situation is mainly due to inadequate remuneration of vaccination services, structural deficits in the health care system and a lack of motivation. Political support and leadership would most likely be able to change this situation.

Germany↗

Incidence of respiratory syncytial virus-positive hospitalizations in Germany.

Epidemiological data, especially population-based data, on respiratory syncytial virus (RSV)-related hospitalizations in Germany have been lacking to date. Since Palivizumab (Synagis, Abbott, USA) is already available and new vaccines for active immunization are under development, these data are urgently needed. From July 1996 to June 1999, nasopharyngeal aspirates of children hospitalized in Kiel with an acute respiratory tract infection were tested by multiplex reverse transcriptase polymerase chain reaction. Of 1,241 patients, 150 (12.1%) were RSV positive. RSV was the predominant pathogen detected through the end of the second year. In 37 (25%) children an underlying condition was present. For the city of Kiel and close surroundings, the cumulative incidence of RSV-positive hospitalizations in infants was 1,214/10(5) (725/10(5) in children less than 2 years). For those children less than 2 years old born with a gestational age of less than 32 weeks or 32-37 weeks, the cumulative incidence was 2,025/10(5) and 1,202/10(5), respectively (dose-effect response). For the group less than 32 weeks of age, bronchopulmonary dysplasia (BPD) as an underlying condition carried a relative risk of 17.8. The RSV season began between the end of September and January and ended between March and July. The population-based incidence of RSV-positive hospitalizations in Kiel is close to that reported from the UK and Scandinavia. Throughout Germany, approximately 10.000 RSV-related hospitalizations in infants can be expected annually. Prematurity is an effect modifier and BPD a strong risk factor for RSV-positive hospitalization in population-based studies. There is considerable variation in the start and end of the yearly epidemic.

Acute Disease↗