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J D Cherry

Publications and source records attributed to J D Cherry.

At least 37 records · Page 2Linked to original sources
PubMed1998

Comparative Efficacy of the Lederle/Takeda acellular pertussis component DTP (DTaP) vaccine and Lederle whole-cell component DTP vaccine in German children after household exposure. Pertussis Vaccine Study Group.

BACKGROUND: A household contact substudy was performed as part of a prospective, cohort pertussis vaccine efficacy trial in Germany. DESIGN: Infants received four doses of either the Lederle/Takeda acellular pertussis component diphtheria-tetanus toxoids (DTP) vaccine (DTaP) or Lederle whole-cell component DTP vaccine at 3, 4.5, 6, and 15 to 18 months of age (Wyeth-Lederle Vaccines and Pediatrics, Pearl River, NY). An open control group received three doses of diphtheria and tetanus toxoids vaccine (DT) at 3, 4.5, and 15 to 18 months of age. Vaccine efficacy rates were calculated using a number of principal and ancillary case definitions for primary, secondary, and noncases by analyzing secondary attack rates in study infants after exposure to pertussis in the household using 7- to 28- and 7- to 42-day postexposure observation periods and the inclusion and the exclusion of noncases who received macrolide antibiotics or trimethoprim-sulfamethoxazole during the exposure period. RESULTS: During a 3.5-year study period, 10271 infants (DTP or DTaP, n = 8532; DT, n = 1739) were enrolled and actively followed along with all household members for cough illnesses. Depending on the case definition, 160 to 519 household exposures to pertussis were identified. In general, secondary attack rates in DT recipients were low and this was primarily because of the frequent use of antimicrobial prophylaxis. Using the principal case definitions and the exclusion of noncases who received macrolide antibiotics or trimethoprim-sulfamethoxazole during the exposure period and the 7- to 42-day observation period, the efficacy of DTP against cough illness of greater than or equal to 7 days duration caused by Bordetella pertussis was 84% (95% confidence interval [CI] = 65-93) and that of DTaP was 58% (95% CI = 30-75). Using similar criteria, the efficacy against typical pertussis (greater than or equal to 21 days of cough with either paroxysms, whoop, or posttussive vomiting) was 94% (95% CI = 77-99) and 86% (95% CI = 62-95) for DTP and DTaP, respectively. The efficacy against any cough illness (with or without) laboratory confirmation was 54% (95% CI = 32-69) and 38% (95% CI = 13-56) for DTP and DTaP, respectively. CONCLUSION: This household contact substudy within our cohort study, with active investigator-generated surveillance, was a severe test of vaccine efficacy. Both vaccines (DTP and DTaP) are better at preventing typical pertussis than mild illness. When case definitions similar to those in other recent trials are used, the Lederle/Takeda vaccine has an efficacy similar to other multicomponent DTaP vaccines.

Diphtheria-Tetanus-Pertussis Vaccine↗
PubMed1998

The effect of investigator compliance (observer bias) on calculated efficacy in a pertussis vaccine trial.

BACKGROUND: In the course of a large pertussis vaccine efficacy trial we realized that investigator compliance could have a major impact on calculated vaccine efficacy. DESIGN: In our pertussis vaccine efficacy trial, the study investigators were to monitor illness in study families by telephone every 2 weeks. If a cough illness of >/=7 days duration was noted, the study child was to be evaluated. If the cough illness persisted for >/=14 days, the child was to be referred to a central investigator. For this report we analyzed study physician evaluation rates and rates of referral to the central investigators. Physician practices were separated into three compliance categories: high, intermediate, and low. We analyzed vaccine efficacy of an acellular pertussis component DTP vaccine (DTaP) and a whole cell pertussis component DTP vaccine (DTP) by compliance category. Bordetella pertussis infection was documented by culture of the organism in the study child or in a household contact or by a significant antibody response to pertussis toxin determined by enzyme-linked immunosorbent assay. RESULTS: Using a clinical case definition that included both mild and typical pertussis (cough illness >/=7 days duration) efficacy of DTaP vaccine was 40% (95% confidence interval [CI] = -3-65) in the high compliance category and 78% (95% CI = 65-86) and 75% (95% CI = 53-87) in the intermediate and low compliance groups, respectively. Similar, but less marked, differences in efficacy were noted with DTP vaccine recipients. Using a clinical case definition that required >/=21 days of cough with paroxysms, whoop, or vomiting (typical pertussis) the efficacy of DTaP vaccine was 69% (95% CI = 41-83) in the high compliance category and 86% (95% CI = 76-92) and 84% (95% CI = 64-93) in the intermediate and low compliance groups, respectively. In contrast, the efficacy of DTP vaccine did not vary by compliance category using this case definition. The attack rate in children vaccinated with diphtheria and tetanus toxoids vaccine (DT) was twofold less in low compliance physician practices when compared with the rates in high and intermediate groups. The DT/DTaP and DT/DTP fold-change differences were less in the high compliance group compared with the intermediate and low compliance groups. CONCLUSIONS: Our data suggest that observer compliance (observer bias), can significantly inflate calculated vaccine efficacy. It is likely that all recently completed efficacy trials have been effected by this type of observer bias and all vaccines have considerably less efficacy against mild disease than published data suggest.

Clinical Trials as Topic↗
PubMed1997

Comparative efficacy of acellular pertussis vaccines: an analysis of recent trials.

Diphtheria-tetanus-acellular pertussis vaccines have been licensed in the United States since 1991. Compared with the whole cell pertussis component diphtheria-tetanus-pertussis vaccine, the diphtheria-tetanus-acellular pertussis vaccines were found in reactogenicity and immunogenicity studies to be immunogenic with respect to their specific antigen content and to be associated with less severe and less frequent adverse reactions. A case definition of pertussis was developed by the World Health Organization for use in vaccine efficacy trials, but this definition eliminates some laboratory-confirmed cases from efficacy calculations. Because these cases are more common in vaccinees than in controls, vaccine efficacy appears better than it truly is whereas less effective vaccines seem comparable with their more effective counterparts. In addition observer bias may contribute to the appearance of enhanced efficacy of the less effective vaccines, which tend to prevent typical but not mild disease. When analyzing efficacy based on prevention of laboratory-confirmed pertussis with cough > or = 7 days, single component pertussis toxin (PT) toxoid vaccines were found to be less effective than two-component PT toxoid/filamentous hemagglutinin vaccines, and three- or four-component vaccines containing pertactin in addition to PT toxoid and filamentous hemagglutinin were more effective than either the single-component or two-component vaccines.

Child, Preschool↗
PubMed1997

Clinical findings in Bordetella pertussis infections: results of a prospective multicenter surveillance study.

OBJECTIVE: To study the clinical presentation of culture-confirmed pertussis in children and their contacts with cough illnesses in an outpatient setting. METHODOLOGY: In conjunction with a large pertussis vaccine efficacy trial in Germany, a central laboratory to isolate Bordetella species from nasopharyngeal specimens was established in Erlangen in October 1990. Pediatricians in private practices in southern Germany, the Saar region, and Berlin were encouraged to obtain nasopharyngeal specimens and clinical characteristics from patients with cough illnesses >/=7 days' duration. Bordetella species were isolated by use of calcium alginate swabs, Regan-Lowe agar, and modified Stainer-Scholte broth. Clinical characteristics were determined by initial and follow-up questionnaires. RESULTS: From October 1990 to September 1996, 20 972 specimens were submitted, and B pertussis was isolated in 2592 instances (12.4%). Of the culture-proven cases, 50.7% were female, and the age range was 6 days to 41 years, with a mean and median of 4.3 years and 4.1 years, respectively. The following characteristics were noted. Only 4% of the patients had received pertussis vaccine. Of unvaccinated patients, 90.2% had paroxysmal cough, 78.9% demonstrated whooping, and 53.3% presented with posttussive vomiting; 5.7% had fever >/=38 degrees C. The duration of cough was </=4 weeks in 37.9% and </=3 weeks in 17.4%. Leukocytosis and lymphocytosis (values above the age-specific mean) were observed in 71.9% and 75.9% of unvaccinated patients, respectively. The overall complication rate was 5.8%, and pneumonia (29%) was the most frequent complication. In infants <6 months of age, the rate of complications was 23.8%. One death in a 7-month-old infant occurred. CONCLUSIONS: Typical symptoms of pertussis were observed in the great majority of patients regardless of age group. However, the duration of cough was surprisingly short in one sixth of the patients. These short illness cases would not be classified as pertussis according to the World Health Organization clinical case definition, which requires >/=21 days of spasmodic cough.

Adolescent↗
PubMed1997

The risk of Guillain-Barré syndrome after tetanus-toxoid-containing vaccines in adults and children in the United States.

OBJECTIVES: This study examined whether there is a risk that tetanus-toxoid-containing vaccines could cause Guillain-Barré syndrome and, if so, how large the risk is. METHODS: This study was based on previous active surveillance epidemiological studies of Guillain-Barré syndrome and vaccination history. RESULTS: A background rate of 0.3 cases of Guillain-Barré syndrome per million person-weeks has been estimated. By chance, 2.2 people with the syndrome would have received tetanus-toxoid-containing vaccine within the 6 weeks before onset, yet only 1 person had done so. Data on children show similar results. CONCLUSIONS: If an association exists, it must be extremely rare and not of public health significance.

Adult↗
PubMed1997

Severe adverse events in a comparative efficacy trial in Germany in infants receiving either the Lederle/Takeda acellular pertussis component DTP (DTaP) vaccine, the Lederle whole-cell component DTP (DTP) or DT vaccine. The Pertussis Vaccine Study Group.

Severe adverse events were evaluated in a comparative efficacy trial in Germany in infants who received either the Lederle/Takeda acellular pertussis component DTP (DTaP) vaccine, the Lederle whole-cell component DTP (DTP) or DT vaccine. Vaccinees received four doses (at three, four-and-a half, six and 15-18 months of age) of either DTP or DTaP vaccine or three doses at three, four-and-a half and 15-18 months of age) of DT vaccine. The analysis included 4,273 DTaP recipients, 4,259 DTP recipients and 1,739 DT vaccinees. Convulsions within three days of vaccination occurred in 1/15,912 doses in DTaP recipients and 1/3,926 doses in DTP vaccinees (p = 0.22). Persistent inconsolable crying was more common in DTP vaccinees (1/113 doses) compared with DTaP (1/497 doses, p < 0.001) and DT (1/359 doses, p < 0.001) recipients. High fever (< or = 40.5 degrees C) was less frequent in DTaP vaccinees (1/16,239 doses) compared with DTP (1/5,359) and DT recipients (1/4,665). One hypotonic-hyporesponsive episode was observed.

Cohort Studies↗
PubMed1997

Minor adverse events in a comparative efficacy trial in Germany in infants receiving either the Lederle/Takeda acellular pertussis component DTP (DTaP) vaccine, the Lederle whole-cell component DTP (DTP) or DT vaccine. The Pertussis Vaccine Study Group.

Minor adverse events were evaluated in a comparative efficacy trial in Germany in infants who received either the Lederle/Takeda acellular pertussis component DTP (DTaP) vaccine, the Lederle whole-cell component DTP (DTP) or DT vaccine. Vaccinees received four doses (at three, four-and-a half, six and 15-18 months of age) of either DTP or DTaP vaccine or three doses (at three, four-and-a half and 15-18 months of age) of DT vaccine. The reactogenicity analysis included 4,273 DTaP, 4,259 DTP and 1739 DT vaccinees. Local reactions (erythema and induration) and systemic events (fever, fretfulness, drowsiness and anorexia) were more common after each dose of DTP vaccine than after the DTaP and DT vaccine doses. Erythema, induration and fever increased in frequency in DTaP and DT recipients with increasing series number. Erythema, induration and fever after the first two doses of vaccine were more frequent in DT recipients than DTaP vaccinees. Antipyretics were more commonly used in DTP recipients than in DTaP vaccinees.

Cohort Studies↗
PubMed1997

The role of Bordetella pertussis infections in adults in the epidemiology of pertussis.

In six of the seven efficacy studies, cases of pertussis in adults were diagnosed. In particular, primary cases in adults were common in study families in the Mainz and Erlangen studies. Recent epidemiological studies indicate that B. pertussis infections in adults are common and endemic. It is suggested that B. pertussis circulation cannot be controlled by immunization of children but that acellular vaccines make it possible to give booster immunizations to adults. An adult booster programme might decrease the circulation of B. pertussis in adults and could lead to the elimination of the organism from the population.

Adult↗
PubMed1996

Transmission of hepatitis B virus to multiple patients from a surgeon without evidence of inadequate infection control.

BACKGROUND: Although about 1 percent of surgeons are infected with hepatitis B virus (HBV), transmission from surgeons to patients is thought to be uncommon. In July 1992, a 47-year-old woman became ill with acute hepatitis B after undergoing a thymectomy in which a thoracic-surgery resident who had had acute hepatitis B six months earlier assisted. METHODS: To determine whether the surgeon transmitted HBV to this patient and others, we conducted chart reviews, interviews, and serologic testing of thoracic-surgery patients at the two hospitals where the surgeon worked from July 1991 to July 1992. Hepatitis B surface antigen (HBsAg) subtypes and DNA sequences from the surgeon and from infected patients were determined. RESULTS: Of 144 susceptible patients in whose surgery the infected surgeon participated, 19 had evidence of recent HBV infection (13 percent). One of the hospitals was selected for additional study, and none of the 124 susceptible patients of the other thoracic surgeons at this hospital had evidence of recent HBV infection (relative risk, infinity; 95 percent confidence interval, 4.7 to infinity). No evidence was found for any common source of HBV other than the infected surgeon. The HBsAg subtype and the partial HBV DNA sequences from the surgeon were identical to those in the infected patients. Transmission of the infection was associated with cardiac transplantation (relative risk, 4.9; 95 percent confidence interval, 1.5 to 15.5) but not with other surgical procedures. The surgeon was positive for hepatitis B e antigen and had a high serum HBV DNA concentration (15 ng per milliliter). Our investigations identified no deficiencies in the surgeon's infection-control practices. CONCLUSIONS: In this outbreak there was surgeon-to-patient HBV transmission despite apparent compliance with recommended infection-control practices. We could not identify any specific events that led to transmission.

Adolescent↗
PubMed1996

Bordetella pertussis infections and sudden unexpected deaths in children.

UNLABELLED: From December 1990 to November 1993 nasopharyngeal specimens were obtained for culture from 50 children (mean 4.9 +/- 3.3 months of age) who had died suddenly. Bordetella pertussis was not isolated. Subsequently, nasopharyngeal specimens for polymerase chain reaction (PCR) analysis were obtained from another 51 victims of sudden death (mean 5.4 +/- 4.4 months of age); nine (18%) were B. pertussis positive. CONCLUSION: Our findings support previous epidemiological studies which noted an association between epidemic pertussis and sudden infant death syndrome. Further PCR studies with both internal and external controls should be performed.

Cell Culture Techniques↗
PubMed1996

A search for persistent rubella virus infection in persons with chronic symptoms after rubella and rubella immunization and in patients with juvenile rheumatoid arthritis.

Peripheral blood polymorphonuclear leukocytes, mononuclear cells, and plasma and nasopharyngeal specimens were obtained from 6 subjects with persistent symptoms following rubella immunization, 1 subject with persistent symptoms following rubella, 11 children with juvenile rheumatoid arthritis, 17 recently immunized control subjects, and 1 control subject with acute clinical rubella. Rubella virus was isolated from the blood or nasopharynx of four of the 18 control subjects. In contrast, rubella virus was not recovered from any specimens from the seven subjects with persistent symptoms following immunization or natural infection or from the 11 children with juvenile rheumatoid arthritis. A polymerase chain reaction assay detected rubella virus in the blood from three of 14 control subjects but not in the blood from two subjects with persistent symptoms following rubella immunization or in that from three children with juvenile rheumatoid arthritis. We have not been able to confirm the findings of others who have reportedly recovered rubella virus from lymphocytes of persons with persistent symptoms following rubella or rubella immunization.

Adolescent↗
PubMed1996

Historical review of pertussis and the classical vaccine.

Pertussis is an epidemic disease caused by Bordetella pertussis and also to a lesser extent by Bordetella parapertussis. Classical illness lasts 4-8 weeks and is characterized by paroxysms of coughing with posttussive vomiting and whooping; however, 47.4% of primary infections last 4 weeks or less. Whole cell pertussis vaccines are generally highly efficacious. All whole cell vaccines are reactogenic, causing fever and local reactions in many vaccinees. In the past, these vaccines were thought to cause infant deaths and brain damage. However, several large epidemiologic studies indicate that whole cell vaccines do not cause infant deaths or neurologic disease. Recent studies indicate that neither immunization nor infection give long-term immunity. As a result, B. pertussis infections are endemic in adult populations. The future control of B. pertussis will require immunization schedules with new acellular vaccines that include booster doses in older children and adults.

History, 16th Century↗
PubMed1996

Risk factors of infantile spasms compared with other seizures in children under 2 years of age.

To analyze the magnitude of the risk factors for infantile spasms, we evaluated the records of 80 children with infantile spasms, 474 children with other types of epilepsy, 2,196 children with febrile seizures, and 262 children with CNS infections. There was a family history of seizures in 13.8% of children with infaNtile spasms, 28.5% of children with other forms of epilepsy, 25.5% of children with febrile seizures, and 5.3% of children with CNS infections. Children with a family history of seizures were 2.82 times more likely to have infantile spasms, 7.05 time more likely to have other epilepsy, and 6.08 time more likely to have febrile seizures than controls (children with CNS infections). However, a family history of seizures increased the risk for infantile spasms only in the cryptogenic group. Children with infantile spasms were significantly more likely to have cerebral palsy, microcephaly, hydrocephaly, CNS malformations, neonatal hypoxia, or neonatal seizures than children with other types of epilepsy, febrile seizures, or CNS infections. There was a modest genetic predisposition to seizures in children with infantile spasms. However, our data suggest a much stronger association with underlying neurologic abnormalities, mainly neonatal seizures, neonatal hypoxia, and CNS malformations.

Age Factors↗
PubMed1996

Analysis of proteins encoded by the ptx and ptl genes of Bordetella bronchiseptica and Bordetella parapertussis.

Bordetella pertussis is the only bacteria] species which is known to produce pertussis toxin (PT); however, both Bordetella bronchiseptica and Bordetella parapertussis contain regions homologous to the ptx genes of B. pertussis that encode the toxin subunits. After finding that several children with B. parapertussis infections exhibited modest antibody titers to PT, we examined the ptx genes of both B. parapertussis and B. bronchiseptica to determine whether they would encode stable, functional proteins even though their promoters are thought to be inactive under the conditions that have been examined. We inserted a functional promoter directly upstream of the ptx-ptl region of both species and examined culture supernatants of the resulting strains for PT activity. Biologically active PT was found in the culture supernatants of both engineered species. The toxin encoded by the B. parapertussis ptx genes appeared more labile in culture supernatants than did toxin produced by either B. pertussis or the engineered strain of B. bronchiseptica. This lability might be due to the lack of a full-length S2 subunit. We also investigated the ptl genes of these species, which are necessary for the secretion of this toxin, and found that both B. bronchiseptica and B. parapertussis contain at least certain of these genes, including ptlE and ptlF. Moreover, B. bronchiseptica appeared to contain all essential ptl genes since the introduction of a functional promoter directly upstream of the ptx-ptl region resulted in both production and efficient secretion of toxin. These results indicate that despite a number of amino acid changes in the sequences of the toxins, the toxins encoded by B. bronchiseptica and B. parapertussis are active.

Animals↗
PubMed1995

Risk factors of respiratory failure in children with Guillain-Barré syndrome.

Recently it was found that plasmapheresis and intravenous immunoglobulins are effective in treating patients with Guillain-Barré syndrome (GBS). However, these treatments are expensive and not without possible adverse effects. Because signs and symptoms predictive for respiratory failure in GBS would be helpful in targeting the treatment, risk factors for respiratory failure were evaluated in 120 children with GBS. Twenty children required assisted ventilation. None of the children without any of the following risk factors had respiratory failure. If the symptoms of GBS began within 8 days after a preceding infection, the odds ratio (OR) for respiratory failure was 4.9 [95% confidence intervals (CI): 1.3-18.5]. Cranial nerve involvement was more common in children who required assisted ventilation (15/20 versus 32/100, OR: 6.4, 95% CI: 2.1-19.1). A cerebrospinal protein level > 800 mg/L during the first week had an OR for assisted ventilation of 3.1 (95% CI of OR: 1.04-9.0). In the logistic multivariate model, all of these risk factors were associated with the need for assisted ventilation. On the basis of our findings, preventive treatment with either plasmapheresis or intravenous immunoglobulins could be directed to those children with any of the risk factors; for those patients without the risk factors, clinical monitoring would be satisfactory.

Child↗