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S Halperin

Publications and source records attributed to S Halperin.

At least 19 recordsLinked to original sources
PubMed2002

Pertussis of adults and infants.

Bordetella pertussis continues to circulate even in populations where a high vaccine coverage of infants and children is achieved. Cases in adolescents and adults are reported with increasing frequency in many countries. Adults are a reservoir for infections in very young infants, in whom pertussis may be severe and life-threatening. The salient clinical feature of pertussis in adolescents and adults is prolonged coughing, and recognising that pertussis does occur in these age groups is the most important step in its diagnosis. A laboratory diagnosis can be made by bordetella-PCR from nasopharyngeal swabs or secretions and by detection of antibodies, mainly to pertussis toxin; laboratory diagnosis is, however, not well standardised. Vaccination of adolescents and adults is now possible with acellular pertussis vaccines, which are well tolerated, immunogenic, and effective. Adolescent boosters and the vaccination of health-care workers are already included in vaccination calendars in some countries. Vaccine-recommending bodies and national health-care organisations must have locally relevant information on the transmission of pertussis from adults to infants to be able to make decisions on the advisability, feasibility, and priority for booster immunisation against pertussis.

Adult↗
PubMed2001

Recommendations are needed for adolescent and adult pertussis immunisation: rationale and strategies for consideration.

Pertussis vaccination of infants has dramatically reduced disease, complications and deaths in infancy and early childhood. But there is still a major public health challenge--to deal with the morbidity and economic burden of illness in older children, adolescents and adults. Furthermore, it is these groups that form a major source of infection for non-immunised and partially immunised infants who are at high risk of severe complications. Adult-type acellular pertussis vaccine confers safe and effective protection against pertussis. There are several strategies to consider for immunising older individuals. Universal vaccination of all age groups would be the best available strategy for protecting individuals. It would also reduce the potential for transmitting the disease to other susceptibles, particularly infants. However, such a policy may be difficult both logistically and economically at this time. More easily achievable as a first step would be a strategy of universal adolescent booster vaccination combined with a programme targeted at adults most likely to have contact with very young babies including healthcare and childcare workers, parents and close family contacts. There is also potential for offering vaccination to adults (and their carers and close contacts) whose medical conditions or advanced age may place them at increased risk of more severe pertussis disease. Specific details of immunisation programmes must be made on a country by country basis depending on local circumstances.

Adolescent↗
PubMed2000

Invasive pneumococcal infections in Canadian children, 1991-1998: implications for new vaccination strategies. Canadian Paediatric Society/Laboratory Centre for Disease Control Immunization Monitoring Program, Active (IMPACT).

We reviewed 2040 consecutive cases of invasive pneumococcal infection that were seen at 11 pediatric centers across Canada during 1991-1998 to determine if such infections could be prevented by new conjugate vaccines. Isolates from 1528 cases were serotyped. Most cases (61.5%) occurred in patients aged >2 years. Underlying medical conditions were present in 23.2% of case patients. Serotypes in the 7-valent conjugate vaccine matched isolates as follows: 85.8% of tested isolates from children aged 6 months to 5 years, but significantly fewer isolates in younger and older children; 72.9% of isolates from non-healthy children, but 83.9% of isolates from previously healthy children; and 95.4% of isolates with high-level penicillin resistance, but only 72.7% of those with intermediate-level resistance. Significant natural variation in the proportion of isolates matching 7-valent vaccines occurred from year to year and among centers. New conjugate vaccines have great potential but their effectiveness and limitations require ongoing study.

Bacteremia↗
PubMed2000

A cognitive-behavioural, group-based intervention for social anxiety in schizophrenia.

OBJECTIVE: The objective of this study was to investigate the efficacy of group-based cognitive-behavioural therapy (CBT) for social anxiety in schizophrenia. METHOD: Patients with schizophrenia (20) with comorbid social anxiety were randomly assigned to the group-based CBT or wait-list control condition. Pre-, post- and 6-week follow-up ratings included measures of social anxiety and avoidance, mood and quality of life. RESULTS: The intervention group improved on all outcome measures and the control group showed no change in symptomatology. CONCLUSIONS: Group-based CBT is effective in treating social anxiety in schizophrenia.

Adult↗
PubMed2000

The Immunization Monitoring Program Active (IMPACT) prospective five year study of Canadian children hospitalized for chickenpox or an associated complication.

BACKGROUND: Varicella vaccine was approved for use in Canada in 1998. A major goal of universal varicella vaccine programs is to reduce severe infection and associated complications. Baseline data are essential against which to judge the effectiveness of routine childhood immunization. OBJECTIVE: To describe morbidity and mortality among children hospitalized for chickenpox. Methods. From January 1, 1991, to March 31, 1996, chickenpox admissions to 11 pediatric referral centers were actively identified. Patient and illness characteristics were compared for 3 subgroups defined by prior health: healthy; unhealthy but immunocompetent; immunocompromised. RESULTS: Of 861 cases 488 (56.7%) were healthy, 75(8.7%) were unhealthy and 298 (34.6%) were immunocompromised. The immunocompromised children differed from healthy/unhealthy cases in mean age (6.4 vs. 4.0/4.6 years, respectively, P < 0.0001); median interval from rash onset to admission (2 vs. 5/5 days, P < 0.0001); complication rate (20% vs. 90%/79%; P = 0.001); and rate of acyclovir therapy (98% vs. 24%/39%; P = 0.001). Unhealthy vs. healthy cases had a higher frequency (P < 0.01) of intensive care (13.3% vs. 4.7%), ventilation (9.3% vs. 2.0%) and death (4% vs. 0.2%). CONCLUSION: These data provide a baseline for morbidity/mortality resulting from chickenpox before varicella vaccine use in Canada.

Adolescent↗
PubMed1999

Failure of physicians to consider the diagnosis of pertussis in children.

To determine the ability of physicians to make a diagnosis of pertussis and factors associated with improved diagnosis, 8,235 children from 88 child care centers and 14 elementary schools from Quebec City, Quebec, Canada, were evaluated by using a questionnaire completed by parents and a medical record review. Children must have consulted a physician to be included in the evaluation. There were 558 children meeting the surveillance case definition and 416 meeting a modified World Health Organization case definition who consulted a physician. A diagnosis of pertussis was considered in 24%-26% of children meeting either case definition, made in 12%-14%, and reported for 6%. Pertussis diagnosis was significantly associated with having a history of pertussis exposure (P < or = .003), four pertussis-related symptoms (P < .001), and a cough for > or = 5 weeks (P < or = .05) and consulting in a hospital setting (P < or = .03). The proportion of cases of pertussis diagnosed and reported is low even when children present with classical symptoms.

Adult↗
PubMed1999

Treatment of severe pertussis: a study of the safety and pharmacology of intravenous pertussis immunoglobulin.

BACKGROUND: Pertussis in infants is often severe, resulting in complications and prolonged hospitalization. Treatment is limited to supportive care. Antibiotics do not significantly alter the course of the disease. Therapies directed at pertussis toxin, a major virulence factor of Bordetella pertussis, might be beneficial. This study examines the safety and pharmacology of intravenous pertussis immunoglobulin (P-IGIV), which has high levels of pertussis toxin antibodies. METHODS: P-IGIV was prepared as a 4% IgG solution from the pooled plasma from donors immunized with inactivated pertussis toxoid. The IgG pertussis toxin antibody concentration of 733 microg/ml is >7-fold higher than contained in conventional intravenous immunoglobulin products. Children with presumptive pertussis were allocated to one of three treatment doses of P-IGIV. RESULTS: Twenty-six of 30 enrolled children had confirmed pertussis. There were no adverse events associated with P-IGIV except one patient who had transient hypotension that responded to an infusion rate decrease. P-IGIV doses of 1500, 750 and 250 mg/kg achieved > or =4-fold, 3-fold and >2-fold rises in peak geometric mean titers of pertussis toxin IgG antibodies, respectively. P-IGIV exhibited a half-life of 38.4 days and a volume of distribution of 87.8 ml/kg. All three treatment groups showed declines in lymphocytosis (P < 0.05) and paroxysmal coughing by the third day after P-IGIV infusion compared with preinfusion values. CONCLUSION: P-IGIV is safe and achieves high pertussis toxin antibody titers in infants. This study provides data for a prospective, controlled trial of P-IGIV.

Antibodies, Bacterial↗
PubMed1999

Cost of chickenpox in Canada: part I. Cost of uncomplicated cases.

OBJECTIVE: The purpose of this study was to assess the direct medical costs and productivity losses associated with uncomplicated chickenpox (no hospitalization) in Canada. METHODS: A total of 179 otherwise healthy 1- to 9-year-old children with active chickenpox were recruited from schools, day care centers, and physician offices in 5 provinces. Direct medical (physician contacts, medication, and diagnostic tests) and nonmedical (personal expenses including child care) resources expended during the illness were determined by caregiver interview. Productivity losses attributable to the disease were determined by assessing caregiver time lost from work and daily activities. Unit costs for all resources were obtained from sources in 2 provinces, and per-patient treatment costs were determined from the patient, Ministry of Health, and societal perspectives. RESULTS: From a societal perspective, the per-case cost for children from 1 to 4 years of age and from 5 to 9 years of age was $370.2 and $236.5, respectively. Direct medical costs accounted for 10% of the total costs in both groups. The largest cost driver in patient care was caregiver productivity losses, which amounted to $316.5 in the younger age group and to $182.7 in the older age group. Based on an estimated yearly incidence of 344 656 cases of uncomplicated chickenpox in Canada, the total annual societal burden of the disease can be estimated at $109.2 million, with a cost to the Ministry of Health of $11.2 million. CONCLUSION: Chickenpox is one of the last common childhood diseases prevalent in Canada, and the uncomplicated disease, despite its rather benign course, imparts a large annual economic burden.

Canada↗
PubMed1996

Effectiveness of a whole cell pertussis vaccine in child-care centers and schools.

BACKGROUND: Pertussis has substantially increased in Quebec, Canada, since 1990. We estimated pertussis vaccine effectiveness and vaccine coverage in child-care centers and elementary schools. METHODS: Two retrospective cohort studies were simultaneously conducted. One included 4482 children attending 88 public child-care centers and the other included 3429 pupils in 14 elementary schools. Cough and pertussis symptoms were assessed through a questionnaire and medical records; immunization status was ascertained by examination of written records. RESULTS: In child-care centers 95% of children had received at least three vaccine doses at the beginning of the follow-up; in schools more than 98% of pupils had received at least 4 doses. With > or = 4 doses of vaccine and a standard case definition used for surveillance (cough > or = 2 weeks, > or = 1 pertussis symptom and no other apparent cause for cough), vaccine effectiveness was estimated at 61% (95% confidence interval, 44 to 72%) in child-care centers and at 60% (95% confidence interval, 10 to 82%) in schools. With the same number of doses but a case definition requiring a cough > or = 5 weeks, vaccine effectiveness increased to 71% (95% confidence interval, 49 to 83) in child-care centers and to 86% (95% confidence interval, 66 to 94%) in schools. CONCLUSIONS: The increase in pertussis in Quebec is not caused by a low vaccine coverage. A low vaccine effectiveness may contribute to the resurgence of pertussis in the past decade.

Canada↗
PubMed1995

Clinical course of pertussis in immunized children.

To describe the clinical course of Bordetella pertussis infection in a highly immunized childhood population, we studied prospectively endemic and epidemic pertussis in a metropolitan population with an immunization rate > 90% during an 8-year period from 1987 through 1994. Patients with a possible diagnosis of pertussis were referred by family or emergency room physicians for nasopharyngeal culture. Patients with a culture positive for B. pertussis were contacted by a nurse who completed a detailed questionnaire for the index case and all family members. Repeat home visits were made each week for 4 weeks. Of the 189 patients with pertussis who were evaluated 103 subjects were < 5 years of age. Congestion predated the onset of cough by up to 1 week in 35 (34%) cases. Seventy (68%) subjects < 5 years of age developed a paroxysmal cough within the first week of their illness. Ninety-one (88%) cases < 5 years old had a persistent paroxysmal cough for > 21 days. Coughing in this group lasted from 16 to 91 days (median 48). Erythromycin therapy appeared to shorten the duration of cough; however, patients were not randomized to receive erythromycin at a specific time. Despite adequate immunization some children develop pertussis. The clinical course in these patients is milder than in unimmunized subjects. Nevertheless the symptomatology in these children should still be readily identified by most physicians using classical clinical criteria of pertussis.

Anti-Bacterial Agents↗