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Concerns about vaccine safety make some parents hesitant about immunization. Health care providers are pivotal in helping parents understand that Canada is a leader in vaccine safety. The present practice point provides an update on the eight components of Canada's vaccine safety system: (1) an evidence-based pre-license review and approval process; (2) strong regulations for manufacturers; (3) independent evidence-based vaccine use recommendations; (4) immunization competency training and standards for health care providers; (5) pharmacovigilance programs to detect and (6) determine causality of adverse events following immunization (AEFIs); (7) a program for vaccine safety and efficacy signal detection; and (8) the Canadian Immunization Research Network's special immunization clinics for children who have experienced serious AEFIs.

Targeted Bacille Calmette-Guérin (BCG) vaccination is offered to neonates in some First Nations and Inuit (FNI) communities in Canada. Serious adverse events associated with BCG vaccine prompted a review to assess causality.

Prematurity is a proven risk factor for severe respiratory syncytial virus (RSV) infection. Prematurity leads to an increased need for, and duration of, hospital admission, intensive care, mechanical ventilation and supplemental oxygen, as well as increased mortality.

Infants born at 33 through 35 completed weeks of gestation (33-35GA) are at risk for severe respiratory syncytial virus (RSV) infection, and palivizumab prophylaxis lowers hospitalizations for RSV infection by as much as 80%. The 33-35GA cohort comprises 3-5% of annual births; thus expert panels recommend limiting prophylaxis to situations in which frequency or health care impact of RSV infection is high. This study sought to identify independent risk factors for hospitalization for RSV infection.

After licensing of a varicella vaccine in Canada in 1998, Health Canada commissioned a study to evaluate options for a vaccination program. The evaluation of a program of vaccination of 12-month-old children, with and without a catch-up program for susceptible 12-year-olds, is presented here.

We wished to compare outcomes of respiratory syncytial virus (RSV) infection in children with bronchopulmonary dysplasia (BPD) with those with other pulmonary disorders: cystic fibrosis, recurrent aspiration pneumonitis, pulmonary malformation, neurogenic disorders interfering with pulmonary toilet, and tracheoesophageal fistula.

A model of overwhelming E. coliK1 sepsis and early meningitis was developed in infant rabbits and used to compare clinical and bacteriologic efficacy of ampicillin, moxalactam, cephalothin and chloramphenicol. Intraperitoneal injection of 107E. coliK1 into 1- or 2-wk-old rabbits produced a rapidly progressive infection which, if left untreated, produced bacteremia in 100 of animals, meningitis in 78, and mortality in 100. Therapy was initiated 4 h after ip infection at which time mean bacterial concentration (log10CFU/ml) ranged from 4.4-4.8 in the blood and from 1.8- 2.3 in the cerebral spinal fluid (CSF). Pre-treatment frequency of bacteremia (100) and meningitis (17-23) was similar for all experimental groups. Antibiotic concentrations in blood and CSF 2 h after a dose exceeded the E. coliminimum inhibitory concentration with the exception of CSF cephalothin, which was undetectable. Moxalactam, ampicillin, and chloramphenicol significantly reduced the incidence of bacteremia and meningitis relative to cephalothin or saline controls (P< 0.02). Mortality rates among the former three groups were high (64-82) but significantly less than in saline or cephalothin-treated rabbits (100). In this neonatal model of fulminant sepsis with early meningitis, moxalactam provided no therapeutic advantage over ampicillin or chloramphenicol.

Objectives:To quantify the cost and distribution of health care resources consumed annually in management of Canadian children from birth to 4 years of age with respiratory syncytial virus (RSV) infection.

To determine the total and functional serogroup C antibody response to a quadrivalent meningococcal polysaccharide vaccine in a group of aboriginal infants, children and adolescents. A secondary objective was to determine their prevalence of meningococcal carriage.

Respiratory syncytial virus (RSV) is the most frequent cause of hospitalization for respiratory tract infection during the first 2 years of life. The optimal approach to management remains controversial. During the 1991 to 1992 RSV season RSV-infected children admitted to eight Canadian tertiary care pediatric centers were followed to: (1) assess the morbidity and mortality attributable to RSV infection among hospitalized patients with and without known risk factors for severe disease; and (2) assess regional variation in the management of RSV infection. Of 529 RSV-infected patients 69 (363) had one or more of the risk factors for severe disease and the remaining 31 (166) had none. There were significant differences (P≤ 0.01) between the high and low risk groups, respectively, for: intensive care unit admission (27, 2), assisted ventilation (14, 0.6), ribavirin therapy (20, 2), supplemental oxygen (75, 34), antibiotic therapy (69, 58) and length of hospital stay ≥ 7 days (39, 6). Among low risk patients, centers varied significantly (P≤ 0.01) in the use of systemic corticosteroids (from 3 to 69 of patients), supplemental oxygen (13 to 74), bronchodilators (68 to 93) and ribavirin (0 to 10). The observed regional variation in management of hospitalized children with RSV infection has implications for both the costs of hospital care and the conduct of multicenter trials of ribavirin and other therapies for RSV infection.

OBJECTIVES:To describe differences in patients hospitalized with respiratory syncytial virus (RSV) lower respiratory tract infection (LRI) at nine Canadian tertiary care hospitals. In addition, this study describes the variation in use of drug and other interventions. METHODS:Data on patients hospitalized with RSV LRI and their outcomes were prospectively collected. Demographic data were obtained on enrollment by center study nurses. Data recorded daily included clinical assessment, oxygen saturation determination, and interventions (bronchodilators, steroids, ribavirin, antibiotics, intensive care, and mechanical ventilation) received during the day. Patients were divided into those with underlying diseases including congenital heart disease, chronic lung disease, immunodeficiency, or multiple congenital anomalies and those who were previously healthy. Mean RSV-associated length of stay and the proportion of patients receiving each intervention in each group were determined by hospital. RESULTS:A total of 1516 patients were enrolled at nine hospitals during January 1 to June 30, 1993, and January 1 to April 30, 1994. Significant differences were observed among hospitals in the proportion of patients with underlying disease, postnatal age less than 6 weeks, hypoxia, and pulmonary infiltrate on chest radiograph. The mean length of stay varied among hospitals from 8.6 to 11.8 days and 4.6 to 6.7 days in compromised and previously healthy patients, respectively. Except for receipt of bronchodilators, compromised patients were significantly more likely to receive interventions than previously healthy patients. There was variation among hospitals in receipt of most interventions in compromised and previously healthy patients. This variation was statistically significant for previously healthy patients but not statistically significant in those with underlying disease, because the numbers of patients in the latter group were much smaller. The magnitude of the variation for each intervention, however, was not different between those with underlying disease compared with previously healthy patients. CONCLUSION:Differences exist among tertiary pediatric hospitals in the nature of the patients admitted with RSV LRI. Variation occurred in the use of five interventions among the hospitals, regardless of whether the patient had underlying illness or was previously healthy. Given their current widespread use, high cost, and potential side effects, randomized clinical trials are needed to determine the efficacy of different drug treatments used to treat infants hospitalized with RSV. (J PEDIATR1996;129:390-5)

Summary: A model of overwhelming E. coli K1 sepsis and early meningitis was developed in infant rabbits and used to compare clinical and bacteriologic efficacy of ampicillin, moxalactam, cephalothin and chloramphenicol. Intraperitoneal injection of 107E. coli K1 into 1-or 2-wk-old rabbits produced a rapidly progressive infection which, if left untreated, produced bacteremia in 100% of animals, meningitis in 78%, and mortality in 100%. Therapy was initiated 4 h after ip infection at which time mean bacterial concentration (log10CFU/ml) ranged from 4.4-4.8 in the blood and from 1.8-2.3 in the cerebral spinal fluid (CSF). Pre-treatment frequency of bacteremia (100%) and meningitis (17-23%) was similar for all experimental groups. Antibiotic concentrations in blood and CSF 2 h after a dose exceeded the E. coli minimum inhibitory concentration with the exception of CSF cephalothin, which was undetectable. Moxalactam, ampicillin, and chloramphenicol significantly reduced the incidence of bacteremia and meningitis relative to cephalothin or saline controls (P < 0.02). Mortality rates among the former three groups were high (64-82%) but significantly less than in saline or cephalothin-treated rabbits (100%). In this neonatal model of fulminant sepsis with early meningitis, moxalactam provided no therapeutic advantage over ampicillin or chloramphenicol.

Concerns about vaccine safety make some parents hesitant about immunization. Health care providers are pivotal in helping parents understand that Canada is a leader in vaccine safety. The present practice point provides an update on the eight components of Canada's vaccine safety system: (1) an evidence-based pre-license review and approval process; (2) strong regulations for manufacturers; (3) independent evidence-based vaccine use recommendations; (4) immunization competency training and standards for health care providers; (5) pharmacovigilance programs to detect and (6) determine causality of adverse events following immunization (AEFIs); (7) a program for vaccine safety and efficacy signal detection; and (8) the Canadian Immunization Research Network's special immunization clinics for children who have experienced serious AEFIs.

Diphtheroids — Corynebacterium species other than C diphtheriae—are ubiquitous organisms and rarely pathogenic. When isolated in cultures of blood and other usually sterile body sites, diphtheroids are commonly dismissed as contaminants.1 In 1978, diphtheroids accounted for 3.2% of positive blood cultures and grew from 0.2% of all blood cultures (4,000) at the Montreal Children's Hospital (MCH).A child, recently hospitalized at the MCH for evaluation of fever of unknown origin, was discharged without a diagnosis. The growth of diphtheroids in two of seven blood cultures was dismissed as unimportant because the child did not seem to be a compromised host and no apparent nidus of infection could be found. Subsequent events proved that these diphtheroids were the cause of his illness. The purpose of this report is to encourage the critical evaluation of all isolates from normally sterile sites such as blood, CSF, and bone marrow.Report of

Administration of antibody to Escherichia coli strain 15 reduces mortality in patients with gram-negative septic shock. Limited evidence suggests that this antibody is present in the serum of healthy individuals and deficient in persons with malignancy; however, the age-related prevalence of serum antibody to strain 15 in normal subjects is unknown. We developed an ELISA method to measure IgG and IgM antibody to purified 15 lipopolysaccharide (LPS) in sera from 33 maternal-newborn cord pairs, 40 neonates, and 253 individuals aged from one day to twenty years. Reciprocal geometric mean titers for serum antibody to strain 15 LPS were as follows: maternal-IgG, 12.3; IgM, 174; one month old or less-IgG, 8.3; IgM, 5.6; one to 24 months old —IgG, 10.5; IgM, 44.7; >24 months old — IgG, 16.2; IgM, 200. Weconclude that human serum antibody to 15 LPS is predominantly IgM and that it is usually present by two years of age. The ELISA method should provide a valuable tool in studying the relation of core glycolipid antibody to immunity and therapy of gram-negative bacterial infections.