Distribution and clinical impact of human respiratory syncytial virus genotypes in hospitalized children over 2 winter seasons.

Sequencing studies of the glycoprotein G gene were performed in human respiratory syncytial virus (hRSV) strains detected by reverse-transcription polymerase chain reaction directly from nasopharyngeal aspirates of hospitalized children < or =3 years old over 2 winters. Clinical data were compared between 106 children infected with group A hRSV (96 GA2 genotypes) and 94 children infected with hRSV group B (62 GB3 genotypes). A severity index was defined by assigning 1 point each for the use of >30% supplemental oxygen, admission to an intensive-care unit, and duration of hospital stay of >5 days.

Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review.

Background: In Canada--a low endemicity country, vaccines for hepatitis A virus (HAV) are currently recommended to individuals at increased risk for infection or its complications. Applying these recommendations is difficult because the epidemiology of HAV infection is poorly defined, complex, and changing. This systematic review aimed to 1) estimate age-specific prevalence of HAV antibody in Canada and 2) evaluate infection-associated risk factors.

Immunogenicity of two paediatric doses of monovalent hepatitis B or combined hepatitis A and B vaccine in 8-10-year-old children.

Hepatitis A and B vaccines are highly immunogenic in three-dose schedules. To obtain an equivalent result in children with two paediatric doses would be of significant benefit. The purpose of this study was to measure the immunogenicity of a two-dose schedule in children with two licensed recombinant HBsAg containing vaccines given at paediatric doses, one of them combined with hepatitis A.

Nationwide canadian study of hepatitis a antibody prevalence among children eight to thirteen years old.

Background: Hepatitis A vaccines provide consistent, long-lasting protection and have been available for almost 10 years in Canada, but their use remains limited. It is difficult to assess their optimal utilization given that our knowledge of hepatitis A epidemiology in Canada is fragmentary. Unlike the United States, no nationwide study of hepatitis A prevalence has ever been done in Canada.

Oculo-respiratory syndrome after influenza vaccination: trends over four influenza seasons.

Background: Oculo-respiratory syndrome (ORS) following influenza vaccination was identified in Canada in 2000. This report describes trends of ORS reported during four consecutive seasons 2000, 2001, 2002 and 2003 in the province of Quebec, Canada.

Methods: Data come from the vaccine-associated adverse event (VAAE) passive reporting system of the Province of Quebec.

Economic evaluation of an extended acellular pertussis vaccine program for adolescents in Québec, Canada.

Objective: Pertussis is a frequent cause of cough illness in adolescents. In Canada, immunization against pertussis in public programs has been restricted to children under 7 years of age. The purpose of this analysis was to estimate the health and economic impact of an additional booster dose of the acellular vaccine in adolescents in Québec.

Effectiveness of serogroup C meningococcal polysaccharide vaccine: results from a case-control study in Quebec.

Background: After a mass-immunization campaign in the province of Quebec, Canada, from 1992 to 1993, a case-control study was conducted to evaluate the effectiveness of the polysaccharide vaccine, while controlling for the potential confounding effects of selected risk factors for serogroup C meningococcal disease.

Methods: The case patient group comprised 74 individuals with confirmed serogroup C meningococcal disease reported after the beginning of the campaign until 31 March 1998. Four control subjects, matched for age and place of residence, were randomly selected from the Quebec health insurance registry.

Comparative long term immunogenicity of two recombinant hepatitis B vaccines and the effect of a booster dose given after five years in a low endemicity country.

Background: Few data are available concerning the long term immunogenicity of the pediatric doses of hepatitis B vaccines given to preteenagers. The long term effect of the booster dose in teenagers is unknown. We evaluated the immunogenicity of 2 pediatric hepatitis vaccines after primary vaccination and after a booster dose.

[Coverage of anti-tetanus vaccinations in adults in Canada-year 2002. ].

Introduction: The rare cases of tetanus that have occurred in Canada were in adults whose vaccination was not up-to-date. The objective of this study was to estimate the vaccine coverage in Canadian adults.

Methods: 1,002 individuals 18 years of age and older selected by random digit dialing were interviewed by telephone in February 2002.

Effectiveness of a mass immunization campaign using serogroup C meningococcal conjugate vaccine.

Context: Meningococcal polysaccharide vaccines are of limited effectiveness. New protein-polysaccharide conjugate vaccines have yet to be evaluated in field conditions.

Objective: To assess the effectiveness of a serogroup C conjugate meningococcal vaccine in an outbreak setting.

Recurrence risk of oculorespiratory syndrome after influenza vaccination: randomized controlled trial of previously affected persons.

Background: Oculorespiratory syndrome (ORS) after influenza vaccination has many features of an allergic reaction.

Methods: The objective of the study was to estimate the recurrence rate of ORS after receipt of either of 2 influenza vaccines available in Canada for the 2002-2003 influenza season in individuals who experienced ORS in 2000 or 2001. We designed a randomized, crossover, double-blind, placebo-controlled trial in which patients received the vaccine and the placebo 7 days apart.

Measles elimination in Canada.

To describe the progress and challenges in achieving measles elimination in Canada, we analyzed national data on measles cases for 1998-2001. To assess the status of measles elimination in Canada, we estimated the effective reproductive number, R. Measles elimination was defined as the interruption of endemic transmission and failure to reestablish endemic transmission after importation.

Assessment of the status of measles elimination from reported outbreaks: United States, 1997-1999.

The status of measles elimination is best summarized by evaluation of the effective reproduction number R; maintaining R<1 is necessary and sufficient to achieve elimination. Previously described methods for estimating R from the sizes and durations of chains of measles transmission and the proportion of cases imported were applied to the measles data reported for the United States in 1997-1999. These comprised 338 cases, forming 165 chains of transmission, of which 43 had >1 case.

Multiplex real-time PCR assay for detection of influenza and human respiratory syncytial viruses.

A multiplex real-time PCR assay was developed with a LightCycler instrument for detection of influenza viruses A and B and the human respiratory syncytial virus (HRSV). Detection of each viral product and of an internal control was based on determination of specific melting temperatures by the LightCycler software. The lower limit of detection in the multiplex PCR assay was found to be 50 copies for each viral target.

Aggregate content influences the Th1/Th2 immune response to influenza vaccine: evidence from a mouse model.

During the 2000-2001 season, a newly identified oculo-respiratory syndrome (ORS) was detected across Canada as an adverse effect to one influenza vaccine. The implicated vaccine contained a higher than expected proportion of unsplit and aggregated influenza virions. Clinical and epidemiologic features of ORS were suggestive of type 2-like influences on the immune response.

[Public health: the control of meningococcal disease in Quebec].

A first outbreak of serogroup C meningococcal disease occurred in the province of Quebec in 1990-1992 and lead to a mass immunization campaign using polysaccharide vaccines. In 2001, a second outbreak was identified and a mass vaccination campaign was carried out, using the newly licensed conjugate vaccine. Clinical, epidemiological, economic and social studies were instrumental in the decision making for implementing these control programs.

Ophthalmological and biological features of the oculorespiratory syndrome after influenza vaccination.

We report the ophthalmological and laboratory findings of 6 patients who, after influenza vaccination, were affected by oculorespiratory syndrome (ORS), complaining of red eyes, photophobia, blurred vision, palpebral edema, ocular pain and itching, and conjunctival secretions. The conjunctivae were mildly hyperemic with few follicles, but the ophthalmological examination findings were otherwise normal. Patients had lymphopenia and decreased levels of the total hemolytic complement and the third and fourth component of the complement.

Randomized, double-blind, placebo-controlled trial to assess the rate of recurrence of oculorespiratory syndrome following influenza vaccination among persons previously affected.

During the 2000-2001 influenza immunization campaign in Canada, an oculorespiratory syndrome (ORS) was recognized as adverse event associated with one of the vaccines administered. The initial surveillance case definition for ORS in 2000-2001 specified onset within 24 h after vaccination and resolution within 48 h after onset; the restriction on the duration of ORS was removed from the case definition for the vaccine distributed during the 2001-2002 influenza season. The implicated vaccine contained large aggregates of unsplit virions; alterations to the manufacturing process for the vaccine distributed during 2001-2002 addressed this.

Varicella vaccine: factors influencing uptake.

Background: In Canada, varicella vaccine is recommended but its uptake has been low. In contrast to most other recommended paediatric vaccines, this one is not currently provided free of charge in all provinces and territories in Canada.

Objective: To evaluate the rate of health care provider offer of varicella vaccine to parents and the most important determinants of parental decision to accept the offer.

Strain variation among Bordetella pertussis isolates from Québec and Alberta provinces of Canada from 1985 to 1994.

Pulsed-field gel electrophoresis and gene typing were able to differentiate among 3,597 Bordetella pertussis isolates circulating in Alberta and Québec Provinces, Canada, from 1985 to 1994 and distinguish them from the strains used in vaccine production. This study provides a baseline for continued surveillance of prevalent and emerging strains of B. pertussis in Canada.

[Why are some children incompletely vaccinated at the age of 2?].

: A survey was conducted in the Province of Quebec to document the factors associated with an incomplete immunization status among 2-year-old children. : Parents of 430 completely and 266 partially vaccinated children selected from the computerized vaccination register agreed to participate. : The non-simultaneous administration of the 2nd MMR and 4th DPT-P-Hib at 18 months of age was responsible for 46% of incompleteness.

Human metapneumovirus infections in hospitalized children.

We evaluated the percentage of hospitalizations for acute respiratory tract infections in children < or =3 years of age attributable to human metapneumovirus (HMPV) and other respiratory viruses in a prospective study during winter and spring 2002. We used real-time polymerase chain assays and other conventional diagnostic methods to detect HMPV, human respiratory syncytial virus (HRSV), and influenza viruses in nasopharyngeal aspirates of children. HMPV was detected in 12 (6%) of the 208 children hospitalized for acute respiratory tract infections, HRSV in 118 (57%), and influenza A in 49 (24%).

The clinical spectrum of the oculo-respiratory syndrome after influenza vaccination.

Oculo-respiratory syndrome (ORS), a new influenza vaccine associated adverse event, was identified in 2000. The 2000 case definition (ORS-2000) required the presence of bilateral red eyes or respiratory symptoms or facial edema occurring between 2 and 24h following immunization and lasting View Article and Find Full Text PDF

Oculo-respiratory syndrome following influenza vaccination: evidence for occurrence with more than one influenza vaccine.

We assessed the occurrence of oculo-respiratory syndrome (ORS) following two influenza vaccines: Fluviral (Shire Biologics) or Vaxigrip (Aventis Pasteur). ORS was identified amongst 5.3 and 4.