Recent years have seen an increase in the number of new vaccines available on the Canadian market, and increasing divergence in provincial and territorial immunization programs as jurisdictions must choose among available health interventions with limited funding. We present an analytical framework, which we have developed to assist in the analysis and comparison of potential immunization programs. The framework includes 58 criteria classified into 13 categories, including the burden of disease, vaccine characteristics and immunization strategy, cost-effectiveness, acceptability, feasibility, and evaluability of program, research questions, equity, ethical, legal and political considerations. To date this framework has been utilized in a variety of different contexts, such as to structure expert presentations and reports and to examine the degree of consensus and divergence among experts, and to establish priorities. It can be transformed for a variety of other uses such as educating health professionals and the general public about immunization.
To study complications and sequelae of serogroup B and C meningococcal disease, a retrospective survey examined the outcome of all culture-proven cases reported in the province of Quebec, Canada, from January 1990 through December 1994 (serogroup B, 167 cases; serogroup C, 304 cases). Data were collected from medical files, postal questionnaires, and telephone interviews. Age groups having the most cases were the 10-19-year age group for serogroup C and the
To evaluate the cost-effectiveness of a lottery on physicians' responses to a mail survey, a randomized controlled trial was conducted with a random sample of 1,000 members of the Quebec Federation of General Practitioners in 1997. For the first mailing of this survey, each respondent was randomly assigned to the control or experimental group, which was offered participation in a lottery upon return of the questionnaire. Response rate was 41.2% in the experimental group and 34.8% in the control group, a 6.4% difference (CI95%: 0.6%-12.6%). The additional cost of the lottery was about Can$500, giving an incremental cost of Can$16 per questionnaire returned. In conclusion, a lottery resulted in a small but statistically significant increase in the response rate of physicians to a mail survey. This method may be a cost-effective option when applied to large surveys.
The aim of this study was to evaluate the prevalence of congenital anomalies in 19 areas from 13 European countries. A total of 291,126 births were surveyed. On average most of the anomalies were recorded in livebirths. The total prevalence of congenital anomalies was 21.8 per 10,000 births. Four groups of congenital anomalies were of particular note in the consideration of geographic variations: neural tube defects, cleft lip, limb reduction defect and Down syndrome. For neural tube defects, 24 cases per 10,000 were recorded in the British Isles whereas only 9.6 cases per 10,000 were registered in Continental Europe. Cleft lip had a much higher prevalence in Groningen (The Netherlands) and in Odense (Denmark) than in the other European countries under study. The prevalence of limb reduction defect was high in Bilbao (Spain), in Odense, in Strasbourg (France) and in Groningen. In the study population the prevalence of Down syndrome ranged from 5.6 to 21.3 per 10,000 livebirths.
An outbreak of meningococcal disease in Quebec province prompted a mass immunization program. The impact of this campaign on the epidemiology of meningococcal disease has not been studied.
To study the impact of a mass immunization campaign using polysaccharide vaccine on the epidemiology of meningococcal disease (MCD) and to assess serogroup C vaccine effectiveness (VE).
Analysis of MCD cases reported in Quebec from 1990 to 1998, before and after the mass immunization campaign was conducted during the winter of 1992-1993, when 84% of residents aged 6 months to 20 years (the target population, approximately 1.9 million individuals) were vaccinated.
Incidence of MCD in 1990-1998; incidence of culture-proven serogroup C MCD between April 1, 1993, and March 31, 1998, compared among vaccinated and unvaccinated persons in the target population.
The incidence of serogroup C disease decreased after the mass immunization campaign, from 1.4 per 100 000 in 1990-1992 to 0.3 per 100 000 in 1993-1998, and the overall incidence of other serogroups remained stable at 0.7 per 100 000, with a small increase in the proportion of cases caused by serogroup Y (P =.009). Protection from serogroup C MCD was indicated in the first 2 years after vaccine administration (VE, 65%; 95% confidence interval [CI], 20%-84%), but not in the next 3 years (VE, 0%; 95% CI, -5% to 65%). Vaccine effectiveness was strongly related to age at vaccination: 83% (95% CI, 39%-96%) for ages 15 through 20 years, 75% (95% CI, - 17% to 93%) for ages 10 through 14 years, and 41% (95% CI, -106% to 79%) for ages 2 through 9 years. There was no evidence of protection in children younger than 2 years; all 8 MCD cases in this age group occurred in vaccinees.
Serogroup C polysaccharide vaccine is effective for controlling outbreaks in teenaged individuals but should not be used in children younger than 2 years. The mass campaign did not induce significant serogroup switching.
Comment In: JAMA. 2001 Mar 28;285(12):1578-911268264
A mass immunization campaign was conducted in the Province of Quebec, Canada, during the winter of 1993, following an increase in the incidence of meningococcal disease, which was mainly caused by a virulent clone of Neisseria meningitidis, serogroup C, serotype 2a. About 1.6 million doses of the polysaccharide vaccine were administered, covering 84% of the target population aged between 6 months and 20 years; the overall cost was about 25.5 million Canadian dollars. Cases notified to the regional health authorities by clinicians, hospital laboratories, and the provincial reference laboratory from January 1990 up to March 1994 have been included in the analysis. In the first year following the campaign, the incidence of the disease dropped markedly among vaccinees as well as the unvaccinated fraction of the target population, while it remained unchanged among persons aged more than 20 years. This suggests the existence of herd immunity. The overall field efficacy of the vaccine was 79%, more in teenagers and less in under-5-year-olds. A minimum of 37 cases were prevented during the first year.
Cites: J Exp Med. 1969 Jun 1;129(6):1385-954977284
Cites: Am J Epidemiol. 1970 Jul;92(1):25-324987716
Cites: Bull World Health Organ. 1971;45(3):279-825316907