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BACKGRoUND: When moderate or severe adverse events occur after vaccination, physicians and patients may have concerns about future immunizations. Similar concerns arise in patients with underlying conditions whose risk for adverse events may differ from the general population. The Special Immunization Clinic (SIC) network was established in 2013 at 13 sites in Canada to provide expertise in the clinical evaluation and vaccination of these patients. oBjECTIVES: To assess referral patterns for patients with vaccine adverse events or potential vaccine contraindications among paediatricians and to assess the anticipated utilization of an SIC. METHoDS: A 12-item questionnaire was distributed to paediatricians and subspecialists participating in the Canadian Paediatric Surveillance Program through monthly e-mail and mail contacts. RESULTS: The response rate was 24% (586 of 2490). Fifty-three percent of respondents practiced general paediatrics exclusively and 52% reported that they administer vaccines. In the previous 12 months, 26% of respondents had encountered children with challenging adverse events or potential vaccine contraindications in their practice and 29% had received referrals for such patients, including 27% of subspecialists. Overall, 69% of respondents indicated that they would be likely or very likely to refer patients to an SIC, and 34% indicated that they would have referred at least one patient to an SIC in the previous 12 months. CoNCLUSIoNS: Patients who experience challenging adverse events following immunization or potential vaccine contraindications are encountered by paediatricians and subspecialists in all practice settings. The SIC network will be able to respond to a clinical need and support paediatricians in managing these patients.

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. Consequently we do not know the incidence of infection in children and what would be the most appropriate age for hepatitis A vaccination. Objective: To estimate the proportion of 8- to 13-year-old children who have been infected with hepatitis A virus (HAV) and the risk factors for this infection on a nationwide scale. Methods: Children were sampled in 10 Canadian provinces, comprising 5 regions, using random digit dialing methodology with regional stratification. Demographic data and information about risk factors for hepatitis A were collected by the telephone interviewers. Oral fluid samples were self-collected and mailed to the laboratory, where they were tested for anti-HAV IgG. Results: Of 6740 contacted families with a child of required age, 1688 (25%) agreed to participate and answered the questionnaire. From these, 1074 oral fluid samples were received, and 1057 could be analyzed. Anti-HAV IgG was detected in 2.7% of subjects, with variation by region from 0.8 to 3.4%. The parents of 54 subjects (5.1%) reported that their child had previously been vaccinated against HAV. Anti-HAV IgG was present in 2.0% of unvaccinated subjects, among whom antibody prevalence was 19.4% in children born in HAV-endemic countries, 6.1% in Native children and 4.2% in travelers to endemic countries. In multivariate analysis of all subjects, the presence of anti-HAV IgG was significantly associated with birth in an endemic country, travel to an endemic country, Native status (American Indian and Inuit population), female gender and vaccination against HAV. In nonvaccinated, non-Native children born in Canada who did not travel to endemic countries, anti-HAV prevalence was 1.1%. Conclusions: The risk for hepatitis A during childhood is low in Canada. Almost all teenagers (>97%) would be at risk for infection in case of contact with HAV. Changes in immunization policy against hepatitis A should be considered.

OBJECTIVE A survey was conducted in the Province of Quebec to document the factors associated with an incomplete immunization status among 2-year-old children. METHODS Parents of 430 completely and 266 partially vaccinated children selected from the computerized vaccination register agreed to participate. RESULTS The non-simultaneous administration of the 2nd MMR and 4th DPT-P-Hib at 18 months of age was responsible for 46% of incompleteness. The following characteristics were significantly associated with an incomplete immunization status: being a single parent, > or = 2 children in the family, an older age at first immunization (> or = 3 months), parent's preference for postponing the second vaccine when two injections are scheduled for the same visit, perception of lack of information about vaccination, and disagreement with immunization recommendations. CONCLUSION One of the key points of this study is the impact of the non-simultaneous administration of the two vaccines at 18 months. Factors such as being a single parent and older age at first immunization might be used to design an early intervention for children who are most likely to be incompletely immunized. Even if parents are favourable towards immunization, they need to be well informed about the associated risks and benefits.

UNLABELLED We estimated the accuracy of the information in the vaccination booklet of 8,457 children. The booklets were classified as complete (CC), incomplete (CI) or lost (CP). For children in the CI or CP categories, an active search was done in their providers' records and we assessed their vaccine coverage. Overall, the booklet provided accurate information for 88.6% of the 7,646 children who were vaccinated at least once. Among the 711 children in the CI category, the active search showed that 79% had received all their vaccines at age two years whereas this proportion was 59% among the 280 children in the CP category. The active search increased the vaccine coverage in the population by 4%. CONCLUSION The majority of children in the CI or CP categories whose parents report that they received all their vaccines are in fact adequately vaccinated.

A questionnaire was mailed to all vaccinators in Quebec in 1998. The objective of this survey was to document vaccinators' attitudes, knowledge, and practices related to vaccination. Vaccinators generally believe in the security, efficacy and usefulness of vaccines given to young children. However, 41% of nurses do not fully agree with these opinions. More than 94% of pediatricians completely disagree that "certain practices (homeopathy, good eating habits and a healthy lifestyle) can eliminate the need for vaccination", compared with 85% of general practitioners and only 60% of nurses. Less than 25% of doctors recall children who are late in getting their immunizations; approximately 45% of vaccinators are in complete agreement with simultaneous injections of two vaccines; many circumstances are incorrectly seen as contra indications for vaccination. Public health authorities should target systematic interventions towards vaccinators to improve this situation and to increase nurses' conviction regarding the benefits of vaccination.