Key questions for proponents of child health are: What is the current immunization rate of young children in Canada and how does it compare with rates in other affluent countries?
A recent report from UNICEF (1) attempted to provide answers to these important questions using the early childhood immunization rate as “an indicator of the availability and effectiveness of a country’s basic preventive health services”. Canada fared poorly in comparison with other affluent countries, ranking 28th among 29 countries. The immunization coverage rate cited for Canada was 84%, compared with rates of 96% in the United Kingdom, and 93% in the United States and Australia. Canada was one of only three countries with rates <90%. The coverage rate was based on the percentage of 12- to 23-month-old children who had received at least one dose of measles-containing vaccine and three doses of diphtheria, pertussus and tetanus/polio vaccines. This metric is easier to meet than the conventional metric, which considers all vaccines and doses recommended to 18 months and measures uptake at two years of age (2), the application of which would have reduced the coverage estimate for Canada even further.
The UNICEF report did not specify the source or time frame of the Canadian data. The most recently available national data on childhood immunization (if used) were published in 2006, based on a nationwide telephone survey in 2004 that involved a weighted sample of 499 infants 20 to 40 months of age, assessed for vaccine uptake by the second birthday (3). Whether 10-year-old data from a small sample approximate current coverage rates is uncertain. Statistics Canada conducts biennial sample surveys of national immunization rates, most recently in 2011 and 2013; however, results have not been released to the public. It has not been possible to compile a national perspective using panprovincial data because not all provinces regularly measure coverage rates, and those that do use different methods and metrics. However, our examination of available coverage data from several provinces supports the UNICEF report that Canadian rates are <90%, substantially so for some vaccines recommended for young children. For example, in Manitoba, with a good provincial immunization registry, the proportion of two-year-olds who were up to date for all recommended immunizations was 61% in 2011 (4). Series completion was lowest for pneumococcal conjugate vaccine (68%). In British Columbia that same year, the proportion of two-year-olds who had received one dose of measles, mumps and rubella vaccine was 75%.
The UNICEF report demands the attention of providers of preventive health services in Canada. Why are we at the bottom of the ranking list? An important difference is that top-rated countries invest in and disseminate their annual coverage rates. Without access to regularly measured, valid coverage rates, a key stimulus to improvement is lost. While national coverage data are relevant for international comparisons, in the Canadian context, provincial data, with regional and district details, provide the basis for remedial action and should be regularly determined in every province. The pending availability of electronic immunization registries in more provinces will facilitate tracking of individual children through the series of recommended immunizations, provide opportunities to prompt those who fall behind and greatly simplify the generation of coverage reports. Other desirable registry capabilities include capturing all vaccines given by all providers, accessibility by parents and providers for individual records, and portability of personal records among provinces. Implementing suitable (and, ideally, similar) registry technologies should be a high priority in every province. The current implementation of the long-awaited Panorama registry platform in several provinces may be an important step forward. A novel electronic ‘app’ that could also help parents to improve compliance with the childhood immunization schedule is currently being tested in Ontario, with plans to expand use to the rest of the country.
The highest-ranked countries in the UNICEF report also benefit from having a uniform national immunization program, which enhances communication about the program and facilitates program evaluation, results of which bolster public and provider confidence. The diversity of programs within Canada affords none of these advantages and poses ongoing challenges. Canada will not be able to join the top-ranked countries until the provinces and territories voluntarily agree to provide uniform immunization programs, creating a national program by consensus. Such a development offers many advantages to the participating provinces and would provide the federal government with appropriate leadership and support opportunities. For example, the National Immunization Strategy implemented in 2003 provided federal start-up funding that enabled all provinces and territories to implement new programs with varicella, pneumococcal conjugate and meningococcal conjugate vaccines and, later, with human papillomavirus vaccine. This innovative measure effectively standardized immunization program content across the nation; however, it is uncertain whether such federal leadership will be continued if/when the National Immunization Strategy is renewed. The opportunity for the federal government to assist the provinces in creating a national immunization program by consensus should not be missed.
A companion to the UNICEF report written by UNICEF Canada was titled ‘Stuck in the Middle’ (5). With respect to childhood immunization, it could have said ‘stuck at the bottom’ among similar rich nations. Consequently, coverage rates here are more vulnerable to negative influences such as the growing reluctance of parents to immunize their children as recommended. Top-rated countries support their immunization programs in additional ways, some of which may be helpful in Canada. In the United States, a national recommendation to use a new vaccine automatically triggers a number of federal, state and private-sector funding mechanisms, ensuring universal access to the vaccine. School entry requirements in nearly all states demonstrate a commitment to the value of childhood immunization and encourage compliance. In Australia, the state signals its commitment to childhood immunization by linking child benefit payments to evidence of schedule compliance unless a medical exemption exists. In contrast, the low-key promotion of childhood immunization in Canada fails to convey a deep societal commitment to its extraordinary value.
The UNICEF report must be taken seriously: improvements are urgently needed in immunization services and coverage rates. It is not about improving the national ranking per se but bettering infection prevention measures among children at risk. We can and should do better, with the key steps being: achievement of a uniform national immunization program; establishment of a suitable electronic immunization registry in every province and territory; and utilization of registries and other methods to closely monitor and publicize coverage rates, leading to remedial action where rates are low. Other strategies to encourage timely immunization that have been successful in top-rated countries should also be considered.