The Canadian Paediatric Surveillance Program: A new opportunity to help shape public health policy

Initiated in January 1996, the Canadian Paediatric Surveillance Program (CPSP) is a collaborative program of the Canadian Paediatric Society, and the Centre for Infectious Disease Prevention and Control, Health Canada (1). The impetus behind the formation of the CPSP arose from the need for timely Canadian data on rare childhood conditions. Modelled after its successful British counterpart, the CPSP canvasses over 2350 Canadian paediatricians on a monthly basis, serving as a clearinghouse for projects, effectively channelling data, and co-ordinating researchers and respondents. As a result, participants feel a significant degree of ownership of the CPSP and are true stakeholders in the system. Respondents have contributed over 300 study-months of data collection and detected 300 cases of rare conditions, resulting in numerous presentations and publications in peer-reviewed journals.

CPSP objectives are to initiate projects of national importance, acquire sound funding and develop a strong infrastructure, including a steering committee, that represents the needs and views of both the paediatric and public health communities. Because the CPSP has great potential to make significant contributions to public and medical health, the program should be firmly established as a critical component of health surveillance in this country.

SCREENING

One critical feature of the CPSP is its ability to collect information on both the incidence and prevalence of rare conditions. This information is essential to establishing the need for screening for a specific condition and the circumstances under which this should be done. For Smith-Lemli-Opitz syndrome, a condition currently under study, early intervention can be associated with favourable long term outcomes. The findings of this study have the potential to influence policies on the screening for metabolic diseases and illustrate the potential utility of the CPSP in this area of public health.

PROGRAM EVALUATION

An essential role fulfilled by the CPSP has been to evaluate the success of public health interventions by directly tracking the effectiveness of a number of immunization programs. At a time when immunizations are being actively scrutinized as to their need and safety, the CPSP has been used by Health Canada to collect information on rare vaccine-preventable infections or their sequellae. For example, the congenital rubella program has confirmed the overall value of this initiative by monitoring the effectiveness of rubella vaccination in the general population. It also has contributed to the identification of the need for additional efforts to evaluate the effectiveness of vaccination for at-risk subpopulations, including Aboriginal and immigrant families. Through targeted and evaluated efforts, these groups may achieve the same level of protection that is enjoyed by the general population.

The CPSP provides supporting evidence for the stance taken by physicians and other health care professionals in promoting measles vaccination. The study on subacute sclerosing panencephalitits clearly demonstrates that this rare condition results as a complication of wild measles infection and not the virus strain in the vaccine. As well, the CPSP can play a pivotal role in determining whether a disease has been truly eliminated from our nation. Whether Canada can claim polio-free status will be determined, in part, through the CPSP’s ongoing study of acute flaccid paralysis. Through the studies mentioned above, the CPSP contributes to the assessment of the status of childhood diseases and does so in concert with other vital surveillance systems such as the Immunization Monitoring Program, ACTive.

PUBLIC POLICY

The CPSP has an opportunity to influence the development of ‘healthy public’ policy. Historically, the British Paediatric Surveillance Unit played a key role in examining the association between Reye syndrome and the consumption of acetylsalicylic acid (2). While one of the CPSP’s first studies (on neural tube defects) was not as conclusive as had been hoped, it provided valuable insights into how to assess an important public health intervention such as the addition of folic acid to common foodstuffs. The more recent CPSP study of hemorrhagic disease of the newborn reaffirmed the appropriateness of the current hospital practice of intramuscular vitamin K administration at birth. However, should there be a significant departure from or resistance to intramuscular vitamin K at the time of delivery, the CPSP is uniquely situated to compare future trends of disease prevalence with current ones. This type of monitoring is essential not only to the evaluation of the introduction of new products, but also to public rejection of established practices. Furthermore, other national paediatric surveillance programs have been used to determine whether community interventions, such as folic acid supplementation, are associated with increased risks or improved benefits (3).

The CPSP has the potential to serve as a basis for identifying populations that are at risk, and for obtaining important ecological and epidemiological data on their circumstances. The anaphylaxis study is currently identifying critical factors not only in treatment, but also in community circumstances surrounding this potentially life-threatening condition. At the conclusion of this study, health policies in locales such as schools and daycares may need to be reviewed and modified in areas ranging from timely intervention with self-administering medication devices to restrictions on nut-bearing foods.

EMERGING DISEASES

The CPSP has the potential to serve as an important beacon in the event of significant threats to the health of the public. The program is currently collaborating in the international surveillance of new variant-Creutzfeldt-Jakob disease, the human disease linked to the consumption of meat products from cattle that are infected with bovine spongiform encephalopathy or ‘mad cow’ disease. With the reporting of bovine spongiform encephalopathy-infected cattle in several European countries and cases of variant-Creutzfeldt-Jakob disease occurring in increasing numbers in the United Kingdom and in two other European countries, a study of progressive intellectual and neurological deterioration will provide valuable insights into the epidemiology of this fatal condition, as well as contribute to the surveillance for the disease in Canada. This study highlights the benefit of shared mutual experiences of other national paediatric surveillance systems of rare events and conditions. Further recognition of the importance of international collaboration and the investigation of rare events was given at the meeting of the International Network of Paediatric Surveillance Units, hosted by the CPSP in Ottawa, Ontario in June 2000.

International collaborations on specific conditions can result in an acceleration of the acquisition of timely information for public health decisions. These networks of surveillance are not only proving to be useful to public health practitioners in their respective countries, but are also providing a perspective that can best be described as one of enhanced ‘global village’ surveillance.

CONCLUSION

The CPSP is increasingly recognized as a key element in the surveillance of rare and unusual childhood diseases; a reporting base of over 2300 regularly contributing paediatricians and subspecialists makes it the largest paediatric surveillance program of its kind in the world. Health Canada has provided core funding for the program for the next four years. However, the success of the CPSP in the number of studies undertaken will pose greater administrative demands and present ongoing financial challenges. Future responsibilities include: the maintenance of a high response rate; availability of external funding sources for researchers of rare conditions; expansion of the reporting base to include other specialties related to the treatment of children; and facing new issues such as increased concern and restrictions on data arising from new privacy legislation. Nevertheless, the program is rapidly establishing itself as one of the pillars of national surveillance, supporting both health care and public health communities.