Transfusion Transmitted Injuries Surveillance System
Project Progress Report 2001-2002

Preface

The Transfusion Transmitted Injuries (TTI) Section of the Blood Safety Surveillance and Health Care Acquired Infections Division at Health Canada has been assigned to carry out activities to support the development of a National Transfusion Transmitted Injuries Surveillance System (ttiss). The objectives of the ttiss are:

• To capture data on moderate and severe adverse events of transfusion To capture data on serious errors/near misses of blood/blood transfusions
• To capture delayed adverse events of transfusion including transmission of infectious diseases due to transfusion of blood/blood products
• To perform risk assessment:
  • Data analysis and measuring the magnitude of risks
  • Monitor trends over time
  • Measure the risks in relation to epidemiological characteristics (person/time/place)
• To produce reports and disseminate information to support risk management activities and regulatory actions.

Given the advances in testing technology, the risk of acquiring a viral infectious disease through blood transfusion is now extremely low in Canada which has one of the safest blood supplies in the world. The viral risks for HIV, HCV and HBV are now estimated to be 1 in 10 million, 1 in 2,857,000 and 1 in 72,000 units of blood transfused respectively (Chiavetta et al, CMAJ 2003; 169:767-773).

However, bacterial contaminations and non-infectious hazards related to blood transfusion continue to occur at a much higher frequency. They can frequently go unrecognized and are often underreported. The non-infectious hazards can have multiple causes, some related to the transfusion practices at the hospital, others to the clinical condition of the recipients or because of some interactions between the biological product being transfused and the recipient's characteristics.

The ttiss is a voluntary surveillance system that has been implemented to improve transfusion reaction reporting, which can enable us to have a better knowledge of the frequency of transfusion reactions occurring in Canada and assist us in program planning to reduce transfusion risks. This system is in addition to and does not replace the current existing regulatory requirements in place at Health Canada for reporting of serious adverse events related to transfusion of blood products and components.

The present document is the first progress report on the current status of the surveillance system launched in 1999. It addresses adverse events reported to the ttiss for the period April 1, 2001 to June 30, 2002, by the provinces of British Columbia, Quebec, Nova Scotia and Prince Edward Island. The provinces of Ontario, New Brunswick, Alberta and Manitoba joined the surveillance system in April 2002. Data from these locations were either not available or not within the reporting period, due to the start-up time required to produce data. Their data will be included in subsequent reports.

The ttiss project has been a success and a great example of collaboration between health care professionals working together to build a surveillance system aimed at monitoring adverse transfusion reactions. It is important to remember that the results presented in this document are those of a project during its pilot stage. The project has since been expanded and is now a national system. Tremendous progress has been made to improve the system, based on the limitations found in the pilot project. Case definitions have been refined, signs, symptoms and laboratory results are provided in order to validate the cases, and a more in-depth investigation of the cases is now conducted. A Data Review group, with experts across Canada has been instituted to review the data twice a year, make recommendations for enhancing the system, and provide suggestions on any major issues identified. Moreover, denominator data on the number of units of blood transfused will be provided by the provinces/territories for the estimation of risks of the adverse events. This will allow for the comparison of our data to other international hemovigilance systems. An error surveillance system is being developed and methods to capture delayed infections related to transfusion are being addressed.

Implementation of the ttiss would not have been possible without the involvement of the pilot provinces representatives of British Columbia, Dr. David Pi; Québec, Dr. Pierre Robillard; Nova Scotia, Dr. David Anderson; Prince Edward Island, Dr. Linda Van Til as well as the Blood Manufacturers, Canadian Blood Services and HÉM A-QUÉBEC representatives, and the regulatory groups of Health Canada.

Specifically, I would like to express my gratitude to these representatives for the tremendous work accomplished in the development of the surveillance system, mainly in reaching agreement on the data elements to be collected and transferred to Health Canada, the standardized definitions to be used for the data elements and the standardized form for reporting the data elements.

I am indebted as well to the staff of the TTI Section, Blood Safety Surveillance and Health Care Acquired Infections Division, Nancy McCombie, Magalie Cator, Nick Karitsiotis and his team, Mary-Ann Wotherspoon and Marlène Huard, who worked diligently in the development of the surveillance system and in the preparation of this report.

The contribution of all participants and the continuous support of our collaborators are greatly appreciated. I look forward to the future involvement of the remaining provinces and territories for a comprehensive national surveillance system in the next year.

Antonio Giulivi, MD, FRCPC
Director
Blood Safety Surveillance and Health Care Acquired Infections Division
Centre for Infectious Disease Prevention and Control
Public Health Agency of Canada
Health Canada

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