The Krever Commission — 10 years later

Precautionary measures

Perhaps the most significant contribution of the Krever report to public health was its clarification of how evidence should be used to formulate policy with respect to blood safety. Before the report was released, a prominent criticism of decision-making in this regard was the reliance on high-level evidence as a pre-requisite for action to protect the public's health. Although it was highly effective in guiding clinical decision-making, Justice Krever identified this approach as clearly inappropriate for blood safety. In particular, Krever criticized the delays in implementing measures to protect the blood supply from HIV because of uncertainty about the magnitude of this threat and delaying the implementation of surrogate testing for hepatitis C until clear evidence of its efficacy was available from a randomized trial.3^,6 Waiting for definitive evidence of risk resulted in the potentially avoidable exposure of thousands of individuals to tainted blood products. Krever stated that this approach was inconsistent with the public health ethos:

The slowness in taking appropriate measures to prevent the contamination of the blood supply was in large measure the result of the rejection, or at least the non-acceptance, of an important tenet in the philosophy of public health: action to reduce risk should not await scientific certainty. When there was reasonable evidence that serious infectious diseases could be transmitted by blood, the principal actors in the blood supply system in Canada refrained from taking essential preventive measures until causation had been proved with scientific certainty. The result was a national public health disaster.7

The reformed blood system has effectively incorporated Justice Krever's precautionary approach in addressing a series of potential infectious threats. At the time of its creation, the new blood system was immediately confronted with the first of these threats: the theoretical risk of transmission of variant Creutzfeldt–Jakob disease. Despite the lack of clear evidence of transmission of the disease through blood transfusion, measures to protect the public against this risk were instituted, including deferring donations from individuals who had travelled to the United Kingdom during the peak of the “mad cow” outbreak. In retrospect the decision appears to be prescient. The transmission of variant Creutzfeldt–Jakob disease by blood transfusion has been confirmed and found to be an efficient mechanism for spreading the infection.8^,9 The blood system responded in a similar way to the documentation of transmission of West Nile virus, first with recalls of potentially affected blood products and then with the introduction of a screening test for donors.10^,11 During the severe acute respiratory syndrome (SARS) crisis, the blood system introduced precautionary measures in its screening process, such as deferring donations from individuals at risk of harbouring the virus, without waiting for evidence of transfusion transmission.12 Table 1shows examples of infectious threats to the blood system and some of the policy responses, both before and after the system was reformed.

Although the precautionary approach had been an important concept in environmental policy, Justice Krever's report was highly influential in advocating for its application to public health. The concept has subsequently been widely adopted within public health and government risk-management practices. During the SARS outbreak, public health officials repeatedly called for precautionary measures to be adopted despite incomplete scientific information on the risk posed by the virus. In fact, Justice Archie Campbell's last report on the SARS outbreak in Ontario directly referred to Justice Krever's report when identifying the importance of incorporating precautionary decision-making to protect health worker safety.17 In addition, Canada's pandemic influenza planning process has been characterized by the need to take measures to protect against what is still a theoretical risk. In 2003, the federal government released a document describing how the precautionary approach should be used to guide all science-based risk decision-making.18

Governance

A second major contribution of the Krever Commission was its identification of the vital role of governance in ensuring safety in public health.13 The Krever report concluded that the structure of the previous blood system was flawed in at least 2 respects. First, the system was organized in a manner that allowed cost-considerations to affect decisions related to safety. Second, ambiguity over the roles and responsibilities of the various actors in the system created risks in the safety of blood products. The Krever report stated

In its report the safety audit committee concluded that responsibility for the blood system is fragmented … the various functions integral to the supply of blood, such as regulation, funding and planning, are undertaken by different stakeholders. The respective functions, authority and accountability of each party are not well defined. … This lack of definition may affect accountability within the system, and ultimately its safety.19

The new blood system was designed with these concerns in mind. Roles were clearly allocated to the new blood system actors. Canadian Blood Services was created as an arms-length organization — a not-for-profit Crown corporation that must respond to federal regulations but that also has the authority to exceed them. The provinces' primary role was to fund Canadian Blood Services; however, the organization does not have to seek decision-by-decision funding approval from the provinces. By insulating the operator from financial consideration in this way, the reformed blood system has flexibility in the introduction of aggressive safety measures that might otherwise have encountered opposition from a funding organization concerned about the absence of clear evidence for their efficacy.20