How Should Risk Assessment Help To Guide The Decision Process On Veterinary Biologicals

Submitted By Ritu-Saini
Words: 4635
Pages: 19

Rev. sci. tech. Off int. Epiz., 1995, 14 (4), 913-923
Reproduced with permission from OIE.
Web reference for this OIE Publication: http://www.oie.int/eng/publicat/A_RT14.htm Limitations, definitions, principles and methods of risk analysis
D.W. NORTH

Summary: Decisions on veterinary biologicals involve large uncertainties, complexities which cut across many scientific and technical disciplines, and large potential adverse impacts on public health and on important sectors of the economy.
How should risk assessment help to guide the decision process on veterinary biologicals? How can risk assessment practices be harmonized internationally, given the different regulatory traditions and institutions of different countries?
A broad view of risk assessment is needed, that risk assessment is a framework for summarizing applicable scientific judgement in support of regulatory decision-making.
Support for this view of risk assessment is found in the major reports which have defined risk assessment as currently practised by many regulatory agencies in the
United States of America (USA). However, some interested and affected parties perceive risk assessment in the USA as overly quantitative and narrowly focused on regulatory standards for carcinogens. An example of risk assessment for microbial contamination indicates how quantitative methods can be used when data are sparse and decisions must be made in the face of great uncertainty. Such quantitative methods can be used to improve communication about risk, to promote consensus in support of controversial decisions, and to identify valuable opportunities for research to reduce the important sources of uncertainty.

KEYWORDS: Assessment of judgmental probabilities - Decision analysis - Planetary quarantine - Risk assessment - Risk management - Uncertainty - Viking Mission to
Mars.

INTRODUCTION
The papers presented at this Symposium and those contained in Volume 12 (4),
December 1993, of the Scientific and Technical Review of the Office International des
Epizooties (OIE) devoted to 'Risk analysis, animal health and trade', indicate that the community working to harmonize the regulation of veterinary biologicals has already acquired a sophisticated knowledge of risk assessment. Consequently, this introduction to the subject is brief, and definitions used for the main concepts are those already in the literature, in particular those given by S.C. MacDiarmid (7) in the above-mentioned issue of the
OIE Scientific and Technical Review. No attempt is made here to reconcile the definitions proposed by MacDiarmid with those of other authors in this issue, but rather they are taken as a point of departure.

* Decision Focus Incorporated. 650 Castro Street, Mountain View, California 94041-2055, United States of
America.

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`Risk, as it relates to the importation of animals or animal products, is a measure of the probability of the introduction of an exotic disease and the seriousness of such an outcome.
Risk analysis is a blend of art and science, and comprises risk identification, risk assessment, risk management and risk communication.'
Risk may be defined more broadly as the probability of occurrence of an adverse outcome and the severity of the consequences if the outcome does occur.
MacDiarmid (7) notes that risk analysis must begin with risk identification. The potential adverse outcomes must be listed at the outset of the risk analysis process, and it is a good idea to include the marginal entries on the list. If adverse outcomes (e.g. diseases caused by specific pathogens) do not appear on the list, then the risk analysis could omit aspects of great importance for regulatory decision-making. If some adverse outcomes have such low probabilities or mild consequences that they are clearly not important, then they can be dropped from the analysis. But initially it is better to be inclusive, to err on the side of caution, and to try to anticipate unpleasant surprises. Not all the possible