食品致病菌風險評估
黃顯宗
• 微生物有很多是人類重要的病原菌，影響
人類健康
• 微生物風險評估含：Risk Assessment,
Risk Management, and Risk
Communication
• Overall objective to ensure public health
protection
落實？
• Since Microbiological Risk Assessment
is a developing science, implementation
of these guidelines may require a period
of time and may also require specialized
training in the countries that consider it
necessary.
References
Anonymous. 1999. Principles and guidelines for the conduct of
microbiological risk assessment. CAC/GL-30 - 1999
Anonymous. 2011. Risk assessment of Vibrio parahaemolyticus in seafood.
World Health Organization/Food and Agriculture Organization of the United
Nations.
Anonymous. 2000. Draft risk assessment on the public health impact of
Vibrio parahaemolyticus in raw molluscan shellfish. Food and Drug
Administration, USA.
Iwahori J, Yamamoto A, Suzuki H, Yamamoto T, Tsutsui T, Motoyama K,
Sawada M, Matsushita T, Hasegawa A, Osaka K, Toyofuku H, Kasuga F.
2010. Quantitative risk assessment of Vibrio parahaemolyticus in finfish: a
model of raw horse mackerel consumption in Japan. Risk Anal. 30:18171832.
名詞定義
• Dose-Response Assessment劑量反應評估 - The
determination of the relationship between the
magnitude of exposure (dose) to a chemical, biological
or physical agent and the severity and/or frequency of
associated adverse health effects (response).
• Exposure Assessment暴露評估 - The qualitative
and/or quantitative evaluation of the likely intake of
biological, chemical, and physical agents via food as
well as exposures from other sources if relevant.
名詞定義
• Hazard危害 - A biological, chemical or physical agent
in, or condition of, food with the potential to cause an
adverse health effect.
• Hazard Characterization危害特徵描述 - The qualitative
and/or quantitative evaluation of the nature of the
adverse health effects associated with the hazard. For
the purpose of Microbiological Risk Assessment the
concerns relate to microorganisms and/or their toxins.
名詞定義
• Hazard Identification危害鑑定 - The identification of
biological, chemical, and physical agents capable of
causing adverse health effects and which may be
present in a particular food or group of foods.
• Quantitative Risk Assessment量化風險評估 - A Risk
Assessment that provides numerical expressions of
risk and indication of the attendant uncertainties
(stated in the 1995 Expert Consultation definition on
Risk Analysis).
名詞定義
• Qualitative Risk Assessment 質化風險評估- A Risk
Assessment based on data which, while forming an
inadequate basis for numerical risk estimations,
nonetheless, when conditioned by prior expert
knowledge and identification of attendant uncertainties
permits risk ranking or separation into descriptive
categories of risk.
• Risk風險 - A function of the probability of an adverse
health effect and the severity of that effect,
consequential to a hazard(s) in food.
名詞定義
• Risk Analysis風險分析 - A process consisting of three
components: risk assessment, risk management and
risk communication.
• Risk Assessment風險評估 - A scientifically based
process consisting of the following steps: (i) hazard
identification, (ii) hazard characterization, (iii) exposure
assessment, and (iv) risk characterization.
名詞定義
• Risk Characterization風險特徵描述 - The process of
determining the qualitative and/or quantitative
estimation, including attendant uncertainties, of the
probability of occurrence and severity of known or
potential adverse health effects in a given population
based on hazard identification, hazard characterization
and exposure assessment.
• Risk Communication風險溝通 - The interactive
exchange of information and opinions concerning risk
and risk management among risk assessors, risk
managers, consumers and other interested parties.
名詞定義
• Risk Estimate 風險特徵描述結果- Output of Risk
Characterization.
• Risk Management風險管理 - The process of weighing
policy alternatives in the light of the results of risk
assessment and, if required, selecting and
implementing appropriate control2 options, including
regulatory measures.
• Sensitivity analysis敏感性分析 - A method used to
examine the behaviour of a model by measuring the
variation in its outputs resulting from changes to its
inputs.
名詞定義
• Transparent透明度 - Characteristics of a process
where the rationale, the logic of development,
constraints, assumptions, value judgements, decisions,
limitations and uncertainties of the expressed
determination are fully and systematically stated,
documented, and accessible for review.
• Uncertainty analysis 不確定性分析- A method used to
estimate the uncertainty associated with model inputs,
assumptions and structure/form.
微生物風險評估準則
• 1. Microbiological Risk Assessment should be soundly
based upon science.
• 2. There should be a functional separation between
Risk Assessment and Risk Management.
• 3. Microbiological Risk Assessment should be
conducted according to a structured approach that
includes Hazard Identification, Hazard
Characterization, Exposure Assessment, and Risk
Characterization.
• 4. A Microbiological Risk Assessment should clearly
state the purpose of the exercise, including the form of
Risk Estimate that will be the output.
微生物風險評估準則
• 5. The conduct of a Microbiological Risk Assessment
should be transparent.
• 6. Any constraints that impact on the Risk Assessment
such as cost, resources or time, should be identified
and their possible consequences described.
• 7. The Risk Estimate should contain a description of
uncertainty and where the uncertainty arose during the
Risk Assessment process.
• 8. Data should be such that uncertainty in the Risk
Estimate can be determined; data and data collection
systems should, as far as possible, be of sufficient
quality and precision that uncertainty in the Risk
Estimate is minimized.
微生物風險評估準則
• 9. A Microbiological Risk Assessment should explicitly
consider the dynamics of microbiological growth,
survival, and death in foods and the complexity of the
interaction (including sequelae) between human and
agent following consumption as well as the potential
for further spread.
• 10. Wherever possible, Risk Estimates should be
reassessed over time by comparison with independent
human illness data.
• 11. A Microbiological Risk Assessment may need
reevaluation, as new relevant information becomes
available.
腸炎弧菌風險評估
風險分析與管理
腸炎弧菌風險評估
• Anonymous. 2011. Risk assessment of Vibrio
parahaemolyticus in seafood. WHO/FAO of
the United Nations.
• Anonymous. 2000. Draft risk assessment on
the public health impact of Vibrio
parahaemolyticus in raw molluscan shellfish.
FDA, USA.
日本
• Wahori J, Yamamoto A, Suzuki H, Yamamoto T, Tsutsui T,
Motoyama K, Sawada M, Matsushita T, Hasegawa A, Osaka K,
Toyofuku H, Kasuga F. 2010. Quantitative risk assessment of
Vibrio parahaemolyticus in finfish: a model of raw horse mackerel
consumption in Japan. Risk Anal. 30:1817-1832.
• Hara-Kudo Y, Saito S, Ohtsuka K, Yamasaki S, Yahiro S, Nishio
T, Iwade Y, Otomo Y, Konuma H, Tanaka H, Nakagawa H,
Sugiyama K, Sugita-Konishi Y, Kumagai S. 2012. Characteristics
of a sharp decrease in Vibrio parahaemolyticus infections and
seafood contamination in Japan. Int.J.Food Microbiol. 157:95-101.
降低原因
• 10oC以下冷藏保存
• 使用衛生的海水或清水處理
• 設定腸炎弧菌的限量（25g熟鱆魚螃蟹零
檢出，生食海產低於100 MPN/g等）
• 海產離冷藏後兩小時內食用
• 2001年後四分一的廚房換了新冰箱，半數
廚房使用時直接從冷藏取海產
• 半數以上海產賣場與餐廳檢驗員工糞便中
腸炎弧菌
聯合國報告
• To estimate risk of illness from VP due to consumption
of oysters in Australia, Canada, Japan and New
Zealand
• The Bloody clam risk assessment：A case study of
performing a quantitative risk assessment in a
developing country using local data. It focused on one
city in Thailand
• The purpose of the finfish risk assessment was to
estimate the risk of V. parahaemolyticus infection from
raw horse mackerel consumption in Japan, and to
estimate the risk reduction from washing this fish after
harvest or during preparation.
風險評估限制Constraints
• 大部分缺乏在地數據，只得引用美國數據
Hazard identification
• 致病情形
• 病人與案件
• 病人與案件數
Exposure assessment for raw oysters
• Four factors were used to model
exposure:
– level of pathogenic VP in seafood at harvest
– effect of post-harvest handling and
processing
– ability of the organism to multiply to an
infective dose
– number of pathogenic VP consumed
Harvest Module of the V.
parahaemolyticus
Exposure assessment for raw oysters
• Factors considered as influencing the numbers
of pathogenic V. parahaemolyticus at
consumption include:
– ambient air temperatures at time of harvest
– time from harvest until oysters are placed
under refrigeration
– time it takes for oysters to cool once under
refrigeration
– length of refrigeration time until consumption
Post-harvest
Module of the V. parahaemolyticus
Exposure assessment for horse
mackerel
Hazard characterization
Risk characterization
• 牡蠣，基於各地生產與溫度狀況，預測年
度病例：
Risk characterization
• Horse mackerel
• The risk assessment model estimated that the
probability of becoming ill per serving of raw horse
mackerel was 8.77 × 10-7 (best scenario) to 3.75 × 10-5
(worst scenario).
• For the Japanese population, the estimate was 70–
1300 cases per year.
• Epidemiological data indicates around 10 000 cases
annually, but the implicated seafoods are not always
identified.
Risk characterization
• Horse mackerel
• 各情境下病例預測
Impact of establishing limits for the
level of V. parahaemolyticus
in oysters
風險評估
• Harvest Module
• Post-harvest Module
– 收穫後至食用時的處理
• Public Health Module
– 國人食用生海產頻率
美國牡蠣VP風險評估模式
有關牡蠣，尚有許多研究工作需要進行
• 1、環境影響因子，如溫度、鹽度、獵食者、動
物passage、外地來菌種等，影響腸炎弧菌在所
有的區域與季節的分佈與茲長。
• 2、換水速率，如淡水、潮汐、養殖深淺、風等。
• 3、收穫時致病性腸炎弧菌的分佈與菌數。
• 4、在不同溫度的水產中致病性腸炎弧菌的茲長
與存活。
有關牡蠣，尚有許多研究工作需要進行
• 5、工業上收穫後處理的情形，如：至冷藏的時間、冷
藏速率與時間、冷藏的長短等。收穫後處理的程序對於
腸炎弧菌茲長的影響，這裡包含在海水箱中淨化
（depuration），或在乾淨的養殖環境中重新安置
（relaying）等程序。
• 6、人們攝食的模式，季節與區域的生吃頻繁程度、危
險（易感染）人口的攝食情形。
• 7、從集體中毒事件、流行病學、動物與其他研究中得
到菌量與致病的關係（dose-response relations），這
裡指不同的菌株、不同感受性（susceptibility）的消費
者。
有關牡蠣，尚有許多研究工作需要進行
• 8、TDH外可能的病原因子，如TRH、urease、腸毒素、
酸適應、腸道入侵等。
• 9、不同菌株的致病性監測assay。
• 10、海產生物的生理與免疫狀態與腸炎弧菌數量的關係。
• 11、消費者在食用前之處理。
• 12、改進全球對新型致病菌的監測。