Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand.
Center of Excellence for Food and Water Risk Analysis (FAWRA), Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.
Zoonoses Public Health. 2022 Sep;69(6):625-634. doi: 10.1111/zph.12951. Epub 2022 May 3.
A cross-sectional study evaluated the risk of zoonotic Streptococcus suis (S. suis) illness from consuming raw pork and swine blood in Nakhon Sawan Province. A four-step risk assessment recommended by the Codex Alimentarius Commission was used to evaluate the risk along the pork supply chain. A total of 480 pork and swine blood samples were collected from the abattoir (n = 120) and retail (n = 360) during December 2020 and January 2021. Streptococcus suis in samples was enumerated using a culture-based technique and then confirmed by the biochemical and molecular technique. Streptococcus suis was serotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Two positive swine blood samples were contaminated with non-zoonotic S. suis serotype 23 at retail. In the case of all negative samples, the deterministic prevalence becomes zero and then the risk could not be estimated. Otherwise, the beta probability distribution was used to describe the probabilistic prevalence, while the maximum likelihood estimator was applied to estimate the upper limit of a probability distribution of concentration. The district averages of probabilistic prevalences of zoonotic S. suis in pork products at abattoir and retail were 9.9% and 4.1%, respectively. The district averages of concentrations of zoonotic S. suis in pork and blood samples from abattoir were 6.8 × 10 cfu/g and 6.83 cfu/ml and in pork and blood samples from retail were 2.3 × 10 cfu/g and 2.30 cfu/ml, respectively. The overall annual risk estimate per 100,000 population in pork and swine blood from abattoir and retail were 9.8 × 10 , 2.2 × 10 , 5.4 × 10 , and 8.3 × 10 . These risk estimates were negligible (<10 ) except for the annual risk estimate in swine blood from the abattoir. The results from this cross-sectional risk assessment should prompt the food safety regulator to cautiously sample by taking into account the duration of sampling and sample size.
一项横断面研究评估了在那空沙旺省食用生猪肉和猪血感染人畜共患猪链球菌（S. suis）病的风险。采用食品法典委员会推荐的四步风险评估法沿猪肉供应链评估风险。2020 年 12 月至 2021 年 1 月期间，共从屠宰场（n=120）和零售点（n=360）采集 480 份猪肉和猪血样本。使用基于培养的技术对样本中的猪链球菌进行计数，然后通过生化和分子技术进行确认。使用基质辅助激光解吸/电离飞行时间质谱法对猪链球菌进行血清分型。在零售点，有两份阳性猪血样本受到非人畜共患血清型 23 的猪链球菌污染。在所有阴性样本的情况下，确定性流行率为零，因此无法进行风险估计。否则，使用β概率分布来描述概率流行率，同时应用最大似然估计来估计浓度概率分布的上限。屠宰场猪肉产品中人畜共患猪链球菌的概率流行率区平均值分别为 9.9%和 4.1%。屠宰场猪肉和猪血样本中人畜共患猪链球菌的浓度区平均值分别为 6.8×10 cfu/g 和 6.83 cfu/ml，零售点猪肉和猪血样本中分别为 2.3×10 cfu/g 和 2.30 cfu/ml。屠宰场和零售点的猪肉和猪血每年每 10 万人的总风险估计分别为 9.8×10 ，2.2×10 ，5.4×10 ，8.3×10 。这些风险估计值都可以忽略不计（<10 ），除了屠宰场猪血的年风险估计值。此横断面风险评估的结果应促使食品安全监管机构谨慎采样，考虑采样持续时间和样本量。
