In October 2013, Porcine epidemic diarrhea (PED) was confirmed in Japan for the first time in seven years. Since then, the outbreak has spread nationwide, and more than new 100 cases per week were confirmed in April 2014 when the largest number of cases was confirmed. Then, the number of new cases started to decline and, so far, 822 cases in total have been confirmed in 39 prefectures as of 31 October. Under the circumstances, the Ministry of Agriculture, Forestry and Fisheries has been implementing actions to prevent further PEDV spread, for instance, by carrying out thoroughly the control measures based on the interim report on the epidemiological investigation and the comprehensive guidelines on PED control publicized this October.

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A large-scale outbreak of porcine epidemic diarrhea (PED) has been observed in Japan in 2013 after seven years absence. Above 1.2 million pigs have shown typical symptoms such as anorexia, vomiting and watery diarrhea, and approximately 380,000 pigs have died from October 2013 through August 2014. Several virus strains have been successfully isolated from the affected piglets during outbreak of PED. Sequence analyses of the 2013-2014 strains indicated that these were genetically distinct from the strains reported previously in Japan, but were related to the strains recently circulating in the US, Korea and China. It is suggested that PED virus strains detected almost simultaneously in the US, Korea, China and Japan are derived from the common origin. New strains have probably invaded from overseas and rapidly spread throughout Japan since 2013. Further full-genomic analysis of the current field strains in Japan will be required to clarify the global spread and evolutionary dynamics of emerging PEDV strains.

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New Porcine Epidemic Diarrhea (PED) began occurring in Asia in the 2010s. The PED spread to United States, Canada, Mexico, Korea, Taiwan and Japan during 2013 and 2014. PED occurred for the first time in the United States in April, 2013. The United States was a PED-free country until then, and pigs in the United States did not have immunity against it. Therefore infections of the PED virus in the United States caused the deaths of millions of piglets. On the other hand, in Japan, an outbreak of PED occurred in the 1990s, and a live vaccine for PED has been already approved. There were the sporadic occurrences of PED in Japan, but there was no full-blown outbreak, so it seemed that PED was under control in Japan. However, another outbreak of PED occurred in Japan in 2014. In this report, I focus on the background of this outbreak and describe the PED.

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兵庫県の山間部に生息する野生のホンシュウジカにおけるSarcocystis属原虫の感染率について調査した。捕獲した1歳未満から5歳齢までの64頭について，心筋，横隔膜，後肢運動筋，背部最長筋の各部位を調査した結果，52頭（81.3%）からSarcocystisのシスト（サルコシスト）が検出された。年齢別では，1歳未満の個体を除く1歳令から5歳令までの個体ではお互いの感染率間に有意な差は認められなかったが，1歳未満の個体ではすべてでサルコシストが認められなかった。寄生部位別では，背部最長筋での寄生率が他の部位と較べて有意に低かったが，その他の部位間では有意差は認められなかった。採材した筋肉10gあたりのサルコシスト数は心筋での値が他の部位に較べて有意に高かった。ホンシュウジカにおけるSarcocystisの感染率はこれまでに報告されている群馬県および埼玉県の個体でも高いことが報告されており，この高い感染率はわが国全体に拡がっているものと推測された。今回得られたサルコシストは卵円形ないし桿状を呈し，大きさは平均698.5×170.2μmであった。

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PROP1は，下垂体特異的に発現する転写因子であり，PRL・GHなどの産生を調節している。本研究は，PROP1遺伝子プロモーター領域に存在する4種類の多型を同定し，雌豚の繁殖形質との相関解析を実施した。供試動物は，Landrace種とLarge Whiteとの交雑種267頭を用いた。繁殖成績は，総産子数・生存産子数・死亡子豚数・白子数・ミイラ子豚数・妊娠期間・授乳期間・補正21日齢一腹子豚体重・離乳後初回交配日数・初回交配日齢を抽出した。更に1産と2産を合計した総産子数および生存産子数について解析した。g. -442 G>C多型は，1産における総産子数および生存産子数に，1産と2産を合計した生存産子数において有意な関連性を示した（P<0.05）。それ以外の多型は，繁殖形質と関連性はなかった。以上のことから，ブタPROP1遺伝子プロモーター領域に存在するSNP（g. -442 G>C）は，早期産次の産子数に関連していると考察した。

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This is the report of Avian influenza seminar held in Tokyo University on August 28^th, as 40^th scientific seminar of the Japan Society of Veterinary Epidemiology. Two lectures are included here ; “Controlling Avian Influenza With and Without Vaccination” by Dr Davis Swayne (USDA), and “Event-based and Active Surveillance for Avian Influenza” by Dr Cristobal Zepeda (USDA). Dr Swayne recommended the targeted vaccination program with the combination of appropriate surveillance to watch the immunity level of the targeted population and effectiveness of the vaccine strain to the field strain, in the case when the AI control with vaccination is needed. Dr Zepeda explained the AI surveillance, focusing two types ; Indicator-based, and Event-based surveillance. Event-based surveillance is currently being incorporated in surveillance system as a complement to Indicator-based surveillance. He also mentioned the roll of veterinary epidemiologist in planning and interpretation of surveillance, and application of the outcome to the decision-making.

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HACCP system is very effective system to control food safety hazards during food production and processing. Japan introduced this system since 1995, as voluntary system in the five food categories, those are milk and milk products, processed meat products, soft drinks, canned and retort foods, fish products. However, as it is voluntary system, 80% companies introduced this system, but only 25% of small and less developed food producing companies introduced this system. Therefore, Japanese government revised Japanese Food Sanitation Law, HACCP system is able to selectively introduce HACCP system in all categories of foods, instead of general hygiene management. HACCP system will be mandatory in all kinds of food in next ten years.

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