The aim of this is to identify, as hypotheses, all feasible sources and routes of infection for the cases in , and to the probability of each hypothesis. The strategy of this is as follows. 1) risk status in is tentatively divided into 3 stages, i.e., before 1996 April when administrative guidance for feed ban of cattle MBM introduced. After that to 2001 September, the first case of in , then, after 2001 October with real feed ban in the law. 2) Make hypotheses depending on the invasive risk scenarios and propagation risk of in , and they are checked by evidences, case control or statistics. 3) Grouping of cattle was conducted time sequentially and spatially; that is Group-A (1995-96, born in Hokkaido, Kanto), Group-B (1999 in Kyushu), Group-C (1999-2001 in Hokkaido), Group-D (young cattle born after real feed ban) and Pre-A, Post-D groups. As a result, a milk replacer was considered one of the most probable cause of group-A contamination, and group-C might be caused by an indigenous propagation of group-A in Hokkaido. If the hypothesis of Holland animal fat as causative material was accepted, however, there are several unexplainable points. Collection of scientific evidences on animal fat impurity and age dependent susceptibility to will be needed to clarify the true causative material.

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BACKGROUND: Trend of the mortality rate of Creutzfeldt-Jakob disease (CJD) in is still unclear. This aimed to estimate annual crude mortality rates due to CJD and examine the CJD mortality trend in during the period of 1979-2004.
METHODS: National death certificate data on CJD were used (CJD coded as 046.1 for ICD-9 and A81.0 for ICD-10). Trends in age-standardized mortality rates for CJD were examined by using time series analyses including the joinpoint regression analysis.
RESULTS: A total of 1,966 deaths (862 males and 1,104 females) were identified with CJD coded as the underlying-cause-of-death. The annual number of deaths and crude mortality rates peaked in 2004 at 163 (66 for males and 97 for females) deaths and 1.28 (1.06 for males and 1.48 for females) deaths per million population per year, respectively. The age-specific mortality rates rapidly increased with age between 50 and 74 years, especially among females, and sharply declined at 80+ years. Throughout the observed period, there were no significant change points, and the annual percentage changes (95% confidence intervals) were +3.09 (2.18 - 4.02) % for males and +3.90 (2.98-4.83) % and females. The total number of CJD deaths under 50 years of age was 131, and there was found no increase in the annual number of deaths for the past few years in this age group.
CONCLUSION: CJD mortality in trend data based on death certificates has significantly increased in during the period of 1979-2004.
J Epidemiol 2007; 17: 133-139.

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The occurrence of Bovine Spongiform Encephalopathy (, so called mad cow diseases) that was first identified in England in 1986 was considered as being limited to only European countries, including England. However, the in Asia as well as North America since 2001 has amplified the fear that there isn't any nation in the world that is a safe area. In order to assess the risk of in each country, the Office International des Epizooties (OIE) and EU have respectively established criteria, where OIE has set 5 levels and EU has set 4 levels. The Scientific Steering Committee (SSC) of the European Commission conducted a Geographical Risk(GBR) assessment for 64 nations, such as the United States, etc., as of April 29, 2003. However, as of July 1, 2005, the duty of GBR assessment is expected to be transferred to a newly established body called EFSA (European Food Safety Authority, located in Parma, Italy). As Korea has not undergone a GBR assessment up to now, this analyzed the risk of in Korea by reviewing prevention measures, etc., that have been put in place. This shall be a barometer for estimating the GBR assessment level of Korea.

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In recent years, food-related issues have become increasingly more publicised in developed countries. This holds true for where food-related issues have been drawing attention as a socially significant topic, particularly since the appearance of (Bovine Spongiform Encephalopathy). In 2003 a new governmental office, the Food Safety Commission was established in the Cabinet Office of the Japanese Government based on a new law, “the Food Safety Basic Law”. This change of administration was raised by the of , which is considered to be a drastic reformation of food safety policy in .
In addition, impact was significant not only on administration but also on the agriculture and food industries. It revealed to the public lots of holes in the food related system which have been concealed for years.
In this paper, I would like to show the inadequacy of management before the of and the subsequent governmental actions and reactions for food safety. Furthermore, problems that still remain after the reformation, such as ban on US beef and policy of blanket testing, will be discussed.

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Chronic wasting disease (CWD) is a prion disease of cervids such as deer and elk in North America. Unlike other transmissible spongiform encephalopathy (TSE) such as scrapie, CWD occurs in both captive and wild ranging animals, but not in domestic ruminants such as sheep and cattle. In this paper, the history of the disease, pathogenesis of CWD, susceptibility of animals, its transmission mechanisms, potential origins of the disease, diagnostic methods in the field and laboratory tests, surveillance and survey systems in the USA and Canada, control strategies, economic impact of the disease, food and feed safety, and the risks in human and animals are reviewed and summarized. Although there is no evidence that CWD has been transmitted to humans, it may have the potential to infect humans.

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Background: Hardships associated with the ongoing coronavirus disease 2019 (COVID-19) pandemic can affect mental health, potentially leading to increased risk of suicide. We examined the relationship between the COVID-19

and suicide attempts in Okayama, using information from emergency dispatches.

Methods: This was a descriptive

. We collected information on emergency dispatches in Okayama City and Kibichuo from March to August in 2018, 2019, and 2020 (n = 47,770 cases). We compared emergency dispatches and their demographic characteristics, especially focusing on suicide attempts, during these 3 years.

Results: The number of emergency dispatches in 2020 decreased compared with the previous 2 years, while the number and proportion of emergency dispatches related to suicide attempts increased. This increase was more pronounced among women and those aged 25–49 years. Among women aged 25–49 years, there was a cumulative total of 43 suicide attempts in 2018 and 2019 and 73 suicide attempts in 2020.

Conclusions: The number and proportion of emergency dispatches related to suicide attempts increased in 2020 compared with the previous 2 years, especially among women and those aged 25–49 years. This increase may be partly explained by hardships, such as economic losses or reduced social ties, during the COVID-19

.

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Since the advent of bovine spongiform encephalopathy () in the United Kingdom in 1986, new cases have recently become rare. However, in and the United States, positive cases have started to be seen recently. The rise in cases paved the way for the human form of this disease, the variant Creutzfeldt-Jakob disease (vCJD). The observed trends in the UK may be attributed to effective implementation of public health policies coupled with increased vigilance through advancement in science and technology, or they may well be a reflection of the natural disease progression. We aim to discuss the chronology of events, and compare examination methods, costs and cost-efficiency, management, and public policies of , Europe, and the USA.

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An of a disease with parapox-like symptoms was reported in South Korea in April 2012. Three of 45 Korean native cattle, age 20–24 months, were affected. Parapoxviruses were detected and identified by electron microscopy and polymerase chain reaction (PCR). To determine the genetic characteristics of the Korean strains, the sequence of the major envelope protein (B2L) was determined and compared with published reference sequences. Phylogenetic analysis revealed that the parapoxvirus strains were closely related to not only isolates from , but also isolates from Germany, Sudan and the United states. This is the first report on an and the molecular characterization of BPSV in Korea.

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A five-month-pregnant Suffolk sheep histologically diagnosed as spontaneous scrapie was studied. Western blot analysis was performed with rabbit serum against the sheep scrapie-associated fibrils (SAF). In the proteinase K (pk)-treated parental brain and spleen samples, three major bands (15K, 18K, and 23K) were detected. These major bands were not detected from the placenta. Infectious agents were isolated in mice from the brain samples but not from the placental homogenates. In another case of a three-month-pregnant Corriedale sheep without any clinical sign of, but histologically diagnosed as scrapie, was also studied in a similar approach. In the parental brain samples, three major bands (15K, 18K and 23K) were detected. SAF protein was not detected in the parental spleen and placenta. No bands reactive with the antiserum were detected in any other samples from the fetal brain and spleen in both cases. However, infectious agents were isolated in mice from both brain and placental homogenates. Since the placenta is an important site of natural infection, it is worthwhile to these tissues for the of scrapie infection.

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Important animal diseases, such as , highly pathogenic avian influenza and foot and mouth disease, occurred in in recent years. These diseases severely damaged livestock industries and also increased social concerns about food safety and public health. With increasing the importance of animal health in the general public as well as the livestock industries, the role of “epidemiology” has been expected as a useful tool to understand and analyze disease situations and to support decision making for control and prevention of animal diseases. To meet these expectations, the veterinary epidemiology training course for local and national veterinary officials in working for animal health is held annually. The training course is sponsored by the Ministry of Agriculture, Forestry and Fisheries, and managed by the National Institute of Animal Health. The aim of this training course is to provide basic principles and skills of veterinary epidemiology applicable to animal disease control activities. During the training course, trainees firstly learn basic methods to analyze and interpret field data, to evaluate diagnostic tests, and to design observational studies and surveys using sampling methods. Then, they learn how to apply basic methods to problems through practical exercises. These include investigations and studies of diseases in animal populations. This training course provides good opportunities to brush up and develop appropriate knowledge and skills of epidemiology for veterinarians in the animal health field.

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Methicillin-resistant Staphylococcus aureus (MRSA) is the leading cause of nosocomial infection and MRSA outbreaks have become a major problem. Therefore, the rapid and accurate typing of MRSA isolates is important for surveys and nosocomial infection control. Pulsed-field gel electrophoresis (PFGE) is considered as the gold standard technique for MRSA typing, because of its high discriminatory power, but its procedure is rather complicated and time-consuming. The spa gene encodes a cell wall component of Staphylococcus aureus protein A, and exhibits polymorphism. Sequencing the spa gene is expected superior to PFGE in speed and data interpretation. In the present , we evaluated whether spa typing of MRSA is useful for nosocomial analysis and investigations. We analyzed 19 nosocomial isolates from 4 separate hospitals and 26 isolates from outpatients of Toyama University Hospital. Either PFGE or spa typing revealed a single nosocomial strain that appears unique to each hospital. Indeed, spa typing confirmed the four different strains, but PFGE demonstrated only 3 strains. With the total 45 isolates, PFGE showed 16 different patterns and spa typing showed 12 patterns. Moreover, we were able to analyze the spa gene in about 2 days, from sampling to obtaining the results, whereas it took about 7 days with PFGE. In conclusion, sequence-based spa typing shows comparable sensitivities to PFGE, and is a rapid and easy handling method. The sequence-based spa typing can be used as the rapid screening test when MRSA is suspected in areas and hospitals.

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The subject of this paper is to estimate consumers' welfare loss when the testing age criterion for cattle is revised from all months to older than 21 months, by analyzing the change in meat demand due to this revision. However this analysis is different from ordinary revealed preference methods in that the demand data after this policy change are stated, while the data before this change are revealed as usual. This is because this paper focuses on a policy change which is not substantially executed yet. Using this demand data I estimated the generalized corner solution model of Phaneuf et al. (2000) for an incomplete demand system model. When I simulated each monitor's welfare loss based on the model estimation result, the expected compensating variation per household per month was 214 yen at the sample mean and 55 yen at the sample median.

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As the foods are stocked below freezing and widely distributed, a kind of food-borne which occurs in separate regions or in different time, so called “diffuse ”, has been found at the present day. Unless the is early recognized, the number of victims would increase. Some methods have been developed to analyze the relatedness of bacteria isolated from the patients of enteric infections. PFGE, pulsed-field gel electrophoresis, is one of the methods and powerful to discriminate the difference in nucleotide sequences among bacterial genomes. Availability of PFGE analysis is appreciated to examine the linkage of each incident of food-borne infections in investigation. A PFGE network, PulseNet , is now under construction among National Institute of Infectious Diseases, local Health Institutes and Ministry of Health, Labour and Welfare.

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The Food Safety Commission (FSC) of , established in July 2003, has its own initiative to conduct risk assessments on food stuffs known as “self-tasking assessment”. Within this framework, the FSC decided to conduct a risk assessment of beef and beef offal imported into from countries with no previous reports; thus, a methodology was formed to suit to this purpose. This methodology was partly based on the previous assessments of Japanese domestic beef and beef imported from U.S.A./Canada, but some modifications were made. Other organizations’ assessment methods, such as those used for status assessment in live cattle by the OIE and EFSA’s GBR, were also consulted. In this review, the authors introduce this alternative methodology, which reflects (1) the risk of live cattle in the assessed country including temporal risks of invasion and domestic propagation, with the assessment results verified by surveillance data, and (2) the risk of beef and beef offal consisting of cumulative risk by types of slaughtering and meat production processes implemented and the status of mechanically recovered meat production. Other possible influencing factors such as atypical cases were also reviewed. The key characteristic of the current assessment is a combination of the time-sequential risk level of live cattle and qualitative risk level of meat production at present in an assessed country.

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Background: Countermeasures against COVID-19

, such as lockdowns and voluntary restrictions against going out, adversely affect human stress and depress economic activity. Particularly, this stress might lead to suicide. Object: We examined excess mortality attributable to COVID-19 related suicide. Method: We applied the National Institute of Infectious Diseases (NIID) model to suicide deaths, by gender, throughout during October 2009–January 2021. Effects of the great earthquake that struck eastern on March 11, 2011 were incorporated into the estimation model. Results: Significant excess mortality from suicide was found during July–January for both genders. Its frequency was higher among females than among males. In total, 2276 cases of excess mortality were identified. Discussion and Conclusion: Excess mortality during the four months was more than twice that of COVID-19 deaths confirmed by PCR testing. Countermeasures against COVID-19 should be chosen carefully in light of suicide effects.

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Preface and Objectives
 Cholera has recently become more serious in African countries. In southern Africa, a serious cholera was reported in 2008. Here we investigate Vibrio cholerae in aquatic environments, rivers, tube well waters, fish tissues, and aquatic plants in Zambia.
Methods
 The sampling was conducted on Kafue and Zambezi rivers as well as at public wells. The samples included river water, mud, fish, floating grass, and well water. All samples were enriched in alkaline peptone water (APW) and streaked on thiosulfate citrate bilesalts saccharos (TCBS) Vibrio agar. Some types of colonies were isolated using polymyxin mannose tellurite (PMT) agar. All water samples were analyzed for enterobacteria as well as vibrio contamination. River and shallow tube well water samples were analyzed for E. coli.
Results
 Samples, including fish tissues, river, and tube well waters, except for the fish intestines, were found to be contaminated with vibrios when cultured on TCBS Vibrio agar.
 Deep tube well water was not contaminated with vibrios or E. coli. V. cholerae El Tor was not detected through sampling and culturing on PMT agar. E. coli was detected in river and shallow tube well water samples.
Discussion
 Vibrios were detected in Zambia’s aquatic environments. Cholera may occur. Vibrio contaminations in fish have been reported from Bangladesh, Laos, Kenya, and India. Fish is a good source of protein to improve person’s nutritional status. However, it must be treated properly so that any contamination of residential areas is avoided. Therefore, people must pay attention to fish.
Conclusion
 Here several types of V. cholerae were isolated from different aquatic environments. Fish is a nutritious diet, but contaminated Vibrios fish must be treated so that it will not contaminate residential areas. We must investigate the gateway of cholera outbreaks in Zambia.

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Bovine spongiform encephalopathy (

) is a fatal neurodegenerative disease that belongs to transmissible spongiform encephalopathy (TSE). Since the first case was identified in the UK in 1986, spread to other countries including . Its incidence peaked in 1992 in the UK and from 2001 to 2006 in many other countries, but a feed ban aimed at eliminating the recycling of the agent and other control measures aimed at preventing food and feed contamination with the agent were highly effective at reducing the spread of . In 2004, two types of atypical , H-type (H-) and L-type (L-), which differ from classical (C-), were found in France and Italy. Atypical , which is assumed to occur spontaneously, has also been detected among cattle in other countries including . The agent including atypical agent is a unique food-safety hazard with different chemical and biological properties from the microbial pathogens and toxic chemicals that contaminate food. In this review, we summarize the reported findings on the tissue distribution of prions in infected cattle and other aspects of , as well as the control measures against the disease employed in . Topics that require further studies are discussed based on the summarized findings from the perspective of food safety.

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