Campylobacter food poisoning is one of the major bacterial foodborne diseases resulting in numerous outbreaks worldwide. Particularly in Japan, one-fourth of the total food poisoning is caused by Campylobacter jejuni/coli. Raw and/or undercooked poultry meat and meat products are known as the main cause of campylobacteriosis. Consequently, effective and immediate actions are needed to eliminate or at least reduce campylobacteriosis. This study aimed at examining the Japanese food regulation system, comparing it with those in the USA and Australia, and making necessary recommendations for a better control of campylobacteriosis in Japan. The study was conducted by a thorough investigation of published literatures, governmental documents, statistical and epidemiological data and public information. The results led to recommendations that the Japanese food regulation authority should consider the following suggestions in order to control campylobacteriosis: 1) assess the Campylobacter safety at the end of processing stage of chicken supply chain based on risk assessment using quantitative/qualitative baseline data collected over Japan, 2) establish a national Campylobacter strategy, including specific campylobacteriosis reduction goals and criteria, and 3) provide the small food business operators with sufficient training and support to implement a Hazard Analysis Critical Control Points (HACCP) as an obligatory food safety requirement. It is acknowledged that it would be difficult to apply foreign regulations directly to Japanese food regulation system due to differences in food culture, regulation, industry structure, and data collection systems. Thus, flexible application is required. Finding and conducting effective Campylobacter control measures can decrease contaminated live birds and chicken meat in Japan, home to a unique food culture of eating raw and/or undercooked chicken meat called Torisashi such as sashimi, tataki and yubiki chicken. Consequently, potentially available research data may be instrumental in finding solutions for reducing campylobacteriosis. Eliminating Campylobacter food poisoning cases in Japan will be a significant achievement in ensuring Japanese and global food safety.

This study aimed at investigating antimicrobial resistance (AMR) profile of Vibrio parahaemolyticus (V. parahaemolyticus). The bacteria were isolated from wild-caught and farmed Japanese horse mackerel (Trachurus japonicus), and examined for the antimicrobial drug resistance. Furthermore, the serotype, and the genes of thermostable direct hemolysin (tdh) and cholera toxin transcriptional activator (toxR) of the isolates were investigated by using a serotype testing kit and PCR method. Eighty-eight and 126 V. parahaemolyticus strains were isolated from wild-caught and farmed Japanese horse mackerel, respectively. Ten and 18 distinct serotypes were detected from wild-caught and farmed Japanese horse mackerel. All strains were negative for tdh genes but positive for toxR genes. Resistances to ampicillin (ABP) and to both ABP and fosfomycin (FOM) were observed in 54 and 23 strains from the wild-caught fish, while those resistant strains from farm fish were 112 and 7 strains. Multidrug-resistance to three or four drugs including ABP was observed in one or two strains from the wild-caught fish.

These results strongly suggest that the environmental exposure of antimicrobial drugs results in the spread of resistant genes in Japanese horse mackerel. This study highlights the need for monitoring the spread of resistance genes to the human intestinal flora as well as to other bacteria in the environment.

Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) are leading causes of foodborne gastroenteritis in Japan. Epidemiological surveillance has provided evidence that poultry meat is one of the main reservoirs for human campylobacteriosis, and therefore, improvement in process hygiene at slaughter is required to reduce the number of human infections. This study thus aimed to develop fluorescent immunochromatography strips for rapid and sensitive detection of thermophilic Campylobacter on poultry carcasses at slaughter. To establish the required detection levels, we first determined the numbers of C. jejuni and C. coli on poultry carcasses at one large-scale poultry slaughterhouse in Japan, resulting in the detection of Campylobacter at 1.97 ± 0.24 log CFU/25 g of neck skin during the post-chilling process by using ISO 10272-2:2017. Our developed Campylobacter fluorescence immunochromatography (FIC) assay exhibited a 50% limit of detection of 3.51 log CFU or 4.34 log CFU for C. jejuni NCTC 11168 or C. coli JCM 2529, respectively. Inclusive and exclusive tests resulted in good agreement. The practical usefulness of this test toward poultry carcasses should be evaluated in future studies, perhaps concentration of the target microorganisms prior to the testing might be helpful to further enhance sensitivity. Nevertheless, our data suggest the potential of FIC for rapid and sensitive detection of thermophilic Campylobacter for monitoring the process hygiene of poultry carcasses at slaughter.