Decreasing trend of ß-lactam resistance in Salmonella isolates from broiler chickens due to the cessation of ceftiofur in ovo administration.

Ceftiofur, a third-generation cephalosporin antimicrobial, was used in Japanese hatcheries for many years before 2012. We continue to study Salmonella in broilers and their antimicrobial resistance. The current study aimed to express how the cessation of ceftiofur affects the antimicrobial resistance of Salmonella isolated from broiler chickens in Kagoshima Prefecture, Japan in 2017 and 2018. A total of 274 Salmonella isolates were recovered from 1535 cecal content samples obtained from 96 broiler flocks over years 2017 and 2018. Among the S. enterica isolates, the predominant serovars were S. Manhattan (128/274, 46.7%), S. Schwarzengrund (120/274, 43.8%), and S. Infantis (26/274, 9.5%). The isolates showed a high proportion of antimicrobial resistance for oxytetracycline, sulfamethoxazole, and streptomycin. However, the ß-lactam resistance rates were significantly decreased (p < 0.01) in 2017, while no ß-lactam resistant isolates detected in 2018. The highlight of this study was the complete disappearance of ß-lactam resistance in Salmonella isolates from broiler chicken in Kagoshima, Japan.

Increased Salmonella Schwarzengrund prevalence and antimicrobial susceptibility of Salmonella enterica isolated from broiler chickens in Kagoshima Prefecture in Japan between 2013 and 2016.

This study aimed to analyze the Salmonella serovars, measure the minimum inhibitory concentration of antimicrobials, and examine the antimicrobial resistance genes of Salmonella isolated from 192 broiler flocks in Kagoshima Prefecture in Japan, from 2013 to 2016. We found that all Salmonella isolates belonged to three serovars: Salmonella Manhattan, S. Infantis, and S. Schwarzengrund. Among them, S. Schwarzengrund prevalence has recently increased annually making the main serovar. Most recovered isolates were highly resistant to streptomycin, sulfamethoxazole, and oxytetracycline. We saw the reduction of third-generation cephalosporin resistance and identified the reason of increased kanamycin resistance to be the increased number of S. Schwazengrund isolates. Among the kanamycin-resistant Salmonella isolates, aphA1 constituted the main resistance gene detected.

Prevalence of Salmonella in broiler chickens in Kagoshima, Japan in 2009 to 2012 and the relationship between serovars changing and antimicrobial resistance.

BACKGROUND: This study aimed to examine the prevalence, serovars, and antimicrobial resistance of Salmonella isolates from broiler chickens in Kagoshima, Japan. A total of 192 flocks and 3071 samples were collected from broiler chickens at local farms in Kagoshima, Japan from 2009 to 2012. RESULT: Among the tested farms, 49.0% of flocks were positive for Salmonella, and 243 isolates were obtained from 3071 cecal samples (7.9%). All the Salmonella isolates were one of three serovars: S. Infantis (57.6%); (140/243), S. Manhattan (40.3%; 98/243 and S. Schwarzengrund (2.1%; 5/243). The proportion of S. Infantis isolates decreased from 66.0% in 2009 to 50.0% in 2011 but increased to 57.6% in 2012, while the proportion of S. Manhattan isolates significantly increased from 26.4 to 50% from 2009 to 2011, and decreased moderately to 40.9% in 2012. Most of the recovered Salmonella isolates were resistant to three antimicrobials, i.e., streptomycin (95.1%), sulfamethoxazole (91.0%) and oxytetracycline (91.4%). In contrast, all Salmonella strains were susceptible to chloramphenicol. Comparison of this study to previous studies of the antimicrobial susceptibility of Salmonella isolates showed that: the percentage of antibiotic-resistance isolates increased dramatically for two antibiotics, ampicillin (from 22.4 to 55.1%) and cefotaxime (from 9.1 to 52.7%). In contrast, the percentage of ofloxacin-resistant isolates decreased across the three survey periods, from 20.8% in 2004-2006 to 1.6% in the present study period (2009-2012). In addition, S. Infantis exhibited a variety of resistance to antimicrobials examined from sensitive to resistance to eight antimicrobials. Multidrug resistance to more than 6 six antimicrobials was detected in 113 (46.5%) of the isolates, and most of them were S. Manhattan. CONCLUSIONS: There was a marked change in the serovars and antimicrobial resistance profiles of the Salmonella isolates in this study compared to those in previous studies. The percentage of S. Manhattan isolates increased as did the percentages of ampicillin- and cefotaxime-resistant isolates.

Identification of Biological Hazards in Produce Consumed in Industrialized Countries: A Review.

Microbial contamination of fresh produce (fresh fruits and vegetables) poses serious public health concerns worldwide. This study was conducted as a comprehensive analysis of biological hazards in the global fresh produce chain. Data about produce-related outbreaks and illness were collected from the annual reports and databases of foodborne outbreak surveillance systems in different regions and countries from 2010 to 2015. The global patterns of and regional differences in documented outbreaks and cases were analyzed, and produce commodities and pathogens of greatest concern were identified. Data on sporadic illnesses were also collected through a comprehensive literature review of case-control studies. We found 988 produce-related outbreaks (with known agents) and 45,723 cases in all regions and countries. The numbers of produce-related outbreaks per million person-years were approximately 0.76, 0.26, 0.25, 0.13, 0.12, and 0.05 in New Zealand, Australia, the United States, the European Union, Canada, and Japan, respectively. The top three food categories and pathogens contributing to produce-related outbreaks were vegetables and nonfruits (i.e., food other than fruits; 27.0%), unspecified vegetables (12.2%), and vegetable row crops (11.7%) and norovirus (42.4%), Salmonella enterica (19.9%), and Staphylococcus aureus (7.9%), respectively. Produce consumption was identified as a protective factor, a risk factor, and either a protective or risk factor for sporadic illnesses in 11, 5, and 5 studies, respectively, among 21 case-control studies. Risks associated with produce consumption in the United States and the European Union have been linked to various factors such as irrigation water, cross-contamination, storage time and temperature abuse, infected food handlers, and unprocessed contaminated ingredients. The results of the current study indicate the complexity of produce products consumed across the globe and the difficulty in tracing illnesses back to specific food ingredients.

[Trends of food poisonings caused by natural toxins in Japan, 1989-2011].

In order to reduce the health risk associated with food poisonings caused by natural toxins, it is necessary to implement risk management strategies based on previous poisoning data and risk factors. In present study, we statistically analyzed natural toxin food poisoning (NTFP) data published by the Ministry of Health, Labour and Welfare from 1989 to 2010 in Japan and reviewed the trends of NTFP for each natural toxin hazard. Since 1989, the number of incidents of NTFP in each year has not been reduced. Prevention and control are needed to reduce the risk of NTFP. The major site for all hazards was "at home". This result suggested that consumer education is critically important to inform about NTFP occurrence, preventive measures and emergency treatments. Furthermore, countermeasures for NTFPs which have never occurred in the past in Japan should be considered, because of the increasing variety of imported foods and changes resulting from the inerease of sea temperature with global warming.

Estimating the burden of acute gastroenteritis and foodborne illness caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus by using population-based telephone survey data, Miyagi Prefecture, Japan, 2005 to 2006.

Most cases of acute gastroenteritis and foodborne disease are not ascertained by public health surveillance because the ill person does not always seek medical care and submit a stool sample for testing, and the laboratory does not always test for or identify the causative organism. We estimated the total burden of acute gastroenteritis in Miyagi Prefecture, Japan, using data from two 2-week cross-sectional, population-based telephone surveys conducted in 2006 and 2007. To estimate the number of acute gastroenteritis illnesses caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus in Miyagi Prefecture, we determined the number of cases for each pathogen from active laboratory-based surveillance during 2005 to 2006 and adjusted for seeking of medical care and submission of stool specimens by using data from the population-based telephone surveys. Monte Carlo simulation was used to incorporate uncertainty. The prevalence of acute gastroenteritis in the preceding 4 weeks was 3.3% (70 of 2,126) and 3.5% (74 of 2,121) in the winter and summer months, yielding an estimated 44,200 episodes of acute gastroenteritis each year in this region. Among people with acute gastroenteritis, the physician consultation rate was 32.0%, and 10.9% of persons who sought care submitted a stool sample. The estimated numbers of Campylobacter-, Salmonella-, and V. parahaemolyticus -associated episodes of acute gastroenteritis were 1,512, 209, and 100 per 100,000 population per year, respectively, in this region. These estimates are significantly higher than the number of reported cases in surveillance in this region. Cases ascertained from active surveillance were also underrepresented in the present passive surveillance, suggesting that complementary surveillance systems, such as laboratory-based active surveillance in sentinel sites, are needed to monitor food safety in Japan.

Quantitative risk assessment of Vibrio parahaemolyticus in finfish: a model of raw horse mackerel consumption in Japan.

The aim of this study was to evaluate the effects of implemented control measures to reduce illness induced by Vibrio parahaemolyticus (V. parahaemolyticus) in horse mackerel (Trachurus japonicus), seafood that is commonly consumed raw in Japan. On the basis of currently available experimental and survey data, we constructed a quantitative risk model of V. parahaemolyticus in horse mackerel from harvest to consumption. In particular, the following factors were evaluated: bacterial growth at all stages, effects of washing the fish body and storage water, and bacterial transfer from the fish surface, gills, and intestine to fillets during preparation. New parameters of the beta-Poisson dose-response model were determined from all human feeding trials, some of which have been used for risk assessment by the U.S. Food and Drug Administration (USFDA). The probability of illness caused by V. parahaemolyticus was estimated using both the USFDA dose-response parameters and our parameters for each selected pathway of scenario alternatives: washing whole fish at landing, storage in contaminated water, high temperature during transportation, and washing fish during preparation. The last scenario (washing fish during preparation) was the most effective for reducing the risk of illness by about a factor of 10 compared to no washing at this stage. Risk of illness increased by 50% by exposure to increased temperature during transportation, according to our assumptions of duration and temperature. The other two scenarios did not significantly affect risk. The choice of dose-response parameters was not critical for evaluation of control measures.

The human health burden of foodborne infections caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus in Miyagi Prefecture, Japan.

To estimate the human health burden of foodborne infections caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus in Japan, an epidemiological study was conducted in Miyagi Prefecture. Laboratory-confirmed infections among patients with diarrhea caused by the three pathogens were ascertained from two clinical laboratories in the prefecture from April 2005 to March 2006. To estimate the number of ill persons who were not laboratory-confirmed, we estimated physician-consultation rates for patients with acute diarrhea by analyzing foodborne outbreak investigation data for each pathogen and the frequency at which stool specimens were submitted from a physician survey. Each factor was added to a Monte-Carlo simulation model as a probability distribution, and the number of laboratory-confirmed cases was extrapolated to estimate the total number of ill persons. The estimated incidence of foodborne infections per 100,000 per year in this region estimated by this model was 237 cases for Campylobacter, 32 cases for Salmonella, and 15 cases for V. parahaemolyticus. Simulated results indicate a significant difference between our estimated incidence and the reported cases of food poisoning in this region. An enhanced surveillance system is needed to complement the present passive surveillance on foodborne illnesses in Japan to identify food safety issues more precisely, and to monitor the effectiveness of risk management options.

Quantitative modeling for risk assessment of Vibrio parahaemolyticus in bloody clams in southern Thailand.

A risk assessment of Vibrio parahaemolyticus in bloody clams (Anadara granosa) consumed in southern Thailand was conducted. This study estimated the prevalence and concentration of pathogenic V. parahaemolyticus in bloody clams at harvest and retail stages; and during this process, methods to detect the total and pathogenic V. parahaemolyticus were investigated. Consumption of bloody clams and cooking efficiency were studied using interviews and on-site observation of consumers. A beta-Poisson dose-response model was used to estimate probability of illness applying estimation methods for the most likely parameter values presented by USFDA. Microbial and behavioral data were analyzed by developing a stochastic model and the simulation gave a mean number of times a person would get ill with V. parahaemolyticus by consuming bloody clams at 5.6 x 10(-4)/person/year. Sensitivity analysis demonstrated the fraction of people who did not boil the clams properly was the primary factor in increasing risk. This study serves as an example of how a microbiological risk assessment with limited data collection and international cooperation leads to valuable local insight.

Harmonization of international risk assessment protocol.

For over centuries developments in food production and new food safety management systems in most developed countries have been perceived by many to be efficient in the prevention of food-borne disease. Nevertheless a number of problems remain dominant, one of these being the high level of food-borne microbiological disease which seems, for some pathogens, to have increased over the last decades. The development of an interdisciplinary approach with direct interaction between surveillance and risk analysis systems is described as a potential basis for improved prevention of food-borne disease. Quantitative microbiological risk assessment is a relatively new scientific approach, able to link data from food within the entire food chain and the various data on human disease to provide a clear estimation of risk. Today food safety is one of the WHOs top eleven priorities; the Organization calls for more systematic and aggressive steps to be taken to reduce significantly the risk of microbiological food-borne diseases. Dealing with this challenge is one of the major challenges for the 21st century in regard to food safety, implying a significant re-direction of food microbiology efforts in many parts of the world.

Joint FAO/WHO/IOC activities to provide scientific advice on marine biotoxins (research report).

The Joint FAO/WHO/IOC ad hoc Expert Consultation on Biotoxins in Molluscan Bivalves performed risk assessments for a number of biotoxins present in bivalve molluscs. For performing risk assessments, the Expert Consultation categorized the biotoxins into eight distinct groups based on chemical structure. The Expert Consultation established LOAELs for the azaspiracid (AZA), okadaic acid (OA), saxitoxin (STX), and domoic acid (DA) toxin groups. The derived provisional acute RfDs for the AZA, OA, STX, and DA toxin groups were 0.04 microg/kg bw, 0.33 microg/kg bw, 0.7 microg/kg bw, and 100 microg/kg bw, respectively. For the yessotoxin (YTX) group, a NOAEL was established, based on animal studies. Applying a safety factor of 100, a provisional acute RfD of 50 microg/kg bw was suggested for the YTX group. The Expert Consultation considered that the database for cyclic imines, brevetoxins, and pectenotoxins was insufficient to establish provisional acute RfDs for these three toxin groups.

[Trends in the utilization of internet for facilitating transparent and more active stakeholder participation in the Codex process in several countries].

Codex standards have become the benchmarks against which national food safety control measures and regulations are evaluated within the legal parameters of the World Trade Organization (WTO) Agreements. For this reason, high-level representation at meetings of the Codex Alimentarius Commission, it's related committees and ad hoc intergovernmental task forces continue to be a priority for many governments. Opportunities broaden for stakeholder input towards the development of government positions for all Codex work through the national Codex website. Some countries utilize a national Codex website as an effective communication tool between the national Codex Contact Point (CCP) and stakeholders. In this regard, stockholder participation in the national Codex preparation process is insufficient in Japan. One of the reasons for this could be the lack of information on Codex and the insufficient understanding of the work of Codex among Japanese stakeholders. To overcome these problems, more active and effective utilization of the Japanese Codex webpage should be considered. In this paper, we show analyses of recent trends of the information on Codex available from national Codex websites from six countries in order to identify the needs to establish a similar Japanese Codex website and possible contents of the site. The six websites of the national CCPs analyzed are regularly updated and utilized for the means of active information interchange between national CCPs and stakeholders, for example, providing basic general information on Codex, including its purpose, structure and meeting schedule, posting Codex working documents open for comment, and the Terms of Reference, key issues under discussion, and delegation reports of the previous sessions. Consequently, stakeholders interested in the paper could submit their comments to the delegate of the country whose contact details are made available on the website. This is one of the examples of active stakeholder participation. By establishing a similar communication system in Japan between the National Codex Contact Point and stakeholders, a more active stakeholder participation in the national codex process could be achieved. The web site could be used to provide information on the issues under discussion in each Committee and summaries of the Codex working documents circulated for the comments and their potential implications in Japan.

[Outbreaks of Salmonella in infants associated with powdered infant formula].

Historically, outbreaks associated with Salmonella-contaminated milk products were recognized as early as the 1950's in the United Kingdom and Bulgaria. In the 1960's and 1970's there were also a number of outbreaks related to Salmonella in various powdered milk products. As a result, Salmonella criterion was included in the Codex Code of hygienic practice for foods for infants and children. Between 1985 and 2005 at least 6 outbreaks of salmonellosis, involving as many as 250 infants, have been associated with powdered infant formula (PIF). In 2005, in France, an outbreak affecting more than 100 infants was associated with PIF contaminated with Salmonella Agona. These reported outbreaks indicated that problems persisted. Experts from two FAO/WHO Expert Consultations, held in 2004 and 2006, concluded that intrinsic contamination of PIF with Enterobacter sakazakii and Salmonella has been a cause of infection and illness in infants, including severe disease which can lead to serious developmental sequelae and death. Most of the Salmonella outbreaks associated with PIF involved unusual Salmonella serotypes, which likely aided in the recognition of these outbreaks. In many regions of the world where Salmonella serotyping is not routinely performed, identification of geographically or temporarily diffused outbreaks could be difficult. It is therefore important to use the appropriate methodology to detect unusual strains of Salmonella that cause illnesses in infants, such as the lactose-positive strain, and to perform serotyping and/or pulsed-field gel electrophoresis (PFGE) genotyping for rapid identification of Salmonella outbreaks and to establish linkages between the illness and implicated food.

Archiving of food samples from restaurants and caterers--quantitative profiling of outbreaks of foodborne salmonellosis in Japan.

The Ministry of Health, Labor and Welfare (former MHW) of Japan issued a Directive in 1997 advising restaurants and caterers to freeze portions of both raw food and cooked dishes for at least 2 weeks. This system has been useful for determining vehicle foods at outbreaks. Enumeration of bacteria in samples of stored food provide data about pathogen concentrations in the implicated food. Data on Salmonella concentrations in vehicle foods associated with salmonellosis outbreaks were collected in Japan between 1989 and 1998. The 39 outbreaks that occurred during this period were categorized by the settings where the outbreaks took place, and epidemiological data from each outbreak were summarized. Characteristics of outbreak groups were analyzed and compared. The effect of new food-storage system on determination of bacterial concentration was evaluated. Freezing and nonfreezing conditions prior to microbial examination were compared in the dose-response relationship. Data from outbreaks in which implicated foods had been kept frozen suggested apparent correlation between the Salmonella dose ingested and the disease rate. Combined with results of epidemiological investigation, quantitative data from the ingested pathogen could provide complete dose-response data sets.