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Hepatitis and hepatocellular carcinoma in Southeast Asia.

Scientists of several countries in Southeast Asia are exchanging information on research efforts on hepatocellular carcinoma under the sponsorship of the World Health Organization. It was agreed to direct preventive measures to hepatitis B virus and aflatoxins, but research should be continued on viruses, parasites, hepatotoxins of plant organisms, food contaminants, and drugs. Preventive measures include 1) blood transfusion services, 2) other transmission controls, 3) food hygiene, and 5) the establishment of pilot projects for the study of the efficiency of control measures. International collaboration and adequate data exchange are necessary for the successful continued pursuit of knowledge in chronic liver diseases in the countries of Southeast Asia, with the goal of prevention of debilitating and fatal diseases among a large segment of the world's population.

Asia↗

Food-borne botulism. A review of 13 outbreaks.

Thirteen outbreaks of food-borne botulism occurred between 1970 and 1984. Fifty patients were affected, with 30 of them requiring hospitalization. The number of patients per outbreak ranged from one to ten (mean, 3.8). All outbreaks were caused by home-prepared foods: nine by smoked ham, one by bacon, one by sausage, and one by mussels; contaminated food was not found in one outbreak. Bacteriologic study was performed in 11 outbreaks and type B toxin, the only found, was detected in eight of them. Generalized muscular weakness, visual disturbances, extreme dry mouth, and severe constipation were observed in all inpatients. Palpebral ptosis, dysphonia, urinary retention, postural hypotension, and respiratory impairment were also reported, but not in all inpatients. Identical, but less severe, manifestations were registered in the 20 ambulatory patients. Electromyographic study showed decreased motor action potential and posttetanic facilitation. Pulmonary function, studied in four inpatients, was decreased in three. All patients recovered fully. Management consisted of supportive measures, symptomatic treatment, and nursing care. Equine antitoxin was not administered and assisted ventilation was unnecessary.

Adolescent↗

[Clinical and epidemiological aspects of enteritis due to Salmonella hadar. II. Environmental contamination by Salmonella hadar in Shizuoka Prefecture--studies on the feasibility of reducing S. hadar infection].

A systematic examination was performed for environmental food contamination by Salmonella in poultry farms, broiler chickens, broiler processing plants and meat on the market. Salmonella was isolated from 219 of 1197 samples and the serotypes showed a wide distribution. (Table 1-1). S. hadar accounted for 37.1% (96) of all isolations (259). The contamination rate of broiler chickens on arrival at broiler processing plants is relatively low. However, in the broiler processing plants, containers, processing machinery, cooling water and slaughters were highly contaminated by Salmonella, S. hadar being the most prominent serotype in the plants. 64% of chicken meat on the market was contaminated by Salmonella, S. hadar being the second most prominent serotype. 11% of the pork and none of the beef or horseflesh was contaminated by Salmonella. These results indicate that poultry is the main source of S. hadar infection in humans. However, no S. hadar was isolated from cultures of 119 samples of feed for chickens from each delivery (Table 1-1). Thus, as the main source of infection by S. hadar of broiler chickens, an association with the feed seems to be ruled out. S. hadar was isolated at three of 18 poultry farms within Shizuoka Prefecture. Follow-up studies were performed at the three poultry farms which revealed that in two of them, Salmonella was completely eradicated on completion of disinfection. In the other one farm, which is still being disinfected, various strains of Salmonella including S. hadar still survived. We conclude that the main cause of the problem is the magnification of contamination of Salmonella-free material during the process at the broiler processing plants.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Feeding behaviour of the terrestrial isopod Porcellionides pruinosus Brandt, 1833 (Crustacea, Isopoda) in response to changes in food quality and contamination.

Soil decomposition is mainly dependent on the nature and characteristics of organic matter within the soil, the environmental conditions and the activity of microorganisms and soil fauna. Isopods play an important role in decomposition through litter fragmentation and stimulating and/or ingesting fungi and bacteria. The aim of this study was to jointly evaluate the effect of different food types and the effect of heavy metal contamination of those foods through isopod feeding performance assays. These studies used the terrestrial isopod Porcellionides pruinosus. After feeding with different leaf types for the study on feeding performance, alder leaves were chosen for the contamination experiments. Feeding parameters like consumption, assimilation, egestion and growth ratios were calculated and compared among treatments and food type. Lower quality food decreased isopods performance. Exotic food types were shown to be less preferred than alder or oak leaves. Contaminated food also resulted in a decrease in performance among the feeding parameters studies, although isopods can tolerate in certain cases high amounts of heavy metals. For this reason it is possible that in future this crustacean can be used as bioindicators of soil contamination or in the evaluation of contaminated sites or remediation processes.

Alnus↗

Strategies to accelerate the applicability of gene amplification protocols for pathogen detection in meat and meat products.

Traditionally, microbiological testing of meat products has involved isolating microorganisms and performing specific biochemical, and in some cases serological, tests to confirm the presence or absence of suspected food-borne pathogens. Given the public attention meat products have received as sources of food-borne disease, there has been considerable interest in the application of rapid detection techniques that require hours rather than days for completion. Theoretically, rapid detection methods could reduce the time from the initial sampling to confirmation so that conclusive results would be available by the time to process the meat product. Both direct gene probe hybridization as well as gene amplification methods show promise as rapid detection techniques. At present, direct gene probe hybridization are being commercially utilized to confirm the presence of a suspected pathogen. A number of gene amplification protocols for detecting food-borne bacterial pathogens have been published. However, many of these studies have utilized spiked samples rather than naturally contaminated samples and many of them have involved extended template extraction/purification methodologies. There is still only a very limited amount of information on the efficacies of the various protocols in detecting bacterial pathogens, especially toxigenic Escherichia coli, Salmonella spp., Campylobacter spp., and Listeria spp., in naturally contaminated food samples. In order to develop gene amplification protocols that have relevance to the meat industry, there must be a concerted effort to utilize naturally contaminated samples in the development and evaluation of protocols, as well as to initiate multilaboratory round robin evaluations of select protocols. Availability of multilaboratory tested methodologies would provide a means to design pathogen detection strategies at the quality control level rather than an end product confirmatory response to an already documented outbreak.

Animals↗

Effects of processing on zearalenone.

Zearalenone (ZEN), a common contaminant of all major cereal grains worldwide, is produced by some plant pathogenic molds including Fusarium graminearum and F. culmorum. The biological activity of this mycotoxin is mainly attributed to its estrogenic activity that modulates/disrupts endocrine function in animals and possibly humans. Efforts have been made to reduce the level of ZEN by various chemical, physical, and biological processing methods. Some chemical treatments were shown to be effective in reducing zearalenone content in artificially or naturally contaminated foods. During physical processing, the fate of ZEN depended on its distribution in the food matrix and its chemical properties such as heat stability and solubility. For example, wet milling of contaminated corn resulted in starch that was essentially toxin-free. In contrast, animal feed fractions such as bran and germ, by-products of the wet milling process, tended to concentrate ZEN. Extrusion cooking, a complex process where food is subjected to heat, high pressures and shear stress, reduced ZEN levels in food as well as its estrogenic activity. Fermentation of foods with bacteria and yeast resulted in reduction in ZEN levels. However, fermentation can result in the conversion of ZEN to more potent derivatives such as cc-zearalenol. Further efforts are needed to identify effective methods for removing/detoxifying ZEN in foods.

Animals↗

Comparison between a cultural procedure using Rappaport-Vassiliadis broth and motility enrichments on modified semisolid Rappaport-Vassiliadis medium for Salmonella detection from food and feed.

Motility enrichment on modified semisolid Rappaport-Vassiliadis (MSRV) medium was evaluated for a rapid Salmonella detection in naturally contaminated food- and feed samples. The results of this procedure were compared with a conventional cultural procedure using Rappaport-Vassiliadis (RV) broth as selective enrichment and modified brilliant green-, xylose lysine desoxycholate- and mannitol lysine crystal violet brilliant green agar for selective plating. The productivity of motility enrichment was 87% compared to a productivity of 99% for the cultural procedure. Statistical analysis showed that there was a significant difference at the 5% level. The present study shows that a combination of direct motility enrichment with the cultural procedure could be used as a very rapid and highly cost-efficient method for Salmonella detection.

Bacteriological Techniques↗

Series of incidents of Listeria monocytogenes non-invasive febrile gastroenteritis involving ready-to-eat meats.

AIMS: A series of cases and outbreaks of febrile noninvasive gastrointestinal disease involving 31 identified cases was investigated in terms of the numbers and types of Listeria monocytogenes present in the suspect foods (ready-to-eat meats) and clinical samples from cases. METHODS AND RESULTS: Foods and faecal samples involved in the incidents were tested for the presence and number of L. monocytogenes. Isolates were typed by macrorestriction analysis using pulsed-field gel electrophoresis. The foods contained high levels of L. monocytogenes, in one case 1.8 x 10(7) g-1. Faecal samples contained L. monocytogenes for up to 15 d after the contaminated food was consumed. All isolates from the food and faecal samples were of serotype 1/2 and were indistinguishable from one another by macrorestriction typing. CONCLUSIONS: It is likely that the meats were contaminated either during their manufacture after they had been cooked or by underprocessing. The long shelf lives on these products would have allowed the contaminating L. monocytogenes to grow to the high numbers measured in this study, causing food poisoning as described. SIGNIFICANCE AND IMPACT OF THE STUDY: Outbreaks of febrile noninvasive listeriosis are relatively rare. This report adds ready-to-eat meats to the range of foods that have acted as vehicles for such outbreaks.

Bacterial Typing Techniques↗

Isolation of Arcobacter butzleri and A. cryaerophilus in samples of meats and from meat-processing plants by a culture technique and detection by PCR.

A pilot survey of sources of contamination with arcobacters (representing a potential risk for humans) was done in a wide range of samples involved various kinds of meat (beef, pork, meat products, chilled chickens, etc.) from a retail level and domestic farming. Sanitary practices in slaughterhouses and production lines were checked in two different plants (a beef and pork production and a chicken processing plant). The method is based on a selective enrichment to isolate suspect strains, in combination with a PCR technique specific for arcobacters. The choice of a suitable enrichment broth and a plating agar was made with the use of pure bacterial strains and by means of real meat samples seeded with Arcobacter butzleri. The PCR technique was optimized to allow differentiation of a 1223 bp product, typical of the genus Arcobacter, and a product of 686 bp, specific for A. butzleri a total number of 198 samples were tested, of that 33 (17%) were found to be positive for the genus Arcobacter but only 22 (11%) for A. butzleri.

Agar↗

Detection and determination of anabolic steroids in nutritional supplements.

A method is described for the determination of anabolic steroids including testosterone, 19-nor-4-androstene-3,17-dione, 4-androstene-3,17-dione and nandrolone in food supplements. Initial clean-up is done by HPLC followed by determination with GC/MS. A 'contaminated' food supplement was analysed and appeared to contain 19-nor-4-androstene-3,17-dione and 4-androstene-3,17-dione. One capsule of this nutritional supplement was ingested by five male volunteers. Urine samples were collected and analysed by GC/MS and GC/MS-MS. Neither the ratio testosterone/epitestosterone, nor the ratio androstenedione/epitestosterone increased significantly. Concentrations above 2 ng/ml for norandrosterone, the major metabolite of nandrolone, were detected until 48-144 h after ingestion of the food supplement.

Anabolic Agents↗

An outbreak of Salmonella Hadar associated with roast rabbit in a restaurant.

In August 1997, an outbreak of gastroenteritis from Salmonella Hadar phage type 2 occurred among customers of a restaurant in Rimini (Emilia-Romagna region, Italy). Twenty-nine people who had eaten food prepared in the restaurant on 2 or 3 August had symptoms of acute gastroenteritis. The infection was culture-confirmed in 24 cases and the stool specimens of four healthy people were positive for Salmonella Hadar. Twelve people had to be hospitalized and a 3-year old girl died. The case-control study identified roast rabbit as the likely vehicle of infection (OR: 6.00; CI 95%: 1.65-22.83). The microbiological investigation carried out on food taken from the restaurant confirmed high levels of Salmonella Hadar in a sample of roast rabbit. Since the rabbit was well cooked, the food contamination likely occurred after cooking. Poor hygienic conditions found in the restaurant, together with inappropriate food-handling practices and inadequate storage temperatures may have contributed to spread to other foods and the severity of the outbreak.

Adolescent↗

[Epidemiological characteristics of salmonellosis in Vojvodina].

INTRODUCTION: Salmonella infections are the most common food-born diseases transmitted from animals to humans. Epidemics of salmonellosis occur after eating improperly cooked contaminated foods. MATERIAL AND METHODS: A descriptive epidemiological method was used to analyse epidemiological characteristics of salmonellosis in Vojvodina in the period 1978-2003. RESULTS: During this period there were 26,851 cases of salmonellosis (mean annual incidence of 51.1/100,000 and mean annual mortality of 0.9/100,000). Mean annual case fatality ratio during this period was 0.1%. The specific incidence was highest in 12-24 month-old children (251/100,000), and lowest in the oldest age group (13.9/100,000). Lethality was highest in children younger than 1 year, and persons older than 50 years (84%). The number of cases registered in food-born epidemics makes 41.7% of all registered cases. A mayority of 772 registered epidemics were small epidemics among families, relatives and friends. The great epidemics with large number of infected persons were due to an industrial bakery with 1713 ill persons and a public restaurant with 311 ill persons during the 80's. An epidemic was due to sandwiches from an industrial bakery distributed through the whole territory of Vojvodina with the highest incidence of salmonellosis in 1987 (137.7/100,000). The most common serotype was S. Enteritidis (69.7%), but 68 more serotypes were isolated. The most common cause of epidemics were eggs and egg products (76.2%). Salmonella spp. was isolated from food in small number of epidemics (less than 20%), because epidemics were discovered usually 2 or 3 days after their beginning.

Adolescent↗

Prevalence and molecular profiles of Salmonella collected at a commercial turkey processing plant.

In this study, whole carcasses were sampled at eight stages on a turkey-processing line and Salmonella prevalence was determined using enrichment techniques. Recovered Salmonella was further characterized using serotyping and the molecular profiles were determined using pulsed-field gel electrophoresis (PFGE). Prevalence data showed that contamination rates varied along the line and were greatest after defeathering and after chilling. Analysis of contamination in relation to serotypes and PFGE profiles found that on some visits the same serotype was present all along the processing line while on other days, additional serotypes were recovered that were not detected earlier on the line, suggesting that the birds harbored more than one serotype of Salmonella or there was cross-contamination occurring during processing. Overall, this study found fluctuations in Salmonella prevalence along a turkey-processing line. Following washing, Salmonella prevalence was significantly reduced, suggesting that washing is critical for Salmonella control in turkey processing and has significant application for controlling Salmonella at the postdefeathering and prechill stages where prevalence increased.

Animals↗

Effect of growth conditions on extracellular products (ECPs) of Aeromonas hydrophila.

Owing to the significant role in gastrointestinal illness of A. hydrophila, frequently detected in various raw and ready-to eat foods, its pathogenetic mechanisms are particularly studied. In this paper we report the results obtained studying in vitro the effect of O2 tension and inoculum age on the extra cellular products (ECPs) of seven strains food-borne isolated and cultured at 37 degrees. The considered factors influenced markedly bacterial growth as well as ECPs production and the more notable differences were detected among 15 hours old strains let grown slowly shaking (15SH), that showed the highest bacterial yield, and 24 h old strains cultured statically (24ST), whose haemolysin and cytotoxin production was favoured. Wilcoxon test shows as, in these latter conditions, the strains needed short time to adapt the haemolysin and cytotoxin production. The oxygen tension reduction, extending the replication time, induces the bacterial metabolism toward secondary products, as verified by Spearman test applied to ECPs indexes. The increased production per cell of virulence-associated factors could be responsible of gastrointestinal disorders caused by food-borne A. hydrophila strains, even without a massive gut colonization, especially when immunocompromised individuals ingest contaminated foods.

Aeromonas hydrophila↗