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Foodborne illness has been determined to be one of the major limitations to the advancement of world health. Bacterial pathogens among the leading causes of foodborne illness are Escherichia coli (E. coli), Campylobacter, Salmonella, and Listeria. The risk of these pathogens was investigated among gastroenteritis cases in the diverse population of the state of Qatar. Fecal samples from patients admitted to Hamad Medical Corporation (HMC) with complaints of gastroenteritis were screened for the targeted pathogens using a combination of bacterial enrichments and molecular detection. Salmonella was the most common pathogen (42.9%), followed by E. coli (35.3%), and Campylobacter (21.0%). C. jejuni was the most common species of Campylobacter (67.4%). The probability of detection of E. coli decreased with age. Meanwhile, both probabilities of detection of Campylobacter and Salmonella increased with age. Listeria monocytogenes was much less common among gastroenteritis cases compared to the other pathogens.

Cytolethal distending toxin (CDT) is a heterotrimeric AB-type genotoxin produced by several clinically important bacterial pathogens. To better understand the risk of CDT within the food supply and human gastroenteritis patients in Qatar, we investigated the frequency of the CDT gene (cdtB) among Escherichia coli (E. coli) strains recovered from food products, animal livestock, and human gastroenteritis patients. In this cross-sectional study, E. coli isolates were screened for cdtB using polymerase chain reaction (PCR). cdtB positive strains were further examined for E. coli cdtB gene types (cdt I, cdt II, cdt III, cdt IV and cdtV), serotypes O157: H7, and non-O157 Shiga toxin-producing E. coli O26, O45, O103, O111, O121, and O145. Screening for other virulent factors, stx (Shiga toxin gene) and eae (gene that encodes intimin) genes were also performed. The cdtB gene was detected in E. coli isolates sourced from all three groups; animal livestock (17%), retail foods (8%), and human gastroenteritis patients (3%). Although the incidence of cdtB gene harboring E. coli is relatively low among gastroenteritis patients, there is still a risk of infection from animal reservoirs as well as retail food products. Among the three groups, E. coli isolates from humans had the lowest occurrence of cdtB, stx, eae, and O157: H7. Furthermore, we advise implementing monitoring at the food production and preparation level.

Pathogenic Escherichia coli has been listed among the most important bacteria associated with foodborne illnesses around the world. We investigated the genetic relatedness among Shiga toxin-producing E. coli (STEC) isolated along the animal food supply chain and from humans diagnosed with gastroenteritis in Qatar.Samples were collected from different sources along the food supply chain and from patients admitted to the hospital with complaints of gastroenteritis. All samples were screened for the presence of E. coli O157:H7 and non-O157 STEC using a combination of bacterial enrichment and molecular detection techniques. A proportional sampling approach was used to select positive samples from each source for further multilocus sequence typing (MLST) analysis. Seven housekeeping genes described for STEC were amplified by polymerase chain reaction, sequenced, and analyzed by MLST. Isolates were characterized by allele composition, sequence type (ST) and assessed for epidemiologic relationship within and among different sources. Nei's genetic distance was calculated at the allele level between sample pools in each site downstream.E. coli O157:H7 occurred at a higher rate in slaughterhouse and retail samples than at the farm or in humans in our sampling. The ST171, an ST common to enterotoxigenic E. coli and atypical enteropathogenic E. coli, was the most common ST (15%) in the food supply chain. None of the genetic distances among the different sources was statistically significant.Enterohemorrhagic E. coli pathogenic strains are present along the supply chain at different levels and with varying relatedness. Clinical isolates were the most diverse, as expected, considering the polyclonal diversity in the human microbiota. The high occurrence of these food adulterants among the farm products suggests that implementation of sanitary measures at that level might reduce the risk of human exposure.

Salmonella spp. and Listeria monocytogenes are foodborne pathogens of global importance. We assessed their risks and associated factors in a highly dynamic population of animals. Animal and environmental samples were collected from dairy cattle, sheep, camel and chickens at either the farms or the abattoirs. The pathogens were detected using a combination of bacterial enrichment culture and real-time polymerase chain reaction (PCR). Data on putative risk factors were collect and analysed for their significance of association with these pathogens. Salmonella spp. were detected at higher proportions in sheep faeces and sheep carcasses in comparison to cattle faeces (odds ratio = 2.4 and 2.2, respectively). This pathogen was less common in milk or carcasses samples from cattle or chickens. Sheep and camel carcass samples were highly contaminated with Salmonella spp. Faecal samples from cattle had the most diverse serovars of Salmonella enterica including S. Newport, S. Haifa, S. Kedougou, S. Kentucky, S. Mbandaka and S. Goettingen. Exotic serovars in sheep included S. Eastbourne, S. Chester and S. Kottnus. Serovars that were shed in camel faeces included S. Newport, S. Bovismorbificans and S. Infantis. In all sampled populations, detection of Salmonella spp. was more likely during warmer months than cold months. Listeria monocytogenes was not common in the targeted populations and was detected at a rate of 2.4%, mainly from sheep carcasses. The study highlights the role of food animals as reservoirs of pathogens across boundaries since all feed are imported in that population from different parts of the world.

Objective : To assess the risk of gastroenteritis associated with bacterial foodborne pathogens and identify associated factors in a highly diverse population. Material and methods : A series of case-control studies were carried out to address the stated objective. The study population consisted of individuals who were admitted to the Hamad Medical Corporation hospitals and stool analysis indicated positive findings to Campylobacter spp., Escherichia coli, or Salmonella spp. between the period of August 2009 and December 2012. Cases were defined based on positive stool analysis to any of the previously mentioned organisms. Control group was similar to case group but negative in stool analysis to the particular pathogen under study. Association between demographic characteristics and likelihood of pathogen infection were investigated using logistic regression analysis. Results : A total of 423 individuals diagnosed with these bacterial pathogens were randomly enrolled to the study. The majority of cases were infected by E.coli . Age was significantly associated with E.coli and Salmonella spp. Conclusion: E.coli infection is common among young children. The risk of Salmonella increases with age. Campylobacter may affect any age. Further investigation of interaction between foodborne pathogen infection and environmental factors is necessary Â

Salmonella spp. and Listeria monocytogenes are foodborne pathogens of global importance. We assessed their risks and associated factors in a highly dynamic population of animals. Animal and environmental samples were collected from dairy cattle, sheep, camel and chickens at either the farms or the abattoirs. The pathogens were detected using a combination of bacterial enrichment culture and real‐time polymerase chain reaction (PCR). Data on putative risk factors were collect and analysed for their significance of association with these pathogens. Salmonella spp. were detected at higher proportions in sheep faeces and sheep carcasses in comparison to cattle faeces (odds ratio = 2.4 and 2.2, respectively). This pathogen was less common in milk or carcasses samples from cattle or chickens. Sheep and camel carcass samples were highly contaminated with Salmonella spp. Faecal samples from cattle had the most diverse serovars of Salmonella enterica including S. Newport, S. Haifa, S. Kedougou, S. Kentucky, S. Mbandaka and S. Goettingen. Exotic serovars in sheep included S. Eastbourne, S. Chester and S. Kottnus. Serovars that were shed in camel faeces included S. Newport, S. Bovismorbificans and S. Infantis. In all sampled populations, detection of Salmonella spp. was more likely during warmer months than cold months. Listeria monocytogenes was not common in the targeted populations and was detected at a rate of 2.4%, mainly from sheep carcasses. The study highlights the role of food animals as reservoirs of pathogens across boundaries since all feed are imported in that population from different parts of the world.

BACKGROUND: Campylobacter and Salmonella are two of the major foodborne pathogens that contribute to the burden of disease. The cytolethal distending toxin (CDT) has been identified as one of the virulence factors that may contribute to pathogenesis and gastroenteritis. The CDT is a trimeric subunit toxin produced by gram-negative bacteria that initiates cell-cycle arrest and causes affected cells to die by apoptosis. This study investigated the occurrence of CDT among Salmonella and Campylobacter spp. isolates recovered from animals along the food supply chain and from gastroenteritis cases in Qatar.METHODS: Samples were screened for the presence of the two pathogens using a combination of bacterial enrichment and molecular detection and positive samples were examined for the presence of CDT using a polymerase chain reaction (PCR) approach. RESULTS: C. jejuni and C. coli occurred at similar rates among non-human sources, whereas C. jejuni occurred at a higher rate compared to C. coli in human cases. Both cdtB and cdtC were detected at a higher rate among C. jejuni than C. coli recovered from human cases. Only cdtB was detected in Salmonella spp. isolates from animals and at a much lower rate.CONCLUSIONS: The presence of CDT in isolates recovered from gastroenteritis cases suggests a role in the pathogenesis of the condition. Furthermore, the detection of CDT among food animal isolates along the food supply chain highlights the potential zoonotic risk.

A study using Metarhizium brunneum Petch fungal bands designed to improve delivery of conidia to adult Asian longhorned beetles, Anoplophora glabripennis (Motschulsky), was conducted to determine how a time delay between exposure to infective conidia and pairing of male and female beetles would affect the ability to successfully transfer lethal doses of conidia to a mate. We measured conidial load at the time of mate pairing (0, 4, 24, 48 h postexposure) and assessed its effect on beetle mortality. Conidial load per beetle decreased across the four sampling times, and there was no effect of beetle sex on conidial load. At all time periods postexposure, beetles that climbed across fungal bands carried enough conidia that at least some of their indirectly exposed mates died of mycosis. For indirectly exposed beetles, mortality decreased significantly as the time delay increased from 0 to 48 h, and this was independent of beetle sex. Median survival time was only 11.5 d for females indirectly exposed immediately after their mate had been exposed, but >3 wk when there was a 48-h delay before pairing. Generally, beetles exposed directly to fungal bands died faster than their indirectly exposed mates. In contrast to the pattern seen for indirectly exposed beetles, beetles exposed directly to fungal bands showed no change in survival times with a delay between exposure and pairing. Median survival times of exposed females and males were generally similar, at 10.5-12.5 d.

Background and objectives-Foodborne illness has been determined to be one of the major limitations to the advancement of world health and with the ease of travel around the world and the increase in trade of food and animal products, the risk has been exacerbated in recent years. It has been proclaimed as one of the high priority issues in the Qatar National Food Security Master Plan. Different estimates of burden of disease consistently indicate a high cost per episode, irrespective of the country where the study is conducted. Bacterial pathogens among the leading causes of foodborne illness are E. coli, Salmonella, Campylobacter and Listeria. In an effort to understand the risk of these foodborne pathogens in the retail industry in Qatar, this study investigated the presence of these pathogens among retail products. Methods—Swabs collected from retail items were screened for the presence of different serotypes of these four foodborne pathogens using a combination of bacterial enrichment and real time polymerase chain reaction detection. Most of the samples were pre-cooked and collected from big retail stores in Doha. Specific tests were for E. coli O157:H7, the E. coli genes stx and eae, which are linked to Shiga toxin-producing E. coli (STEC), E. coli O26, O111, O121, O45, O103 and O145, Salmonella, Listeria, and Campylobacter jejuni, coli and lari. Results—E. coli O157:H7 was detected among the samples at a rate of 4.2%, E. coli genes stx (26.6%) and eae (26.3%), which are linked to Shiga toxin-producing E. coli (STEC) (16.6%), E. coli O26(5.9%), O111(3.5%), O121(1.4%), O45(20.1%), O103(2.1%) and O145(2.1%). These serogroups of E. coli non-O157 are known to be food adulterants and have zero tolerance in the US. In addition, Salmonella spp. were detected in 13.5% of the samples while Listeria monocytogenes were detected in 5.2% of the samples. Conclusions—Although the prevalence for many is low, the higher prevalence of STEC genes and STEC serotype O45 is cause for concern. Shiga toxin producing serotypes are becoming nearly as much of a concern as the more commonly known O157:H7. This demonstrates the importance of properly cooking meat products. Being exposed to foodborne pathogens can increase the risk of chronic gastroenteritis sequelae, including Inflammatory Bowel Disease.

Background and Introduction—According to the Food and Agricultural Organization that more than one-third of the population of the world is affected each year by food-borne diseases caused by chemical and biological hazards. Foodsafety has been identified as high priority in the Qatar National Food Security Master Plan. Campylobacter spp. are among the leading causes of foodborne illness and capable of triggering severe gastroenteritis with grave long-term sequelae and serious economic impact such as, Inflammatory Bowel Disease (IBD). The practice of drinking fresh camel milk, although is a tradition in Qatar, is increasing around the world because of the perceived medicinal value for health in general, diabetes, autism, and allergies. In addition to the fact that camel milk is the closest to human mother's milk, it contains high levels of antioxidants and iron. Being a fresh product it is exposed o foodborne pathogens including Campylobacter spp. Understanding the pathway by which this hazard enter the food chain and pose risk to human will help in developing risk mitigation strategies. We carried out a study to assess the potential risk of illness from the consumption of camel milk contaminated with Campylobacter spp. in Qatar and identify critical intervention points that would contribute to mitigating its associated risk. Methods—We used the quantitative risk assessment (QRA) methodology using a combination of deterministic and stochastic approaches to address the stated objectives. The QRA approach helps in identifying stages in the production system from farm-to-table that are likely to play role in mitigating or exacerbating the risk of illness associated with the consumption of contaminated camel milk with this pathogen. Data on the probability of either C. jejuni or C. coli in camel milk or in humans were obtained through repeat cross-sectional studies in these populations. Estimates of the adverse health effects were obtained using risk characterization which integrated data on hazard characterization and exposure assessment, including dose-response model. A Monte Carlo Simulation of inputs in the model was performed using @Risk software (Palisade Software, Newfield, NY, USA) and parameters were obtained using Latin Hypercube sampling. Sensitivity analyses were performed to capture the effect of uncertainty and variability of the different parameters used in the model on the predicted risk of illness. Results—Our preliminary analyses showed that the probability of illness for a healthy female from the consumption of camel milk contaminated with C. jejuni ranged from 5 x 10-3 to 24 x 10-2 depending on the amount of camel milk consumed. However, the risk for male is higher (13 x 10-3 to 30 x 10-2). The estimates of illness are three times higher for immune compromised females consumed fresh camel milk. We also evaluated the risk of illness for immune compromised males that consumed fresh camel milk and it was five-times higher in comparison to healthy men. The risk of illness due to the consumption of camel milk contaminated with either C. jejuni or C. coli could be significantly reduced for either gender by increasing the efficacy of sterilizing the milk by boiling or pasteurization.

Mycoparasitism - when one fungus parasitizes another - has been reported to affect Beauveria bassiana and mycorrhizal fungi in the field. However, mycoparasitism of any fungi in the Order Entomophthorales has never been reported before now. The majority of entomophthoralean species persist as resting spores (either zygospores or azygospores) in the environment and dormant entomophthoralean resting spores (whether formed as zygospores or azygospores) are thought to be especially well adapted for survival over long periods due to their thick double walls. Entomophthoralean resting spores can accumulate in the soil as large reservoirs of inoculum which can facilitate the onset and development of epizootics. We report parasitism of azygospores of the gypsy moth pathogen Entomophaga maimaiga caged in soil from southern Ohio by the chytrid fungus Gaertneriomyces semiglobifer. G. semiglobifer had previously been isolated from soil samples from North America, Europe and Australia or horse manure from Virginia. After isolation and identification of G. semiglobifer, azygospores of E. maimaiga exposed to zoospores of G. semiglobifer exhibited high levels of mycoparasitism and G. semiglobifer was subsequently reisolated from mycoparasitized resting spores. We discuss the importance of this finding to the epizootiology of insect diseases caused by entomophthoralean fungi.