Molecular detection of virulence genes in Campylobacter species isolated from livestock production systems in South Africa

Campylobacter species are a major cause of foodborne bacterial infections in both developed and developing countries worldwide.Campylobacter jejuni is responsible for the majority of infectio ns.This study was con ducted to identify virule nceassociated genes in Campylobacter species isolated from livestock production systems in South Africa.A total of 250 fecal samples consisting of cattle(n=50),chickens(n=50),goats(n=50),sheep(n=50)and pigs(n=50)were randomly collected from livestock in Eastern Cape and KwaZulu-Natal provinces of South Africa between April and October 2018.The samples were an a lyzed for the presence of virule nee genes in Campylobacter species using molecular PCR-based methods.It was found that 77 and 23%of Campylobacter jejuni and Campylobacter coli respectively were isolated from all the livestock samples.There were positive significant(P<0.05)correlations amongst all the virulenee genes that were investigated.Chisquare and Fisher's exact tests were implemented to test for the effect of livestock species on the presenee or absenee of virule nee gen es.The study dem on strated that most of livestock species can pote ntially cause zoonotic infecti on s and food pois oning due to the high prevale nee of Campylobacter.The high prevale nee of virule nee genes highlights the sign ifica nee of Campylobacter\r\livestock production systems in South Africa.This requires the implementation of one-health approaches to reduce the impact of foodborne and zoonotic diseases for the welfare of human and animal health.

Analysis and Evaluation of Microbial Contamination of Raw Beef in Supermarkets in Phnom Penh

The study focused on analysis and evaluation of microbial contamination of raw beef was designed to （1） determine the presence of foodborne pathogens in raw beef; （2） compare the prevalence of microbial contamination among the three supermarkets, and （3） evaluate the sanitary quality of raw beef products. Also, six kind of microorganisms including Total Plate Count, Total Coliform and Fecal Coliform, which represented sanitary quality and E. coli, S. Aureus and B. cereus, which determined the presence of foodborne pathogens, were analyzed. The procedures used to analyse experimental samples taken from three supermarket （in every one week for three weeks） in Phnom Penh were based on Merck＇s study in 2005. The results had shown that there were no significant differences in Total Plate Counts, Total Coliform and Fecal Coliform in all samples, and they were found in unacceptable numbers in the raw beef products. However, the prevalence of foodborne pathogens including E. coli, S. aureus and B. cereus were found in acceptable numbers. Furthermore, the samples taken from the second supermarket had the highest level of microbial contamination among the three supermarkets, while the samples taken from the first supermarket had the lowest level of microbial contamination. This experimental finding demonstrated the need for sanitary improvement in the beef retails markets and strict sanitary guideline and implementation of these practices could guarantee consumers＇ health by consuming raw beefs with the lowest risk of foodborne pathogens.

Trends of foodborne diseases in China： lessons from laboratory- based surveillance since 2011

Abstract Foodborne disease is one of the most important public health issues worldwide. China faces various and unprecedented challenges in all aspects of the food chain. Data from laboratory-based foodborne disease surveillance systems from 2013 to 2016, as well as different regions and ages, can be found along with differences in the patterns of pathogens detected with diverse characteristics. Vibrioparahaemolyticus has been the leading cause of infectious diarrhea in China, especially among adults in coastal regions. Salmonella has been a serious and widely distributed pathogen responsible for substantial socioeconomic burden. Shigella was mostly identified in Northwest China and the inland province （Henan） with less-developed regions among children under 5 years. Data from foodborne disease outbreak reporting system from 2011 to 2016 showed that poisonous animals and plant factors responsible for most deaths were poisonous mushrooms （54.7%） in remote districts in southwest regions. The biological hazard that caused most cases reported （42.3%） was attributed to V. parahaemolyticus, the leading cause of foodborne outbreaks. In this review, we summarize the recent monitoring approach to foodborne diseases in China and compare the results with those in developed countries.

Modeling dual-scale epidemic dynamics on complex networks with reaction diffusion processes

The frequent outbreak of severe foodborne diseases(e.g., haemolytic uraemic syndrome and Listeriosis) in 2011 warns of a potential threat that world trade could spread fatal pathogens(e.g., enterohemorrhagic Escherichia coli). The epidemic potential from trade involves both intra-proliferation and inter-diffusion. Here, we present a worldwide vegetable trade network and a stochastic computational model to simulate global trade-mediated epidemics by considering the weighted nodes and edges of the network and the dual-scale dynamics of epidemics. We address two basic issues of network structural impact in global epidemic patterns:(1) in contrast to the prediction of heterogeneous network models, the broad variability of node degree and edge weights of the vegetable trade network do not determine the threshold of global epidemics;(2) a ‘penetration effect', by which community structures do not restrict propagation at the global scale, quickly facilitates bridging the edges between communities, and leads to synchronized diffusion throughout the entire network. We have also defined an appropriate metric that combines dual-scale behavior and enables quantification of the critical role of bridging edges in disease diffusion from widespread trading. The unusual structure mechanisms of the trade network model may be useful in producing strategies for adaptive immunity and reducing international trade frictions.