1.Sago haemolytic disease: towards understanding a novel food-borne toxicosis.
Shipton WA ; Greenhill AR ; Warner JM.
Papua New Guinea medical journal 2013;56(3-4):166-177
Sago haemolytic disease is a rare but sometimes fatal disease found primarily in the coastal regions of Papua New Guinea and among groups in which sago is a primary source of carbohydrate. It has been known since 1961 and fungi consistently have been suspected of being involved. Investigations carried out on stored sago and samples recovered from poisoning episodes have failed to indicate the consistent presence of mycotoxins. However, fungi (especially Aspergillus, Fusarium, Penicillium, Trichoderma) with strong haemolytic activity have been associated with sago, particularly when stored in open-weave baskets and sago-leaf-wrapped bundles. The haemolytic activity has been attributed to fatty acids (principally oleic, palmitic, linoleic) contained primarily in the fungal hyphae. It is hypothesized that when these acids are released through hyphal breakdown during digestion and are present in individuals with a low serum albumin level, free fatty acid excess occurs resulting in red cell membrane destruction and intravascular haemolysis. In extreme cases, blood transfusion is required. Methods of storage providing high levels of access to oxygen favour the development of fungi: eg, leaf-encased bundles and open-weave storage favour growth over that seen in starch stored under water, such as in earthen vessels. Ensuring storage does not exceed 3-4 weeks, encouraging anaerobic conditions of the starch and maintaining protein nutrition in communities where sago is relied upon should alleviate outbreak episodes.
Anemia, Hemolytic/*epidemiology/*microbiology
;
*Cycas
;
Dietary Carbohydrates/*poisoning
;
Food Handling
;
Foodborne Diseases/*epidemiology/*microbiology
;
Humans
;
Mycotoxicosis/*epidemiology/*microbiology
;
Papua New Guinea/epidemiology
2.Molecular typing of isolates from two dysentery outbreaks in Chengdu, through pulsed field gel electrophoresis technology.
Yan-Fang MIAO ; Wei HUANG ; Jian-Ping HUANG ; Zhen-Jun LI ; Dong JIN ; Zhi-Gang CUI ; Ai-Lan ZHAO ; Na LIANG ; Yan BAI
Chinese Journal of Epidemiology 2008;29(3):282-285
OBJECTIVEUsing pulsed field gel electrophoresis (PFGE) and polymerase chain reaction (PCR) typing to analyze strains isolated from two outbreaks caused by Shigella sonnei and to trace the source of infection.
METHODSVirulence genes ipaH and ial were detected by PCR and PFGE was used to subtype the isolates. Patterns were compared, using the software BioNumerics.
RESULTSWithin the 54 isolates, all were ipaH positive with 48 as ial positive. Strains from the Chongzhou outbreak were clustered into 4 PFGE patterns, with the predominant pattern accounted for 72% of the analyzed strains. The pattern of strains isolated from the cold pork with sauce was identical to the predominant pattern. The strains from Dayi outbreak were clustered into 8 PFGE patterns and the predominant pattern accounted for 56% of the test strains.
CONCLUSIONStrains from the two outbreaks were quite different and the 'cold pork with sauce' seemed to be the major source of infection, causing the outbreak of diarrhea in Chongzhou. The sources of infection of the Dayi outbreak might be complicated whereas PFGE showed a discriminatory and reproducible laboratory tool in the epidemiologic investigation on outbreaks of diarrhea.
Bacteriophage Typing ; China ; epidemiology ; Disease Outbreaks ; Dysentery, Bacillary ; epidemiology ; microbiology ; Electrophoresis, Gel, Pulsed-Field ; Food Microbiology ; Foodborne Diseases ; epidemiology ; microbiology ; Humans ; Shigella ; classification ; isolation & purification
3.Virulent gene prevalence of foodborne Listeria monocytogenes in China in 2005.
Yang YANG ; Ping FU ; Yun-Chang GUO ; Xiao-Yan PEI ; Xiu-Mei LIU
Chinese Journal of Preventive Medicine 2010;44(12):1097-1101
OBJECTIVETo study the virulent gene prevalence of foodborne Listeria monocytogenes (LM) isolated from China.
METHODS78 LM isolates derived from raw meat, cooked food, aquatic products and vegetables of 13 provinces and cities.LM isolates were investigated for prevalence of virulence genes (LIPI-1 (prfA, plcA, hly, mpl, actA, plcB); LIPI-2 (inlA, inlB), and iap) by PCR method.
RESULTS87.2% (68/78) of the isolates were prfA positive, 98.7% (77/78) of the isolates were plcA, actA and plcB positive, 97.4% (76/78) of the isolates were hly positive, 87.2% (68/78) of the isolates were mpl positive, 92.3% (72/78) of the isolates were inlA positive, 100% (78/78) of the isolates were inlB positive, 98.7% (77/78) of the isolates were iap positive. Among 21 virulent gene negative isolates, there was 7 isolates lack of two or more virulence genes. The rate of virulence genes deletion isolates from cooked meat was 31.3% (10/32), the rate of virulence genes deletion isolates from raw meat was 16.1% (5/31), the rate of virulence genes deletion isolates from vegetables was 36.4% (4/11) and rate of virulence genes deletion isolates from seafood was 50% (2/4). No significant difference was found (χ(2) = 3.721, P > 0.05). The virulence gene array-1 strains were dominant among these isolates.
CONCLUSIONAmong 78 LM isolates, prevalent of virulent genes were different except inlB, virulence genes of LIP-1 were deleted prevalently among isolates, virulence gene deletion patterns were diverse.
China ; epidemiology ; Food Contamination ; analysis ; Food Microbiology ; Foodborne Diseases ; epidemiology ; microbiology ; Listeria monocytogenes ; genetics ; isolation & purification ; pathogenicity ; Listeriosis ; epidemiology ; microbiology ; Virulence Factors ; genetics
4.Trends of foodborne diseases in China: lessons from laboratory-based surveillance since 2011.
Jikai LIU ; Li BAI ; Weiwei LI ; Haihong HAN ; Ping FU ; Xiaochen MA ; Zhenwang BI ; Xiaorong YANG ; Xiuli ZHANG ; Shiqi ZHEN ; Xiaoling DENG ; Xiumei LIU ; Yunchang GUO
Frontiers of Medicine 2018;12(1):48-57
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. Vibrio parahaemolyticus 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.
Bacteria
;
classification
;
isolation & purification
;
China
;
epidemiology
;
Disease Outbreaks
;
Food Microbiology
;
Foodborne Diseases
;
epidemiology
;
microbiology
;
Forecasting
;
Humans
;
Laboratories
;
Mushroom Poisoning
;
epidemiology
;
Population Surveillance
;
Public Health
5.PFGE of Shigella flexneri 4c isolates from food-poisoning outbreaks and sporadic diarrhea patients.
Wei ZHANG ; Jin-Cao PAN ; Dong-Mei MENG ; Rong YE ; Hao-Qiu WANG
Chinese Journal of Preventive Medicine 2007;41(1):50-53
OBJECTIVETo know the molecular characteristic of Shigella flexneri 4c isolates from patients in two food-poisoning outbreaks and one sporadic diarrhea case in Hangzhou, China.
METHODSS. flexneri isolates from patients in two food-poisoning outbreaks (outbreak 1 and outbreak 2, n = 13 and n = 12, respectively) and one sporadic diarrhea patient (n = 1) in Hangzhou during 2003 and 2005 were serotyped. Antibiotic resistances of these isolates were measured by the Kirby-Bauer method. Invasive plasmid antigen gene ipaH was examined by PCR. Pulse field gel electrophoresis (PFGE) was performed for molecular typing.
RESULTSIn outbreak 1, all 13 isolates were S. flexneri 4c, of them 6 isolates tested were quite different in PFGE patterns with dice coefficient from 0.78 to 0.92. In outbreak 2, 10 isolates were S. flexneri 4c and 2 isolates were S. flexneri X, however their PFGE patterns were almost identical (dice coefficient > 0.8). Compared to the two outbreaks isolates, the sporadic isolate was demonstrated with a distinct PFGE pattern (dice coefficient < 0.8). The antibiotic resistance patterns with 14 kinds of antibiotics had a little difference among the isolates from outbreak 1, outbreak 2 and sporadic diarrhea patient, but the same pattern was found among 10 isolates of S. flexneri 4c and 2 isolates of S. flexneri X from outbreak 2.
CONCLUSIONSPFGE might distinguish the isolates from these two outbreaks and the sporadic diarrhea patient. Some differences in PFGE patterns, serotypes and antibiotic resistance patterns might occur among S. flexneri 4c isolates during an outbreak.
Bacterial Typing Techniques ; methods ; Diarrhea ; epidemiology ; microbiology ; Disease Outbreaks ; Electrophoresis, Gel, Pulsed-Field ; Foodborne Diseases ; epidemiology ; microbiology ; Humans ; Microbial Sensitivity Tests ; Shigella flexneri ; classification ; drug effects ; isolation & purification
6.Epidemiological Investigation for Outbreak of Food Poisoning Caused by Bacillus cereus Among the Workers at a Local Company in 2010.
Kum Bal CHOI ; Hyun Sul LIM ; Kwan LEE ; Gyoung Yim HA ; Kwang Hyun JUNG ; Chang Kyu SOHN
Journal of Preventive Medicine and Public Health 2011;44(2):65-73
OBJECTIVES: In July 2 2010, a diarrhea outbreak occurred among the workers in a company in Gyeungju city, Korea. An epidemiological investigation was performed to clarify the cause and transmission route of the outbreak. METHODS: We conducted a questionnaire survey among 193 persons, and we examined 21 rectal swabs and 6 environmental specimens. We also delegated the Daegu Bukgu public health center to examine 3 food service employees and 5 environmental specimens from the P buffet which served a buffet on June 30. The patient case was defined as a worker of L Corporation and who participated in the company meal service and who had diarrhea more than one time. We also collected the underground water filter of the company on July 23. RESULTS: The attack rate of diarrhea among the employees was 20.3%. The epidemic curve showed that a single exposure peaked on July 1. The relative risk of attendance and non-attendance by date was highest for the lunch of June 30 (35.62; 95% CI, 2.25 to 574.79). There was no specific food that was statistically regarded as the source of the outbreak. Bacillus cereus was cultured from two of the rectal swabs, two of the preserved foods and the underground water filter. We thought the exposure date was lunch of June 30 according the latency period of B. cereus. CONCLUSIONS: We concluded the route of transmission was infection of dishes, spoons and chopsticks in the lunch buffet of June 30 by the underground water. At the lunch buffet, 50 dishes, 40 spoons, and chopsticks were served as cleaned and wiped with a dishcloth. We thought the underground water contaminated the dishes, spoons, chopsticks and the dishcloth. Those contaminated materials became the cause of this outbreak.
Adult
;
Aged
;
Bacillus cereus/*isolation & purification
;
Diarrhea/etiology
;
*Disease Outbreaks
;
Female
;
Foodborne Diseases/*epidemiology/microbiology
;
Fresh Water/microbiology
;
Gram-Positive Bacterial Infections/*epidemiology/microbiology
;
Humans
;
Male
;
Middle Aged
;
Questionnaires
;
Rectum/microbiology
7.Analysis of main risk factors causing foodborne diseases in food catering business.
Yong-xiang FAN ; Xiu-mei LIU ; Yi-dan BAO
Chinese Journal of Preventive Medicine 2011;45(6):543-546
OBJECTIVETo study main risk factors that cause foodborne diseases in food catering business.
METHODSData from references and investigations conducted in food catering units were used to establish models which based on @Risk 4.5 with Monte Carlo method referring to food handling practice model (FHPM) to make risk assessment on factors of food contamination in food catering units. The Beta-Poisson models on dose-response relationship to Salmonella (developed by WHO/FAO and United States Department of Agriculture) and Vibrio parahaemolyticus (developed by US FDA) were used in this article to analyze the dose-response relationship of pathogens.
RESULTSThe average probability of food poisoning by consuming Salmonella contaminated cooked meat under refrigeration was 1.96 × 10(-4) which was 1/2800 of the food under non-refrigeration (the average probability of food poisoning was 0.35 at room temperature 25°C). The average probability by consuming 6 hours stored meat under room temperature was 0.11 which was 16 times of 2 hours storage (6.79 × 10(-3)). The average probability by consuming contaminated meat without fully cooking was 1.71 × 10(-4) which was 100 times of consuming fully cooked meat (1.88 × 10(-6)). The probability growth of food poisoning by consuming Vibrio parahaemolyticus contaminated fresh seafood was proportional with contamination level and prevalence.
CONCLUSIONThe primary contamination level, storage temperature and time, cooking process and cross contamination are important factors of catering food safety.
Disease Outbreaks ; prevention & control ; Food Handling ; methods ; Food Microbiology ; Food Services ; organization & administration ; Foodborne Diseases ; epidemiology ; prevention & control ; Models, Theoretical ; Risk Assessment ; Risk Factors ; Software
8.Epidemiological characteristics of cholera in Singapore, 1992-2007.
Chia Siong WONG ; Li Wei ANG ; Lyn JAMES ; Kee Tai GOH
Annals of the Academy of Medicine, Singapore 2010;39(7):507-506
INTRODUCTIONWe carried out an epidemiological review of cholera in Singapore to determine its trends and the factors contributing to its occurrence.
MATERIALS AND METHODSEpidemiological data of all notified cases of cholera maintained by the Communicable Diseases Division, Ministry of Health, for the period 1992 to 2007 were collated and analysed. Case-control studies were carried out in outbreaks to determine the source of infection and mode of transmission. Linear patterns in age and ethnic distribution of cholera cases were assessed using chi2 test for trend.
RESULTSThere were a total of 210 cholera cases reported between 1992 and 2007. The incidence of cholera declined from 17 cases in 1992 to 7 cases in 2007. About a quarter of the cases were imported from endemic countries in the region. Between 76% and 95% of the reported cases were local residents. Four elderly patients with comorbidities and who sought medical treatment late died, giving a case-fatality rate of 1.9%. Vibrio cholerae 01, biotype El Tor, serotype Ogawa, accounted for 83.8% of the cases. The vehicles of transmission identified in outbreaks included raw fi sh, undercooked seafood and iced drinks cross-contaminated with raw seafood.
CONCLUSIONWith the high standard of environmental hygiene and sanitation, a comprehensive epidemiological surveillance system and licensing and control of food establishments, cholera could not gain a foothold in Singapore despite it being situated in an endemic region. However, health education of the public on the importance of personal and food hygiene is of paramount importance in preventing foodborne outbreaks. Physicians should also maintain a high level of suspicion of cholera in patients presenting with severe gastroenteritis, especially those with a recent travel history to endemic countries.
Adolescent ; Child ; Child, Preschool ; Cholera ; microbiology ; mortality ; Disease Outbreaks ; statistics & numerical data ; Female ; Foodborne Diseases ; epidemiology ; prevention & control ; Humans ; Incidence ; Infant ; Infant, Newborn ; Male ; Middle Aged ; Population Surveillance ; Singapore ; epidemiology ; Vibrio cholerae O1 ; isolation & purification ; Young Adult