Interpretation of Shiga toxin-producing Escherichia coli O26

　1.
Background informationRecently, according to the US Food Safety News Network, an outbreak of Shiga toxin-producing Escherichia coli O26 caused by food poisoning in Chipotle, a Mexican restaurant chain in the United States, has spread in the United States, causing 20 people to be hospitalized
.
The US Centers for Disease Control and Prevention (CDC) stated that food poisoning incidents caused by Shiga toxin-producing Escherichia coli O26 have increased significantly in the past two years, which may cause more epidemics in the future, especially the number of cases that cause hemolytic uremic syndrome.
May far exceed Shiga toxin-producing Escherichia coli O157 (original link: http://#.
Vny2gemheAJ )
.
2.
Expert interpretation(1) Shiga toxin-producing Escherichia coli is the most important new and highly pathogenic food-borne pathogen in the world
.
Shiga toxin-producing Escherichia coli (STEC for short) is a new type of highly pathogenic food-borne pathogen that carries one or two Shiga toxin genes encoded by prophage, including Escherichia O26 , And more than 150 other serotypes of Escherichia coli such as O157, O45, O103, O104, O111, O121, O145
.
The bacterium is a gram-negative bacillus with no spores and flagella
.
It can grow at 10-65°C, and the optimum growth temperature is 33-42°C.
It has strong acid resistance (pH 2.
5-3.
0) and can resist the digestion of gastric acid
.
According to incomplete statistics, 70% of the non-O157 STEC infections that occurred in the United States from 1983 to 2002 were caused by the O26, O45, O103, O121, O111 and O145 serotypes; in September 2011, the United States Department of Agriculture Food Safety The Inspection Bureau has issued a notice, emphasizing that E.
coli O26 is the most common non-O157 STEC in the United States
.
An Irish study on the distribution characteristics of non-O157 STEC in meat and dairy products found that serotype O26 is also the most important non-O157 serotype that causes human food-borne diseases
.
STEC O26 has gradually become the main pathogen causing outbreaks in the United States, Japan and some developed countries in the European Union
.
(2) Meat products are the main high-risk foods that cause food-borne STEC infections
.
Economical animals such as cattle and sheep are the natural hosts of STEC.
International studies have found that the carrying rate of STEC in cattle and sheep can be as high as 71% or more
.
The United States Department of Agriculture (USDA) and the European Union Food Safety Administration (EFSA) have also confirmed that there are high-risk pollution STECs in the farms, and they can circulate within a certain range through the environment, manure, wild animals, soil, etc.
, eventually resulting in meat products, etc.
Pollution
.
The attribution analysis of STEC outbreaks in many countries from 1982 to 2006 showed that the main cause was contamination of meat products (42.
2%), followed by dairy products (12.
2%)
.
In addition, fresh fruits and vegetables and their products may also be an important transmission medium for STEC O26
.
Statistics of 24 STEC outbreaks in the United States from 1992 to 2002 found that 67% of the epidemics were caused by beef products, of which O26 was the most pathogenic serotype
.
　　(3) International organizations and some countries and regions have attached great importance to STEC pollution in meat products
.
　　At the 32nd Session of the Codex Committee on Food Hygiene (CCFH) in 1999, governments of various countries reached a consensus on the risk management of microbial risks in food according to the "food-pathogen" combination, including "E.
coli O157 in beef"
.
The FAO/WHO Joint Expert Group on Food Microbiological Risk Assessment (JEMRA) issued a risk assessment meeting report (Enterohaemorrhagic Escherichia coli in raw beef and beef products: approaches for the provision of scientific advice) in 2011 , Provides scientific advice on how to control hemorrhagic E.
coli in raw beef and beef products
.
However, to date, CCFH has not formulated relevant scientific guidelines on how to apply the General Principles of Food Hygiene to control hemorrhagic E.
coli in beef, nor has it established a limit standard for related products
.
　　In March 2012, the USDA announced that it is mandatory that six categories of non-O157 STEC (O26, O45, O103, O121, O111 and O145) must not be detected in the first processed beef products
.
After the outbreak of STEC O104 in Germany in 2011, the European Union has also strengthened the monitoring and evaluation of STEC, and has been monitoring STEC in food and patients for 5 consecutive years
.
　　(4) China's food safety standards set strict regulations on the control of Shiga toxin-producing Escherichia coli in high-risk foods
.
　　In the "National Food Safety Standards for Food Pathogenic Bacteria Limits" (GB 29921-2013) promulgated by my country in 2013, pre-packaged "meat products (applicable only to cooked meat products of beef and ready-to-eat raw meat products)" and "ready-to-eat raw meat products" "Fruit and vegetable products (only applicable to raw fruit and vegetable products)" stipulates the E.
coli O157: H7 sampling plan and limit standards
.
In other words, based on the food-borne disease and risk monitoring data currently available in China, high-risk foods (beef products and ready-to-eat fruits and vegetables) and highly pathogenic serotypes (O157: H7) have been strictly regulated and limited, but There is no clear requirement for STEC of other serotypes
.
　　3.
Expert recommendations 　　(1) Do further work on risk monitoring and risk assessment
.
　　It can be considered to appropriately increase the intensity of special monitoring of STEC in beef and its products in relevant regions and key enterprises
.
Collect evidence of the correlation between STEC contamination in beef products in China and human infection cases, and objectively and scientifically understand the true contamination level and potential risks of STEC in food
.
In order to further carry out the risk assessment of the combination of "STEC in beef products", provide a scientific basis for the country to adjust risk management decisions in a timely manner, effectively control STEC pollution, and prevent the occurrence of STEC food-borne outbreaks
.
　　(2) Strengthen the management of food production and operation process
.
　　Meat, milk, fruit and vegetable products and other production and business units should strictly implement the relevant provisions of the Food Safety Law and the Agricultural Product Quality and Safety Law, and strictly follow the requirements of relevant microbial indicators and technical specifications in the food safety standards for raw materials, environment and processing Process control, scientifically implement the Hazard Analysis Critical Control Point System (HACCP) and Good Manufacturing Practice (GMP), etc.
, and take effective measures to reduce the possibility of cross-contamination of various products during processing and sales
.
　　(3) Consumers should pay attention to cultivating good consumption and living habits
.
　　Consumers should choose business premises with good reputation to buy pre-packaged meat, milk, fruit and vegetable products
.
Attention should be paid to improving the sanitary operation awareness of kitchen processing and avoiding cross-contamination, such as keeping the work surface clean; the kitchen utensils (cutting boards, knives, etc.
) for processing raw and cooked ingredients should be used separately, and after use, try to wash them with sterilizing detergents and store them separately ; Try to eat processed and cooked food, avoid raw meat, unwashed fruits and vegetables, and dairy products with damaged packaging or beyond the shelf life, and pay attention to washing hands before meals and logistics
.
Maintain good consumption and living habits to avoid or reduce possible infections
.
This issue Expert: 　　Xiumei　Chinese Institute of Food Science and Technology vice president, national food safety risk assessment center technology consultant, researcher
　　Shi Xianming　 Shanghai Jiaotong University Department of Food, professor, director of the China-US Joint Research Center for Food Safety
　　, Li Bai　national food safety risk assessment Center Associate Professor
　　Shi Chunlei　 Shanghai Jiaotong University Associate Professor, Department of food Science main References: 1.
USDA / FSIS.
Shiga toxin-producing Escherichia coli in certain raw beef products［J］．Federal Register, 2011, 76(182): 58157-58165.

2.
Enterohaemorrhagic Escherichia coli in raw beef and beef products: approaches for the provision of scientific adviceMicrobiological risk assessment series 18, meeting report 14 October 2011.

3.
EFSA (European Food Safety Authority), ECDC (European Centre for Disease Prevention and Control), 2011.
The European Union summary report on trends and sources of zoonoses, zoonotic agents and food-borne outbreaks in 2009.
The EFSA Journal 3(2090) , 1–378.

4.
Hugh Pennington.
Escherichia coli O157.
Lancet 2010; 376: 1428–35.

5.
USDA: Risk profile for pathogenic non-O157 shiga toxin producing Escherichia coli.
2013.

6.
Xiong Y, Wang P, Lan R, Ye C, Wang H, Ren J, Jing H, Wang Y, Zhou Z, Bai X: A novel Escherichia coli O157: H7 clone causing a major hemolytic uremic syndrome outbreak in China.
PloS one 2012, 7(4) :e36144.

7.
Gould LH, Mody RK, Ong KL, Clogher P, Cronquist AB, Garman KN, Lathrop S, Medus C, Spina NL, Webb TH: Increased Recognition of Non-O157 Shiga Toxin--Producing Escherichia coli Infections in the United States During 2000–2010: Epidemiologic Features and Comparison with E.
coli O157 Infections.
Foodborne pathogens and disease 2013, 10(5):453-460.

8.
Scallan E, Hoekstra RM, Angulo FJ, Tauxe RV, Widdowson MA, Roy SL, Jones JL, Griffin PM: Foodborne illness acquired in the United States--major pathogens.
Emerging infectious diseases 2011, 17(1).

9.
Luna-Gierke R, Griffin P, Gould L, Herman K, Bopp C, Strockbine N, Mody R: Outbreaks of non-O157 Shiga toxin-producing Escherichia coli infection: USA.
Epidemiology and infection 2014:1-11.

10.
Klein S, Tian A, Witmer J, DeWaal C: The FDA Top Ten: The Riskiest Foods Regulated by the US Food and Drug Administration.
Washington, DC: The Center for Science in the Public Interest 2009.

11.
Frank C, Werber D, Cramer JP, Askar M, Faber M, an der Heiden M, Bernard H, Fruth A, Prager R, Spode A: Epidemic profile of Shiga-toxin--producing Escherichia coli O104: H4 outbreak in Germany.
New England Journal of Medicine 2011, 365(19):1771-1780.

12.
The National Standard of the People's Republic of China "National Food Safety Standards Limits of Pathogenic Bacteria in Food" (GB 29921-2013) issued by the National Health and Family Planning Commission of the People's Republic of China 2013-12 -26 released 2014-07-01 Implementation
13.
Brooks JT, Sowers EG, Wells JG, Greene KD, Griffin PM, Hoekstra RM, Strockbine NA.
Non-O157 Shiga toxin-producing Escherichia coli infections in the United States, 1983-2002 .
J Infect Dis.
2005 Oct 15;192(8):1422-1429.

14.
Zhang WL, Bielaszewska M, Bockemühl J, Schmidt H, Scheutz F, Karch H.
Molecular analysis of H antigens reveals that human diarrheagenic Escherichia coli O26 strains that carry the eaegene belong to the H11 clonal complex.
J Clin Microbiol.
2000 Aug ;38(8):2989-2993.

15.
Tozzi AE, Caprioli A, Minelli F, Gianviti A, De Petris L, Edefonti A, Montini G, Ferretti A, De Palo T, Gaido M, Rizzoni G; Hemolytic Uremic Syndrome Study Group.
Shiga toxin-producing Escherichia coli infections associated with hemolytic uremic syndrome, Italy, 1988-2000.
Emerg Infect Dis.
2003 Jan;9(1):106-108.

16.
DebRoy C, Roberts E, Kundrat J, Davis MA, Briggs CE, Fratamico PM.
Detection of Escherichia coli serogroups O26 and O113 by PCR amplification of the wzx and wzy genes.
Appl Environ Microbiol.
2004 Mar;70(3):1830-1832. 17.
DebRoy C, Roberts E, Valadez AM, Dudley EG, Cutter CN.
Detection of Shiga toxin-producing Escherichia coli O26, O45, O103, O111, O113, O121, O145, and O157 serogroups by multiplex polymerase chain reaction of the wzx gene of the O-antigen gene cluster.
Foodborne Pathog Dis.
2011 May;8(5):651-652.