File Name: sign and symptoms of e coli infection 2018 articles.zip
The shiga toxin producing Escherichia coli STEC are important and occasionally lethal foodborne pathogens. The STEC comprise many serotypes and can possess a variety of pathogenicity determinants and this complicates their detection in foods, although the O serogroup predominates. This information statement is an update providing refreshed coverage of: the clinical picture and epidemiology of STEC infections, outbreaks, control of STEC in the food industry, and testing methods.
Shiga Toxin-Producing Escherichia coli (STEC) Food Poisoning and its Prevention
Luna-Guevara, M. Arenas-Hernandez, C. Silva, M. Many raw vegetables, such as tomato, chili, onion, lettuce, arugula, spinach, and cilantro, are incorporated into fresh dishes including ready-to-eat salads and sauces. The consumption of these foods confers a high nutritional value to the human diet.
However, the number of foodborne outbreaks associated with fresh produce has been increasing, with Escherichia coli being the most common pathogen associated with them. In humans, pathogenic E. Vegetables can be contaminated with E. This bacterium is able to survive in many environmental conditions due to a variety of mechanisms, such as adhesion to surfaces and internalization in fresh products, thereby limiting the usefulness of conventional processing and chemical sanitizing methods used by the food industry.
The aim of this review is to provide a general description of the behavior and importance of pathogenic E. This information can contribute to the development of effective control measures for enhancing food safety. The consumption of fresh produce has increased notably in recent years due to multiple contributions of nutrients and functional properties [ 1 , 2 ]. A diet rich in fruit and vegetables has been shown to protect against various types of cancer and chronic illnesses, such as coronary heart disease [ 4 ].
However, at the same time, consumption of fresh produce is associated with a growing number of foodborne outbreaks due to bacterial contamination of these products [ 5 ]. Leafy greens, such as lettuce, spinach, and fresh herbs, are some of the vegetables most frequently linked to bacterial infections [ 6 ].
In , the Advisory Committee on the Microbiological Safety of Food ACMSF reported that, in the UK, there were cases of reported illness, including one death, related to the consumption of fruits and vegetables between and [ 8 ].
In the same year, Germany reported an outbreak of Shiga toxin-producing E. It should be emphasized that the effect of foodborne diseases affects not only the sick person but also has considerable economic repercussions.
On the one hand, there are costs related to the sick person, including medical care and absenteeism from work and school. On the other hand, there are the costs on society, including the decrease in worker productivity, expenses of research on the outbreak, the loss of income due to food companies closing, legal expenses for litigation related to diseases, and the expenses in public medical services [ 9 ].
It has been shown that how crops are harvested, processed, and distributed has enhanced both the supply and variety of products, which may also have increased the risk of more widespread outbreaks.
The increase in illness associated with consumption of fresh produce reflects a documented increase in food contamination [ 10 ]. Foodborne illness may be the cause of fresh produce contamination by pathogenic bacteria, viruses, and protozoa [ 11 — 14 ]. This contamination may originate from manure, soil, sewage, surface water, or wildlife [ 15 ]; it may also occur during washing, slicing, soaking, packing, and food preparation [ 3 ].
Among the bacteria associated with foodborne illnesses are Listeria monocytogenes [ 16 ], E. Survival and growth of these microorganisms depend on several factors, including the specific features of the microorganism, fruit ripeness, environmental conditions, plant development, bacterial resistance to the plant metabolic processes, plus harvest, and postharvest processes [ 21 ].
Particularly, some pathogenic microorganisms can internalize and adhere to the plant surface [ 15 ]. Unfortunately, current industrial sanitizing and washing treatments of fruits and vegetables e.
Therefore, this review considers the main E. Furthermore, some recently introduced processes, considered to prevent the contamination of raw vegetables, are also described.
The most common vegetables associated with E. The possible source of the contamination of sprouts is the seed that is used it was possible to see that there were many contaminated seed lots. In the case of leafy greens, it appears that contaminated water drag water from cattle lots or water contaminated by other sources is the most common source of contamination.
There are three types of factors that affect microbiota present in fresh products: physical, chemical, and biological. Physical factors, such as pH, temperature, and moisture, affect the growth and some metabolic activities of microbiota. Chemical factors include the availability and nutrients in vegetables that may be used by microorganisms. Finally, biological factors include the presence of competitive microbiota and bacterial-plant interactions [ 24 ].
Fresh produce may be contaminated at any point in the production chain between farm and table. It has been shown that produce contamination is high during three periods: in the field, during initial processing, and in the kitchen [ 25 ]. Table 2 lists agricultural factors organic fertilizer, irrigation water, soil, and spraying of pesticides and insecticides and postharvest practices handling, collection, washing, processing, transportation, and packaging that can cause the contamination of raw vegetables by various pathogenic microorganisms, including E.
Soil and improperly composted animal manure are considered to be the main preharvest contamination factors. Soil is a natural reservoir for a large variety of human pathogens, including pathogenic E.
This bacterium can also survive during crop storage or distribution [ 30 ]. According to Launders et al. Furthermore, in organic food production, the use of animal manure is a common practice; several reports relate this type of crop system to the presence of fecal contamination, particularly during the leafy vegetable harvest [ 32 ].
Domestic animals and wildlife also represent a potential source of pathogenic bacteria, particularly for lettuce and leafy greens at preharvest stages along the coast of California and in Yuma, AZ [ 34 ]. Berger et al. Jay-Russell et al. Insects could also be a source of plant contamination. Contaminated flies have been shown to transfer E. In addition, Lynch et al. The ecological consequences of this proximity have increased the likelihood of contamination by E.
All sample types were feces, anal and cloacal swabs, or gastrointestinal contents from individual animals, unless otherwise noted [ 35 ]. Seasons are another important environmental condition that affects the prevalence of E. For example, E. The finding of E. There are current reports on outbreaks caused by the consumption of lettuce irrigated with water contaminated with E. However, the risk associated with the use of contaminated water for irrigation depends on the irrigation system used.
There is a lower probability risk of spreading pathogens from contaminated water through drip irrigation versus overhead sprinkler systems [ 37 ]. Another study shows that well water used for irrigation may be contaminated with E. Also, karst formations occur when acidic water begins to break down bedrock surfaces, allowing surface water to enter fractures in limestone, contaminating the groundwater, which then favors the survival of E.
They can become a vehicle for contamination during preharvest due to the lack of access to latrines or handwashing stations [ 18 ]. In some cases, the presence of E. This may be due to subsequent direct contamination or by pathogen multiplication during postharvest procedures in raw vegetables.
The confirmation of E. According to Zhang et al. Water is employed in many steps, such as washing, chill tanks, sprays, and shipping ice during the postharvest process.
The washing procedure is required to remove soil and debris from vegetables and some microorganisms. In spite of this, if the water used is contaminated, washing, slicing, soaking, packaging, and preparation may be the original source of E. The use of contaminated water in hydrocoolers in which fresh products are stored may generate vegetable contamination [ 40 ].
Other sources of potential contamination with E. In addition, food contamination may occur if the vegetables are prepared with unclean implements in restaurants or home kitchens. Lynch et al. Some outbreaks have been associated with the cutting of vegetables during salad preparation.
The fresh-cut produce used in the salads has been linked to the bacterial growth. Estrada-Garcia et al. Due to the great diversity of possible sources of contamination in fresh vegetables, more studies are required to learn how to prevent and correct contamination during pre- and postharvest processing. During preharvest, some pathogens may be transferred to the environment by application of inadequately composted animal manure [ 10 ].
These conditions reduce the levels of pathogenic microorganisms, promote the decomposition of cellulose and lignin, and stabilize their composition [ 42 , 43 ].
Untreated human sewage should not be used to fertilize vegetables and crops for human consumption [ 27 ], unless it complies with the specifications for the use of biosolids according to regulation [ 44 ]. Likewise, there is a recognized need to establish GAPs Good Agricultural Practices based on produce safety standard protocols for the irrigation of fresh produce [ 47 ]. During postharvest, wash water can be a transmission vehicle for pathogens, especially when this water is reused [ 28 ].
In addition, E. This point was revealed in incidents occurring in the water supply system of Walkerton, Canada, which was contaminated with E.
In addition, the risk of reclaimed water may be reduced through treatment and disinfection systems, such as activated charcoal, reverse osmosis, membrane filtration, chlorination, ozonation, and UV irradiation; however, some systems are often expensive, particularly in developing countries [ 45 ]. Postharvest treatment of fruit and vegetables is also involved in food contamination; these treatments include handling, storage, transportation, and cleaning. Various studies reveal that food workers were frequently engaged in unsafe food handling, promoting microbial contamination of ready-to-eat foods.
This typically occurs because food handlers are asymptomatic carriers of pathogenic microorganisms or have poor personal hygiene. Measures to diminish the risk of contamination by food workers include implementing proper handwashing and improving personal hygiene [ 20 ]. The World Health Organization [ 49 ] suggests 5 basic steps to prevent contamination of food by E.
Other actions to decrease food contamination are the use of better disinfectants. Recently, studies examined different and novel disinfectants for produce disinfection, such as chlorine dioxide, ozonized water, and electrolyzed oxidizing water. However, all these methods have their own limitations, making them unsuitable for an extensive application [ 50 ]. For example, ozonized water has been approved as GRAS generally recognized as safe by the FDA Food and Drug Administration as an effective disinfectant against bacteria, fungi, protozoa, and microbial spores; however, ozone is very unstable and may be toxic, causing eye and respiratory system irritation [ 51 ].
Other alternatives are those proposed by Qi et al. According to the Food Safety Modernization Act FMSA for fresh products, food handlers should receive education on the appropriate use of sanitizing agents and on the principles of food hygiene and safety [ 52 ].
Another important measure is for managers to be well trained in microbiology, so they can properly supervise preparation of the agents. These training measures could contribute to the reduction of foodborne disease outbreaks associated with the consumption of raw vegetables. The main risk factors of contamination during transportation include following improper production practices, temperature abuse, unsanitary cargo areas, improper loading or unloading procedures, damaged packaging, shipping containers in inadequate condition, poor employee habits, and road conditions [ 55 ].
Metrics details. Extraintestinal pathogenic E. Virulence factors VF related to the pathogenicity of ExPEC are numerous and have a wide range of activities, from those related to bacteria colonization to those related to virulence, including adhesins, toxins, iron acquisition factors, lipopolysaccharides, polysaccharide capsules, and invasins, which are usually encoded on pathogenicity islands PAIs , plasmids and other mobile genetic elements. Mechanisms underlying the dynamics of ExPEC transmission and the selection of virulent clones are still poorly understood and require further research. The time shift between colonization of ExPEC and the development of infection remains problematic in the context of establishing the relation between consumption of contaminated food and the appearance of first disease symptoms.
The Centers for Disease Control and Prevention CDC queried PulseNet, the national laboratory network for foodborne disease surveillance, for additional cases and began a national investigation. A case was defined as an infection between 13 March and 22 August with 1 of the 22 identified outbreak-associated E. We conducted epidemiologic and traceback investigations to identify illness subclusters and common sources. A US Food and Drug Administration—led environmental assessment, which tested water, soil, manure, compost, and scat samples, was conducted to evaluate potential sources of STEC contamination. We identified case-patients from 37 states; were hospitalized, 28 developed hemolytic uremic syndrome, and 5 died. Twenty subclusters were identified. Product traceback from subcluster restaurants identified numerous romaine lettuce distributors and growers; all lettuce originated from the Yuma growing region.
J Food Prot 1 August ; 83 8 : — Foodborne diseases are a major cause of illness in Canada. One of the main pathogens causing cases and outbreaks of foodborne illness in Canada is Escherichia coli OH7.
Diarrheal diseases are one of the major causes of mortality among children under five years old and intestinal pathogenic Escherichia coli InPEC plays a role as one of the large causative groups of these infections worldwide. InPECs contribute significantly to the burden of intestinal diseases, which are a critical issue in low- and middle-income countries Asia, Africa and Latin America. Intestinal pathotypes such as enteropathogenic E.
Metrics details. Bacterial meningitis remains a big threat to the integrity of the central nervous system CNS , despite the advancements in antimicrobial reagents. Escherichia coli is a bacterial pathogen that can disrupt the CNS function, especially in neonates.
NCBI Bookshelf. Shiga toxin-producing Escherichia coli O H7, is an enterohemorrhagic bacterial strain that is an important food and a waterborne pathogen that causes diarrhea, hemorrhagic colitis, and hemolytic-uremic syndrome HUS in humans. Transmission is via the fecal-oral route after consumption of contaminated, undercooked liquids, foods, and by person-to-person through fecal shedding. The production of Shiga toxins is a key factor contributing to the development of a range of gastrointestinal illnesses, from watery diarrhea to hemorrhagic colitis and HUS. This activity outlines the evaluation and treatment of E.
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Mini Review ARTICLE
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