Food Poisoning and Staphylococcus aureus Enterotoxins

Abstract

Staphylococcus aureus produces a wide variety of toxins including staphylococcal enterotoxins (SEs; SEA to SEE, SEG to SEI, SER to SET) with demonstrated emetic activity, and staphylococcal-like (SEl) proteins, which are not emetic in a primate model (SElL and SElQ) or have yet to be tested (SElJ, SElK, SElM to SElP, SElU, SElU2 and SElV). SEs and SEls have been traditionally subdivided into classical (SEA to SEE) and new (SEG to SElU2) types. All possess superantigenic activity and are encoded by accessory genetic elements, including plasmids, prophages, pathogenicity islands, vSa genomic islands, or by genes located next to the staphylococcal cassette chromosome (SCC) implicated in methicillin resistance. SEs are a major cause of food poisoning, which typically occurs after ingestion of different foods, particularly processed meat and dairy products, contaminated with S. aureus by improper handling and subsequent storage at elevated temperatures. Symptoms are of rapid onset and include nausea and violent vomiting, with or without diarrhea. The illness is usually self-limiting and only occasionally it is severe enough to warrant hospitalization. SEA is the most common cause of staphylococcal food poisoning worldwide, but the involvement of other classical SEs has been also demonstrated. Of the new SE/SEls, only SEH have clearly been associated with food poisoning. However, genes encoding novel SEs as well as SEls with untested emetic activity are widely represented in S. aureus, and their role in pathogenesis may be underestimated.

Characterisation of the Virulence Factors and Genetic Types of Methicillin Susceptible Staphylococcus aureus from Patients and Healthy Individuals

“…There are more than 20 different types of enterotoxins (SEA to SEE, SEG to SEI, SEIJ, SEIK-SEIQ, SER to SET, SEW, SEIU) being reported [4]. An accessory gene regulator (agr) is known to be a global regulator of staphylococcal virulon which coordinates the expression of secretion and cellassociated virulence factors [5].…”

Staphylococcus aureus Contamination during Food Preparation, Processing and Handling

“…Staphylococcus aureus is one of the major foodborne pathogens, frequently causing diseases globally as a result of food ingestion contaminated with staphylococcal toxin [1].…”

“…Microbial contamination reduces shelf life and food quality leading to food infection and poisoning outbreaks, some of which are life threatening. Continuous monitoring of food processing is essential to avoid potential health problems.Staphylococcus aureus is one of the major foodborne pathogens, frequently causing diseases globally as a result of food ingestion contaminated with staphylococcal toxin [1].S. aureus is characterized by its ability to produce enterotoxins [2], which are considered to be the main causative agents of staphylococcal food poisoning [1].…”

“…Several symptoms result from SEs ingestion, which include abdominal cramping, vomiting, diarrhea, nausea, and chills. Infected individuals usually recover from the toxicity within 24 -48 hrs [1].SEs are pyrogenic toxins of the superantigen family due to their structural relatedness and their biological activities [8]. SEs are heat-stable at higher temperatures [2].…”

Phenogenotyping of Closely Related Methicillin Resistant Staphylococcus aureus Isolated from Milk and Meat Products

“…S. aureus is involved in a wide variety of diseases in humans and animals and its pathogenicity is mainly related to a combination of toxin-mediated virulence, invasive capacity, and antibiotic resistance [26]. Some strains are able to produce enterotoxins within foodstuff, causing staphylococcal food-poisoning (SFP), and these can be divided into 5 classes: SEA, SEB, SEC, SED, and SEE), and among them SEA and B are the most common [14]. In this study, 3 of the isolates were positive for enterotoxin genes sea and seb, while 6 of the multiple antibiotic resistant isolates did not contain these most common enterotoxin genes These toxogenic isolates may be due to contamination and unhygienic handling of milk, meat and meat products in farms, slaughter houses or meat processing and manufacturing factory.…”