Clostridium perfringens: Understanding a Common Food Poisoning Culprit

Clostridium perfringens, a Gram-positive, spore-forming anaerobic bacterium, resides naturally in the intestines of both humans and animals, highlighting its potential to infiltrate food supplies. Its prevalence in these environments underscores its ability to contaminate food sources and cause foodborne illness.

Unlike many bacteria, C. perfringens exhibits remarkable resilience. It forms spores, inactive forms of the bacterium, enabling survival in adverse conditions like heat and dryness. These spores persist even during cooking, making them impervious to standard culinary precautions. Consequently, improper food storage, particularly in the temperature danger zone (between 40°F and 140°F), provides an ideal environment for these spores to transform into active bacteria and multiply within food.

Upon ingestion of contaminated food, C. perfringens can produce toxins leading to symptoms such as diarrhea. This bacterium's ability to thrive in the absence of oxygen exacerbates its potential for foodborne outbreaks, especially in settings where food handling and storage practices are suboptimal.

Recent research has also shed light on the evolving understanding of C. perfringens and its impact on public health. Advances in molecular techniques have facilitated more accurate detection and monitoring of this bacterium in food processing environments, aiding in the prevention and control of foodborne outbreaks.

In conclusion, recognizing the characteristics and resilience of C. perfringens is crucial for implementing effective food safety measures. Improved understanding and vigilance are essential to mitigate the risk of food poisoning associated with this common bacterium.
Clostridium perfringens: Understanding a Common Food Poisoning Culprit

Staphylococcal Food Poisoning History

The history of Staphylococcal food poisoning reveals a fascinating journey of scientific investigation and discovery. Vaughan and Sternberg, pioneers in the field, laid the foundation in 1884 by scrutinizing the inaugural documented case in Michigan, USA. This pivotal investigation traced the origins of Staphylococcal food poisoning back to the consumption of contaminated cheese, offering an early glimpse into the dynamics of foodborne illnesses.

A decade later, in 1894, J. Denys added a significant chapter to the narrative. His study delved into an outbreak of illness within a family, pinpointing the consumption of meat from a cow that had succumbed to vitullary fever as the culprit. Denys astutely identified the presence of pyogenic staphylococci, marking a crucial milestone in connecting specific bacterial strains to foodborne diseases.

The year 1907 saw Owen's groundbreaking work, isolating staphylococci from dried beef associated with an outbreak displaying distinct Staphylococcal food poisoning symptoms. This marked progress provided deeper insights into the modes of bacterial contamination in various food sources, contributing to the evolving understanding of food safety.

Fast forward to 1914, M. A Barber's research brought the long-sought confirmation of staphylococci's role in food poisoning. By identifying a toxin substance produced by these bacteria as the primary cause of Staphylococcal food poisoning, Barber made history. His groundbreaking findings unveiled a new paradigm, demonstrating that a toxic substance within the food itself, rather than the bacteria alone, was responsible for the illness. Barber's meticulous work included the extraction of staphylococci from contaminated milk obtained from a cow suffering from mastitis, further solidifying the link between bacterial contamination and foodborne intoxication.

In the aftermath of World War I, in 1922, Baerthlein reported a massive outbreak affecting 2000 soldiers of the German army. This event underscored the potential widespread impact of Staphylococcal food poisoning during crisis situations and emphasized the crucial role of bacteria in food safety.

The historical narrative continued with B Gail Dack's rediscovery of the role of staphylococci in food poisoning in 1929. Investigating an outbreak linked to a Christmas cake, Dack reinforced the significance of ongoing vigilance in monitoring diverse food sources for potential bacterial contamination.

Today, the collective knowledge amassed over the years has established that food poisoning caused by staphylococci is a form of foodborne intoxication. The causative agents, staphylococcal enterotoxins (SEs), serve as the focal point in understanding and preventing Staphylococcal food poisoning, showcasing the ongoing importance of historical investigations in shaping food safety protocols.
Staphylococcal Food Poisoning History

Clostridium perfringens type A food poisoning

Clostridium perfringens food poisoning is usually a mild clostridial infection. Clostridium perfringens is widely distributed in feces, soil, air, and water.

Clostridium perfringens mostly can be found on raw meat and poultry, and in the intestines of animals. Contaminated meat has caused many outbreaks. Because the spores of some strains are resistant to temperatures as high as 100°C for more than l h, their presence in foods may be unavoidable.

Once inside the gastrointestinal tract, Clostridium perfringens produces an enterotoxin that acts on the small bowel. Clostridium perfringens types A, C, and D produce an enterotoxin that is implicated in the pathogenesis of disease caused by this organism.

Only Clostridium perfringens type A has been definitively linked to this food poisoning syndrome. Clostridium perfringens type A is a significant cause of foodborne illness in Western countries because of its spore-forming ability, rapid growth, and ability to produce an enterotoxin.

Clostridium perfringens type A strains producing alpha-toxin encoded by the cpa gene, also known as phospholipase C, encoded by the plc gene, that concomitantly produce the Clostridium perfringens enterotoxin (CPE).

Production and release of CPE in the gastrointestinal tract causes diarrhea and has been associated with spore formation and lysis of the mother cell in the gut.

Illness typically occurs 8-15 h after ingestion of the contaminated food. The symptoms, which include intense abdominal cramps, gas, and diarrhea (nausea and vomiting are rare), have been attributed to a protein enterotoxin produced during sporulation of the organism in the intestine.
Clostridium perfringens type A food poisoning

Staphylococcal food poisoning

Staphylococcal food poisoning is one of the most common food-borne diseases and caused by the ingestion of food containing preformed toxins (staphylococcal enterotoxins [SEs]) produced mainly by enterotoxigenic Staphylococcus aureus.

Staphylococcus aureus is a common bacterium found on the skin and in the nasal passages of up to 25% of healthy people and animals. Staphylococcus aureus is important because it has the ability to make seven different toxins that are frequently responsible for food poisoning.

Staphylococcal enterotoxins belong to the group of enterotoxins and act in the gastrointestinal tract. They possess super-antigen character and can therefore unspecific ally activate T-cells.

The first description of food-borne disease involving staphylococci was investigated in Michigan (USA) in 1884 by Vaughan and Sternberg. This food poisoning event was because of consumption of a cheese contaminated by staphylococci.

The presence of staphylococcal enterotoxin in food is usually due to cross contamination of ready to eat food with either raw food or, most likely, contamination from a food handler that is carrying Staphylococcus aureus.

In the UK or the United States, meat or meat-based products are the food vehicles mostly involved in staphylococcal food poisoning, although poultry, salads and cream-filled bakery items are other good examples of foods that have been involved.

As clinical symptoms are often self-limiting, only 10% of staphylococcal food poisoning patients are admitted to a hospital or consult physician.

Patients typically experience several of the following symptoms include: vomiting, nausea, diarrhea, usually watery but sometimes with blood, cramps, other symptoms may include mild fever, weakness, dizziness and chills. Symptoms start 30 min to 6 hours after ingestion of staphylococcal enterotoxins and go away in 1 to 2 days.

Toxin-producing Staphylococcus aureus can be identified in stool or vomit, and toxin can be detected in food items. Diagnosis of staphylococcal food poisoning in an individual is generally based only on the signs and symptoms of the patient.
Staphylococcal food poisoning

Clostridium perfringens enterotoxin

Clostridia produce the highest number of toxins of any type of bacteria. Among Clostridium species, Clostridium perfringens is the largest toxin producer and also the most widespread, being found as part of the microbiota of animals and humans and in the soil.

Clostridium perfringens type A is a spore forming, toxin producing bacterium first described by the American bacteriologist, Welch. This bacterium is a gram-positive anaerobic bacillus that is classified into five types based on the production of four major toxins (alpha, beta, epsilon, and iota). In addition to the major toxins, it can produce more than 15 other known toxins. Some C. perfringens strains produce another important toxin named Clostridium perfringens enterotoxin (CPE).

C. perfringens is a preeminent pathogen of humans and livestock, causing both histotoxic diseases and illnesses originating in the intestines, namely enteritis or enterotoxemia (where toxins produced in the intestine are absorbed into the circulation and then damage organs such as the brain).

CPE production, which is responsible for the diarrhea symptoms of diseases caused by cpe-positive type A strains, is sporulation-associated. Intact cpe genes can also be found in some type C, D and E strains.

The enterotoxin gene (CPE) is located on either the chromosome (for most C. perfringens type A food poisoning strains) or large conjugative plasmids (for the remaining type A food poisoning and most, if not all, other CPE-producing strains).

C. perfringens type A cannot only be found in soil, but also isolated from water, dust, sediments and raw and processed food commodities.

Meat and meat products such as soups and stews, are the most common vehicles of C. perfringens type A food poisoning, Contamination of meat by the intestinal contents of slaughtered animals may serve as an important source of this pathogen to food supply.
Clostridium perfringens enterotoxin

Gram-positive anaerobic bacillus of Clostridium perfringens

Clostridia produce the highest number of toxins of any type of bacteria. Among Clostridium species, Clostridium perfringens is the largest toxin producer and also the most widespread, being found as part of the microbiota of animals and humans and in the soil.

Clostridium perfringens is an important anaerobic pathogen causing food-borne gastrointestinal (GI) diseases in humans and animals, often referred to as perfringens food poisoning. Humans become infected by transmission of the bacteria from cooked dishes, especially meat dishes. Contamination of the meat by the intestinal contents of slaughtered animals might serve as an important source of this pathogen to the food supply.

C. perfringens develops easily in complex peptone media but much less in defined media. Under optimal conditions it can double in 7 min.

This bacterium is a gram-positive anaerobic bacillus that is classified into five types according to the production of four major toxins: alpha (α), beta (β), epsilon (ε) and iota (ι).

In addition to the major toxins, it can produce more than 15 other known toxins. Some of these additional virulence factors, including enterotoxin, necrotic enteritis B-like toxin (NetB) and beta-2 toxin, have received more attention than others due to their role in the pathogenesis of C. perfringens-associated disease (CPAD) in humans and animals.

While outbreaks of C. perfringens are common, they do not become major headlines because the typical symptoms of the illness are mild, and deaths are extremely rare.

C. perfringens is a highly ubiquitous bacterium widely distributed in all types of environment (soil, sediments, sewage, slurry, carcasses, dust, the surfaces of plants, etc.). Healthy humans and animals can be carriers of C. perfringens in their digestive tubes.
Gram-positive anaerobic bacillus of Clostridium perfringens

Histamine poisoning

Food poisoning may result from a variety of factors, but people are concerned with food poisoning resulting from the activity of microbes on the food.

Toxic compound such as histamine, originally classified as ptomaines, result from the microbial decomposition of proteins and in some instances, decarboxylation of amino acids. Theoretically, some amino acids can give rise to a ptomaine derivative plus carbon dioxide.

Histamine poisoning results from the ingestion of foods containing high levels of histamine. This poisoning historically been referred to as scombroid poisoning because of the frequent association of the illness with the consumption of spoiled scombroid fish such as mackerel and tuna.

The poisoning has also been reported in connection with non-fish fermented foods like cheese and sauerkraut.

Histamine intoxication is a chemical intoxication and self-limited illness. Even without treatment symptoms usually subside within a few hours. However of left untreated, symptoms can persist for as long as 24 to 48 hr.

The duration of the symptoms may be a function of the dose of exposure and/or the susceptibility of the affected individual.
Histamine poisoning

Foodborne illness due to bacterial food poisoning

Foodborne illness, one of the greatest public health and food industry concerns.

In some infections, microbes produce toxins inside the infected person’s body. In food poisoning cases, the microbes produce toxins the contaminated food and when people eat the food, the toxins make them very ill.

If a person eats food containing a fairly large amount of a toxin, it is like that he or she will be ill that day.

The disease is characterized by rapid onset, severity of symptoms, but usually a short duration.

Examples include botulism due to the formation of botulinum toxin in the food from the growth of certain clostridial species, staphylococcal and histamine poisoning.

Where these toxic food poisonings result from bacterial toxins, the poisons are synthesized in the food. 

Today, staphylococcal food poisoning ranks as the second most reported of all types of foodborne disease. Because most staphylococcal outbreaks probably t unreported, staphylococcal food poisoning could actually be the most common type.

Symptoms of foodborne illness are diarrhea, nausea, abdominal pain or vomiting without fever or upper respiratory distress.

Most foodborne illnesses are caused by the mishandling of food or the faulty cooking or storage of food, either in food service establishment or at home.
Foodborne illness due to bacterial food poisoning

Streptococcus in food poisoning

Streptococcus can cause a wide variety of disease including pharyngitis, meningitis, pneumonia, endocarditis, erysipelas and necrotising fascilitis.

Streptococcus may be found in the nose and throat and can cause a wide range of infections in humans.

While no longer a major cause of foodborne illness, streptococcus was among the first to be recognized as pathogens transmitted by milk and prepared food stuffs. These bacteria are found sometimes in poultry too.

B-haemolytic streptococci, St. pyogenes and Ent, faecalis have been implicated in food poisoning to a significant degree, causing classical symptoms such as diarrhea, as well as being responsible for other food-borne infections such as epidemic tonsillitis.  However, foodborne infection is infrequent.

In addition, no enterotoxin or other mechanisms of enteropathogenicity have been found in streptococcal strains associated with food poisoning. Heat treatment to at least 165 °F is an adequate measure to destroy any viable Streptococci that might be present in the uncooked food.

Streptococcus received their descriptive name from the Greek words streptos, meaning twisted chain and kokkos, meaning grain or seed.
Streptococcus in food poisoning

Vomiting due to food poisoning

Diarrhea, vomiting and abdominal pain are probably the most common symptoms of food poisoning. Food poisoning is a general term referring to illness, usually, vomiting, caused by contaminated food or water.

Vomiting or emesis is the forceful expulsion of gastric and intestinal contents through the mouth. The emetic type of food poisoning is characterized by nausea excessive salivation, pallor and sweating and vomiting within 0.5 – 6 hours after consumption of contaminated foods.

Occasionally, abdominal cramps and/or diarrhea may also occur. Duration of symptoms is generally less than 24 hours.

In the vomiting process the stomach divides into two sections and a deep inspiration is taken; then with a strong contraction of the diaphragm and abdominal muscles the stomach contents are regurgitated up via the esophagus.

If vomiting occurs only an hour or so after food consumption, it may be caused by Staphylococcus aureus or Bacillus cereus toxins. These enterotoxins are absorbed in the stomach and act via the central vomiting center.

Vomiting from gastro-enteric infections, for example salmonella or typhoid, can also be classed as food poisoning.
Vomiting due to food poisoning

Food poisoning in food service and restaurant

In foodservice, cleaning is just not clean enough. Sanitizing is the goal, which means the additional treatment of equipment and utensil after basic cleaning to kill germs and bacteria.

Bacteria can be found everywhere in the air, in restaurant and all human body. Not all bacteria are bad and some even beneficial. But a small amount will cause food to spoil and can be generate food poisoning when eaten.

Staphylococcus bacteria are perhaps the most common cause of food poisoning. The bacteria by themselves are harmless. The problem arises when they are left uncontrolled to grow in food items.

Evidence suggests that the majority of the cases are caused by the consumption of foods produced by the catering or food service industry.

The catering industry is large and diverse covering a range of commercial and public outlets such as restaurants, fast food outlets, hotels, hospital and other institutional caters holiday camp and others. 

Unfortunately, food service sanitation has not been well understood for many reasons and conditions of hygiene are appalling in many catering establishments.

People are unaware of the implications of poor sanitation and unhygienic habits which may lead to food poisoning, death, loss or reputation and eventually business.

Personal hygiene is the best way to stop bacteria from contaminating and spreading into new areas.

A strong food safety program should encompass personnel practices, food handling practices, pest control, training and physical facilities.
Food poisoning in food service and restaurant

Bacterial Food Poisoning

Bacterial Food Poisoning
The following bacteria frequently cause food poisoning:

• Salmonella
• Staphylococcus aureus
• Clostridium perfringes
• Bacillus cereus
  
  The following bacteria cause food poisoning less frequently:
• Clostridium botulinum
• Some strains of Escherichia coli
  
  

All bacteria have two names. The generic name is written first and with a capital letter, e.g. Clostridium, Bacillus.

The specific name is written with a small letter after generic name, e.g. perfringes, cereus.

Bacteria with the same generic name have similar characteristics, e.g. shape, oxygen requirements, enterotoxin production and spore formation.

There are approximately 2000 species of the Salmonella genus (e.g. Salmonella typhimurium, Salmonella enteriditis, Salmonella hadar, Salmonella newport) but most of them cause food poisoning it is usual to talk about Salmonella food poisoning without distinguishing which species is actually cause.

Salmonella, Staphylococcus aureus, Clostridium perfringes and Bacillus cereus are all common cause of food poisoning in the UK and many other countries.
Bacterial Food Poisoning