In most cases of food poisoning, the food is contaminated by bacteria, such as salmonella or Escherichia coli (E. coli), or a virus, such as the norovirus.
Raw foods of animal origin are the most likely to be contaminated, specifically raw or undercooked meat and poultry, raw or lightly cooked eggs, unpasteurized (raw) milk, and raw shellfish. Fruits and vegetables also may get contaminated.
In the US, norovirus is the most common cause of illness from contaminated food or water—but food isn't the only way people can get norovirus. It also spreads easily from person-to-person. Symptoms usually start within 1 or 2 days of eating the contaminated food, but may begin in as few as 12 hours.
Food poisoning is caused by eating something that has been contaminated with germs. This can happen if food: is not cooked or reheated thoroughly. is not stored correctly – for example, it's not been frozen or chilled.
There are four main types of contamination: chemical, microbial, physical, and allergenic. All food is at risk of contamination from these four types. This is why food handlers have a legal responsibility to ensure that the food they prepare is free from these contaminants and safe for the consumer.
Bacteria - By far the most common source. Viruses - These do not actually grow on food but may be carried in food. Chemicals and Metals - Food poisoning caused by chemicals is rare and is most likely to be caused through carelessness e.g.. allowing cleaning chemicals to contaminate food.
Bacteria. Salmonella, Campylobacter and enterohaemorrhagic Escherichia coli are some of the most common foodborne pathogens that affect millions of people annually, sometimes with severe and fatal outcomes.
Examples of bacteria that cause infections include Streptococcus, Staphylococcus, and E. coli. Antibiotics are the usual treatment.
Pseudomonas aeruginosa
This highly resistant, "nightmare bug" has been classified by the WHO as one of the biggest threats to human health. Thriving in wet or moist places, it's one of the hardest bacteria to eradicate.
Examples of bacterial infections include whooping cough, strep throat, ear infection and urinary tract infection (UTI).
Urinary tract infections (UTI)
UTIs are mainly caused by the bacterium Escherichia coli (E. coli) and are the most common infection in humans worldwide.
Infections with microbes—viruses, bacteria, and parasites—cause most food poisoning.
The most dangerous types of food poisoning include E. coli and botulism. Some foods are poisonous. Examples include some kinds of mushrooms and certain kinds of fish (or their organs).
Bacterial toxins are mainly divided into two types based on their source: exotoxins and endotoxins.
Salmonella illness can be serious.
Symptoms usually start 6 hours to 6 days after infection. They include diarrhea that can be bloody, fever, and stomach cramps. Most people recover within 4 to 7 days without antibiotic treatment. But some people with severe diarrhea may need to be hospitalized or take antibiotics.
Food poisoning occurs through three steps: There must be bacteria on the food. The bacteria must have the right conditions to grow – that is, warmth (temperature of between 5 °C and 60 °C – the temperature danger zone), moisture and a food source. The bacteria must have time to grow and multiply.
Some of the common bacterial diseases in humans are tuberculosis, pneumonia, typhoid, tetanus, etc. Bacteria that cause various diseases in humans are known as pathogenic bacteria.
Pseudomonas aeruginosa. Pseudomonas infection is caused by strains of bacteria found widely in the environment; the most common type causing infections in humans is called Pseudomonas aeruginosa.
Bacteria are classified into five groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes). They can exist as single cells, in pairs, chains or clusters. Bacteria are found in every habitat on Earth: soil, rock, oceans and even arctic snow.
Gram-negative bacteria cause infections including pneumonia, bloodstream infections, wound or surgical site infections, and meningitis in healthcare settings. Gram-negative bacteria are resistant to multiple drugs and are increasingly resistant to most available antibiotics.
Finally, Gram-negative bacteria are more intrinsically resistant to antibiotics - they don't absorb the toxin into their insides.