Wednesday, October 17, 2012

Food Watch

Germs that cause food poisoning

Staphylococcus aureus

-Easily passed by dirty hand sneezes

Extra Information
Also known as "golden staph" and Oro staphira, it is a facultative anaerobic Gram-positive coccal bacterium.
It is frequently found as part of the normal skin flora on the skin and nasal passages.[1] It is estimated that 20% of the human population are long-term carriers of S. aureus.[1] S. aureus is the most common species of staphylococcus to cause Staph infections. S. aureus is a successful pathogen due to a combination of bacterial immuno-evasive strategies. One of these strategies is the production of carotenoid pigment staphyloxanthin, which is responsible for the characteristic golden colour of S. aureus colonies. This pigment acts as a virulence factor, primarily by being a bacterial antioxidant which helps the microbe evade the reactive oxygen species which the host immune system uses to kill pathogens.[2][3]
S. aureus can cause a range of illnesses, from minor skin infections, such as pimples, impetigo, boils (furuncles), cellulitis folliculitis, carbuncles, scalded skin syndrome, and abscesses, to life-threatening diseases such as pneumonia, meningitis, osteomyelitis, endocarditis, toxic shock syndrome (TSS), bacteremia, and sepsis. Its incidence ranges from skin, soft tissue, respiratory, bone, joint, endovascular to wound infections. It is still one of the five most common causes of nosocomial infections and is often the cause of postsurgical wound infections. Each year, some 500,000 patients in American hospitals contract a staphylococcal infection.[4]

 


Salmonella

-Grows in animals intestine
-Loves raw meat and poultry

Extra Information
Salmonella /ˌsælməˈnɛlə/ is a genus of rod-shaped, Gram-negative, non-spore-forming, predominantly motile enterobacteria with diameters around 0.7 to 1.5 µm, lengths from 2 to 5 µm, and flagella that grade in all directions (i.e., peritrichous). They are chemoorganotrophs, obtaining their energy from oxidation and reduction reactions using organic sources, and are facultative anaerobes. Most species produce hydrogen sulfide,[1] which can readily be detected by growing them on media containing ferrous sulfate, such as TSI. Most isolates exist in two phases: a motile phase I and a nonmotile phase II. Cultures that are nonmotile upon primary culture may be switched to the motile phase using a Cragie tube.[citation needed]
Salmonella is closely related to the Escherichia genus and are found worldwide in cold- and warm-blooded animals (including humans), and in the environment. They cause illnesses such as typhoid fever, paratyphoid fever, and foodborne illness.[2]

Escherichia coli

- Lives in the intestine of humans and animals
- Loves undercookedmeat

Extra Information
Escherichia coli (play /ˌɛʃɨˈrɪkiə ˈkl/;[1] commonly abbreviated E. coli) is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms (endotherms). Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans, and are occasionally responsible for product recalls due to food contamination.[2][3] The harmless strains are part of the normal flora of the gut, and can benefit their hosts by producing vitamin K2,[4] and by preventing the establishment of pathogenic bacteria within the intestine.[5][6]
E. coli and related bacteria constitute about 0.1% of gut flora,[7] and fecal-oral transmission is the major route through which pathogenic strains of the bacterium cause disease. Cells are able to survive outside the body for a limited amount of time, which makes them ideal indicator organisms to test environmental samples for fecal contamination.[8][9] There is, however, a growing body of research that has examined environmentally persistent E. coli which can survive for extended periods of time outside of the host.[10]
The bacterium can also be grown easily and inexpensively in a laboratory setting, and has been intensively investigated for over 60 years. E. coli is the most widely studied prokaryotic model organism,[citation needed] and an important species in the fields of biotechnology and microbiology, where it has served as the host organism for the majority of work with recombinant DNA.

Clostridium Perfrigens

- Found in food served in large portions
- Also found in food left in room temperature for a period of time

Below mentions how it causes food poisoning
In the United Kingdom and United States, C. perfringens bacteria are the third most common cause of foodborne illness, with poorly prepared meat and poultry the main culprits in harboring the bacterium.[2] The clostridium perfringens enterotoxin (CPE) mediating the disease is heat-labile (inactivated at 74 °C) and can be detected in contaminated food, if not heated properly, and feces.[6] Incubation time is between six and 24 (commonly 10-12) hours after ingestion of contaminated food. Often, meat is well prepared, but too far in advance of consumption. Since C. perfringens forms spores that can withstand cooking temperatures, if let stand for long enough, germination ensues and infective bacterial colonies develop. Symptoms typically include abdominal cramping and diarrhea; vomiting and fever are unusual. The whole course usually resolves within 24 hours. Very rare, fatal cases of clostridial necrotizing enteritis (also known as pigbel) have been known to involve "Type C" strains of the organism, which produce a potently ulcerative β-toxin. This strain is most frequently encountered in Papua New Guinea.
Many cases of C. perfringens food poisoning likely remain subclinical, as antibodies to the toxin are common among the population. This has led to the conclusion that most of the population has experienced food poisoning due to C. perfringens.[2]
Despite its potential dangers, C. perfringens is used as the leavening agent in salt rising bread. The baking process is thought to reduce the bacterial contamination, precluding negative effects.[3]

Source wikipedia.com

The above mentioned bacterias can cause very severe infection and we can easily contract it if we do not have the right way to handle food and practise good personal hygeine.
In order to prevent these germs from invading our bodies, me must
-Have good personal hygeine
-Buy the food safely
(Check for expiry date and other signs that the food has gone bad .
Such as dents in meatl container etc.... )
-Store the food safely
(If the food must be storedin a refrigerated place, do not leave it at room temperature. )
-Prepare the food safely
( Refer to steps below )
-Cook safely
( Make sure that you heat it until the germs die at the right temperature and do not overcook
ot there is no point of cooking the food. )
-Serving safely
(Even if you complete all the steps above correctly, there is no point if you do not serve properly at the last moment )
-Make sure that your hands are clean so that the germs do not "attack the food ".




( source of pictures : google.com )

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