Flesh Eating Bacteria:

Necrotizing Fasciitis
By Rachel Amato
Date: May 15, 2009


For our Wikispace project we decided to study Necrotizing fasciitis, better known as flesh-eating bacteria. While the bacterium that causes this is not actually flesh eating, it does release toxins killing the soft tissue and fascia. Many streptococcus strains are nonpathogenic, but as apparent on our webpage, this is not the case for this particular Group A Streptococcus (GAS), or other bacteria known to cause this disease including, Staphylococcus aureus, Vibrio vulnificus, Clostridium perfringens, and Bacteroides fragilis.

The bacteria that cause Necrotizing fasciitis act quickly, infecting the victim within twelve to twenty-four hours. This bacterium is also a rapid reproducer. Even in this day and age with advanced surgical procedures and early antibiotic treatment, 20-30 percent of reported cases reported to the CDC still become fatal. We also learned that 15-30 percent of us carry around streptococcus A on us with no symptoms. This does however explain why sometimes it seems infections come out of nowhere-the bacteria was already present but had not had a way in until a cut or abrasion is present. This project has taught me the importance of addressing and promptly cleaning wounds and has also helped me learn ways to recognize early forms of infections.


What is Necrotizing Fasciitis ?
This particular bacteria causes tissue death which is called necrosis, or gangrene. This occurs when the blood supply to certain areas of the body are cut off and also because toxins are released under the skin (that are oxygen depriving) into the body's soft subcutaneous tissue. In the beginning stages of the flesh eating bacteria disease this gangrene process can be scene when blackened splotches appear on the body. once this occurs the disease spreads rapidly and immediate action must be taken.

Staphylococcus aureus

Bacteria that cause this condition:

  • Group A streptococcus:
While many strains of Streptococcus are non pathogenic, this is not the case for this particular Group A Streptococcus (GAS). This streptococcus is Beta Hemolytic. According to the CDC, " GAS disease may occur when bacteria get into parts of the body where bacteria usually are not found, such as the blood, muscle, or the lungs. These infections are termed "invasive GAS disease." (CDC, 2008)
  • Staphylococcus aureus:
This bacterium can cause infections as little as minor acne and as severe as Necrotizing fasciitis. It is a facultative anerobe and gram positive coccus

  • Vibrio vulnificus: vibrio.htm
This bacteria has an alarming mortality rate of 50%. Vibrio vulnificu occurs in salt water
sources and is a moderate halophile-giving some idea where this bacteria was picked
up in victims of Necrotizing fasciitis. This bacteria is also in the same family as another
deadly bacterium, Vibrio cholerae which causes cholera. (Todar, 2008)

  • Clostridium perfringens: C.bot.jpeg
More commonly a causitive of food posoning, this bacteria is gram positive and rod-shaped. It is anaerobic,
but it is also spore forming; so the spores are actually able to endure aerobic conditions.

  • Bacteroides fragilis:
This bacterium is a gram-negative bacillus and is an obligate anerobe. Bacteroiddes fragilis is an bacteroides_fragilis.htm
opportunistic human pathogen, meaning that it does not normally cause disease, however, it can become
pathogenic in certain cases, such as in the immuno-compromised (Tortura, 2007). Bacteroiddes fragilis

bacteria has also been found resitant to many antibiotics increasing the danger of these infections.

Oftentimes post surgery patients are vulnerable to Necrotizing Fasciitis due to large areas of unhealed flesh, however seemingly minor injuries such as minor cuts or insect bites can leave an open passageway for these deadly bacteria to get in. Immune systems that are immuno-compromised such as in young children or the elderly are also more susceptible to falling ill due to these bacteria.


  • Dehydration
  • Swelling and purplish rash
  • Fever
  • Confusion, dizziness, weakness
  • Abnormally low blood pressure
  • Toxic shock
  • Severe and intense pain

Doctors and scientists have been looking into more effective treatments to fight the rapid progression of this bacteria. Catching the bacteria early and combating it with antibiotics does prove somewhat effective in minimizing damage however some forms of the bacteria have been found to be resistant to methicillan common antibiotics used to fight different types of bacteria involved are
: penicillin, clindamycin, metronidazole, carbapenem, vancomycin, penicillin, gentamicin, tobramycin, and rifampin or a combination or two or more of these depending on the level of effectiveness shown in each particular case. Those with this bacterial infection will need to immediately have an operation to remove infected tissue as this can serve as a breeding ground for the deadly bacteria to feed off of. The process of this surgery is lengthy and is tedious as it is essential all of the infection is removed properly and completely. Following a successful surgical procedure a patient will require an antibiotic regimen until infection is no longer a risk factor.


  • Take care of open wounds especially those as the result of surgery
  • The bacteria is not airborne but can be spread through bodily fluids- do not touch the wounds of others without gloves
  • Wash with soap and water frequently
  • Use products such as Neosporin on minor cuts and scrapes
  • Do not let unusual symptoms go untreated


Oftentimes patients need healing beyond the physical- this bacterium can cause major psychological problems from the trauma that occurs when this bacterium eats away at a person’s flesh or from amputation. Recently surgeons have been able to successfully complete facial reconstruction and partial face transplants.

Martin, Deborh A., et al. "Necrotizing Fasciitis with No Mortality or Limb Loss." American Surgeon (2008): 809-812.

Triesenberg, Dr. Steven. National Necrotizing Fasciitis Foundation Home Page. 30 April 2009 <http://www.nnff.org/info.html >.

P. Jarrett, M. Rademaker, M. Duffill. "The clinical spectrum of necrotising fasciitis. A review of 15 cases." Internal Medicine Journal (1997): 29-34.

Kenneth Todar, PhD. Todar's Online Textbook of Bacteriology. 2008. 6 May 2009 <http://www.textbookofbacteriology.net/V.vulnificus.html>.

Tortura, Funke and Case. Microbiology. San Francisco: Pearson, 2007. 314-320.



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The Bacteria That Can Lead to Necrotizing Fasciitis

By : Jenae Herkins
Date: May 15th 2009

Abstract: In order to understand a disease and where it comes from, we must start by finding out how the disease begins and where it comes from. In the case of Necrotizing Fasciitis, five main bacteria have become the source for the disease.The presence of some of these bacteria are on or in our body on a daily basis. These five bacteria are completely dangerous to the immunocompromised, but can be normal and nonpathogenic to a healthy person.I chose to research this bacteria because before I did this research, it seemed like fiction. The dangerous thing about this disease is that it spreads and does so quickly. This wikispace is designed to show the bacteria that can lead to this disease, preventative measures that can be taken, and what happens once necrotizing fasciitis begins its work.

Introduction: This was a topic that seemed very interesting to me. In my research not only did I see very morbid pictures of Necrotizing fasciitis, but I got a chance to learn about what makes this disease the destructor that it is. Most people only know of Necrotizing fasciitis by "Flesh eating bacteria", however this is not the right name. When a person says flesh eating bacteria, it makes it sounds as though the bacteria literally "eatting away" at the skin. This is not what happens. The bacteria release toxins, and it is this release that causes significant damage to the skin. The toxins deprive the cells of oxygen, creating the death of the cells. This death is quick and spreads. This is a disease that needs medical treatment right away. (Tortora 617).

Discussion: Research shows that there are five leading bacteria that can cause Necrotizing Fasciitis.

Streptococcus pyogenes ( Group A Streptococcus): This is a Gram-positive bacteria which is cocci and grows in long chains. It can be a small skin infection or lead to diseases such as necrotizing fasciitis.(Akiyama 193). It can appear on the skin of in the throat, a form of it is present in strep throat. These tiny cocci invade quickly and multiply rapidly. Strains of this bacteria can lead to Toxic Shock Syndrome. Although some bacteria that cause necrotizing faciitis are becoming resistant to the antibiotic Penicillum, research shows that S pyogenes is not. (Akiyama 193).

S. pyogenes bacteria @ 900x magnification.
S. pyogenes bacteria @ 900x magnification.

Staphylococcus aureus: This is a gram positive cocci that usually appear in clusters. What many people do not realize is that the are carriers for S. aureus in everyday life, they carry it on their skin. It prefers to colonize in a person's nose but can also be found in the mouth and in the intestines. This bacterium is the color yellow and is usually thick. These bacterium are facultative anaerobes (Tortora 332). S. aureus is something that we stood pay attention too because Staphylococci has many forms and many are toxic. We often hear of people getting staph infections but we never stop and think about what a staph infection really is. In it's weakest form, contact with S. aureus can lead to food poisioning. ( Lowy 222). At it's worst as we have seen, an untreated S. aureus infection can lead to Necrotizing Fasciitis. Perhaps the most dangerous thing about S. aureus however, is that it continues to evolve and the more that we as humans fight it, the stronger and more dangerous it becomes. (Tortora 332).
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Vibrio vulnificus: This is a dangerous bacteria, of those infected, 50% die. This bacteria also accounts for 95% of all seafood related deaths.
This is a Gram-negative bacteria that is motile. V vulnificus are moderate halophiles (Lancet 1421). This means that not only can they tolerate salt conditions, but they can do well in salty conditions. This is why it is responsibile for seafood related deaths because it is present in seawater, plankton, shellfish and the sediment of the water (Lancet 1422). Disease occurs once a person eats contaminated food or if a person enters seawater with an open cut or wound. Also, those who are immunocompromised are at risk for developing septicemia or skin lesions. (Lancet 1422). A study was done in order to see the effects that V vulnificus had on people who were infected. Of the 62 infected people, 4 developed Necrotizing Fasciitis. (Lancet 1423).

external image vibrio.jpg&usg=AFQjCNEIkdr7dIMKb_waoZOcvzAlFDFoJw
Clostridium prefringens: This is a Gram- positive, rod bacteria. This bacteria can produce endospores. This bacteria is completely anaerobic and is killed in the presence of oxygen. (Tortora 330). Even though the bacteria itself may die with oxygen exposure, it's spores can not only surive in the presence of oxygen but can survive for long periods of time. This bacteria is essentailly everywhere organic compounds are found, this includes dirt, water, and human bodies (especially intestines). This bacteria is also an oppurtunisitic bacteria in that it does not have an intense effect on a healthy person, at worst it may cause diarrhea. However, to a immunocompromised person, this bacteria can cause gas ganrene.(Tortura 330).This is also a huge contributor to the devastation of Necrotizing Fasciitis.

external image Clostridium_perfringens.jpg

Bacteroides fragilis: Oligate anaerobe and has over 340 strains! (Johnson 245). It is also an opppurtunistic bacteria and is currently being studied because of the evolution of the bacteria. Of the 340 strains, B. fragilis is in the top ten most common. It is also Gram-negative and is highly resistant to penicillin, which makes it even more dangerous as it continues to evolve. (Johnson 251).

external image 5_BactFragilis_6.jpg&usg=AFQjCNGpLj4qCGwI8rvcFq8y_Rjz2MrsXw

Literature Cited:

Akiyama, A. 2003. Assesment of Streptococcus pyrogenes Microcolony Formation in Infected Skin by Cofocal Laser Scanning Microscopy. Published online in Journal of Dermatological Science 359, 124 (20Clin03).

Cleve, C. 1998. Group A Streptococcal Necrotizing Fasciitis Diagnosing and Treating the "Flesh-eating syndrome". Published online in New England Journal of Medicine 38, 241-249 (1998).

Johnson, J. 2000. Bacteroides fragilis and other Saccharolytic Bacteroides. Published online in Soceity for General Microbiology 28, 245-256 (2000).

Lancet, 1999. Clinical,Epidemiological and Microbiological features of Vibrio vulnificus. Published online in Clinical Microbiology Reviews 1091, 1421-1444 (1999).

Lowy, F. 1998. Staphylococcus aureus Infections. Published online in New England Journal of Medicine 339, 520-532 (1998).

Tortora, Gerard J, Berdell R. Funke, and Christine L. Case. Microbiology An Introduction with CDROM. Boston: Benjamin-Cummings Company, 2006.