Commonly called a "flesh-eating infection", necrotising fasciitis can be caused by more than one type of bacteria. These include group A Streptococcus (group A strep), Vibrio vulnificus, Klebsiella, Clostridium, Escherichia coli, Staphylococcus aureus and Aeromonas hydrophila. Group A strep is considered the most common cause of necrotising fasciitis.
Necrotising fasciitis is a serious bacterial infection of the soft tissue and fascia (a sheath of tissue covering the muscle). Sometimes toxins and enzymes made by these bacteria destroy the tissue causing it to die, leading to tissue destruction and limb loss. Severe cases can be fatal.
Some people infected with necrotising fasciitis may complain of pain or soreness of a limb or the trunk. The skin may be warm with reddish swelling that spread rapidly. There may be ulcers, blisters, or black spots on the skin. The patient may experience fever, chills, fatigue or vomiting. The level of pain is out of proportion to the visible skin changes.
Mode of transmission
The most common way of getting necrotising fasciitis is when the bacteria enter the body through a wound in the skin, such as a cut, scrape, burn, insect bite or puncture wound. Besides, necrotising fasciitis caused by Vibrio vulnificus can also be acquired through eating raw or undercooked shellfish, particularly oysters harvested from warm water.
Necrotising fasciitis is rarely spread from person to person.
High risk groups
All persons can be affected. People who come in direct contact or handle raw seafood have a higher risk of necrotising fasciitis associated with Vibrio vulnificus infection. Persons with underlying medical conditions, such as diabetes mellitus, cancer, kidney diseases, heart diseases, chronic liver diseases, or those with impaired immune response may also be at increased risk of serious complications.
The symptoms often start within hours after an injury.
Appropriate antibiotics given promptly are needed to kill the germ. In order to stop infection from spreading, surgery, e.g. removal of dead tissue or amputation of the limb, may be required. Some patients may require intensive care.
To prevent the infection, members of the public should maintain good personal hygiene and appropriate wound care:
- Keep hands clean at all times, wash hands with liquid soap and water. If hand washing facilities are not available, or when hands are not visibly soiled, clean them with 70 - 80% alcohol-based handrub as an effective alternative.
- Cleanse the wound thoroughly and cover it properly with waterproof dressing. Prompt first aid care of even minor, non-infected wounds.
- Do not go to swimming pools or other water facilities, and natural bodies of water, e.g. oceans, if having an open wound until the wound has healed.
- Wear thick rubber gloves when handling raw shellfish or other seafood.
- For details of necrotising fasciitis caused by Vibrio vulnificus, please refer to the factsheet of Vibrio vulnificus infection.
Patients should seek medical advice promptly if they develop symptoms and signs of infection such as increasing redness, swelling and pain on the skin.