Necrotising fasciitis (NF)

The characteristics, diagnosis, management and epidemiology of necrotising fasciitis (NF).

Necrotising fasciitis (NF) is a bacterial infection that affects the soft tissue and fascia (a sheet or band of fibrous connective tissue separating or binding together muscles and organs). It can occur following a cut or some other opportunity for the bacteria to enter the body, such as surgery.

NF is a rare but serious condition and can affect anyone.

Characteristics and diagnosis

Early symptoms (usually within 24 hours) of NF include:

  • intense and severe pain which may seem out of proportion to any external signs of infection on the skin
  • a small but painful cut or scratch on the skin
  • fever and other flu-like symptoms

Advanced symptoms (usually within 3 to 4 days) include:

  • swelling of the painful area, accompanied by a rash
  • diarrhoea and vomiting
  • large dark blotches, that will turn into blisters and fill up with fluid

Critical symptoms (usually within 4 to 5 days) include:

  • severe fall in blood pressure
  • toxic shock from the poisons released by the bacteria
  • unconsciousness as the body weakens

A number of different bacteria can cause NF with group A Streptococcus (GAS) being the most common.

NF will progress rapidly and can result in death. Early diagnosis is important to make sure the appropriate treatment is administered. NF is treated with intravenous antibiotics.

Exploratory surgery may be undertaken and any affected tissue removed. Drugs that raise the blood pressure may be used and, in extreme circumstances, amputation may be necessary to stop the infection spreading.

There is no vaccine for NF.


There are no public health guidelines specific to the prevention and control of NF.

See the guidance for the management of infections caused by GAS (Streptococcus pyogenes), including NF.

For further information on NF, visit The Lee Sparks NF Foundation.


There are no ongoing surveillance programmes that capture data on NF cases caused by all organisms. Data is available for NF caused by Streptococcus pyogenes (GAS) captured as part of research studies.

See Health protection report (HPR): latest infection reports for bacteraemia reports, including annual reports on streptococcal bacteraemia.

For past reports on streptococcal bacteraemia, see the UK Government Web Archive.

Updates to this page

Published 1 April 2013

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