Group A streptococcal infections: guidance and data
The characteristics, diagnosis and management of group A streptococci infections.
Group A Streptococcus (GAS; Streptococcus pyogenes) is a bacterium which can colonise the throat, skin and anogenital tract. It causes a diverse range of skin, soft tissue and respiratory tract infections, including:
- tonsillitis
- pharyngitis
- scarlet fever
- impetigo
- erysipelas
- cellulitis
- pneumonia
In rare cases, patients may go on to develop post-streptococcal complications, such as:
- rheumatic fever
- glomerulonephritis
GAS can occasionally cause infections that are extremely severe. Invasive GAS (iGAS) is an infection where the bacteria is isolated from a normally sterile body site, such as the blood. Any GAS manifestation can be associated with development of streptococcal toxic shock syndrome, although patients with necrotising fasciitis are at highest risk.
GAS is spread by close contact between individuals, through:
- respiratory droplets
- direct skin contact
It can also be transmitted environmentally, through:
- contact with contaminated objects, such as towels or bedding
- ingestion of food inoculated by a carrier
Invasive GAS (iGAS) infection and scarlet fever are both notifiable diseases: health professionals must inform local health protection teams of suspected cases. Guidelines are available for the public health management of iGAS cases in the community and healthcare settings and scarlet fever outbreaks in educational settings.
Diagnosis
GAS is usually diagnosed by microbiological culture of the affected site. Serology has specific clinical uses and can be discussed with a local infection specialist.
GAS isolates from patients with healthcare-associated infections should be stored locally for a minimum of 6 months.
Management
See risk information for close community contacts of cases of iGAS infection.
Read further guidance on prevention and control of group A streptococcal infection in acute healthcare and maternity settings in the UK. Guidance on the management of close community contacts is provided below.
Epidemiology
- Pyogenic and non-pyogenic streptococcal bacteraemia: annual data from voluntary surveillance
- Group A streptococcal infections: update on activity for the 2013 to 2014 season
- Group A streptococcal infections: activity in season 2014 to 2015
- Group A streptococcal infections: activity during the 2015 to 2016 season
- Group A streptococcal infections: activity during the 2016 to 2017 season
- Group A streptococcal infections: activity during the 2017 to 2018 season
- Group A streptococcal infections: activity during the 2018 to 2019 season
Last updated 10 July 2019 + show all updates
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Added 'Group A streptococcal infections: activity during the 2018 to 2019 season' document.
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Latest seasonal activity document inserted into the Epidemiology subgroup (2017/2018 season)
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Added report on activity during the 2014 to 2015 season under epidemiology.
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Added 'Group A streptococcal infections: activity during the 2014 to 2015 season' to the collection.
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First published.