Group A Strep – What you need to know


  • Group A streptococcus (GAS) is a gram positive cocci usually found in normal skin and upper respiratory tract flora [1]
  • Infections caused by GAS vary and include tonsillitis, impetigo, erysipelas, cellulitis, pneumonia. The most common manifestation of GAS infection you are likely to see working in paeds is scarlet fever.
  • Occasionally invasive GAS (iGAS) causes more severe illness such as toxic shock syndrome, necrotising pneumonia and empyema, necrotising fasciitis, and meningitis.
  • In the UK scarlet fever is a notifiable disease, meaning if you diagnose it as a clinician, you have a responsibility to notify the UK Health Security Agency (UKHSA) by filling out an online form.


  • GAS outbreaks in the UK are seasonal and usually occur between February and April. GAS and more specifically scarlet fever, tends to affect young school children.
  • GAS is transmitted through close contact with an infected person, as well as coughs, sneezes and contact with an infected open wound.
  • In the UK in 2022, since September there have been a large number of reported illnesses due to GAS, mainly affecting children under 10 years of age.
  • The latest data from the UKHSA from 12.09.22 – 11.12.122 states there have been 7750 notifications of scarlet fever which is significantly higher than in previous outbreaks,
  • iGAS infections are still relatively rare. In the same timeframe the UKHSA have reported 111 cases in children 1-4 years of age and 74 in children 5-9 years of age. This compares to 194 cases in 1-4 years olds across the whole year 2017-2018 and 117 in 5-9 year olds.
  • This season 74 deaths have been reported in all age groups in England. 16 of these were children under the age of 18, compared to 27 deaths from 2017-2018. [2]

Signs and Symptoms of GAS Infection:

  • Scarlet fever typically presents like any other upper respiratory tract infection in the initial phases of the infection:
    • Flu-like symptoms, high fever, odynophagia, lymphadenopathy
    • Odynophagia can present with a reluctance to eat and drink in young children as well as vomiting, both of which lead to dehydration
    • Lymphadenopathy can sometimes present as neck pain or perceived neck stiffness, as the child can be reluctant to turn their head if they have panful swollen lymph nodes.
    • The classic rash appears 12-48 hours after the onset of the illness. It is described as having a sandpaper-like texture and it feels rough to touch, and generally looks like blanching red and white spots which can be more pronounced in skin folds. This typically lasts for 1 week.
sandpaper rash
Image credit:
  • In the first 48 hours the tongue may have a white coating with swollen papillae protruding (“white strawberry tongue”) -> this progresses to a “red strawberry tongue” after 4-5 days as the white coating sheds.
  • Children may also have red, rosy cheeks with a pale area around the mouth
rosy cheeks

Image credit:

white tongue
Image credit:
  • The tonsils will appear erythematous and swollen with exudate present. There may also be red spots / petechiae to the roof of the mouth.
  • Once the rash has disappeared children may have desquamation of the digits (peeling of the skin). **If this is seen in combination with a strawberry tongue you should be careful to examine for other signs of Kawasaki disease as the management and outcome is hugely different.**
  • Impetigo is a local infection of the superficial skin. This presents with crusting lesions which can be yellowish in colour and can occur anywhere on the body. Fever is unusual with impetigo but there may be lymphadenopathy
Creator: Helin Loik-Tomson. Image credit: CDC
  • Erysipelas is also a skin infection, but it affects deeper layers of skin and causes a tender, very erythematous skin plaque with a sharply demarcated border. It is very similar to cellulitis. This more commonly presents with fever and lymphadenopathy.
Image Credit: OA text

Signs and Symptoms of iGAS:

  • Prolonged febrile illness with high swinging temperatures. May have been preceded by symptoms of tonsillitis but developed into more serious illness
  • In the case of a severe pneumonia or empyema:
    • There will be persistent high fevers
    • Increased work of breathing or tachypnoea
    • There may or may not be a cough
    • Often, empyema’s present with abdominal pain in children and can present as an acute abdomen in severe cases.
  • In necrotising fasciitis:
    • Severe pain at site of infection with a rapidly spreading area of erythema and then necrosis
    • High fever, diarrhoea, general malaise
  • Toxic Shock syndrome can develop on from a typical scarlet fever or lower respiratory tract infection:
    • Presents as severe illness / sepsis with high fever, hypotension, confusion and quickly progresses to multi-organ failure.
    • Widespread rash similar to scarlet fever rash or can mimic sunburn
    • May be preceded by diarrhoeal / vomiting illness

Important Points for your History:

  • How long has the child been unwell for? If there has been a persistent fever for 5 days or more this changes your differentials and you will need to investigate further for PIMS-TS / Kawasaki disease or an empyema.
  • Asking about feeds / fluid intake is so important. Young children with a sore throat or who are feeling generally unwell will be reluctant to eat and drink and can become dehydrated very quickly. Ask about number of wet nappies in a day (on average a baby / toddler should have 5-8) as this is a good indicator or hydration status. Eating is not key here – as long as they are drinking plenty and passing urine then this should reassure you. (a caveat to this is you want the child to be drinking a sugary drink that will keep their blood sugar normal if they’re not eating, such as juice, or dioralyte)
  • Any unwell contacts? E.g. has there been a notice from nursery that there’s been an outbreak of tonsillitis or scarlet fever
  • Is the child immunosuppressed? – e.g. on chemotherapy / steroid / immune modulators, or has an immune deficiency. This makes them more susceptible to invasive GAS infection and you should be more cautious with these children.

On examination:

  • Does the child look sick / septic? As you get more experience in paeds this is something you can generally tell from the end of the bed. What I mean is are they happily playing or interacting, or running around the room? Or are they lethargic / irritable / miserable etc.
  • Then proceed, as always, with A-E to make sure you don’t miss anything
  • A  – is the airway patent? If they’re awake and talking to you or crying then it is. If they are unconscious with snoring or stridulous breathing call for help immediately and manage their airway as per APLS
  • B – Listen to the chest and look for increased work of breathing
  • C – Observe for tachycardia and hypotension which will occur in sepsis. Hydration status is part of examining circulation:
  • For hydration status:
    • examine the anterior fontanelle is patent – is it sunken or level?
    • Are the eyes sunken?
    • Are they tachycardic? If so – what’s the blood pressure?
    • If they’re in a nappy, is it wet? If it’s wet, is it heavy?
    • Examine for capillary refill time centrally (on the sternum) and peripherally and feel for warm peripheries. Look for mottling of the skin
    • Feel for peripheral pulse volume and character. Both weak and thready or bounding imply severe dehydration.
    • Are the mucous membranes (lips and tongue) moist or dry and cracked?
    • Lot’s of clinicians place stock in a child crying tears – do not be reassured by a child crying tears, this does not mean they are adequately hydrated and should not falsely reassure you.
  • D – If the fontanelle is patent, was it bulging? What’s the GCS? Is the child irritable or just miserable? Don’t Ever Forget Glucose! In a young child who has not been eating or drinking much they may be hypoglycaemic and this may also be why they have a reduced GCS.
  • E – Examine for lymphadenopathy, look in the ears and throat and don’t forget to inspect the tongue for signs of scarlet fever. Fully expose a young child to look for a rash and ensure no non-blanching spots. Feel the abdomen for any tenderness
  • If there is a history that may fit with Kawasaki (prolonged fever and generally unwell) examine for peripheral desquamation, induration of BCG scar, a maculopapular rash (rather than the sandpaper rash you’d see in scarlet fever), strawberry tongue, cervical lymphadenopathy, bilateral non-purulent conjunctivitis


  • If the child looks relatively well and you are suspecting scarlet fever you can just send a throat swab for MC&S (microscopy and culture) and discharge with oral antibiotics.
  • If you are concerned the child has had a prolonged illness with fever for 5 days or more, or they look acutely unwell then you should investigate for iGAS / Kawasaki disease / PIMS-TS. This should include routine bloods (FBC, U&Es, LFTs, CRP, blood culture, +/- troponin, ferritin, LDH, pro-BNP, CK, lipids, ASOT) and a chest x-ray, as well as a viral swab. (and a throat swab!)

Management of GAS:

  • If the child looks acutely unwell then call for help and manage in A-E manner.
  • If you suspect scarlet fever start Phenoxymethylpenicillin for a 10 day course as per NICE guidelines.
  • Please note the liquid preparation of Pen V is absolutely vile and has to be given QDS. It is often vomited or spat out and not taken properly. You can double the dose to give it BD or you can change to amoxicillin (although there is currently a shortage of liquid amoxicillin). You can also mix liquid antibiotics in with smoothies or yoghurts.
  • In the case where it’s not tolerated at all, or the child has a penicillin allergy you can use a macrolide such as clarithromycin
  • You also need to notify the UKHSA yourself of a suspected case of scarlet fever which you need to inform the parents you will do. Don’t let them go home before you’ve done this as you need information about schools/ nurseries etc.  
  • We are currently being told to have a low threshold to give out antibiotics for sore throats / tonsillitis etc. because of the high rate of GAS infections this season.
  • If you are concerned about the child’s oral intake you can trial a fluid challenge. You can do this by using difflam spray (benzydamine hydrochloride, which is a topical local anaesthetic) to the back of the throat and then giving dioralyte or apple juice as 5ml every 5 mins using a syringe. If they tolerate this and don’t look acutely dehydrated you can send home with safety net advice.
  • Impetigo can be managed with topical or oral antibiotics, commonly flucloxacillin (which tastes a bit nicer).
  • Erysipelas usually needs admission for a period of observation and IV antibiotics but ask a senior for their opinion if you think the child is extremely well and it looks more like a local area of cellulitis.

Safety net advice to give to parents:

  • Immediately bring to hospital via A&E if:
    • They are drinking less than 50% of normal, or not wetting nappies.
    • Reduced consciousness level
    • Bring back if fever persists beyond 5 days or if it hasn’t resolved within 2-3 days of oral antibiotics
    • If any non-blanching spots appear (parents generally know how to test for this with the glass test)
  • Advise to give regular paracetamol and ibuprofen and encourage regular drinks with some sugar in e.g. juice or dioralyte.
  • Explain that the rash may spread and will last for up to 1-2 weeks
  • Scarlet fever is highly contagious and they should inform school or nursery if you suspect this. (although public Health England also do this if you notify UKHSA)
  • It is not contagious after 1 day of oral antibiotics and they can go back to school or nursery after this if well.
  • Understandably, at the moment, parents are very anxious about GAS and if you tell them their child has scarlet fever or a GAS infection they may not want to go home. You need to reassure them if the child looks well and reiterate safety net advice. The majority of GAS infections are simple and do not progress to severe invasive infections, especially if managed appropriately with antibiotics.

Why has there been an outbreak of GAS?

  • There are varying schools of thought on this. Actually, so far, the numbers of children with GAS and iGAS have not exceeded those of previous outbreaks but numbers have been high for a such a short period of time.
  • It may be that COVID has played a part, as children were isolated for a long period of time and not exposed to all the usual childhood illnesses, and so now they’re being exposed to new strains of new illnesses and becoming more unwell as they lack immunity.
  • It may be that this year there is just a particularly virulent strain of group A strep.

The only change in your practice should be that you have a lower threshold for giving out antibiotics for suspected GAS / for admitting a child for IV antibiotics and observation if you are worried they look unwell (although this should be standard practice in paeds!)


[1]V. G. Ryan Newberger, “Streptococcus Group A,” StatPearls, 27 November 2022. [Online]. Available: [Accessed 22 December 2022].
[2]U. H. S. Agency, “UKHSA Update on Scarlet Fever and Invasive Group A Strep,” UKHSA, 2 December 2022. [Online]. Available: [Accessed 22 December 2022].

Written by Dr Rebecca Evans, paediatric ST3

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