Group A Streptococcus Infection and Scarlet Fever

Recent media attention has highlighted the fact that cases of scarlet fever, a group A streptococcal infection in children are currently higher than we would typically see at this time of year. Very sadly, a rare complication of group A infection called ʻinvasive group A strep infectionʼ has resulted in a small number of deaths in younger children.

Scarlet Fever is caused by a bacteria called group A streptococcus and is usually a mild illness. Group A strep can live in the throat or on the skin and we know that 20% of healthy children are already colonised.
When Group A strep causes infection it releases a toxin that causes a rash and fever. The primary site of infection is usually in the throat. It is highly contagious and spread by droplets of saliva or mucus, for example on toys in preschool.

The incubation period from time of exposure to development of symptoms is usually 2-6 days. It will usually start with sore throat and fever of over 38°C. It then progresses after 1-2 days to the development of a red rash which starts on the abdomen and spreads up to the neck where the skin can feel rough and sandpaper like. Scarlet Fever is usually a mild illness and is treated with a 7 day course of antibiotics although there is evidence to suggest that early use of antibiotics does not change the rate of possible rare complications of this infection.

Children are advised to be excluded from school until they have had 24 hours of antibiotics. If health professionals decide not to treat, then a throat swab may be taken to support the diagnosis.

The rare complication of this infection is that invasive group A strep (iGAS) has resulted in a small number of deaths in children under 10 years of age. Compared to the total number of cases of group A streptococcus infections this is a very small number resulting in a serious complication. There is no evidence that this is due to a new strain of bacteria. It is thought that it may be related to social mixing and high levels of circulating bacteria. There are lots of viruses currently circulating that cause sore throats, colds and coughs. These will usually resolve themselves without the need of medical intervention. Occasionally, children can develop a bacterial infection on top of the virus and this can make them more unwell.

It is important to understand you may still use your judgement in deciding if your child has a simple cold that can be safely managed at home. If there are features of an illness that are more unusual, for example worsening symptoms, breathing difficulties, altered levels of arousal, or floppiness in younger children, then early medical advice should be sought.

Useful video to watch for parents:

And a useful information leaflet: