'Scarlet fever is usually a mild illness, but it is highly infectious. Therefore, look out for symptoms in your child, which include a sore throat, headache, and fever, along with a fine, pinkish or red body rash with a sandpapery feel. On darker skin, the rash can be more difficult to detect visually but will have a sandpapery feel. Contact NHS 111 or your GP if you suspect your child has scarlet fever, because early treatment of scarlet fever with antibiotics is important to reduce the risk of complications such as pneumonia or a bloodstream infection. If your child has scarlet fever, keep them at home until at least 24 hours after the start of antibiotic treatment to avoid spreading the infection to others.'
Further information can be found here