Karen needs to take Jacob to the GP as soon as possible, as it sounds as though he may have scarlet fever. Assuming he is otherwise fit and healthy, he needs to start antibiotics promptly: the usual treatment is phenoxymethylpenicillin (penicillin V) four times a day for 10 days at a dose appropriate to the child’s weight and age. 

Jacob can also have paracetamol or ibuprofen as needed for symptomatic pain relief. Other measures that will help include resting and basic hygiene steps such as washing hands frequently, avoiding sharing eating utensils and towels, and using tissues rather than handkerchiefs and discarding them quickly after use. He should also stay away from nursery or school until he has had 24 hours of antibiotic treatment in order to reduce the chance of other people developing the condition – particularly those at risk of complications, such as individuals with compromised immune systems or heart problems, and pregnant women.

Scarlet fever is a notifiable disease. This means that the GP needs to tell Public Health England if the condition is suspected.