Symptoms of the infection include a high temperature, pink-red rash, white or red patches on the tongue and sickness.
Her mother Emma Rees, from Ogmore-by-Sea, Vale of Glamorgan, said when her daughter became unwell she was unsure what was wrong.
Mrs Rees also has a young baby and a two-year-old at home so was worried about it spreading.
His mother Kelly-Ann McNally from St Athan, Vale of Glamorgan, said they had just returned home after playing in February's snow when she noticed something was not right.
It also closes the British Council in Russia - amid tensions over the nerve agent attack on an ex-spy.