Quarantine confusion

[Servalan]

DD (3 y.o.) may have had swine flu earlier in the week. She had the vast majority of the symptoms - coughing, runny nose, temperature, loss of appetite, loss of energy, feeling crap etc.

First of all, I am wondering if it really was SW, because she only had the temperature for 2 days - temperature being on and off. She only felt unwell and listless on those days, but otherwise has been fine.

She hasn't had any temperature for a couple of days and is full of beans. However, she still has a chesty cough and a snotty nose, so I'm wondering if I should still be keeping her in?

Yes. There is a good enough chance that she had it, and if she did, she would still be infectious. All it takes is for her to be at the park, and she could give it to God knows how many people.
Remember, a lot of contagion is from touch. The virus can live for twenty-four hours. She touches her nose, she touches the swing, a hand rail, the gate in. It;s there for a day, for all comers to pick up.

Just my view.