Hi, I have 7 month old DS2 doing the same. Although he wasn't sleeping through, he was waking only once for a feed and then going straight back off. Now he is waking 2 or 3 times a night, feeding and finding it hard to settle back. Fun!
We also think teeth, plus he has had a horrid cold for a few days, and is really snorky and coughing. I have also wondered about hunger, as he is getting better at solids, plus he has a top-up bottle at night, but he has big, gulping feeds when he wakes at the moment, so I am not ready to try to cut out feeds yet, as I wondered if he was having a growth spurt (not sure if this is one of the "classic" ages for it, but never mind). Also, he is VERY loud when he cries, and I don't want him to wake DS1...
So, no advice, just sympathy - you are not alone! Presumably you've given Calpol/Bonjela etc for teeth? We are using teething powders also, which do seem to help quite a bit - but not enough to stop him waking, unfortunately. Tummy bugs can really knock them back. Have you considered asking your HV whether there is any sort of probiotic you can give her to help rebalance her gut? Maybe worth a try? [Hopeful emoticon]
Hope she's back on track soon...