Just the other day a child - who lived with a puppy - ran squealing from Frosty as if he was scared. And she ignored him. When he noticed he wasn't being pursued and he stopped, I told him, and his mum, that running was the worst thing he could do if he was scared of a dog - because that's just what gets a normal dog to chase. But my brother and I completely failed to get his kids to understand that too. And they also lived with a dog.
I find the best thing to do when a dog grabs me - is to push. If you try to pull away the dog tends to try harder to hang on and you get shredded, but if you push, they try to spit you out and it doesn't hurt as much. My council (and our police) are pretty good on dog bites - especially if there is blood drawn on a human. They're better if you can identify the dog or owner in some way (dog tag, car rego, phone number) etc. And I've found if I scold the human enough for letting their dog attack, they don't come back to the park. It doesn't happen very often at my regular park. And I've not yet seen a dog killed by another dog (touch wood) I hope I never do.
Councils and police can't afford to be complacent about dog attacks. And neither can dog owners.