How sad, this is what myths and rumors make people think...
Pit bulls are NO DIFFERENT than any other breed of dog.
FACT: News organizations have been known to report dog attacks as being made by pit bulls even before they've heard what the breed of dog is.
You don't want to hear that it's bad owners (which can often be the root of the problem, but not always), do you want to hear that just as many yorkies, golden retrievers, collies, beagles, etc have attacked when they've been provoked, hurt, sick or for many other reasons. Such as BACK YARD BREEDERS.
If you breed a dog with an unstable or grumpy temperament, the chances of that being passed along to the offspring is likely. The beautiful breeds of dogs that our ancestors spent thousands of years perfecting are being ruined by the greed ignorant of humans.
The American Pit Bull Terrier as a breed standard RULE should never show any aggression toward humans. They are, however, known to have problems with other animals. Why? Because they are terriers. Terriers are a group of breeds that have been used for thousands of years to hunt other animals AND they were used for hundreds of years as fighting dogs. The aggression toward other animals can be controlled and these dogs can be very trustworthy with other animals if they have been socialized properly. Again, NOWHERE in the breeds history has there been human aggression associated with the breed.
There is nothing triggering pit bulls to attack humans. No more than there is anything triggering any other breed of dog. Look online. You'll read up on tones of attacks made by huskies, german shepherds, akitas, etc. They are no more dangerous than any other breed of their size.
This is a BIG if, but:
If you are attacked by [any] dog, do not run. Dogs are hardwired to chase anything that runs.
Protect your body with your arms. Your arms are where the least damage will be done.
If a dog has your arm in it's mouth, don't pull back. This will turn into a game of tug-of-war and cause more injury. I guess as you say, play dead. The dog will most likely become bored with you if you are not moving.
Avoid eye contact with dogs you are not comfortable with. Eye contact can be intimidating so some dogs and it can make them feel threatened.