Dogs are the most diverse mammal species on the planet (http://buff.ly/1pxxt0k). They can vary in weight from 6 lb (3kg) to 200 lb (90kg) when fully grown and have widely differing body shapes and hair types.
Not surprisingly, dog-bite injuries in children (head and neck) peak in warmer weather. The family pet is to blame in 27% of cases, and pit bulls are most commonly involved.
Dog bites are the third leading cause of emergency room visits for children, and the majority of those bites are from a dog known by the child. The ASPCA's Director of Anti-Cruelty Behavior Research Dr. Katherine Miller discusses How to Avoid Dog Bites in this WSJ video:
Pay attention to the dog's body language
Put a safe amount of space between yourself and a dog if you see the following signals, that the dog is uncomfortable and might feel the need to bite:
pulled back head and/or ears
eyes rolled so the whites are visible
What to do if you think a dog may attack
Resist the impulse to scream and run away.
Remain motionless, hands at your sides, and avoid eye contact with the dog.
Once the dog loses interest in you, slowly back away until he is out of sight.
If the dog does attack, "feed" him your jacket, purse, bicycle, or anything that you can put between yourself and the dog.
If you fall or are knocked to the ground, curl into a ball with your hands over your ears and remain motionless. Try not to scream or roll around.
Here is a brief 3-minute summary from CNN with some practical tips how to prevent dog bites:
How to Avoid a Dog Bite : The Humane Society of the United States http://buff.ly/1jTA6UO
How to avoid dog bites | Cesar Millan http://buff.ly/1gk2Gng
Dog-bite injuries in children peak in warm weather | Reuters http://buff.ly/1jTAhj4