The first concern for anyone bitten by an animal is rabies, a usually fatal viral disease carried most often by wild animals but also by cats and dogs. A rabid dog will behave strangely, sometimes biting without reason or foaming at the mouth.
If you are bitten by a stray dog or one whose owner can’t be found, wash the wound with soap and water and see a doctor immediately. He will probably prescribe a tetanus shot; antirabies injections are rarely needed in cases of dog bites. To be safe, if the animal can be captured, have it impounded and observed for signs of rabies.
If the dog’s owner is known, find out whether the animal’s rabies shots are current. Even if they are, ask the owner to observe his pet for 10 days. Antirabies shots can be delayed that long and won’t be needed if the dog stays healthy.
The wound itself, if shallow, can be treated like an ordinary cut. If it is deep, requires stitches, or is potentially disfiguring or if you haven’t had a tetanus shot in 10 years see a doctor.