Does a dog bite have to be reported?

I have a friend who was bit accidentally on the hand by her dog. Basically the dog caught his paw on his crate and hurt himself. When she went to help, her dog was in such a panic that he bit her on the hand. He’s a friendly dog and this is the first time he’s done this. Now her hand is hurt and swollen but she’s afraid of going to the doctor since she believes all dog bites have to be reported. Is this true? And does she have reason to worry about something happening to her dog? She lives in New York.