Child with bacteria infection.. pls help?

My housemates 1 year old has a bacteria infection. Can someone let me know what causes bacterial infections.

She was diagnosed with bacteria infection yesterday so they are still running tests. They said that her white blood count is high and that her heart is beating quickly.

My housemates and I always have disagreements about my dogs. Could the baby have gotten a bacteria infection from a dog? I grew up with dogs in the house as I know many people have. They think it could be different b/c we are in Jamaica.

BTW I live in Jamaica.

The child also has a bad habit of putting everything in her mouth.

The main question is how do people get bacteria infection and what do you do about it?