It is important to follow up carefully once a child has had a urine infection, as repeated urine infections can cause damage to the kidneys. Most children who have a bladder infection are fine and have no underlying problem. Some children may have urinary reflux, in which the urine in the bladder backs up toward the kidney up the ureter when the child urinates. This makes a child more likely to have urinary infections. Children who have reflux usually take antibiotics on a regular basis in order to prevent further infections. They usually outgrow the reflux as they get older.
For children who are normal, good hygiene and drinking fluids regularly are the best preventive measures. For girls, always make sure that they are wiped from front to back (Meaning start where the urine comes out and wipe the cloth back to where the stool comes out). Don't wipe over the front again with the same cloth.