We know that pet rats can and will bite anyone if they feel threatened. Likewise, they can and will scratch, too. Pet rats have claws, so even if they are not intending to scratch, it is still very possible to get scratched. However, can pet rat bites be harmful in the same way as bites? Again, as with bites, yes, a scratch from a pet rat can be harmful. Not only do the actual scratches hurt at the time if they are deep, but they can cause severe complications.
Unfortunately, all rats can and do carry bacteria that cause infection. Depending on how your immune system reacts to them, and how capable it is of dealing with the infections determines how dangerous the scratch could be. However, as a general rule, 10% of scratches can become infected, which is not overly high. The problem arises when 10% of those infections are deadly. In 2014, a ten-year-old boy died from a scratch from a pet rat who had tested positive for S. moniliformis. Therefore, can pet rat scratches be dangerous? Yes, they most certainly can.