[Umaeril]

Rubor, calor, dolor, tubor (et functio laesa) are the usual signs of infection. If it is red, warm, painful and raised up then it is probably infected. I tell you I, personally, would be careful since multiple types of bacteria can cause necrotizing fasciitis.

Anyhow there is not much you can do but you should let her know about that girl in the hospital who has lost her leg, part of her abdomen and now her fingers because her leg got infected. It's like front page CNN.