Be VERY CAREFUL with her. I could be Purpura Hemoragica. This is a reaction a horse can have to Strangles or to the vaccine. I do not vaccinate and I have 50 head in a herd that is not closed. This is because I have seen more cases of purpura from vaccinations than from strangles, but they do occur. Purpura is life threatening and requires a LOT of doctoring to save them. Swelling is the first symptom.