Impetigo or angina of the horse is a bacterial infection caused by Streptococcus equi. It is characterized by swelling and severe inflammation of the mucous membranes of the throat and head and an enlarged lymph nodes. This disease is highly contagious and streptococci can be isolated either in the nasal secretions or in the lymph nodes. The impetigo involves mainly young subjects who have lower immunity. Transmission occurs through contact between animals either directly or indirectly by man, the wall, buckets and everything on which nasal discharge may be filed. The clinical signs are an important hyperthermia, purulent nasal discharge, decreased appetite and a weak cough. This infection is usually quite mild, however, some severe forms are described.