Epistaxis and bullae occurred in 35 of 54 cynomolgus macaques (Macaca fascicularis). Individual cases developed randomly during a 3 to 4 week period in the winter, and resolved within a week of onset. Clinical signs included nasal and eyelid swelling, bloody nasal discharge, sneezing, and bullous areas above the eyes. Affected animals remained active and alert. Staphylococcus aureus and Neisseria catarrhalis were isolated from nasal swabs. Hemagglutination inhibition titers for measles were negative. Biopsies of the bullous areas disclosed acute inflammatory edema and cellulitis.