 The hairs cause itchy rashes (contact dermatitis) in many people, particularly those prone to allergies, and may resemble exposure to urushiol.They are microscopically barbed and may rarely cause serious medical complications if they are transferred from the hands to the eyes, but in over 350 documented cases, most were asymptomatic within 24 hours, and none involved anaphylaxis.The later-instar caterpillars are seen between July to October.