It`s Kemushi (Caterpillar) season! Take care to avoid these “hairy” caterpillars as they have developed hairs or sharp spines that are capable of transmitting various toxins causing inflammation and hives on the skin. In most cases direct contact with the insect is necessary to provoke a reaction. However, the irritating hairs can also be detached and can go airborne adhering to skin or clothing causing a rash.
I found myself with an irritating rash on my neck and arm last week. I hadn`t come anywhere near a caterpillar. My doctor said the caterpillar hairs could have blown onto my skin, as he had seen this in many cases.
If you find yourself or your child with a rash or hives please consult with your dermatologist. It might be a reaction from kemushi (hairy caterpillars) and can be easily treatable.
Symptoms: Redness, rash, itchiness, small red bumps and pain.
Treatment: Remove the caterpillar hairs with tweezers or sticky tape. Wash the area with soap and water. Keep the area cool. Clothing should be removed and laundered thoroughly.
Contact a dermatologist. They will prescribe topical steroids or oral antihistamines to treat the inflammation and irritation.
Usual Length of Treatment: Depends on how severe the condition is and the prescription strength – usually one to two weeks. Strong topical steroids are normally not used for more than one week.
Types of Hairy Caterpillars:
– Tussock moth (ドクが): Feeds on Sakura, Ume, Roses & Japanese Knotweed
Peak Season: May & June
– Tea Tussok Moth/Japanese Browntail Moth (チャドクガ): Feeds on Japanese Camellia
Peak Season: May, August & September
– Yellow-tail, Goldtail Moth or Swan Moth (モンシロどクガ): Feeds on Sakura, Ume, Apple, Chestnut, Oak and Mulberry Trees
Peak Season: May, July & September
P.S. Visit our list of English Speaking Tokyo Dermatologists.
Inflammation and Hives from Kemushi (Caterpillars)