The pine processionary caterpillar is a danger to humans
Unlike the vast majority of caterpillars, this particular species can be harmful to adults and young children because they have thousands of hairs containing a stinging, or irritating, protein called thaumetopoein.
Each caterpillar has about 500,000 small, highly stinging hairs along its body, which can easily become detached. This poses a risk, not only through direct contact, but also by air through the effect of wind currents, since, if they feel threatened, they can throw these hairs into the air.
In minor cases, the contact with this bristles will cause urticaria or a skin irritation like a nettle rash. An antihistamine cream will usually be enough to relieve the symptoms. In more severe cases, humans can experience allergic reactions or respiratory problems. Asthmatics are particularly vulnerable and at risk of having a severe attack.
Several dog owners have lose their pets after coming into contact with the pine processionary caterpillars every year, so it is important that you are familiar with them and the potential dangers.