Processionary caterpillars

These are dangerous to pets, and must be treated with absolute caution. The Pine Processionary Caterpillar can injure or kill your dog and cause serious health problems for people.

What are processionary caterpillars ? 

The processionary caterpillar is the larval stage of a type of moth.  In order to metamorphose into a chrysalis, it first spends a certain time nourishing itself, mostly by feeding on pine needles (i.e. pine, cedar, etc.), around which it also weaves its silk cocoon. In spring, it then comes down from its tree in order to burrow underground and thus complete its transformation. Risk is particularly high at this time of the year, as the chance for our pets of coming into contact with them is considerably increased.

Note:  the term “processionary” originates from the habit these caterpillars have of travelling around together in single file.

Risks to animals

Be under no circumstance fooled by the non-threatening appearance of these caterpillars. They actually possess urticating hairs which are released when threatened or stressed. These hairs are different from the caterpillar’s visible hairs: each is equipped with a hook which attaches to the skin and/or the surfaces of other organs, then ruptures and delivers a highly dangerous toxin.

Though cats can be affected, it is mainly dogs, with their playful temperaments, that tend to be most attracted to these tiny crawling creatures. The muzzle and mouth are most often affected. However, because the urticating hairs are very volatile, it is not unusual for other parts of the body to be involved (e.g. the eyes and eyelids). If ingestion occurs, the digestive tract can also be damaged.

Symptoms in dogs and cats

Mouth 

In addition to the pain caused, there will be significant inflammation visible around the animal’s mouth and muzzle. Necrosis of the tongue can rapidly occur and could even cause some parts to fall off, depriving the animal of being able to eat properly.

Skin

Contact with the dog or cat’s skin will cause an aggressive rash with multiple red spots. Itching and swelling of the affected area also often occur.

Eyes

The fact that these urticatig hairs can seriously damage the eyes, any contact with eyes is very dangerous and very painful for the animal. Moreover, the hairs can cause inflammation of the conjunctiva and the cornea resulting into corneal ulcers. Without being treated properly, they can even cause complete loss of sight.

What to do in case of contact?

If contact with a processionary caterpillar occurs, rinsing thoroughly the affected area without rubbing is recommended. It is important to seek urgent medical care as the consequences can sometimes be serious and irreversible for the cat or dog. When treated rapidly, the chance of a full recovery without long-term effects are much better.