A short lesson in natural sciences. The pine processionary caterpillar is the larva of a moth, the Thaumetopoea pityocampa. In the spring, the caterpillars leave the trees to bury themselves underground: this is a procession that can sometimes extend over 40 meters, in single file.
The problem is that the processionary caterpillars are extremely stinging: this power comes from a fine layer of dust which is detached from plates located on the back and the posterior part of the caterpillar. When this powder comes into contact with the skin, a painful rash accompanied by itching occurs within 8 hours. Worse: the stinging substance can spread over the body via itching, clothing, sweat or friction…
When the stinging dust comes into contact with the eyes, the appearance of a conjunctivitis within 1-4 hours – eyes become red, sore and watery. If the substance sinks into the tissues of the eye, this can sometimes progress to blindness.
Consequences that can be serious
In the event of contact by inhalation, this is manifested by sneezing, sore throat, difficulty swallowing and possibly difficulty breathing due to bronchospasm (narrowing of the bronchi as in the case ofasthma). And if there is ingestion, inflammation of the mucous membranes of the mouth and intestines occurs, which is accompanied by symptoms such as hypersalivation, vomiting and abdominal pain.
Usually, the first victims of processionary caterpillars are the pets. However, this Friday, March 17, 2017, 18 babies aged 1 to 2 years and 3 adults had to be hospitalized. The facts took place in a nursery in Septèmes-les-Vallons (Bouches-du-Rhône): the caterpillars fell from a tree “on the edge of the nursery which overlooked the courtyard”. The children, who were playing outside, then touched the tracks which were on the ground, explained the spokesperson for the fire brigade.
Fortunately, their hospitalization is “a precautionary measure: all stinging hairs must be removed and ointment applied to the skin”. Ten ambulances were nevertheless hired for the occasion by the firefighters, the Marseille firefighters and the Smur.