Oak processionary caterpillars, characterized by their toxic hairs, are causing widespread infestations across Europe. These caterpillars, often found in large numbers, can defoliate oak trees and their microscopic hairs can become airborne, causing severe itching and skin irritation upon contact, even through clothing. The hairs can persist on surfaces for years and cause significant discomfort, with potential for more serious issues like eye irritation or respiratory problems.

Recent years have seen a surge in these infestations, exacerbated by warm, dry springs, leading to outbreaks in countries like Germany, Britain, France, the Netherlands, and Switzerland. Cities like Berlin have struggled to manage the escalating problem, with requests for public health threat declarations and increased funding for pesticide use being denied. This has led to temporary closures of public spaces, such as playgrounds and swimming pools, due to the presence of caterpillar hairs.

Managing these infestations is becoming a significant challenge. While insecticides can be effective, they also pose risks to other caterpillar species. Companies specializing in pest control are seeing increased demand, with specialized equipment like aerial lifts becoming essential for removing caterpillar nests. The increasing frequency and intensity of these outbreaks suggest a need for adaptation, as experts believe these caterpillars are likely to become a more regular part of European summers.