Oak tree procession spinner a health hazard

Oak Processionary Spinner especially dangerous for allergy sufferers

19/04/2011

The caterpillars of the oak processionary moths are on their way again. The warm weather of recent weeks favors the growth of the caterpillars, so that the above all dangerous for allergy animals currently massively multiply, warn the health authorities throughout Germany.

The fine hairs of the oak processionary spinners can cause violent allergic reactions on contact with skin or by inhalation, so that the massive spread of the pests is not only a danger to oaks, whose leaves destroy the voracious caterpillars almost completely, but also for humans. In particular, allergy sufferers should be careful because it threatens violent allergic reactions with weeks of itching to anaphylactic shocks.

Violent toxic reactions on contact with the caterpillars
The caterpillars of the oak processionary moths settle in so-called webs in the trees and eat their way through the foliage. Fine poisonous hair protects the animals from possible attackers, but these stinging hairs can cause severe allergic reactions in humans. Thus, in direct skin contact with the hairs threatens the so-called caterpillar dermatitis. The thaumetopoein contained in the burning hairs of the caterpillars causes painful toxic reactions on the skin. In wind, the fine hairs of the caterpillars can also be spread through the air and not only come into contact with the skin, but deep into the respiratory tract, where they can also cause allergic reactions to asthmatic episodes.

The stinging hair of oak processionary moths is accumulated in the environment
In order to stop the spreading of the oak processionary spinners in the cities, several cities such as Frankfurt (Main) decided to control the pests with the help of biological insecticides. In the coming week helicopters are to spray a good 150 hectares of urban forest with the biological insecticide, in addition, a fight from the ground out, said the Environmental Agency in Frankfurt. But the health hazard is not only directly from the caterpillars, but also from the webs. These contain after the pupation of the caterpillars the old larval skins and show a long time a high concentration of the burning hairs on. According to the experts, old webs are a persistent source of danger, and because the caterpillar hairs have a long shelf life, they are accumulated in the environment for years - with corresponding negative effects for allergy sufferers. (Fp)

Image: Caterpillar dermatitis (lepidopterism) caused by Oak Processionary (Thaumetopoea processionea), Photo: Daniel Ullrich. License: released in the GFDL and CC-by-sa-2.0-DE by Daniel Ullrich.