Oakmoth poses threat to asthma and allergy sufferers as well as oak trees in west London.


The oak processionary moth, which has been in the UK since 2008, is covered in sharp hairs containing toxins during its caterpillar stage. The toxin in the hairs cause a release of histamine (an allergic reaction) when it touches the skin while the caterpillars pose a significant threat to people with asthma, as the toxin-containing bristles of the caterpillars can become airborne and trigger severe asthma attacks. People with asthma should always carry a reliever inhaler with them in case of unexpected asthma attacks, but especially if they are likely to be anywhere near affected trees.

Experts at Kew have discovered that spraying the caterpillars with insecticide in early May before they produce their poisonous hairs is the best way to tackle the problem. As a caterpillar, each oak processionary moth has around 62,000 hairs, which they can eject at will and hairs that fall to the ground can be active for up to five years. The moths only live for two to three days in July or August.

The problem is currently confined to south west London - particuarly Kew Gardens but experts are concerned that the oak processionary moth could take hold in Richmond Park, which is home to 40,000 oak trees over 2,500 acres.

Courtesy of BBC News Health

First Published in August 2010

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