New outbreaks of stinging oak processionary moth (OPM) caterpillars have been confirmed in the UK – just weeks after AG warned the pest posed a major hazard to health.

Caterpillars have 70,000 toxic hairs

Residents of Pangbourne in Berkshire and five west London boroughs have been told not to touch OPM caterpillars that are emerging from their nests.

OPM caterpillars are covered in 70,000 tiny toxic hairs which cause severe skin and eye irritations.

“We strongly advise people not approach the caterpillars or their nests because of the health risks,” said Dr Brian McCloskey, director of the Health Protection Agency.

“Pets can also be affected and should be kept away. Anyone who experiences an itchy skin rash or other allergic symptoms after being near oak trees should consult their GP.”

OPM spread to the UK from continental Europe on imported nursery stock. This spring, Government experts said they would no longer enforce eradication of caterpillar outbreaks.

Arborists said last week that eliminating the pest was now “impracticable” in London’s Ealing, Brent, Hounslow, Hammersmith and Fulham and Richmond-upon-Thames.

Deputy head of the Forestry Commission’s Plant Health Service, Stewart Snape, called on gardeners to report OPM outbreaks in oak trees.

“The public must not try to remove caterpillars or nests themselves,” Stewart said. “These jobs need to be perfectly timed to be most effective and are best done by specially-trained and equipped operators.”

OPM gets its name from caterpillars’ habit of moving about in nose-to-tail processions. The peak danger period for human health is mid-May to the end of June.

Anyone suffering from suspected sting symptoms should call NHS Direct on (0845) 4647.