THEY'RE hairy, they make people itch and they're back.

Caterpillars which have plagued Hampshire, leaving trails of irritated victims in their wake have been spotted again.

Experts are now warning residents to steer clear of the creatures, so poisonous they can put unsuspecting victims in hospital.

Headaches, nausea, vomiting, numbness, blisters and breathing problems are among the known side effects of touching the furry caterpillar destined to turn into a brown-tailed moth.

Now the venomous pests could be making a return to Hampshire where they caused havoc in the summers of 1997, 1998 and 2001.

Pensioner Hazel Way was shopping in Southampton when one fell on her head and sparked a painful red rash.

As she returned home to Alder Road, Maybush, it spread over her neck, shoulder, chest, arms and legs, and her skin broke out in lumps.

Experts fear the incident had all the hallmarks of a brush with a brown-tailed moth caterpillar.

Phil Harris, of research team Exosect, which started as a Southampton University project to control the numbers of brown-tailed moth caterpillars in the south, said: "This time of year is when the caterpillars are at their most toxic. They have tiny hairs which contain toxins and if you come into contact with enough of them you can come out in a nasty rash.

"Infestations do break out and you need to call out a pest control operator to get rid of them. Officers need to wear face masks and protective gear and the caterpillars have to be handled carefully."

He has helped develop a trap which attracts male moths and sprays them with female hormones to stop them reproducing - a long-term weapon that has been adopted by Southampton City Council.

Exbury Gardens head gardener Rachel Martin said: "They are mainly found on seaside plants and I have seen them on clifftops but I know that when you get a population explosion, you really do."

Several incidents have already been logged with the council's parks team, who say they're standing by with insecticide as a last-resort tool against the miniature menaces.

They also regularly patrol city parks in winter looking for the moth cocoons and cutting them out of trees.

Mr Harris added: "I would advise people not to touch the caterpillars, and keep pets and children away. People have been rushed into hospital with shock after coming into contact with the caterpillars before, they can be very dangerous."

Grandmother Mrs Way, 68, has also added her warning.

"I was sitting on a bench outside HMV when I felt something drop on my neck. At first I thought it was a leaf but when I hit it to the ground I saw that it was a hairy caterpillar.

"It was green and a little over an inch long but it quickly curled up."

Her GP prescribed anti-histamine tablets after telling her the rash would take three weeks to clear up.

"It is very sore and continually with me. I feel dreadful,'' she added.

The caterpillar, which goes by the name of Euproctis Chrysorrhea, caused the closure of a popular Isle of Wight beach seven years ago.

They have been a chronic problem in coastal areas in recent years, particularly in the New Forest, the Isle of Wight and Portsmouth.

Southampton pest controllers had to deal with outbreaks in both 1998 and 2001.