A DAD was forced to give up work after a bite from “Britain’s most dangerous spider” left him struggling to walk.

Window cleaner Adam Abrehart discovered a bite on his leg after returning home from a run near Shefford, Bedfordshire. Initially just itchy, the bite soon swelled in size and turned black, engulfing his lower leg, and forcing him to seek medical help.

The ordeal would ultimately land him in hospital for three days, and keep him out of work for a further week while he healed up at home.

As someone who works outside, Mr Abrehart is all too familiar with noble false widow spiders – and thinks the species is to blame.

He said: “I was running near the local river in Shefford, I don't know exactly where it happened.

“All I know is that when I finished, I just saw a couple of red dots in my leg and that was it.

“Over a couple of days it started itching a little bit, and then it went black, and the bite slowly started to get bigger.

“It went from about two to three millimetres to the size of a pea. Eventually, it was about the size of a 20p piece.”

Photos capture the growth of Adam’s injury from a small bite to a huge black wound covering his lower leg.

“When the infection took hold, that's when the pain started,” said Mr Abrehart.

“Beforehand it was just itchy, a bit of redness, but then the skin went all black and dark and horrible.

“I started feeling the swelling and my legs started hurting.

“I couldn’t walk properly after the infection took over… it really hurt to stand up straight.”

Initially Adam contacted the NHS 111 helpline and was advised to get antibiotics.

But it was a Sunday and the pharmacy was closed, so the 34-year-old tried to endure until Monday.

He said: “Throughout the night I suddenly got worse, I started being sick – really sick.

“I got a really bad headache and could barely open my eyes. I had a temperature as well.”

“It was just getting too much. I thought it was time to go to the hospital.”

The noble false widow is “widely regarded as the most dangerous spider breeding in Britain,” according to a 2020 paper by Clive Hambler, an Oxford University zoologist.

Known as Steatoda nobilis, they’re not native to Britain and are thought to have arrived from the Canary Islands in banana boxes in the late 1800s before slowly spreading northwards.

“I think I ran through its spider web, and then it didn't like me very much, so it had me,” said Mr Abrehart.

At the Lister Hospital in nearby Stevenage, he was put on a drip and admitted as an inpatient.

He said: “I’m self employed and it took me out of work.

“I was in there for three days. And then I was at home for about another week to a week-and-a-half."

Even now, a month later, he still has angry scars.

“It hasn't fully cleared up yet,” he said.

“It’s affected the whole of the month really.

“After the drip I had to take the oral antibiotic, two a day for the next week or so, and antihistamines.

“Then it was just a case of leaving it to heal, and checking on it.

“It got really swollen, so I had to keep it raised. Then every time I got up, I could feel it swelling.”

Yet despite the trouble, Adam bears no ill will towards false widows.

He said: “Just treat spiders with respect, don't go out murdering them all because they're not that bad, they’re just a little spider at the end of the day.”