A teenage boy was left in hospital over the weekend after a bite from a false widow spider.
William Fraser, 14, from Benhill Road in Sutton, was bitten on Thursday night while he was asleep.
The next day, his whole forearm had become swollen.
His mother Sarah told the Metro: "We gave him an anti-histamine and paracetamol. The next day he seemed to get better but on Sunday he just got worse and worse. He was feeling ill and he had to go to bed.
"We got him up to St Helier and the doctors and nurses hadn't even heard of false widows."
He felt better after a strong dose of penicillin and was allowed home.
According to the Daily Mail, William wasn't the only person to be treated for a false widow bite in Sutton this weekend.
Alexander Giordano, 39, of Broomloan Lane in Sutton, was bitten on his shoulder and wrist.
His arm started hurting and his hand went numb, so he went to A&E and was put on a course of antihistamines, antibiotics and cream for the affected areas.
This incidents comes just days after reports that the unusually hot weather has caused a boom in the venomous spider across Britain.
The Steatoda noblis spiders, the most poisonous in Britain, originate from the Canary Islands. They have a distinctive marking on their back which looks like a white skull, and only usually bite if they feel threatened.
If bitten, most people will suffer localised pain and swelling after a bite, but in extreme cases it could trigger an allergic reaction known as anaphylactic shock, which can be fatal.
Last week, a man told how he nearly lost his leg after he was bitten by a venomous false widow spider in Essex.
Ricki Whitmore, from Collier Row, Essex, was bitten by a false widow while working at a school.
But conservation officer Greg Hitchock, who works at the Kent Wildlife Trust, has urged people not to panic.
He told the Daily Mail: "Lots of people said they have been absolutely sure that the spiders they have seen are false widows, but they're not at all. It's not that straight-forward.
"Many of the "sightings" reported are probably not false widows at all."
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