A mum and her daughter were in critical condition in hospital from multiple snake bites after wandering into a nest of adders.
The unnamed victims were out walking their dog at a beauty spot.
Emergency services were called and anti-venom treatment was urgently sent to them.
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It happened at Braunton Burrows, near Barnstable, Devon, on Friday (27 Jul).
Adders are the only venomous snakes in the UK.
Bites are not usually serious, but can be fatal.
They were rushed to North Devon District Hospital where they were said to be recovering, as reported by Need To Know.
Pal, Jo Gray said: “Urgent notice to walkers.
“My friend and her daughter spent last night in the Intensive Care Unit in critical condition after being bitten by adders on the Braunton Burrows.
“They may have disturbed a nest or a pair of mating adders as her daughter was bitten twice.
“Obviously this has been a very scary incident and she really wants to share awareness of the severity of this.”
She added: “This was not on one of the main paths, but one of the cut-throughs to the beach.
“Please take care and wear appropriate footwear and leg coverings if walking.
“They are both going to be okay after a really scary night but will be in hospital a little while longer.”
A rider from South West Blood Bikes which normally transports blood and organs was dispatched to carry the anti-venom.
A spokesman said: “Just before 9:30pm last night volunteer controller Adrian took a call for a job that was very different from our regular calls.
“North area volunteer driver Lee was dispatched to meet Freewheelers EVS volunteer rider Colin at Junction 25 of the M5 at 11.45pm to collect a package containing anti-snake venom treatment which was needed urgently by North Devon District Hospital.
“The handover took place just before midnight and Lee safely delivered it to the staff at the hospital just after 1am on Saturday.
“Great teamwork between two separate blood bike groups both supporting the NHS and the patient completely free of charge.”
Later, the original author, Jo Gray, added: “My friend is still in the intensive care unit but all being well should make a full recovery.
“Her daughter is out of the ICU but is still in the hospital.
“When she came round this morning after being sedated through the night her first concern was to make others aware of the potential dangers of a seemingly harmless adder bite – hence my post, upon her request.
“Both my friend and her daughter are fit and healthy and have walked the burrows day in and day out for years.
“This is a popular route taken by many including myself on a regular basis.
“Her dog got off scott free.”
On Sunday, a warning was issued by Braunton Burrows Public Information.
It read: “This follows an incident on Braunton Burrows on Friday involving two Burrows visitors getting adder bites which required a visit to hospital.
“Adders are found throughout Braunton Burrows just as they are in many North Devon coastal and countryside spots during the summer.
“This information is carried on Burrows visitor boards.
“They like to bask in the sunshine so at this time of year it always pays to be vigilant especially when using paths off the beaten track with poor line of sight.
“Adders are not aggressive by nature but will react in defence usually when stepped on or disturbed by dogs.
“We wish the two who got bitten a speedy recovery.”
Local, Belinda George said she had also encountered adders.
“Hope they feel better soon,” she said.
“It can take up to six weeks to feel fully better so try not to worry if off colour for a while.
“We’ve got nests in our field with massive adders.
“We think one of our horses got bitten because his face was very swollen, the vets could find nothing obvious in his blood and he was poorly for weeks.
“Might have been a hornet, we don’t know.
“But he’s well over 500kg and it’s taken him a month to recover.
“They’re no joke.”
Geoff Morton added: “This is an isolated case.
“I know it’s upsetting to hear however if you stick to the main paths you are less likely to encounter them.
“They are not only on the Braunton Burrows, they are all over our countryside.
“They have probably been basking as they are cold-blooded and need to warm up and the person has likely stood on it and tried to defend itself.
“Most of the time they disappear as they feel the vibrations from you walking.”
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