A father died after suffering an "incredibly rare" allergic reaction when he was bitten by a horsefly in Devon, reports the Press Association.
Andy Batty, 48, had been watching his daughter Catherine, 17, ride her horse when he received the bite.
The father of four, who was 6ft tall, collapsed as a result of anaphylactic shock and was pronounced dead by paramedics at the scene.
Mr Batty, an engineer, had been helping Catherine ride her pony Bess at a field in Brixham, Devon, on Sunday.
Two ambulances and a helicopter went to the field at 12.30pm but could not save him.
Lindsey McManus, deputy chief executive at Allergy UK, said: "Anaphylaxis to a horsefly bite is incredibly rare. It is more common for people to develop localised infection and pain around the bite.
"As with any allergic reaction, the sufferer would have previously developed antibodies, in this case, to the horsefly allergen by being bitten previously.
"The body's immune system reacts on further contact by producing chemicals such as histamine, which cause the symptoms that we recognise as allergy, including itching, swelling, rashes, and in the most severe form, anaphylaxis.
Mr Batty had four children - James, Michael, and Rachel from a first marriage, and Catherine from a second relationship.
He worked as an engineer at KJ Engineering in Brixham, under boss Keith Iszard.
Mr Iszard told the Herald Express: "Andy was a big fellow. He was 6ft tall and very broad like a rugby front row man. He could lift any weight.
"We couldn't believe a small fly could knock him down. His death has come as a massive shock to everyone here."
Mr Batty had also volunteered as a gateman at Brixham Rugby Club for the past three years.
Chris Forster, chairman of the rugby club, said: "Andy was a lovely guy, always willing to help and stop and talk.
"He started being involved in the club, as many of our members do, in the social way, using the members' club to drink.
"Then he started to get into the rugby. He started to help us as a volunteer about three years ago.
"He and Charlotte used to help together. I knew she had a horse and he used to go with her.
"Andy was certainly a big guy. His death has come as a huge shock to us all. When I got the call on Sunday evening, I was flabbergasted.
"I wasn't aware that he had an allergy to horseflies.
"He was in the club at the weekend, talking to one of the members."
Horsefly bites can be very painful, with symptoms including dizziness and wheezing as well as a lump around the affected area.
The insects cut the skin when they bite - rather than piercing it - so the wound can take a long time to heal and cause infection.
Mr Batty's funeral will be held at Torquay Crematorium next month, with a wake for friends and family at the rugby club.
The club will also hold a minute's silence in memory of Mr Batty at the first game of the season, on September 1.
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