'My son died in his sleep from delayed allergic reaction'

A mum is calling for more research and allergy awareness after her 25-year-old son died from a delayed anaphylactic shock.

Jenson Joseph, 25, died in his sleep at home in York in April 2024, though what triggered the reaction has never been identified.

He had been diagnosed with a peanut and almond allergy in 2019 and was prescribed adrenaline auto-injectors (AAIs), but never had the need to use them. No traces of nuts were discovered during a post-mortem toxicology test.

His mum Alexa Metcalfe said she did not know about delayed anaphylactic reactions until Jenson's death and wanted to alert others to the risk.

"Jenson was incredible, everything that a mum would want. He was charming, kind, caring, focused, a great personality and would light up any room he went into," said Metcalfe.

"I never thought for a second that there was such a thing as a delayed reaction, I also never thought that any type of anaphylactic reaction could do that to you in your sleep.

"It is incredibly rare, which is why it's so important that we raise awareness. Jenson was so fit, so healthy, and so strong, he wasn't a poorly man or child. So it's even harder to start to accept that this type of thing can happen."

Jenson, who moved from his home in Shipley to York to study at York St John University, never had an allergic reaction after his diagnosis, and was "very careful about what he ate", never needing to use his AAI, said Metcalfe.

"He had not woken up that morning. The coroners concluded he had died from a catastrophic anaphylactic reaction," she said.

"I was absolutely devastated and actively sought out other professionals to get a second opinion and a third opinion and they all said the same thing."

According to Tanya Ednan-Laperouse, co-founder of the Natasha Allergy Research Foundation, the number of life threatening anaphylactic reactions has tripled in the last 20 years.

There were more than 25,000 anaphylactic reactions annually in 2022-23 and food-induced anaphylaxis accounted for 30% of these cases, with peanuts, tree nuts, and cow's milk the most common triggers, according to the government.

Ednan-Laperouse and her husband, Nadhim, started the charity when their daughter Natasha died from an allergic reaction to a sandwich she had eaten at Heathrow Airport in 2016.

"The word allergy for a lot of people brings up hay fever, maybe a rash, and I don't think many people realise that it can be life threatening," she said.

"It is very rare and it's absolutely heartbreaking but no matter how rare something is, there are always people who are affected, someone passes away and their families are never the same again."

On Saturday, a group of Jenson's friends from York St John University and Shipley completed a five-day 115-mile (185km) run from Villa Park in Birmingham to Valley Parade in Bradford in his memory and to raise money for the Natasha Allergy Research Foundation.

Jenson, who worked at David Lloyd gym in York, supported Aston Villa and Bradford City, with the friends deciding to run between the clubs' grounds.

Lead runner Alistair Harvey was living with Jenson when he died two years ago.

He described the challenge as a "fitting way" to pay tribute to their friend.

"It's been an amazing experience - some of the battles we've had to go through have been tough but we've got through it together as a team and that's been the whole point," he said.

Group member Joe Finnegan, who came up with the idea for the challenge, said Jenson was "the nicest man you'll ever meet, the funniest lad".

"We've all been speaking about Jenson all week and everyone sticking together was the best thing we could do," he explained.

Jack Drummond said that finishing at Valley Parade in front of Jenson's family and friends had been "emotional".

"It's obviously an honour to do it for him, to show how much we loved him and how much we respected him," he said.

"That's all for Jenson - it's bigger than us."

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