A British couple who died in Egypt were staying at a hotel being fumigated to kill bedbugs, their inquest heard.
John Cooper, 69, and his wife Susan, 63, of Burnley, Lancashire, died in 2018 while on holiday in Hurghada with their daughter and three grandchildren.
The inquest heard the Coopers fell ill at the Aqua Magic Hotel during the early hours and died the next day.
The inquest heard a report pointed to possible exposure to an “infectious biological agent or toxic chemicals”.
Blackburn Coroner’s Court heard the report suggested neither carbon monoxide poisoning nor food poisoning caused the couple’s deaths.
A tourist from Germany said he reported a bedbug infestation in the room next door to the Coopers and it was then treated with pesticide, referred to as Lambda.
The two rooms had an adjoining door but this was kept locked.
Their daughter, Kelly Ormerod, described her parents as fit and healthy and had been enjoying a “brilliant” holiday.
Mr Cooper, a builder, and his wife, Susan, a cashier at a bureau de change in a Thomas Cook travel agent, enjoyed several holidays a year.
Mrs Cooper had been to the same hotel in April that year, described it as “fabulous” and decided to go back with her family.
Their 12-year-old daughter Molly had been staying on a single bed in her grandparents’ room, which she said had a “yeasty smell”.
In the early hours of 21 August, Mr Cooper rang to say she was feeling a little unwell and he escorted his granddaughter to her mother’s room in an upper floor.
The next morning, the couple failed to emerge for breakfast, so Ms Ormerod went to their ground floor room to discover the pair seriously ill.
Ms Ormerod said her father came to the door saying: “I really don’t feel very well,” with him retching and screwing his face up.
“He just literally slumped and sat on the corner of the bed and said: ‘I’m really not well,” the civil servant told the hearing.
She said her mother was in bed, “groaning”, with vomit in her hair and around the room, where she noticed a strange “heavy” smell.
Two doctors were summoned but they were in “panic mode”, Ms Ormerod said, as her parents further deteriorated and her father struggled to breathe.
Tearfully, Ms Ormerod added: “His eyes kind of… a glazed, staring look.”
Susan Cooper with daughter Kelly Ormerod
Kelly Ormerod, pictured with her mother, said her parents were healthy the day before they died
CPR was attempted but Mr Cooper was declared dead in the hotel room. His wife was taken to a clinic at the hotel where she became delirious, the inquest heard.
She was taken to hospital by ambulance but later declared dead.
Both were returned to the UK in sealed, zinc-lined coffins, the inquest heard.
A statement was read from Dominik Bibi, a truck despatcher from Germany, who arrived with seven family members in the early hours of 20 August.
Mr Bibi said his mother-in-law, who used a wheelchair, was booked to stay in the ground-floor room next to the Cooper’s room.
His statement added: “On entering I immediately noticed a funny smell, like that of mould or damp.
“There was a lot of bed bugs in the bed and under it.”
He said a cleaner and night manager came and apologised and his mother-in-law took his and his wife’s room, further down the corridor.
Hours later around lunchtime he was outside her room when he saw three men, two wearing the hotel uniform and the other with a two or three litre pesticide canister he assumed being used to get rid of the bed bugs.
Aqua Magic resort
The family had travelled to the Steigenberger Aqua Magic Hotel
After five or 10 minutes they left the room and used masking tape to tape up around the door and seal the room.
“I would not say the job was very professional,” Mr Bibi’s statement continued.
The hearing was adjourned until Wednesday morning.