Hundreds of Britons are stranded on a cruise ship where four people have died after fellow passengers tested positive for coronavirus.
Cheryl Deeks, from the village of Mendelsham in Suffolk, told Sky News she is "on edge all the time" after being confined to her cabin since Sunday when the ship went on lockdown to stop COVID-19 spreading.
Mrs Deeks, 66, said she and her husband, David, are among more than 220 passengers from the UK on board the MS Zaandam, which set off from Buenos Aires on 7 March.
The cruise ship, operated by Holland America Line, is anchored off the coast of Panama with dozens of guests suffering from influenza-like symptoms and two testing positive for COVID-19, the disease caused by the coronavirus.
Holland America Line said on Friday that four "older guests" had died on the MS Zaandam.
The age and nationalities of those who died is unclear.
The cruise ship has been at sea since 14 March after Chile, where the cruise was meant to end in San Antonio on 21 March, refused permission for it to dock.
Panama's government also denied the MS Zaandam permission to dock on Wednesday.
On Friday night, coronavirus testing kits were brought onto the ship from the MS Rotterdam, another vessel operated by Holland America
The company is owned by Carnival Corp, whose Princess Cruises recently suspended voyages for two months after two of its quarantined ships became hotbeds for coronavirus infections.
Mrs Deeks, who is also on the trip with her 73-year-old sister Wendy, said only passengers showing symptoms have been tested.
She added there are not enough kits for all of the 1,243 passengers and 586 crew members on board.
The holidaymaker, who celebrated her birthday on the ship on 13 March, said: "We've been confined to our cabin since Sunday.
"It's wearing us down, we're just going stir crazy now really.
"We're totally stuck in the cabin, from the door to the bed and back is 24 steps.
"So I'm trying to do my 10,000 steps a day, and I'm walking backward and forwards doing 24 steps."
Mrs Deeks added that crew members leave their meals outside their cabin before knocking on the door and walking away as a precaution.
Holland America Line said the MS Zaandam was scheduled to head to Fort Lauderdale, Florida, after passing through the Panama Canal, and could arrive there on 30 March.
But Panamanian authorities said a transit of the canal would depend on a health inspection of passengers.
Mrs Deeks is now unsure of when her trip will come to an end.
She said: "I think that's the biggest problem because we're on edge all the time.
"We're physically well, but mentally we're quite stressed not knowing if we had a plan, if we knew for definite what was going to happen.
"I know they can't tell us, but it's just the not knowing that makes you feel uncomfortable."
Mrs Deeks said passengers over 70 are being moved on to the MS Rotterdam, meaning her sister Wendy will be leaving the MS Zaandam along with two friends.
Passengers without symptoms will also be transferred to the Rotterdam, it is understood.
Mrs Deeks said she is not sure how many people are ill on the vessel or what symptoms they are showing because they have been confined to their cabins.
She added that it appears the outbreak has not caused other passengers to panic.
Photographer Neil Bedford's parents Kim, 62, and Chris, 65, are among the British passengers on board.
They have been contacting him through WhatsApp and are starting to feel worried now they are confined to their cabin, he says.
"My mum was saying that until recently they were fine," said Mr Bedford, 38, from Bradford. "Now I definitely think, without her actually saying it, there's some panic setting in. She said yesterday she was feeling very sombre and they're not sleeping well.
"They're lucky because they have a room with a balcony, so at least they have that. Other people don't. They've seen dolphins and whales and my mum has sent pictures - I guess that's some light relief for them. She also said to say how well the captain and his crew have looked after them. She says he's been professional, honest and fantastic. He obviously must want to get home too.
"They've been there for a while but now it's starting to feel more serious and I just feel scared. I don't want to think the worst but you start to. Even when they get off the ship, what will their journey home be like? Will they be in quarantine or even be able to get a flight home? The world is changing so quickly, it's hard to know.
"I don't want to use the word anxious but there are so many things going round your head. I'm just trying to focus on thinking they'll be okay."
Newlyweds Yadira Garza and Joel Gonzalez, from Mexico, who are on their honeymoon on the ship, said the situation changed quickly, with them drinking wine on the deck one day and being quarantined in their small cabin the next.
"Last week I did 56,000 steps and this week I did 10,000. We have practically no movement," Ms Garza said.
She said the couple are wiping down water bottles and toiletries delivered by the crew to their door but have already run out of soap so are using shampoo.
On hearing they will be transferred to the Rotterdam, she said: "Today I got dressed, I'm not in pyjamas.
"They gave us the news that we could leave tomorrow, and I said, I'm going to get dressed to be ready."
Ian Rae, a London-based Scotsman on the ship with his wife, said most passengers were coping "pretty well" despite being in self-isolation since last Sunday.
"It's probably not an awful lot worse than the people back in the UK or anywhere else in the world at the moment," Mr Rae, a 73-year-old grandfather of four, told Reuters.
Mr Rae said he understood 229 British passengers were on board. Other guests included Americans, Canadians and Australians as well as Germans, Italians, French, Spanish and New Zealanders.
A Foreign Office spokesman said: "We are doing all we can to help British people on board the Zaandam cruise ship.
"Our staff are in close contact with the cruise operator and the authorities in the region to ensure British people can get home safely."