Now, his pregnant fiancée Carrie Symonds, 32, has thanked the “magnificent” NHS for the “incredible” care they gave the 55-year-old prime minister.
In a series of Twitter posts this afternoon, she revealed “dark” days during which she had been “worried sick”.
The senior advisor to ocean conservation charity Oceana said she felt “lucky” as she was reunited with her fiancé at their country home Chequers.
I cannot thank our magnificent NHS enough. The staff at St Thomas’ Hospital have been incredible. I will never, ever be able to repay you and I will never stop thanking you. 🌈— Carrie Symonds (@carriesymonds) April 12, 2020
There were times last week that were very dark indeed. My heart goes out to all those in similar situations, worried sick about their loved ones.— Carrie Symonds (@carriesymonds) April 12, 2020
Thank you also to everyone who sent such kind messages of support. Today I’m feeling incredibly lucky.— Carrie Symonds (@carriesymonds) April 12, 2020
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Her posts received thousands of ‘likes’, with many people leaving kind messages.
One person wrote: “Best wishes to you and Boris.”
Another commented: “Could not be happier for you!”
A third shared: “Amazing news Carrie!!”
It was announced by Downing Street that the prime minister had left St Thomas' Hospital in central London, but would not be immediately returning to work.
In a video message posted to his Twitter account after his seven-night hospital stay - during which he was also taken into intensive care - Boris said: "I have today left hospital after a week in which the NHS has saved my life, no question.
"It's hard to find the words to express my debt."
He also paid tribute to the "personal courage" of doctors, nurses, cleaners, cooks and other healthcare workers at the hospital.
The prime minister expressed particular thanks to two nurses - Jenny from New Zealand and Luis from Portugal - who "stood by my bedside for 48 hours when things could have gone either way".
He said: "The reason in the end my body did start to get enough oxygen was because for every second of the night they were watching and they were thinking and they were caring and making the interventions I needed.”
Carrie revealed in a post on Twitter earlier this month that she had been experiencing symptoms of COVID-19 and had been self-isolating.
At the time, she revealed that after a week of rest she was feeling “stronger” and was “on the mend”.
I’ve spent the past week in bed with the main symptoms of Coronavirus. I haven’t needed to be tested and, after seven days of rest, I feel stronger and I’m on the mend.— Carrie Symonds (@carriesymonds) April 4, 2020
Carrie - who is due to give birth in late May or early June - also acknowledged that being infected while expecting a baby is “obviously worrying” and directed mums-to-be to official guidance from the Royal College of Obstetricians and Gynaecologists.
In February, she announced in an Instagram post that she was engaged to the prime minister and carrying their first child.
Captioning a snap of the couple, she wrote: “We got engaged at the end of last year...and we’ve got a baby hatching early summer.”