Forty-eight hours after being struck by Khalid Masood’s Hyundai on Westminster Bridge, Francisco Lopes was in no doubt about his good fortune in surviving the attack that claimed four other lives.

“Just being here is amazing,” the 26-year-old, who suffered serious leg and hand injuries, said from his hospital bed on Friday. “You never think [something like] that is going to happen to [you], and it’s just wonderful to be here. Like my uncle told me, just take it as a new life. You are born again.”

But having been seized by a fear, in the moments after the crash, that he was going to die, Lopes is still traumatised by his experience. “I’m happy to be alive, but sleep is more difficult, because I see the car hitting me. I see it all the time.”

More than 50 people of at least 12 nationalities were injured in Masood’s murderous rampage across the bridge on Wednesday, 31 of whom required hospital treatment. Three days after the attack, 17 remain in hospital, two in a critical condition, with one person’s injuries considered life-threatening.

One of the three Metropolitan police officers who were injured by Masood on the bridge suffered “life-changing” injuries, it has emerged, though his condition is not believed to be critical. PC Kris Aves was walking back from a commendation ceremony with colleagues PC Roger Smith and PC Bradley Bryant when they were hit by the 4×4.

The 35-year-old father needed eight hours of surgery, and is now recovering with his parents by his bedside. His sister Nikki Tapner told the Sun: “All I have been told is that he has been hurt but his life is not in danger.”

Smith, in his early 50s, also underwent surgery for “significant” leg injuries, while Bryant was discharged after being treated for minor wounds.

The condition of the woman who was rescued from the Thames has stabilised since she underwent surgery to remove a clot on the brain, Romania’s ambassador to the UK said on Friday. Dan Mihalache told the BBC that Andreea Cristea, 29, and her boyfriend, Andrei Burnaz, had come to London from their home in Constanta, on the Black Sea coast, to celebrate a birthday, and that he had been planning to propose to her.

“It is quite a miracle that she could survive this very complicated experience, because she was practically thrown into the Thames,” he said. Cristea has not regained consciousness, but is making positive progress, he said. Burnaz, who suffered a broken foot when he was hit first by the car, has been discharged from hospital.

Meanwhile, Melissa Cochran, whose husband Kurt was killed after he was struck and thrown from the bridge, is continuing to recover from a broken leg, rib and a cut to the head, according to relatives. The couple, from West Bountiful in Utah, USA, were spending the last day of a European tour to celebrate their 25th wedding anniversary in London. Melissa’s parents live and work there as Mormon missionaries, a spokesman for the Church of Jesus Christ of Latter-day Saints confirmed.

Clint Payne, Melissa Cochran’s brother, said the couple were among the first to be hit by the 4×4; a GoFundMe page set up to support the bereaved woman, who is self-employed, had raised more than $57,000 (£46,000) on Friday night.

Most of the party of 90 15- and 16-year-olds from northern France who were caught up in the attack returned to Quimper in Brittany on Thursday, leaving three of their classmates still receiving treatment. The mother of one, known only as Thomas, said he had no memory of what had happened, and had been “relieved and happy to see us” when they arrived at his bedside on Wednesday evening.

Some of the injured at King’s College Hospital were visited on Friday by Prince Charles, who thanked staff for their “marvellous efforts”. Travis Frain tweeted a photograph of himself with the rince, which also showed the 19-year-old’s arm in plaster and leg strapped into a support.

Frain, a politics-obsessed student at Edge Hill university who had been visiting parliament for prime minister’s questions, told friends on his Facebook page that he had broken his left hand and fractured his leg. “I’m not too bad, though things are obviously still in the air, this early,” he wrote. After having x-rays on more than 20 parts of his body, as well as multiple MRI, ultrasound and CT scans, Frain, from Darwen near Blackburn, said his injuries “could have been a hell of a lot worse”, but still believes he will need months of physio before he is fully able to walk again.

Others among the injured include Patricia Neis-Beer, a German national who lives in Bridgewater, South Australia, who was in Britain on holiday visiting her daughter. “She’s had an operation on her foot, which was crushed – I guess crushed is the right word – by the vehicle,” Australia’s high commissioner to the UK, Alexander Downer, told a local television station, adding that he planned to visit her in hospital on Saturday.

“She lives in Bridgewater, where I come from in the Adelaide Hills, and works in a cafe in Stirling, a nearby township which I’ve used on hundreds and hundreds of occasions over the years,” he said.

Five South Koreans were injured, the country’s foreign ministry said in a statement. Three woman and one man in their 50s and 60s suffered injuries including broken bones, while another woman in her 60s suffered a head injury while falling, and underwent surgery.

The Greek couple who were caught up in the incident left London on Friday to continue their holiday in the UK, according to the country’s embassy press attache. “We have spoken to them today and can confirm that although they went to the hospital, five or six hours after the attack, only one, the woman, had sustained very minor injuries.”

Similarly, Ireland’s deputy prime minister Frances Fitzgerald told the Dáil that the injuries suffered by the Irish person caught up in the attack were not considered life-threatening.

People from Poland, China and Italy were also among those injured, Theresa May told the House of Commons on Thursday.