The global coronavirus pandemic has shown a wide range of symptoms – from muscle cramps to hives – but some of the strangest yet have been observed in a couple of doctors from Wuhan Central Hospital, in China.

Dr Yi Fan and Dr Hu Weifeng, both 42, were diagnosed on the same day – January 18. They became critically ill and spent weeks in hospital.

While there, their skin turned black in the fight against the deadly disease.

Chinese state broadcaster CCTV reports that Dr Yi, a cardiologist, recovered from Covid-19 after doctors hooked him to a life-support machine for 39 days.

Dr Yi told CCTV that he had made an almost full recovery. He still wasn’t able to walk unaided but was sitting up and talking.

He told a reporter: “When I first gained consciousness, especially after I got to know about my condition, I felt scared. I had nightmares often.”

He said the battle with coronavirus had affected his mental health, as well as his physical condition, and he needed counselling as part of his recovery.

His colleague, Dr Hu, had an even harder struggle. Dr Li Shusheng, who treated him, said that Hu’s mental health suffered greatly as a part of his fight with coronavirus.

Dr Li said that the change in the doctors’ skin colour was probably a result of some of the medication used in their treatment, although he didn’t specify which medicine was involved.

He said that he expected both medics' skin colour to return to normal after the function of their livers improves.

The pair worked alongside Doctor Li Wenliang, who was warned by police against by police to "making false comments” about the pandemic, before dying of the disease on February 7. According to Chinese site Pear Video, his wife is due to give birth in June.