A coronavirus patient was able to come off ventilation just two days after receiving the blood plasma of people who have recovered from the virus in a breakthrough described as "remarkable" by scientists.

The first trials looking at whether antibodies of people who have successfully fought the virus can help others do the same found that all 10 severely ill patients made a speedy recovery.

The treatment, known as convalescent plasma (CP) therapy, was used during the 1918 Spanish Flu pandemic before vaccines or antivirals were available.

It relies on the fact that the blood of people who have recovered contains powerful antibodies trained to fight the virus.

There is currently no treatment for coronavirus, and vaccines are unlikely to be available until the end of the year at the earliest.

Researchers from the Shanghai Jiao Tong University School of Medicine said the findings suggest blood plasma therapy is a safe and promising treatment for severe Covid-19 patients, and called for larger clinical trials.