This is not good....

IMPORTANT: The most aggressive strains of Sars-CoV-2 could generate 270 times as much viral load as the least potent type 🦠 https://t.co/7DgtmwWwrP

— Spencer Wells (@spwells) April 21, 2020

“Sars-CoV-2 has acquired mutations capable of substantially changing its pathogenicity,” Li and her collaborators wrote in a non-peer reviewed paper released on preprint service medRxiv.org on Sunday.

Li’s study provided the first hard evidence that mutation could affect how severely the virus caused disease or damage in its host.

Li took an unusual approach to investigate the virus mutation. She analysed the viral strains isolated from 11 randomly chosen Covid-19 patients from Hangzhou in the eastern province of Zhejiang, and then tested how efficiently they could infect and kill cells.

The deadliest mutations in the Zhejiang patients had also been found in most patients across Europe, while the milder strains were the predominant varieties found in parts of the United States, such as Washington state, according to their paper.

A separate study had found that New York strains had been imported from Europe. The death rate in New York was similar to that in many European countries, if not worse.