Another Qatari with the infection died in a London hospital on June 28.
The virus has killed 46 since September worldwide, 39 of them in Saudi Arabia which neighbours Qatar.
MERS is considered a cousin of the SARS virus that erupted in Asia in 2003 and infected 8,273 people, nine percent of whom died.
Like SARS, it is thought to have jumped from animals to humans, and shares the former's flu-like symptoms -- but differs by causing kidney failure.
Researchers have pointed to the Arabian, or dromedary, camel as a possible host of the virus.
Scientists studying the new virus have found older patients, men and people with underlying medical conditions are those particularly at risk.