Deaths from the MERS coronavirus have surged in Saudi Arabia ahead of the hajj pilgrimage, with 19 fatalities recorded in a week, according to health ministry statistics.

A total of 502 people have died in the kingdom since the virus first appeared in 2012, according to updated figures posted on the ministry's website, including 19, all Saudis, since last Thursday.

The number of MERS infections has also surged to 1,171 cases, the website said.

A surge in infections forced health authorities to shut the emergency  ward at a main hospital in Riyadh last week, after at least 46 people, including medical staff, contracted the Middle East Respiratory Syndrome.

Saudi Arabia, preparing to host more than two million Muslims from all over the world next month for the annual hajj to Islam's holiest sites in Mecca and Medina, is the country worst hit by the coronavirus.

MERS is considered a deadlier but less infectious cousin of the Severe Acute Respiratory Syndrome (SARS) virus that appeared in Asia in 2003 and killed hundreds of people, mostly in China.

Its symptoms can include fever, coughing and shortness of breath. There are no approved vaccines against MERS, which is believed to originate in camels.