RIYADH — Health authorities said Thursday a man has died from the MERS coronavirus, bringing the death toll from the respiratory disease in the Kingdom to 62. The 55-year-old Saudi, who died in Riyadh from the Middle East Respiratory Syndrome, was suffering from “chronic illness,” the Health Ministry website said. The ministry also announced a new case in the province of Riyadh, bringing the total number of cases in Saudi Arabia to 150 people since the virus first appeared in September 2012. Experts are struggling to understand the disease, for which there is no vaccine.