The first person to be diagnosed with Ebola Virus Disease, EVD in the United States of America, USA, Thomas Eric Duncan has died, a Dallas hospital has announced. The late Liberian, who recently travelled from West Africa to Dallas, had been in isolation at Texas Health Presbyterian Hospital in Dallas since 28 September. It wasnít immediately known what would happen to his body, which could remain contagious for several days. Guidelines from the Centers for Disease Control and Prevention call for the remains to be immediately shrouded in plastic and double-bagged in leak-proof bags at the hospital and promptly cremated or buried in an airtight casket. Duncanís death comes four days after his condition was downgraded from serious to critical. Over the weekend, he had begun receiving brincidofovir, an experimental antiviral drug, which recently gained emergency approval from the US goverment. Duncan, 42, is also the first person known to die of Ebola in the United States. The highly contagious virus has killed more than 3,400 people in West Africa in 2014, the World Health Organisation estimates. Five Americans who were diagnosed with Ebola in Africa have returned to the U.S. for treatment since late July. Aid workers Kent Brantly, Nancy Writebol and Rick Sacra made full recoveries. WHO said one of its doctors was transported to Emory University Hospital in Atlanta on 9 September. No other details have been released. Ashoka Mukpo, a cameraman working for NBC News, arrived at the Nebraska Medical Center in Omaha for treatment on Monday. Duncanís illness and treatment have sparked controversy. He arrived in Dallas on 20 September from Liberia, one of the hardest-hit areas of the outbreak. His neighbors in Monrovia told reporters that five days before his flight, Duncan helped a pregnant woman get to the hospital in a taxi. She was convulsing and vomiting. The woman died at home hours later, after being turned away from a crowded Ebola treatment ward. It is unclear if Duncan knew the woman had Ebola, but Liberian government officials said they plan to prosecute him for lying on health forms he completed at the airport on 19 September. Duncan answered ďnoĒ to questions about whether he had cared for an Ebola patient or touched the body of someone who had died in an area affected by Ebola. Officials said Duncan, who was reportedly coming to Dallas to be with his fiancee, didnít have a fever or symptoms of Ebola when he boarded his flight in Liberia. Five days after arriving in Dallas, a friend drove Duncan to the emergency room at Texas Health Presbyterian. Hospital officials said he showed up in the middle of the night with a fever of 100.1 degrees, abdominal pain for two days, a sharp headache and decreased urination. The hospital said Duncan told them he had not experienced nausea, vomiting, or diarrhea ó strong indicators of Ebola.