At least one chapter of the Ebola saga neared a close Sunday, as most of the dozens of people who had direct or indirect contact here with Thomas Eric Duncan, the Liberian man who died of Ebola, had been told by officials that they were no longer at risk of contracting the disease. Mr. Duncan's fiancée, Louise Troh, who nursed him in their cramped apartment while he suffered from diarrhea and who was put under state-ordered quarantine, was set to be declared Ebola-free by officials at the end of Sunday. So, too, were the paramedics who drove an ailing Mr. Duncan to a hospital and health care workers who drew or processed his blood.