Factbox: Ebola cases in the United States

(Reuters) - There have been eight cases of Ebola seen in the United States since the beginning of August. A Liberian man who died Oct. 8 in a Dallas hospital was the first person diagnosed with the virus on U.S. soil. Two hospital employees who cared for the man have been infected with the virus, which has killed more than 4,500 people and infected more than 9,100 in the worst outbreak on record, centered in three impoverished West African countries: Guinea, Sierra Leone and Liberia. The following are details of cases of the hemorrhagic fever seen in the United States: NURSES Nina Pham, 26, a nurse at Texas Health Presbyterian Hospital, where she helped treat Liberian patient Thomas Eric Duncan. Officials announced Oct. 12 that Pham had been infected with the virus. She was moved to the National Institutes of Health in Bethesda, Maryland, where officials have said she is in fair and stable condition. A second nurse at the same hospital who treated Duncan, 29-year-old Amber Vinson, also tested positive for the virus, which spreads through contact with bodily fluids and can cause fever, bleeding, vomiting and diarrhea. She was transferred to Emory University Hospital in Atlanta, where she is doing well, according to an ABC News interview with her mother. Vinson flew from Ohio to Dallas the day before reporting symptoms, raising concerns about possible spread of the disease outside of Texas even as U.S. health officials say the risk of transmission is low. NBC CAMERAMAN Ashoka Mukpo, an American freelance television cameraman working for NBC News in Liberia, was flown out of the country for treatment at Nebraska Medical Center in Omaha. Mukpo, 33, continues to improve. "Recovering from Ebola is a truly humbling feeling. Too many are not as fortunate and lucky as I've been. I'm very happy to be alive," he said in a Twitter post this week. The NBC crew who worked with Mukpo also returned to the United States and were ordered into quarantine after violating their voluntary confinement. LIBERIAN IN DALLAS Duncan was visiting Dallas when he began feeling ill and sought treatment at Texas Health Presbyterian Hospital on Sept. 25. He was initially discharged with antibiotics, despite telling a nurse he had just come from Liberia. On Sept. 28 he returned to the same hospital by ambulance after vomiting outside the apartment complex where he was staying. Duncan died in an isolation ward 11 days later. EMORY PATIENT An unidentified American who contracted Ebola in Sierra Leone began treatment at Emory University Hospital on Sept. 9. The patient, who has asked to remain anonymous, was discharged on Oct. 19 and will make a statement soon, the university said. THREE MISSIONARIES Three Americans contracted Ebola while working for Christian missionary organizations in Liberia and were flown to the United States for treatment. All have recovered. Nancy Writebol contracted the virus in July while working for a SIM USA hospital with her husband, David, who was not infected. She was treated at Emory and discharged on Aug. 19. Dr. Kent Brantly also was treated in isolation at Emory after contracting Ebola while working for Christian relief group Samaritan's Purse. He was released on Aug. 21. Dr. Rick Sacra, a Boston physician who was working for SIM USA, arrived in the United States on Sept. 5 and was treated for three weeks at Nebraska Medical Center. UNDER OBSERVATION Hospitals across the United States have been urged to watch for possible cases and to ask patients about their travels to help screen for the virus. Patients have been monitored in Virginia, Maryland, Connecticut, Massachusetts, Kansas, Washington, Hawaii and Florida, but none tested positive for Ebola. (Compiled by Susan Heavey and Colleen Jenkins; Editing by Jonathan Oatis)