Infected: Nina Pham was the first nurse to contract Ebola. Credit:AP Ms Vinson was isolated immediately after reporting a fever on Tuesday, Texas Department of State Health Services officials said. The circumstances under which Ms Vinson travelled were not immediately known. But the latest revelation raised fresh questions about the handling of Duncan's case and its aftermath by both the hospital and the US Centres for Disease Control and Prevention (CDC). CDC Director Dr Thomas Frieden told CNN that the second Ebola patient should not have travelled on the plane as protocol outlined that any healthcare workers who treat Ebola patients are not allowed to take public transport. At least 4447 people have died in West Africa in the worst Ebola outbreak since the disease was identified in 1976, but cases in the United States and Europe have been limited. The virus can cause fever, bleeding, vomiting and diarrhea, and spreads through contact with bodily fluids.

In September, Thomas Eric Duncan became the first patient in the US diagnosed with Ebola. He died in Dallas last week. Credit:AP "Health officials have interviewed the latest patient to quickly identify any contacts or potential exposures, and those people will be monitored," the health department said in a statement. During the weekend, 26-year-old nurse Nina Pham became the first person to be infected with Ebola in the United States. She had cared for Duncan during much of his 11 days in the hospital. He died in an isolation ward on October 8. Police tape and a 'No Trespassing' notice are posted in Dallas, at the apartment of a healthcare worker who treated Ebola patient Thomas Eric Duncan and tested positive for the disease. Credit:AP The hospital said on Tuesday that Ms Pham was "in good condition."

News of the second nurse's diagnosis follows criticism of the hospital's nurses of its initial handling of the diseases, in a statement on Tuesday by National Nurses United, which is both a union and a professional association for US nurses. The nurses said the hospital lacked protocols to deal with an Ebola patient, offered no advance training and provided them with insufficient gear, including non-impermeable gowns, gloves with no taping around wrists and suits that left their necks exposed. 'Piled to the ceiling' Basic principles of infection control were violated by both the hospital's Infectious Disease Department and CDC officials, the nurses said, with no one picking up hazardous waste "as it piled to the ceiling." "The nurses strongly feel unsupported, unprepared, lied to, and deserted to handle the situation on their own," the statement said.

The hospital said in a statement it had instituted measures to create a safe working environment and it was reviewing and responding to the nurses' criticisms. Speaking early on Wednesday on CBS This Morning, US Health and Human Services Secretary Sylvia Burwell declined to comment on the nurses' allegations. Dallas Mayor Mike Rawlings said at a news conference on Wednesday that the second infected nurse lived alone and had no pets. He said local health officials moved quickly to clean affected areas and to alert her neighbours and friends. A decontamination could be seen taking place at her residence. Early wake-up

Residents at The Bend East in the Village apartment complex were awoken early on Wednesday by text messages from property managers saying a neighbour had tested positive for Ebola, and pamphlets had been stuffed beneath doors and left under doormats, said a resident, who asked not to be named. Other residents were concerned enough that they were limiting time spent outdoors. "Everybody thinks this won't happen because we are in the United States. But it is happening," said Esmeralda Lazalde, who lives about 1.5 kilometres from where the first nurse who contracted Ebola resides. Texas Health Presbyterian Hospital is doing everything it can to contain the virus, said Dr Daniel Varga of Texas Health Resources, which owns the hospital. "I don't think we have a systematic institutional problem," he said at a news conference on Wednesday. At the same briefing, Dallas County Judge Clay Jenkins, the county's chief political officer, said authorities were anticipating additional possible Ebola cases.

"We are preparing contingencies for more, and that is a very real possibility," Jenkins said. The CDC said in a statement that it was performing confirmation testing of Texas' preliminary tests on the new patient. CDC Director Dr Thomas Frieden said on Tuesday the agency was establishing a rapid-response team to help hospitals "hands on, within hours" whenever there is a confirmed case of Ebola. Frieden has come under pressure over the response and preparedness for Ebola, but White House spokesman Josh Earnest said US President Barack Obama was confident of Frieden's ability to lead the public health effort. Reinforcements

Burwell, in a series of television interviews on Wednesday, said officials were adding staff to ensure the hospital in Dallas followed procedures to prevent transmission of the virus. She said there would be round-the-clock site managers to oversee how healthcare workers put on and remove the protective gear used when treating Ebola patients. In addition to extra CDC staff on site, two nurses from Emory University, in Atlanta, which has a specialised hospital that has treated other Ebola patients flown in from West Africa, were in Dallas to train staff. Obama was due to hold a video conference on Wednesday with British, French, German and Italian leaders to discuss Ebola and other international issues, the White House said. Prospects for a quick end to the contagion diminished as the World Health Organisation predicted that Liberia, Sierra Leone and Guinea, the three worst-hit countries, could produce as many as 10,000 new cases a week by early December.

Reuters, MCT