Fears have been expressed at a top level meeting in Washington that the Ebola outbreak will spread globally and will become the next HIV-Aids if more urgent action is not taken to control it.
A nurse who treats Ebola patients being sprayed with chlorine. Photo: NZ Red Cross
Nearly 4000 people have died in West Africa and the number of confirmed and suspected cases outside the region is growing.
International health officials and government representatives from the worst-affected countries have taken part in a meeting hosted by the World Bank and the International Monetary Fund in Washington.
Medicins sans Frontieres Joanne Liu president said the number of cases was accelerating at an alarming rate and more support must be mobilised on the ground within the next three days.
She said every three weeks the number of infected people will double if the same response that is being made in Africa continues.
The BBC reports many countries have now stepped up measures to check people coming in from West African countries for Ebola.
The World Health Organization (WHO) has warned that Ebola is now entrenched in the capital cities of all three worst-affected countries and is accelerating in almost all settings.
WHO deputy head Bruce Aylward warned that the world's response was not keeping up with the disease in Guinea, Liberia and Sierra Leone.
The three countries have appealed for more aid to help fight the disease.
The outbreak has killed more than 3,860 people, mainly in West Africa.
More than 200 health workers are among the victims.
Speaking on Thursday, Mr Aylward said the situation was worse than it was 12 days ago.
"The disease is entrenched in the capitals, 70 percent of the people affected are definitely dying from this disease, and it is accelerating in almost all of the settings," he said.
Meanwhile in Spain, seven more people are being monitored in hospital for Ebola. They include two hairdressers who came into contact with Teresa Romero, a Madrid nurse looked after an Ebola patient who had been repatriated from West Africa.
Australian nurse tests negative to Ebola
A nurse in Cairns has tested negative for the Ebola virus after returning from treating patients in Sierra Leone.
Sue-Ellen Kovack, 56, returned to Australia on the weekend after a month-long stay in Sierra Leone, where she worked with the Red Cross treating patients of the outbreak, the ABC reports.
Sue-Ellen Kovack Photo: AAP
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While she returned home healthy, her temperature rose to 37.6 degrees Celsius on Thursday morning.
She was assessed by an infectious diseases specialist at Cairns Base Hospital, where she works, and underwent blood tests which were sent to Brisbane to be tested for the virus on Thursday.
Her blood has tested negative for the disease, meaning she did not contract the deadly virus while working with infected patients.
Authorities in Australia have confirmed that 11 people have been tested for the Ebola virus but so far the results have all been negative.
This morning, Queensland chief health officer Jeannette Young announced Ms Kovack had been cleared of the deadly virus.
"She still remains in the incubation period so we're going to keep a very, very close eye on her," she said.
"Although her fever resolved this morning she still is a little bit unwell, so we also do want to find out whether she's picked something else up."
Ms Kovack, who has been in quarantine since yesterday afternoon, will remain under observation in hospital for the next 24 hours.
Ms Kovack worked in Kenema, in Sierra Leone's south, in the Red Cross' new Ebola Treatment Centre.
The situation there is overwhelming for the local community. Over 15 health workers had died in the government hospital in Kenema, while many more were infected and the staff were abandoning the hospital.
Before heading over, Ms Kovack was optimistic, saying that rather than focusing on the mortality rate, she preferred to draw attention to the survival statistics.
Spanish nurse deteriorates
Meanwhile, the health of a Spanish nurse who is the first person known to have caught Ebola outside of Africa has worsened.
The hospital in Madrid where Teresa Romero is being treated said her clinical situation has deteriorated, but could not provide any further information due to her wish for privacy.
Ms Romero had helped treat two Spanish missionaries who died after returning from West Africa with Ebola.
She tested positive on Monday, and has publicly said she believes she may have caught the deadly virus by touching her face with an infected glove after cleaning the room of one of the missionaries.
Aircraft cleaners walk off job
Fears are growing in the United States about Ebola with about 200 airline cabin cleaners walking off the job in New York and some lawmakers demanding the government ban travellers from the West African countries hit hardest by the virus.
Cleaners at New York's LaGuardia Airport stopped work in protest over what they say is insufficient protection for workers whose jobs include cleaning up vomit and bathrooms.
The US is to start screening travellers at five major airports, and the government says its intention is to expand airport Ebola screenings internationally to as many different checkpoints as possible.
Britain is also to begin enhanced screening for Ebola in people travelling from affected countries.
But Australia's Health Minister Peter Dutton said its quarantine controls were tight enough without also checking the temperatures of people arriving from West Africa.