New York has confirmed the first case of Ebola in the largest city in the US as the EU dramatically ramped up aid to contain the killer epidemic ravaging west Africa.
The EU announcement of one billion euros for the worst-hit countries comes as fears of a spread of the virus grew, with the first confirmed case in Mali, where a two-year-old girl has tested positive.
The World Health Organisation (WHO), which has warned the Ebola crisis in west Africa "remains of great concern", held talks on Thursday on efforts to ensure access to and funding for potential vaccines.
The New York case is a doctor who recently returned from treating Ebola patients in Guinea, the epicentre of the world's worst outbreak of the disease.
Craig Spencer was placed in isolation at Manhattan's Bellevue Hospital Center, officials said.
With health workers in Spain and Texas already having caught Ebola from patients originally infected in west Africa, New York Mayor Bill de Blasio insisted the city was fully prepared to stop the disease in its tracks.
"We want to state at the outset, (this) is no reason for New Yorkers to be alarmed. Ebola is an extremely hard disease to contract," said de Blasio.
New York Governor Andrew Cuomo said city officials had already identified four people believed to have been in contact with the doctor, who worked for the charity Doctors Without Borders, also known by its French acronym MSF.
He said he did not expect a repeat of the situation in Dallas, where hospital staff appeared to have been caught offguard by the arrival of the disease that has killed almost 4,900 people mainly in Guinea, Liberia and Sierra Leone.
"Dallas was caught before they could really prepare. We had the advantage of learning from their experience," Cuomo said.
The announcement of the New York doctor's positive test came just hours after Mali reported its first confirmed case of the disease, the latest country affected.
Malian health ministry spokesman Markatche Daou said the two-year-old girl had travelled to neighbouring Guinea - with her grandmother.
Health authorities have put 43 people who had contact with the toddler and her grandmother under observation, the WHO said.
And in Ivory Coast, up until now Ebola-free, a hunt was going on for a health worker from Guinea who may have fled across the border after taking fright when a patient he treated died.
EU leaders agreed Friday to boost aid to combat Ebola in west Africa by 400 million euros to one billion euros.
"We're in a race against time on Ebola and we must address both the emergency situation and at the same time have a long term response," Commission head Jose Manuel Barroso said Thursday.
African countries have also pledged to send more than 1,000 health workers to the most severely-hit countries.
With almost 10,000 people now infected, African Union chief Nkosazana Dlamini-Zuma said the regional bloc was responding to an urgent need for medical reinforcements.
East African members of the bloc have also pledged to send another 600 health workers, she added.
A lack of skilled medical staff has been one of the major obstacles in the battle against Ebola.
Health workers have paid a heavy price in the fight against the epidemic, with 244 deaths out of 443 cases.
Microsoft co-founder and philanthropist Paul Allen - who has already dipped into his vast personal fortune to help WHO deal with the crisis - said Thursday he was upping his donation to $100 million.
