The World Health Organization says the death toll from the Ebola outbreak has risen to more than 4,000 people.
The U.N. agency said Friday that nearly 8,400 cases of the diseases have been recorded in seven countries, with 4,033 people dying from the epidemic. It said all but nine of the deaths were in the three worst affected countries - Liberia, Sierra Leone and Guinea. Eight people died in Nigeria and one patient died in the United States.
The data also includes one Ebola case each in Spain and Senegal, but no deaths in those countries. A separate Ebola outbreak in the Democratic Republic of Congo has killed 43 people.
Also Friday, the United Nations said that it has received only a quarter of its appeal of $1 billion to respond to the outbreak. U.N. Deputy Secretary General Jan Eliasson said more money must be raised.
"Over $20 million has been raised for the multi-partner trust fund in the last week. But we need more. We need much more. Of the $1 billion sought by U.N. agencies under OCHA's consolidated appeal, only one quarter has been funded," said Eliasson.
The U.N. ambassador to the United Nations, Samantha Power, urged more countries to "step up" and donate money. She told a meeting of the U.N. General Assembly that only 24 countries have pledged $1 million or more.
The United Nation's special envoy on Ebola, David Nabarro, told a meeting of the U.N. General Assembly that the outbreak is the worst he has dealt with because it has moved into cities and is affecting a wide region.
"I've worked as a public health doctor for 35 years and I've been involved in many disease outbreaks and indeed some pandemics, but I've never encountered a challenge like this one in my professional life," said Nebarro.
"The reason is that this outbreak has moved out of rural areas and has come in to towns and cities. It's no longer just affecting a very defined geographical location. It's affecting a whole region and it's now also impacting on the whole world," he said.
In another development Friday, U.S. lawmakers agreed to use $750 million in military funds to fight Ebola in West Africa.
Also Friday, a plane was briefly quarantined at a Las Vegas airport while health officials evaluated a sick passenger suspected of having Ebola. Authorities later said the passenger was not infected with the disease.
The virus that causes Ebola spreads only through direct contact with the bodily fluids of an infected person who is showing symptoms.