On Friday, the Geneva-based World Health Organization (WHO), the UN's health body, announced that 4,033 deaths had been confirmed in the current Ebola outbreak. The epidemic began in West Africa at the start of the year.

There have been a total of 8,300 registered cases in seven countries. Those countries have been divided up into two groups by the WHO. The first includes Guinea, Liberia and Sierra Leone - by far the worst affected.

Liberia has seen 4,076 cases and 2,316 deaths, followed by Sierra Leone with 2,950 cases and 930 deaths. Guinea, where the epidemic originated, has seen 1,350 cases and 778 deaths.

The second group of countries includes Nigeria, Senegal, Spain and the United States, which have seen a small number of highly isolated cases.

A separate strain of Ebola has been seen in the Democratic Republic of Congo, with 43 deaths up until October 7.

David Nabarro, the senior UN coordinator for the international response to Ebola, said the number of cases was probably doubling every three-to-four weeks.

Nabarro told the UN General Assembly on Friday that, without a global response,"the world will have to live with Ebola forever." He said the international effort needed to be 20 times greater than it is currently.

African trial of Ebola vaccine begins

The first African Ebola vaccine trial began on Friday, the WHO also announced. Three people in Mali were injected with an experimental vaccine - they are among 40 health workers there who volunteered to participate in a trial of the cAd3-EBO-Z vaccine.

The vaccine was developed by the US National Institute of Allergy and Infectious Diseases. Initial trials of the vaccine started in September on healthy people in the UK and US. Forty others will take part in Gambia.

The trial vaccine was found to stimulate an immune response against the virus in chimpanzees.

A trial for a second vaccine developed by Canada's health agency is being conducted in the US.

Macedonia backtracks on Ebola warning

On Friday, Macedonia's Health Ministry expressed doubt that a Briton who died Thursday had Ebola. Officials cautioned, however, that an official diagnosis would not come before the weekend.

The ministry had earlier announced that it believed the man had the virus because of his "serious health condition" when admitted to hospital.

Meanwhile, a Spanish nurse diagnosed as the first person to have caught Ebola on European soil remains in serious condition after respiratory failure. Officials have quarantined her and 14 others in Madrid.

Ebola likened to AIDS outbreak

On Thursday, the top US medical official said the Ebola outbreak in West Africa was the biggest public health challenge since the emergence of HIV/AIDS.

Thomas Frieden, the director of the US Centers for Disease Control and Prevention, told a donor conference in Washington DC that more immediate action must be taken.

"In the 30 years I've been working in public health, the only thing like this has been AIDS, and we have to work now so that this is not the world's next AIDS," he said.

"Speed is the most important variable here. This is controllable, and this was preventable. It's preventable by investing in core public health services, both in the epicenter or most affected countries, in the surrounding countries and in other countries that might be affected."

jr/mkg (dpa, AFP, Reuters, AP)