West African leaders and international health organizations have stepped up plans to combat the world's worst outbreak of the deadly Ebola virus, including the launch of a $100 million campaign to combat its spread.
Margaret Chan, the head of the World Health Organization (WHO), described the outbreak as out-of-control at an emergency meeting with the presidents of Guinea, Liberia and Sierra Leone on Friday.
"The outbreak is moving faster than our efforts to control it. If the situation continues to deteriorate, the consequences could be catastrophic in terms of lost lives, but also severe socioeconomic disruption and a high risk of spread to other countries," Chan said at the meeting in Guinea's capital of Conakry, according to wire reports.
So far 729 people in Guinea, Liberia and Sierra Leone have died since the epidemic broke out in February, while 1,323 cases have been reported—both totals have broken previous records.
The WHO has described the scale of the outbreak as "unprecedented". It launched a $100 million campaign on Thursday to fight the virus and is in urgent talks with donors and international agencies to send hundreds more medical and logistical professionals to the countries hit.
The West African epidemic appears to be accelerating, with 122 new cases reported between July 24 and 27 alone, as well as 57 deaths.
Sierra Leone and Liberia declared a state of emergency this week, calling in troops to quarantine victims and conduct house-to-house searches for victims. Both countries have closed all schools.
In the U.K., the government has warned doctors to be vigilant for unexplained illness in patients who had visited West Africa. The country's Immigration Removal Centers have been told to conduct health assessments on people who have been in affected areas within the preceding 21 days.

Meanwhile, a cyclist from Sierra Leone competing in the Commonwealth Games in Glasgow, Scotland, was quarantined for four days while he was tested for Ebola after suffering from a fever. He proved to be free from disease, and went on to compete in a time trial on Friday. However, teammate Mohamed Tholley has now reportedly gone missing and the head of the Sierra Leone team told U.K's "The Telegraph" newspaper he might wish to avoid returning home while it is disease-struck.
A spokeswoman for the Commonwealth Games denied claims the athlete had absconded at a press briefing on Friday morning.
On the other side of the Atlantic, the U.S. warned on Thursday against travelling to the victim-countries, and said the outbreak would take several months to halt. Two Americans—a doctor and an aid worker working in Liberia—have already contracted the virus. One of them is being treated with an experimental vaccine.
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"This is the biggest and most complex Ebola outbreak in history," said Tom Frieden, director of the U.S. Center for Disease Control and Prevention, in a news release on Thursday.
"It will take many months, and it won't be easy, but Ebola can be stopped."
There is no known cure for the viral illness, which kills around 90 percent of suffers and transmitted to people from wild animals and spreads through human-to-human transmission. Victims often suffer a sudden fever, intense weakness, muscle pain, headache and sore throat. This is followed by vomiting, diarrhea, rash, impaired kidney and liver function, and in some cases, both internal and external bleeding.