Ebola is spreading at a "terrifying rate," with five people infected with the deadly virus every hour in Sierra Leone alone, according to data published Thursday by human rights organization Save the Children.
The London-based group estimates the rate of infected persons in the West African country will increase to 10 every hour if nothing is done to curb Ebola’s spread.
"The scale of the Ebola epidemic is devastating and growing every day, with five people infected every hour in Sierra Leone last week," Justin Forsyth, chief executive of Save the Children, said in a statement. "We need a coordinated international response that ensures treatment centers are built and staffed immediately."
The organization’s infection-rate figures are based on both confirmed cases and an estimate of how many cases are not being reported.
Save the Children’s urgent plea for a more concerted effort to tackle the virus came as Britain hosted an international conference titled "Defeating Ebola: Sierra Leone" in London on Thursday where officials announced plans to build up to 1,000 makeshift clinics in the African nation.
The new clinics will offer little, if any, treatment, but they will get sick people out of their homes, away from their families and hopefully slow the infection rate. Only a fraction of Ebola patients in Sierra Leone are now in treatment centers.
"If we don't do anything, we'll just be watching people die," said Dr. Margaret Harris, spokeswoman for the World Health Organization.
While Ebola continues to ravage West Africa, Sierra Leone is one of the hardest-hit countries. The virus has killed more than 3,300 people and infected at least twice as many in West Africa.
Experts say the virus will continue to spread rapidly unless authorities can reach and isolate at least 70 percent of infected persons. Dozens of Ebola treatment centers have been promised, but they could take weeks or even months to be constructed.
The makeshift clinics, however, could be put up in as little as a week's time, said Manuel Fontaine, the West Africa regional director for the U.N. Children's Fund, which is preparing to help equip them.
"It's not one or the other," said Fontaine. "What we're saying is the care centers need to move fast, but that shouldn't be an excuse to slow down the ETUs (Ebola Treatment Units)."
Experts are turning to these imperfect solutions because the scale of the Ebola outbreak is overwhelming the traditional response methods tried so far.
"We need to try different things because of the scale of this outbreak," said Brice de la Vingne, director of operations for Médecins Sans Frontières.
"We've used these kinds of basic tents in past catastrophes but never for Ebola," he said. "But right now we're screaming for more isolation centers so patients don't infect their communities."
An American freelance cameraman working for NBC News in Liberia has tested positive for Ebola and will be flown back to the U.S. for treatment, according to NBC News.com
Ashoka Mukpo, 33, the freelancers, was hired Tuesday to be a second cameraman for Dr. Nancy Snyderman, the chief medical editor and correspondent who is with three other NBC News employees on assignment in Monrovia, reporting on the Ebola outbreak.
Mukpo came down with symptoms on Wednesday, feeling tired and achy and running a slight fever. He immediately quarantined himself and sought medical advice. On Thursday morning, Mukpo went to a Medecins Sans Frontieres (MSF) treatment center to be tested for the virus. The positive result came back just under 12 hours later.
Snyderman said she believed his exposure to the virus happened sometime before he started working with the NBC crew, since it is usually eight to 10 days before the first symptoms are seen.
"He's ready to get home — of course, appropriately concerned," she said. "But he will be airlifted out soon."
Mukpo is the fifth American infected with Ebola and evacuated from West Africa. He has been working in Liberia on various projects for the past three years.
"The doctors are optimistic about his prognosis," Mukpo's father, Mitchell Levy, said in a message to family and friends. Levy said his son, who also is a writer, "has been engaged with human rights work in West Africa for the last several years. When the Ebola outbreak occurred he felt compelled to return to Liberia to help shed light on how the crisis was being handled socially and politically."
Al Jazeera and wire services