Two Americans were recently cured of the deadly Ebola virus that is sweeping across west Africa. Now the physicians who thought up the so-called miraculous cure have released details on how it works and what inspired it.

Doctor Kent Brantly and missionary Nancy Writebol were both working at a hospital in Liberia when it was suspected that they had contracted the same deadly Ebola virus that has killed 961 people and caused 1,779 infections as of Aug. 6, according to the World Health Organization (WHO).

Back in April, the WHO and Medecins Sans Frontieres (MSF), which are fronting the international emergency response against this Ebola outbreak, expressed their suspicion that the worst was over, with containment of the outbreak proving relatively successful and the rate of infection having slowed.

However, by June the outbreak had surged again, with the country of Sierra Leone declaring a state of emergency as international and local health organizations scrambled to contain the disease.

By the time Brantly and Writebol became infected, Liberia had become the next major victim of the surge. Even affter spreading from Guinea to its neighboring countries, Ebola cases in Liberia had been reported in relatively containable numbers. That all changed in the wake of the surge; Liberia now reports 554 cases of Ebola infection - more cases than Guinea.

"Miracle" Means Taking a Shower

Before the missionaries were rushed back to America, they were administered a "highly experimental" treatment, according to a paper recently released in the journal Annals of Internal Medicine.

What's remarkable is that within hours of receiving this treatment, Brantly - who had been found in the poorest condition and largely unresponsive to other treatments - "was able to take a shower on his own."

According to the WHO, Ebola has a fatality rate of 50 percent, and is characterized by an abrupt onset of fever and intense weakness and muscle pain. The act of simply taking a shower would prove too much for patients even in the early onset of an Ebola infection. (Scroll to read on...)

Knowing this, Brantly had reportedly called his wife to say his final farewells while he still had the strength. Thankfully, he has since been given the opportunity to say some new "hello's."

So just what was Brantly given? According to Scott Podolsky, who wrote the Annals paper, both the "miraculously cured" patients were treated with something that mirrors "passive serotherapy" - a strategy that was developed long ago.

"This is not the first time that passive serotherapy has been described as 'miraculous,'" Podolsky writes. "These headlines hearken back to well over a century ago, decades before the advent of such miracle drugs as sulfonamides and antibiotics."

Mice to the Rescue

According to the paper, the treatment, called ZMapp, is a three-mouse monoclonal antibody. This essentially means that it was made with antibodies specially designed in the blood of mice after they were exposed to fragments of the Ebola virus.

This strategy was reportedly first developed to help protect laboratory animals from common toxins released by diphtheria and tetanus, but researchers eventually realized they could apply it to humans as well.

"From the 1890s onward, this model of production - expose an animal (guinea pig, rabbit, cow, horse, etc.) to an identified microbial pathogen, generate antibodies ... and then 'passively' transfer the pre-formed antibodies to an exposed animal or person - could be expanded to such feared and prevalent diseases as pneumococcal pneumonia and meningococcal meningitis," Podolsky explained.

ZMapp is a modernized take on that same strategy, with better understanding of viral strains and immunotherapy helping the process and encouraging the human immune system to accept these mousey antibodies. (Scroll to read on...)

The Final Option

Since Writebol and Brantly have had their lives saved by the experimental treatment, a WHO discussion panel determined only yesterday that "it is ethical to offer unproven interventions with as yet unknown efficacy and adverse effects, as potential treatment or prevention."

And that's just what ZMapp was before this panicked use of the drug. Prior to Brantly and Writebol's cases, the drug had only been tested on animals, namely monkeys. Still, it had been proven very effective in those trials, and those are the same kind of results the WHO is looking for to treat "final option" cases.

The WHO has also recently announced a new $100 million response plan that will combine international efforts to solve the Ebola problem. It demands full transparency and the sharing of data between professionals and governments.

"The scale of the Ebola outbreak, and the persistent threat it poses, requires WHO and Guinea, Liberia and Sierra Leone to take the response to a new level, and this will require increased resources, in-country medical expertise, regional preparedness and coordination," said Margaret Chan, WHO's Director General. "The countries have identified what they need, and WHO is reaching out to the international community to drive the response plan forward." (Scroll to read on...)

It stands to reason that the results of "final option" experimental treatments such as ZMapp would be included in this international exchange of information.

However, Podolsky does warn that ZMapp and therapies like it aren't always as remarkably effective as these recent results suggest. The effectiveness of the drug can be highly reliant on the strain of the disease, and it certainly shouldn't be seen as an end-all to the Ebola problem.

"There is only so much we can ask of seemingly magic bullets alone," he said.

 ZMapp is also still very much in developmental stages, and was only offered to the missionaries on compassionate grounds by the drug's manufacturer.

In that sense, it is not unreasonable to wonder who would deserve such a "final option" in the first place. There certainly aren't enough experimental treatments to go around, so who determines who gets a last chance at living?

These are questions that still need to be answered, but Podolsky remains fairly optimistic about the future.

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