Ebola virus: Why isn't there a cure?

Ebola virus: Why isn't there a cure?

Ebola first appeared more than three decades ago, but there is still no cure or specific treatment for the disease, in part because the dangerous nature of the virus makes it difficult to study, experts say.

People with Ebola are treated with only general therapies meant to support the ill patient. They might be given fluids (Ebola patients are frequently dehydrated), or treatments aimed at maintaining blood pressure and oxygen levels, and treating infections if they develop, according to the Centers for Disease Control and Prevention.

So why aren't there more specific treatments for Ebola?

Part of the reason is that Ebola is caused by a virus, rather than bacteria, and researchers in general have had a harder time developing treatments for viral diseases, compared with bacterial diseases, said Derek Gatherer, a bioinformatics researcher at Lancaster University in the United Kingdom who studies virus genetics and evolution.

"Antiviral therapy has lagged behind antibacterial therapy for decades," Gatherer said.

That's because viruses are small molecules that produce only a handful of proteins, so there are fewer "targets" for treatment, Gatherer said. For this same reason, it has been hard to develop a vaccine against Ebola; a person's immune system (which is primed by vaccines) has a small target, Gatherer said.

Ebola viruses also evolve quite quickly, so it's not clear whether a vaccine developed today would protect against future outbreaks, he said. (Ebola viruses belong to a family of viruses called Filoviridae, and there are five known species of Ebola virus.)

And because the virus is so dangerous in some outbreaks, the mortality rate has been as high as 90 percent researchers must work with the virus in special facilities with high-level safety precautions, which limits the number of experiments that can be done.

"There's only a handful of places in the world were you can actually do Ebola experimentation," Gatherer said. Ebola viruses require a "biosafety level 4" laboratory the highest level of protection.

In addition, relatively few people have ever been infected with Ebola, and even fewer have survived, thus making it hard to study the virus in people or examine whether there are certain biological factors that help people survive, Gatherer said.

Ebola first appeared in 1976, in outbreaks in the Democratic Republic of Congo and Sudan. The origin of the virus is not known, but it is thought to reside in bats.

People become infected with Ebola through close contact with infected animals, and the virus spreads person-to-person through contact with bodily fluids, such as blood or secretions, according to WHO. Symptoms include fever, muscle pain and headache, followed by vomiting, diarrhea, rash and, in some cases, internal and external bleeding, WHO says.

The Ebola virus attacks immune cells, and can cause the immune system to run out of control and release a "storm" of inflammatory molecules, which cause tiny blood vessels to burst, Gatherer said. This blood-vessel damage can cause blood pressure to drop, and lead to multiple-organ failure, Gatherer said.

Some potential Ebola treatments show promise in animal models, including compounds that interfere with the way the virus replicates. Other experimental treatments aim to prevent the virus from entering cells, by blocking the proteins on the surface of cells to which the virus binds.

Another therapy in the works involves injecting mice with parts of the virus and using their antibodies to treat infection. In a 2012 study, four monkeys with Ebola survived the infection when they were given a combination of these antibodies one day after infection.

http://www.foxnews.com/health/2014/07/28/ebola-virus-why-isnt-there-cure/

JD said-"It's all about the money!"

I'm afraid you are dead right! If this disease only effected rich old white guys there would already be a vaccine!

The Pasturs and Madame Curie would not recognizes the world today! What would the world be like if Fleming had patented penicillin? People used to practice medicine and study the sciences to help others! Few do anymore!

Amen.Johnray1

inthesticks - I don't think that funding is a issue in this case. Prion diseases present a whole new set of problems that we're nowhere near getting a handle on yet. The discovery that BSE and CJD are caused by prions is a relatively new discovery itself in the grand scheme of things. Nasty little buggers.

CRS, DrPH wrote: Keep your eyes on Chronic Wasting Disease in deer and elk.  Deer and elk don't eat each other's brains that I am aware of....they must be transmitting the infectious prion through saliva, urine etc.

.............Or getting it from some other route we do not know of yet.  Prion diseases have such a long incubation period it can be almost impossible to trace their source.  My guess is eating the remains of shed antlers (a common trait in deer species as it ads back the minerals lost ).  Many herbivores will eat carrion given the chance.  I once had a pet rabbit who would only eat cat food with my pet cats.  Admittedly she thought herself a cat.  With other rabbit appetites, my cats were quite nervous.

jacksdad wrote: I absolutely agree, Chuck - I lived in the UK when BSE first appeared, and despite assurances that it was passed only from mother to calf and would disappear in a generation, it continued to show up in adult cows within herds.

onefluover wrote: My theory and it is probebly way off the mark, but is that prions have been around as long as proteins and life itself and somehow are a part of the building blocks of life or are a product of it. Kind of like a crystal or like pyrite is to iron. They grow but are not alive as we generally know life. They may serve some unknown function and or may be specific to certain species. I do remember reading that many or all of us may have them but in some of us entually they displace or eat away at our brains leading to Alzheimer's and other such ailments. I don't know though. It's a very interesting subject that I want to research everything on soon.

Back when prions were first being identified as the cause of BSE, I remember seeing an animation of a prion coming into contact with it's counterpart, a normal protein. The prion was able to cause the hydrogen bonds that ball up the chain of amino acids into a specific shape (and consequently, a specific protein) to change. The result was the creation of another prion with the same components, but different folds from the original protein. We have enzymes called proteases that break down proteins we no longer need, and they recognize the ones that need to be targeted. If they didn't, our bodies would end up with an overabundance of proteins serving no purpose. As Chuck pointed out, that situation occurs when prions build up as destructive plaques laid down in the brain, because proteases are no longer able to recognize the new shape and "clean" them out.
Chuck - maybe the answer is to tailor proteases to target known prions. Is there any research being done along those lines?
BTW, I have a lot of family down in the south (Dorset, Devon, Hampshire and Gloucestershire) but I was raised in the north. You certainly ended up in a beautiful part of the world

" Who knows? Prion accumulation may be what causes biological aging! "

That was my thought exactly!