[Feature] Ebola for Dummies

The Virus

The ongoing Ebola virus epidemic in West Africa, with a 70% fatality rate and an estimated sum of 13,000 deaths, has raised grim attention worldwide and has called for immediate public and government response. This section will attempt to unravel the identity of this virus and any available cure for this deadly disease.

The Ebola virus causes fatal hemorrhagic fever whereby victims bleed internally and externally at the peak of infection. Due to the extreme severity of the syndrome, victims have a very high risk of death. Initial signs include fatigue, fever, and muscle pain just like any ordinary flu symptoms. The syndromes then extend to headaches, abdominal pain, and chest pain. A week later, infected victims are ravaged by vomiting, coughing of blood, and severe bloody diarrhea. Death comes usually after one to two weeks due to low blood pressure and loss of bodily fluids. Yet the very lucky may survive, but only by passing through this critical period.

▲ The Ebola virus causes fatal hemorrhagic fever

The menacing Ebola virus is actually a string of benign biomolecules and ribonucleic acid (RNA). The string-like appearance indicates that the virus belongs to the Filoviridae family, which is very effective at reproducing in living cells. The virus’ main target of infection is the lining of blood vessels, called endothelial cells, and types of white blood cells, specifically monocytes and macrophages. Its destruction of blood vessel lining causes widespread hemorrhaging and wreaks havoc on the human body. To make matters worse, the Ebola virus also interferes with the human immune system, preventing effective cellular response to the virus.

The virus can be transmitted between humans through direct contact with the bodily fluids, such as blood and mucus, of infected people. It is suspected that the virus can be transmitted over very long distances through bats. It is suspected that bats can contract the disease without being affected and cause animal-to-human Ebola virus transmission. Health experts say that the combination of bad health infrastructure and the spread of the virus to a previously unaffected region is a main reason behind the massive death tolls in West Africa.

The Cure

Despite the horrific events caused by the Ebola virus, there is hope. An experimental drug called ZMapp has been developed by pharmaceutical researchers to cure this disease. The drug has been subject to intense scrutiny by the media and health specialists during the course of the Ebola outbreak. Kent Brantly, an American doctor who volunteered for healthcare work in West Africa and later on contracted the disease, was the first to be cured with the experimental vaccine. ZMapp is the only available “silver bullet” drug capable of curing Ebola. Yet the worldwide supply of vaccine has been exhausted after being administered to only 7 patients.

The ZMapp magic comes from neutralizing antibodies that can provide passive immunity against Ebola virus. Analogous to a lock and key, the Ebola-targeted antibody is designed to grab and neutralize the virus that causes the symptoms within the patient’s blood system. The additional antibody boost is critical to curing Ebola victims, as the natural immune system cannot produce enough antibodies to defend itself from the virus. This strategy is an extension of another experimental treatment conducted in the last 1995 Congo Ebola outbreak, where Ebola antibodies containing whole blood from recovering patients were administered to ailing patients.

The first steps of research were conducted and funded by the United States Army Medical Research Institute of Infectious Diseases (USAMRIID) in 2013. In the initial experimental studies, scientists administered Ebola-fighting antibodies to groups of monkeys. Six out of six survived when the drug was injected one hour after infection, while four out of six survived when the drug was administered two days after infection. The findings were no secret at all. The studies were published openly in the high-profile scientific journal Science Translational Medicine.

Thanks to the initial scientific studies, the drug was eventually produced by biotech companies. The ZMapp vaccine is a cocktail of antibodies created by Leaf Biopharmaceutical, a biotech company based in San Diego and Defyrus Inc, a Toronto biodefence company. The only viable production method so far is artificially growing antibodies with deoxyribonucleic acid (DNA) recombinant tobacco plants. However, despite the onslaught of dying patients in West Africa, only a limited supply of the drug can be produced with these genetically modified plants.

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