Stewed: Ebola

By Megan Jo
Segment Producer

This is Megan Jo with Other Side Drive’s “Stewed,” your source for all things science. The Ebola virus. We have all heard about it, but how much do we really know? A recent poll conducted by the Harvard School of Public Health found that four in ten adults in the U.S. are concerned that there will be a large outbreak in the U.S. 26% believe that they or someone in their immediate family may become infected with the deadly disease.

And 68% of those surveyed believe that the virus spreads very or somewhat easily. However, experts on the virus, including the “CDC” and the “WHO” report that the virus is not an airborne illness and is transmissible only through direct contact with infected bodily fluids, objects or animals. I had the privilege of speaking about the virus with Dr. Kelly Woytek, professor of virology, here at Texas State.

“The thing that I think people need to know about Ebola is that its not highly transmissible. It takes a lot to get the virus, but if you are in direct contact with bodily fluids, you’re chances of getting [it] are higher, but if you’re not, it’s not an aerosol transmission. You have to have direct contact.”

— Dr. Kelly Woytek

I decided to do some research of my own, and as I learned more about this virus, I became less frightened for my own safety. First off, there has never been a single case of infection in the U.S. and the current African outbreak is limited to five countries: Guinea, Liberia, Nigeria, Sierra Leone and now Senegal. [Editor Note: The CDC confirmed the first case of Ebola in the U.S. on Sept. 30 in a man who had traveled to Dallas from Liberia. The man died on Oct. 8. Two other cases have been confirmed in the U.S.]

“We’re pretty safe here in the U.S. You don’t need to be worried about contracting Ebola virus, but I think it’s great to educate yourself and to be able to see the segments on the news and be able to evaluate it on whether it’s a concern or not a concern.”

Symptoms may appear anywhere from two-to-21 days after exposure to the virus, although eight-to-10 days is most common. According to the WHO, symptoms of the virus typically include the sudden onset of 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, the creepiest symptom of all, both internal and external bleeding, also known as hemorrhagic fever. The final stage of the deadly disease is bleeding. Once the virus has severely damaged the liver, clotting factors are thrown out of whack and the victim often bleeds to death. A truly awful way to die. As of August 28, the CDC reported 3,069 suspected and confirmed cases and of those 1552 had died. That’s about a 51% fatality rate. While this is the largest outbreak ever reported, past outbreaks have had fatality rates as high as 90%.

One-third of those polled in the recent Harvard study believe there is an effective medicine to treat people infected with the virus. Currently, there is no proven medication or vaccination that exists, and the recommendations for treatment includes maintaining fluids and electrolytes, monitoring oxygen saturation and blood pressure and treating any other co-infections. There are many experimental treatments and vaccines in the works, but they are all in early trial periods and have only been used prematurely because of the recent outbreak. There is one vaccine currently in its human trial phase, after having much success in monkeys, but the treatment that has received the most publicity is the experimental biopharmaceutical drug known as “ZMapp.” This is the drug that was given to the two American medical aid workers that were brought back from Africa after being infected with the virus. Both of the workers treated with the drug recovered and have since been released from the hospital.

One Canadian study acquired 21 monkeys and injected them each with a lethal dose of the virus. Of the 21 monkeys, they gave 18 of them ZMapp. All of the monkeys that received the treatment survived the virus and the three that were infected but didn’t receive Zmapp all died. Unfortunately, the supply of this drug has been exhausted so it could take months before more can be produced. Zmapp is produced through a very interesting process known as “pharming.”

Quick biology refresher: when a virus or other infectious microbe attacks a person that person has an immune response and attempts to create antibodies. Antibodies are what keep the virus busy so that it can’t attack any more human cells. Each virus has a specific antibody that will attack it. If the body can’t produce these antibodies quickly enough to keep up with the virus, the virus wins. So, it’s the antibodies we are after.

Now, back to this experimental treatment and the process by which ZMapp is produced. First, mice were injected with the virus and then antibodies were taken from their spleens. The gene coding for the best antibody was extracted and humanized. This process doesn’t yield adequate amounts of antibodies. So, to obtain these antibodies on a large enough scale, the virus is injected into a tobacco plant similar to the tobacco plant that produces cigarette tobacco. After these plants grow, their leaves, which are full of antibodies, are ground up and processed to make the drug. While this treatment is promising, it will take some time before it can be used in the current outbreak because these plants take time to grow.

While the damage done in West Africa as a result of this outbreak is truly devastating, our chances of becoming infected in the U.S. are rather non-existent. Dr. Woytek agrees.

“I think we’re safe here at Texas State,” Woytek said.