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Ebola explained by MCCC Biology professors

MCCC Biology professor Maris Fonseca explains how the Ebola virus is transmitted.

The Ebola epidemic has been misrepresented by the media, according to MCCC Biology professors Maris Fonseca and Philip Wahr.
MCCC President Kojo Quartey began an Oct. 27 forum by expressing his frustration with the use of the term “West Africa” when referring to the countries effected by the Ebola virus.
He emphasized that three countries have most of the Ebola cases out of the fifteen that make up the region.
“I called my travel agent just two weeks ago, and I said, ‘I want to take a trip to Ghana, I want to go down and see my mom for Christmas,’ Quartey said.
“She said, ‘Why would you want to do that with all of this Ebola?’ ”
Quartey said there is not a single case of Ebola in Ghana, where he was raised and his family still lives.
“Stop demonizing those West Africans,” he said.
Fonseca explained the basic science of the Ebola Virus Disease (EVD). She walked through the main properties of viruses, what they are, and how they spread.
She said viruses are everywhere in the world.
“The vast majority have very little effect on our well-being and health,” she said.
Viruses are like sidecars on a motorcycle, dependent on the main mode of transportation to function, Fonseca suggested. A virus needs a cell to propagate; it’s unable to survive without life.
“Viruses infect all living things,” she explained.
Different categories of viruses infect bacteria, animals (capable of crossing species, like Ebola did), fungus, and plants, she said.
Ebola is believed to come from bushmeat handling and consumption, including the meat of fruit bats. The disease spreads within impoverished communities where food consumption of this type is taking place.
It then can be transmitted to social workers coming to aid the victims. This has been the case for most of the patients receiving treatment in the U.S.
A virus’s ability to infect an individual is like a lock and key system, Fonseca said. Contraction depends on the immune system and the body’s ability to defend against it.
There are a several ways that viruses are spread, Fonseca said: direct contact, droplet transmission, contaminated food or water, or the bite of an insect.
Ebola, however, is not transmitted via insect bites, water or food contaminated with the virus, or through the air.
However, airborne should not be confused with close proximity, Fonseca said. That is considered to be within three feet around an infected person, where coughing or sneezing can expel the virus into the air and spread to those near.
The Ebola virus itself can survive on surfaces for several hours or days in something like blood, she said. An infected person’s body fluids are capable of transmitting the virus to others, but only once symptoms have already begun showing.
“Most of the time we don’t notice when we touch our faces, but that can happen,” Fonseca said.
If a cut on your skin was exposed to the skin of an infected person, there is a chance the sweat on their skin can transmit the virus through the person’s cut. This applies to even micro cuts, which may not be as easily noticed, she said.
Bedding and living spaces of people who are infected can be contaminated and are quarantined and cleaned.
Like many viruses, EVD can be spread more quickly when symptoms get worse.
“The more sick you are, the more you are contagious,” Fonseca said.
EVD is not contagious during the incubation period, she said.
“You need to have had some close contact with an Ebola virus disease patient, and that means that they’re showing symptoms.”
Fonseca explained that organizations are working with local authorities and health care personal to establish isolation and treatment wards. The lack of facilities has been one of the main factors in its spread, because some patients have been turned away because there is no room for them.
She said several groups are involved, including Doctors without Borders, the CDC, the World Health Organization, and the Global Outbreak Alert & Response Network.
In his part of the discussion, Wahr shed light on what the virus itself is like, and how the symptoms effect those who have contracted EVD.
Wahr said the Ebola virus causes a hemorrhagic fever, which is why you see external bleeding associated with the disease. Ebola is one of several hemorrhagic fevers that are virally induced.
The problem with Ebola, he said, is that unlike most similar viruses, patients often do not recover.
There are five different strains of the Ebola virus seen in humans; the deadliest and most common is the Zaire strain, he said.
Wahr explained that blood tests, which directly confirm the existence of the virus within the body, are used to diagnose Ebola.
The Ebola virus disease is extremely rare, is hard to get, and can be contained, Wahr said.
There are a number of signs and symptoms that will appear if you’ve been exposed to the virus. Its incubation period is twenty-one days, but you may show symptoms from two days to two weeks after exposure.
Exposed individuals are not contagious until a fever begins, which in order to be considered for Ebola must be above 101.5 degrees,.
“Once you start showing symptoms, you show a lot of symptoms rapidly,” he said.
In addition to fever, accompanying symptoms effect your GI tract, such as stomach and muscle pains, which are common virus symptoms. This makes it difficult to tell whether someone has Ebola or common influenza.
A less common symptom of EVD is small bruises, which look like small red pinpricks or rashes on the skin, because of blood vessels’ inability to keep blood inside the vein. This can lead to flaking of skin on the bruised sites.
Most bleeding, however, occurs within the GI tract, so bloody stools or vomit is the most common.
People do sometimes suffer bleeding from nearly any mucus membrane surface, such as the eyes, ears or nose, late into the progression of the disease.
“Typically six to 16 days after symptoms is when death occurs. If you’re going to get better, you’re going to get better in about this same time frame,” Wahr said.
The virus itself does not cause death directly, he said. Rather, death is caused by the extreme drop in blood pressure and subsequent state of shock the body will go into. Ebola targets the body’s immune system, much like typhoid and other illnesses.
“It’s not actually the virus itself that is killing you, it’s your body’s response to the virus that is actually causing the death,” Wahr said.
The body’s own defense becomes over-stimulated, causing the immune system to basically kill you, he said.
Wahr explained the various functions of white blood cells and the way they attack anything that is not supposed to be inside of you. He mentioned antibodies that the immune system can create that target the virus, which is why survivors of the disease can donate their blood to patients battling EVD.
In closing, Wahr mentioned vaccines that are being developed. They are in different stages of development, but none are ready for human trials.
The two professors also took questions from the audience. Adjunct professor Margie Bacarella asked about the success rate of blood transfusions and experimental drugs such as ZMapp, which focuses on antibodies made in the bodies of survivors of the disease.
Wahr said there is not enough data at this point to know. He explained the disease is rare, so it will take time for these studies to start drawing conclusions.
“Once you’ve had the disease, you start making those antibodies to it, so somebody who recovered from it should still have those antibodies – antibodies we know are still in these patients for at least ten years,” he said.
Fonseca reminded the audience that other viruses are more of a problem in the U.S. than Ebola.
“You are way more likely to get the flu than Ebola, so get your flu shots!” she said.
After the panel discussion, Fonseca said the Ebola crisis isn’t likely to disappear.
“It’s hard to predict. I don’t think the outbreak is going to end any time soon, unfortunately.”
Wahr blamed the media for the general public’s lack of knowledge of Ebola.
“There’s a lot of misinformation being propagated out there by the media. The media is not helping,” he said.
He said it’s unlikely that Ebola will become a serious problem in the U.S.
“Sure, there’s going to be a few, but they’re not going to spread any more than the last one did. And frankly, the only reason the last one did is because one hospital in Texas was not prepared. I don’t think at the next hospital that’s going to be an issue.
“It’s easily contained if you know what you’re doing.”