The Science Behind Ebola


Lexi Weyrick

Staff Writer

In March of this year, Ebola began spreading in Guinea.  Since then, the outbreak has quickly become the world’s deadliest Ebola outbreak in history and is still spreading in West Africa.

There have been cases reported in four countries at this point: Guinea, Sierra Leone, Liberia, and Nigeria.  There was one reported incident of a man dying in a hospital in Saudi Arabia of Ebola after having traveled from West Africa.

Current numbers by the World Health Organization cite the number of those who have died from Ebola at 1229, with 2240 total cases, indicating that the outbreak is worsening, with 15 cases and 4 deaths in Nigeria alone. However, Tom Frieden, the director of the CDC, has stated that the data collected is not as accurate as would be preferred.  As well, there is no real way to know whether those numbers should be higher or lower.

Meanwhile, the two American health workers who were transported back to the United States for treatment for Ebola are both recovering steadily.  Several people have been tested for Ebola in the US, but so far every completed test has come back negative.

Furthermore, should Ebola spread to the US, the CDC is both ready to and capable of quarantining infected or possibly infected individuals, so the virus would be very quickly contained.

As the situation in West Africa becomes even more dire, though, and many people are wondering what exactly Ebola is.

Ebola was first discovered in 1976 in Zaire (now the Democratic Republic of the Congo) in Africa.  Since then, the virus has popped up in Uganda, Sudan, the Ivory Coast, Gabon, and the Republic of the Congo.

Even the most deadly outbreak prior to the current one in West Africa had less than 300 deaths.  There have also been cases of Ebola that were caused by laboratory accidents that occurred while scientists were studying the virus.  So far, there have been no natural cases in the United States, though two doctors with the NGO Samaritan’s Purse were flown to Atlanta for treatment.

There are four different known strains of the Ebola outbreak: Ebola-Ivory Coast, Ebola-Sudan, Ebola-Zaire, and Ebola-Reston.  However, the last strain does not appear to cause disease in humans, since several people became infected with the strain but did not become sick.

Once Ebola has entered the body, it will take over the cells that travel the body in order to maintain immunity to external threats.  While it does this, the virus multiplies incredibly fast.  It then tackles the next stage of the immune system, taking over the dendritic cells that help produce a targeted immune response by sending out specific antigens to the areas in need.  Instead of producing antibodies at this point, lymphocytes collectively die.

What scientists refer to as a “cytokine storm” breaks out to create a response in other parts of the immune system.  During the “storm,” a person will develop a high fever and general flu-like symptoms.  However, the Ebola virus does not seem affected by this immune response.

The next step for the virus is to infiltrate the blood system and work its way to the organs.  Cells that make up capillaries contort and leave holes in the blood stream walls.  The virus is able to get inside the blood stream and spread to the different organs.

The organ it focuses on first is the adrenal cortex, because it is able to make blood pressure drop, contributing to decreased bodily defense.

Finally, the body loses control over its bleeding.  Once Ebola makes its way to the liver, the liver’s output of clotting factors goes haywire.  The body starts converting prothrombin into thrombin resulting in excessive clotting.  Because of this, the blood supply slowly stops making its way to organs and the organs begin to fail.  The body hemorrhages as the blood vessels break and there is no longer anything containing what’s left of the non-clotted blood supply.

From a vaccine developing standpoint, it is important to study other viruses that behave like Ebola.  Ebola is able to avoid the immune system and scientists can study other viruses that are able to skirt around bodily responses in order to pinpoint what it is exactly the Ebola does.  From there, scientists can figure out how to make Ebola weaker and create a viable vaccination option for those infected.