Ebola virus disease (EVD), formerly known as Ebola hemorrhagic fever, is a severe, often fatal illness in humans. As of this post, the virus has spread through many African nations, and is the worst Ebola outbreak every recorded. The virus has infected over 1200 people and abuot 60% of these individuals have died from the disease.
Health practitioners have put themselves at great risk caring for those who have become infected. According to the BBC, one hundred health workers have been affected and half of them have died. At least three high-profile physicians in the forefront of care have succumbed to the virus, and three nurses who worked in the same treatment center as one of the physicians, are believed to have died from the virus.
Two Americans working to battle Ebola in Liberia, one a physician, have tested positive for the virus and are undergoing intensive treatment and workers from Doctors without Borders and the Red Cross are “overwhelmed” for the virus that has no cure.
Depending on the type of Ebola virus, up to 90% of those infected can die a rapid and difficult death. The onset of symptoms may be characterized by a sudden spiking fever, headache, joint, muscle, and stomach pain, diarrhea, vomiting, and in some cases, uncontrolled internal and external bleeding. Infected individuals die from failure of multiple organs in the body such as the nervous system, liver, and kidneys.
The disease is characterized by abnormal immune responses in which the Ebola viruses appear to evade attack of immune cells; dramatic immune imbalances occur in response to infection. There is evidence that the immune system responds with a “cytokine” storm during which certain immune cells “dump” large amounts of pro-inflammatory molecules, cytokines, into the body. Other biological compounds are released as well that contribute to the confused immune response.
Additionally, specialized cells produce insufficient amount of anti-viral cytokines, while at the same time, there is a significant increase in death of other types of immune cells. Scientists at the National Institute of Allergy and Infectious Diseases call this “a mixed anti-inflammatory response syndrome (MARS)”, and suggest that this “catastrophic uncontrolled immunological status contributes to the development of fatal hemorrhagic fever”.
Perhaps some of the symptoms that patients experience are due to autoimmune responses against individual classes of lymphocytes. This would account for the loss of certain immune cells, such as CD4 and CD8 cells. If they were available in higher numbers, they might be able to help the body fight the infection.
Many immunological factors contribute to Ebola virus fatalities. It is my contention that if individuals were able to achieve immune homeostasis, immune balance, they would be better equipped to mount controlled inflammatory responses which might help control the course of the disease.