Ebola Haemorrahagic Fever Pathogen Project
The Ebola Haemorrahagic Fever, or Ebola for short, was first recognized as a virus in 1967. The first breakout that caused the Ebola virus to be recognized was in Zaire with 318 people infected and 280 killed. There are five subtypes of the Ebola virus, but only four of them affect humans. There are the Ebola-Zaire, Ebola-Sudan, Ebola-Ivory Coast and the Ebola-Bundibugyo. The fifth one, the Ebola-Reston, only affects nonhuman primates. The Ebola-Zaire was recognized on August 26, 1976 with a 44 year old schoolteacher as the first reported case. The Ebola-Sudan virus was also recognized in 1976 and was thought to be that same as Ebola-Zaire and it is thought to have broken out in a cotton factory in the Sudan. The Ebola-Ivory Coast was first discovered in 1994 in chimpanzees in the Tia Forest in Africa. On November 24, 2007, the Ebola-Bundibugyo branch was discovered with an approximate total of 116 people infected in the first outbreak and 39 deaths. The Ebola-Reston is the only one of the five subtypes to not affect humans, only nonhuman primates. It first broke out in Reston, Virginia in 1989 among crab eating macaques.
The Ebola virus is also a part of the Filoviridae family, along with Marburg, and contains a lipid envelope and has a single RNA strand. Ebolavirons are approximately 80 nanometers in width and vary in length. They also contain seven structural proteins that are surrounded by the lipid envelope that has an attached glycoprotein. During replication, it goes through translation but during transcription it stops after one or two genes so that on the 3 prime end it is completely transcribed but the 5 prime end is not transcribed and does not possess a 5-cap.
The Ebola-Zaire branch was the first to be recognized and has the highest death rate of 89 percent. The Ebola-Sudan subtype has a death rate of 53 percent, and the Ebola Haemorrhagic Fever virus as a whole having a 68 percent death rate. Since the Ebola virus has not been recognized for a long time, it cannot be said for sure how it is transmitted though it is believed to be zoonotic, meaning that it is transmitted by animals and from contact with the virus, making it spread quickly through family and friends. It also transmits itself nosocomially, where it can transmit quickly through a health care environment, like a hospital. This is especially dangerous in places like Africa, where the Ebola patients are treated without the proper gloves, masks and other protective gear and the needles are sometimes reused without being cleansed from the virus, spreading it quickly. Along with the easy which the Ebola virus spreads, the symptoms that go along with the virus make it difficult for doctors to treat and diagnose.
The symptoms of Ebola are a fever, headache, joint and muscle aches, vomiting, stomach pain, sore throat, diarrhea, weakness and occasionally read eyes, rashes, hiccups, and internal and external bleeding and since these symptoms are not specific to Ebola, it is difficult to clinically diagnose and can often be confused with other viruses. The ELISA testing, short for enzyme-linked immunosorbent assay, and virus isolation are a couple of examples of the types of laboratory testing that can be done to diagnose and Ebola patient. Because of how easily it can be transmitted, it is extremely difficult to treat and there is no approved, official treatment. As of now, there is not standard treatment but usually the patients are given fluids and oxygen, have their blood pressure monitored and other necessary treatment. To prevent transmission and spreading the virus, the doctors use extreme caution and wear head to toe protective gear and isolate the patient. Even though the Ebola virus is common in Africa, there has been no known outbreak in the United States. Another difficulty facing scientists and the treatment for Ebola is that the natural reservoir for the virus unknown. The natural reservoir of a virus is it’s long term host of the virus. Another interesting fact about the Ebola virus is that it does not have a carrier state, which is where the virus is present in the body, but displays no symptoms but can still be spread. The Ebola virus’ incubation period, where the symptoms first start appearing, is not immediate but ranging from 2 to 21 days, making it even more difficult for doctors to successfully diagnose an Ebola patient.
Though there is no official vaccine for the Ebola virus, but US scientists have successfully developed a vaccine that worked on monkeys. They first injected eight monkeys with the vaccine and then later injected them with the Ebola virus. It protected all eight monkeys from Ebola and they remained completely healthy. The scientists are hoping that they will soon be able to make a vaccine that can work on humans.
The Ebola virus is an extremely deadly virus found in poorer countries, such as Africa, that can have up to a 90 percent death rate. Ebola-Zaire was he first of the five branches to be discovered on August 26, 1967 and is the most deadly. Since it was only discovered in 1976, scientists have not developed a complete understanding of the virus, such as it’s natural reservoir. The non-specific symptoms make it difficult to clinically diagnose, though there are laboratory tests that can be done to help diagnose patients. Ebola Haemorrhagic Fever also spreads quickly and easily, especially in hospitals where the proper safety precautions are not taken. Thankfully, scientists and doctors have made a successful vaccination that worked on monkeys and are working on one that will work on humans, hopefully helping decrease the dangerously high death rate and help save many people that may one day become infected.
Works Cited
2. Fast Acting Ebola Vaccine Protects Monkeys. Science Daily (August 7, 2007). http://www.sciencedaily.com/releases/2003/08/030807075759.htm
3. Questions and Answers about Ebola Haemorrhagic Fever. http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/ebola/qa.htm
4. Ebola Virus. John W. King. http://emedicine.medscape.com/article/216288-overview
