Ebola 2 Essay, Research Paper
In 1976, Ebola virus made it s first appearance in Zaire, Africa, causing the death of hundreds of people. The second outbreak occurred western Sudan, also in 1976. These were large outbreaks, resulting in more than 550 cases and 340 deaths. In 1979, Ebola mysteriously re-appeared in Sudan causing 34 cases and 22 fatalities. The most recent Ebola Zaire outbreak started with a surgery on a suspected Malaria patient in Kikwit, Zaire on April 10, 1995. As in the 1976 outbreak, further transmission of the virus in Kikwit occurred though close personal contact with infectious blood and other body fluids. Members of the surgical team then developed symptoms similar to those of a viral hemorrhagic fever disease. The Ebola Zaire in Kikwit spread quickly, but investigation and control of the outbreak come from a combined effort of medical teams from the U.S. Center for disease Control and Prevention (CDC), the World Health Organization, and from other health organizations in Belgium, France, and South Africa. Since July 1, 1995, 233 deaths have been reported among the 293 cases, in Africa (Garrett 195).
Since 1976, researchers have searched for an origin and cure of the virus. Scientist have carried out numerous studies and investigations. Therefore, we now know what the virus is capable of doing, how those infected with the disease can be properly treated , and the need to perform prompt action to isolate the virus before it disperses (Garrett 192).
The Ebola virus is a member of a family of RNA viruses known as filoviruses, which consist of the Marburg virus and four Ebola viruses: Ebola Zaire, Sudan, Reston and Tai are the five different viruses that have been known to cause disease in humans, while Ebola Reston only causes disease in monkeys. Filoviruses, arenaviruses, flaviruses, and bunyaviruses are the viruses responsible for causing viral hemorrhagic fevers. All forms of virus of viral hemorrhagic fever begin with fever and muscle aches. These diseases usually progress until the patient becomes very ill with respiratory problems, severe bleeding, kidney malfunctions, and shock. The viral hemorrhagic fever can cause death (Drucker 29).
Ebola viruses are spread though close personal contact with a person who is very ill with the disease, but it is unlikely to spread by close contact with infected person who shows no symptoms. Usually the wide spread action of the virus takes place among hospital care workers or family members who were aiding an infected person. Ebola can spread by the reuse of hypodermic needles, which occurs frequently in underdeveloped countries like Zaire and Sudan, (MacKenzie 113).
The Ebola virus spreads through the blood and is replicated in organs, including the liver, lymphatic organs, kidneys, ovaries and testes. It attacks the vascular endothelium and the platelets. The resulting symptoms are bleeding, especially in the nose, abdomen, pericardium and vagina. Capillary leakage appears to lead to internal and external bleeding, shock and the acute respiratory disorder seen in fatal cases. Patients basically die of incurable shock. Those with severe illness often have fevers and are delirious. It also affects the mental processes making the patients difficult to control (Drucker 38).
However, the disease is not always fatal. One out of ten people infected, survive the infection. Due to its own characteristics, the Ebola virus itself sometimes dies before killing the person (MacKenzie 108).
The scientists in America have discovered that the Ebola virus has actually entered the United States. It is now known that in 1989, monkeys infected with Ebola Reston were imported to Reston, Virginia from the Philippines. The monkeys died horrible death, leading to autopsies and the discovery of the cause of death. Importation of African Green and rhesus monkeys was immediately stopped. The scariest characteristic about the Ebola Reston was that it was known to have been airborne, and that it was systematically killing the monkeys that had been imported from the Philippines to Reston, Virginia. The 149 workers who came in contact with the monkeys were grateful to find that the newly discovered Ebola Reston was not capable of causing disease in humans. Of the 149 workers, none of the workers became ill but two developed antibodies for the Ebola Reston (Garret 192).
Unlike the Reston, Virginia situation, the outbreaks of 1976 and 1979 left no evidence to what might have been carrying the Ebola before it was passed onto humans. To this date no clues have been uncovered about where the virus hides between outbreaks. Collection of animal specimens is currently underway in Kikwit, but the possible species in tropical Africa are so numerous that a long search is likely to be required (MacKenzie 110).
The Ebola Tai was found on November 24, 1995 by a Swiss researcher in Cote d’Ivoire (Ivory Coast), West Africa. She caught the Ebola Tai from a chimpanzee while carrying out an investigation about deaths among local chimps of the Tai forest. When the investigators examined tissue taken from the dead chimpanzee, they found that the animal’s spleen and liver contained large areas of dead tissue similar to those found in patients who perished from Ebola Zaire and Sudan. Instant investigation of the 4200 square-kilometer reserve of the Tai forest was launched, but to this day no trace of the source of Ebola has been found. The researcher was evacuated to a hospital in Switzerland where she recovered. The dedicated researcher has now returned to Ivory Coast to continue her work (Garret 194).
During most of these outbreaks, field teams of researchers have captured more than 3,000 birds and mammals, including small rodents and several thousand possible insects. Material of these animals are now being processed for virus isolation. Blood samples of an estimated 64 suspected cases have also been confirmed (MacKenzie 111).
Still to this day, the origin of the Ebola remains a mystery. Further, and more frightening, its capacity to be airborne remains unknown. Clearly, research needs to be continued, before another outbreak occurs (Drucker 40).
Drucker, Peter. The Truth about Virii. McGrall-Hill Inc., New York: 1995.
Garret, Michael. Behavior of Pathogens. Prentice Hall, Englewood Cliffs, New Jersey: 1994.
MacKenzie, Timothy. Disease Causing Organisms. North River Press, Inc., New Haven: 1996.