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Ebola virus can kill 9 out of 10 infected people in just 15-30 Days Dr. Abhay Jere  Ebola haemorrhagic fever (EHF) is one of the most virulent viral diseases known to humankind, causing death in 50-90% of all clinically ill cases. Ebola viruses are a group of exotic viral agents that cause a severe hemorrhagic fever disease in humans and other primates. Very recent (Dec.2006) study conducted in the Republic of Congo confirms that the ebola virus is causing a massive die-off of gorillas and chimpanzees in Africa. Scientists differ on whether there's anything humans can do to help their closest relatives in the animal kingdom. Four years ago, they started to find gorilla carcasses. And over the next four months 130 of the 143 apes disappeared.In 1976, Ebola virus first emerged in simultaneous outbreaks in Sudan and Zaire (now Democratic Republic of the Congo). In total, these two outbreaks resulted in deaths of 340 people out of 550 plus cases that were identified in these two nations.The Ebola virus once again reappeared in 1979 in sudan. No cause was identified and 22 patients of 34 cases died with fatality rate of more than 60%, similiar to 1976 outbreaks. The recent Ebola virus outbreak was centered in Kikwit, Zaire. (Kikwit is a city of 400,000 located 400 kilometers east of Kinshasa, the capital of Zaire.) The outbreak appeared to had started with a patient who had surgery in Kikwit on April, 1995. Members of the surgical team then developed symptoms similar to those of a viral hemorrhagic fever disease. Ebola hemorrhagic fever was suspected by a Belgium physician who reported the disease to the Zairian government. Ebola virus hemorrhagic fever disease in humans begins with an incubation period of 4–10 days, which is followed by abrupt onset of illness. Fever, headache, weakness, and other flulike symptoms lead to a rapid deterioration in the condition of the individual. In severe cases, bleeding and the appearance of small red spots or rashes over the body indicate that the disease has affected the integrity of the circulatory system. Individuals with Ebola virus die as a result of a shock syndrome that usually occurs 6–9 days after the onset of symptoms. This shock is due to the inability to control vascular functions and the massive injury to body tissues. The Ebola virus are RNA viruses. There are four known subtypes or species of Ebola viruses are Zaire, Sudan, Reston, and Côte d'Ivoire (Ivory Coast), named for the geographic locations where these viruses were first determined to cause outbreaks of disease. Ebola viruses are very closely related to, but distinct from, Marburg viruses. Collectively, these pathogenic agents make up a family of viruses known as the Filoviridae. When magnified several thousand times by an electron microscope, these viruses have the appearance of long filaments or threads. Ebola virus is spread through close personal contact with a person who is very ill with the disease. In previous outbreaks, person-to-person spread frequently occurred among hospital care workers or family members who were caring for an ill person infected with Ebola virus. Transmission of the virus has also occurred as a result of hypodermic needles being reused in the treatment of patients. Reusing needles is a common practice in developing countries, such as Zaire and Sudan, where the health care system is underfinanced. Medical facilities in the United States do not reuse needles.
Ebola virus can also be spread from person to person through sexual contact. Close personal contact with persons who are infected but show no signs of active disease is very unlikely to result in infection. Patients who have recovered from an illness caused by Ebola virus do not pose a serious risk for spreading the infection. However, the virus may be present in the genital secretions of such persons for a brief period after their recovery, and therefore it is possible they can spread the virus through sexual contact.
Ebola hemorrhagic fever can be diagnosed by detection of Ebola antigens, antibody, or genetic material, or by culture of the virus from these sources. Diagnostic tests are usually performed on clinical specimens that have been treated to inactivate (kill) the virus. Research on Ebola virus must be done in a special high-containment laboratory to protect scientists working with infected tissues. The virus specifically affects liver cells and reticuloendothelial cells. Affected blood capillaries leak fluids and plasma proteins, causing intravascular coagulation and a zero clotting factor. The water volume loss in the body produces clinical shock, thereby causing the organs of the body to fail. The incubation period is typically from two to twenty-one days, and, depending on the victim, symptoms occur fairly shortly after transmission. "All forms of viral hemorrhagic fever begin with fever and muscle aches. Depending on the particular virus, disease can progress until the patient becomes very ill with respiratory problems, severe bleeding, kidney problems, and shock. With Ebola, persons develop fever, chills, headaches, muscle aches, and loss of appetite. As the disease progresses, vomiting, bloody diarrhea, abdominal pain, sore throat, and chest pain can occur. The blood fails to clot and patients bleed from injection sites as well as into the gastrointestinal tract, skin, and internal organs.". This last phase of the infection is known as the "bleed-out" phase, as the victim will typically bleed from every orifice. Fatality is approximately ninety percent with Ebola Zaire, and sixty percent with Ebola Sudan. No fatality rate has yet been determined for Ebola Tai, as only one known human has been infected--a Swiss scientist who contracted it from a chimpanzee but recovered successfully. As aforementioned, Ebola Reston is believed to be only hazardous to primates, and therefore has no human fatality rate as of yet either.
There is currently no cure or vaccine for any of the Ebola strains. "One of the keys to try to find a cure or vaccine for Ebola is to discover its' natural host. Although extensive research has been done, scientists have no evidence of the natural host of Ebola. Many people are under the misconception that monkeys are the natural host for Ebola. This is highly unlikely since monkeys die of Ebola as quickly as humans."Presently, scientists can only recommend that patients undergo plasma albumin replacement prior to clinical shock, as antisera have yet to be developed. "Although it is believed that death results directly from the damage to internal tissues, it is not known why some patients manage to survive the disease...Convalescence is slow, often taking five weeks or more, and is marked by weight loss and amnesia in the early stages of recovery." Questions regarding immunity from the virus have yet to be answered, as there is no definitive proof of the fact that recovered victims have come into contact with the virus for a "second clinical infection". However, it is assumed that immunity, if it exists, is strain-specific. Nonetheless, scientists are almost certain that reoccurrence is not a factor, as the virus has not yet demonstrated a latency period in its victims. |
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