The Worlds Fight Against Microbes Essay Research

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The Worlds Fight Against Microbes Essay, Research Paper The Worlds Fight Against Microbes Many infectious diseases that were nearly eradicated from the industrialized world, and newly emerging diseases are now breaking out all over the world due to the misuse of medicines, such as antibiotics and antivirals, the destruction of our environment, and shortsighted political action and/or inaction. Viral hemorrhagic fevers are a group of diseases caused by viruses from four distinct families of viruses: filoviruses, arenaviruses, flaviviruses, and bunyaviruses. The usual hosts for most of these viruses are rodents or arthropods, and in some viruses, such as the Ebola virus, the natural host is not known. All forms of viral hemorrhagic fever begin with fever and muscle aches, and

depending on the particular virus, the disease can progress until the patient becomes deathly ill with respiratory problems, severe bleeding, kidney problems, and shock. The severity of these diseases can range from a mild illness to death (CDC I). The Ebola virus is a member of a family of RNA (ribonucleic acid) viruses known as filoviruses. When these viruses are magnified several thousand times by an electron microscope they have the appearance of long filaments or threads. Filoviruses can cause hemorrhagic fever in humans and animals, and because of this they are extremely hazardous. Laboratory studies of these viruses must be carried out in special maximum containment facilities, such as the Centers for Disease Control (CDC) in Atlanta, Georgia and the United States Army

Medical Research Institute of Infectious Diseases (USAMRIID), at Fort Detrick in Frederick, Maryland (CDC I,II). The Ebola hemorrhagic fever in humans is a severe, systemic illness caused by infection with Ebola virus. There are four subtypes of Ebola virus (Ebola-Zaire, Ebola-Sudan, Ebola-Ivory Coast, and Ebola-Reston), which are not just variations of a single virus, but four distinct viruses. Three of these subtypes are known to cause disease in humans, and they are the Zaire, Sudan, and Ivory Coast subtypes. Out of all the different viral hemorrhagic fevers known to occur in humans , those caused by filoviruses have been associated with the highest case-fatality rates. These rates can be as high as 90 percent for epidemics of hemorrhagic fever caused by Ebola-Zaire virus. No

vaccine exists to protect from filovirus infection, and no specific treatment is available (CDC II). The symptoms of Ebola hemorrhagic fever begin within 4 to 16 days after infection. The patient develops chills, fever, headaches, muscle aches, and a loss of appetite. As the disease progresses vomiting, diarrhea, abdominal pain, sore throat, and chest pain can occur. The blood fails to clot and patients may bleed from injection sites as well as into the gastrointestinal tract, skin, and internal organs (CDC I). The Ebola virus is spread through close personal contact with a person who is very ill with the disease, such as hospital care workers and family members. Transmisson of the virus can also occur from the reuse of hypodermic needles in the treatment of patients. This

practice is common in developing countries where the health care system is underfinanced (CDC I). Until recently, only three outbreaks of Ebola among people had been reported. The first two outbreaks occurred in 1976. One was in western Sudan, and the other in Zaire. These outbreaks were very large and resulted in more than 550 total cases and 340 deaths. The third outbreak occurred in Sudan in 1979. It was smaller with only 34 cases and 22 deaths. Three additional outbreaks were identified and reported between 1994 and 1996: a large outbreak in Kikwit, Zaire with 316 cases and 244 deaths; and two smaller outbreaks in the Ivory Coast and Gabon. Each one of these outbreaks occurred under the challenging conditions of the developing world. These conditions including a lack of