The Worlds Fight Against Microbes Essay Research — страница 2

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adequate medical supplies and the frequent reuse of needles, played a major part in the spread of the disease. The outbreaks were controlled quickly when appropriate medical supplies were made available and quarantine procedures were used (CDC I). Ebola-Reston, the fourth subtype, was discovered in 1989. The virus was found in monkeys imported from the Philippines to a quarantine facility in Reston, Virginia which is only about ten miles west of Washington, D.C. (Preston 109). The virus was also later detected in monkeys imported from the Philippines into the United States in 1990 and 1996, and in Italy in 1992. Infection caused by this subtype can be fatal in monkeys; however, the only four Ebola-Reston virus infections confirmed in humans did not result in the disease. These

four documented human infections resulted in no clinical illness. Therefore, the Ebola-Reston subtype appears less capable of causing disease in humans than the other three subtypes. Due to a lack of research of the Ebola- Reston subtype there can be no definitive conclusions about its pathogenicity (CDC II). Staphylococcus is a genus of nonmotile, spherical bacteria. Some species are normally found on the skin and in the throat, and certain species can cause severe life-threatening infections, such as staphylococcal pneumonia (Mosby 1477). Despite the age of antibiotics, staph infections remain potentially lethal. By 1982 fewer than 10 percent of all clinical staph cases could be cured with penicillin, which is a dramatic shift from the almost 100 percent penicillin

susceptibility of Staphylococcus in 1952. Most strains of staph became resistant to penicillin?s by changing their DNA structure (Garrett 411). The fight against staph switched from using the mostly ineffective penicillin to using methicillin in the late 1960?s. By the early 1980?s, clinically significant strains of Staphylococcus emerged that were not only resistant to methicillin, but also to its antibiotic cousins, such as naficillin. In May 1982 a newborn baby died at the University of California at San Francisco? s Moffit Hospital. This particular strain was resistant to penicillin?s, cephalosporin?s, and naficillin. The mutant strain infected a nurse at the hospital and three more babies over the next three years. The only way further cases could be prevented was to

aggressively treat the staff and babies with antibiotics to which the bacteria was not resistant, close the infected ward off to new patients, and scrub the entire facility with disinfectants. This was not an isolated case, unfortunately. Outbreaks of resistant bacteria inside hospitals were commonplace by the early 1980?s. The outbreaks were particularly common on wards that housed the most susceptible patients, such as burn victims, premature babies, and intensive care patients. Outbreaks of methicillin resistant Staphylococcus aureus (MRSA) increased in size and frequency worldwide throughout the 1980?s (Garrett 412). By 1990, super-strains of staph that were resistant to a huge number of drugs existed naturally. For example, an Australian patient was infected with a strain

that was resistant to cadmium, penicillin, karamycin, neomycin, streptomycin, tetracycline, and trimethoprim. Since each of these drugs operated biomechanically the same as a host of related drugs the Australian staph was resistant, to varying degrees, some thirty-one different drugs (Garrett 413). A team of researchers from the New York City Health Department, using genetic fingerprinting techniques, traced back in time over 470 MRSA strains. They discovered that all of the MRSA bacteria descended from a strain that first emerged in Cairo, Egypt in 1961, and by the end of that decade the strain?s descendants could be found in New York, New Jersey, Dublin, Geneva, Copenhagen, London, Kampala, Ontario, Halifax, Winnipeg, and Saskatoon. Another decade later they could be found

world wide (Garrett 414). New strains of bacteria were emerging everywhere in the world by the late 1980?s, and their rates of emergence accelerated every year. In the U.S. alone, an estimated $200 million a year was spent on medical bills because of the need to use more exotic and expensive antibiotics, and longer hospitalization for everything from strep throat to life-threatening bacterial pneumonia. These trend, by the 90?s, had reached the level of universal, across- the-board threats to humans of all ages, social classes, and geographic locations (Garrett 414). Jim Henson, famed puppeteer and inventor of the muppets, died in 1990 of a common, and supposedly curable bacterial infection. A new mutant strain of Streptococcus struck that was resistant to penicillin?s and