Discovering the Virus Responsible for Hepatitis C
Jasmine Jones Community Christian School
Abstract
Hepatitis C virus (HCV) infection has reached epidemic proportions. Currently, HCV has more deaths than AID’s annually in the United States. In the United States alone, nearly four million persons are infected and without knowing. Furthermore, HCV is the leading reason for inflammation of the liver. HCV was the first virus discovered by molecular cloning. This was accomplished by cloning all the nucleic acid from the plasma of an infected chimpanzee. The test is a very simple and powerful one, because its success does not depend on knowing the identity of the genes you seek. The serum of HCV-infected animals should contain antibodies directed against a broad range of proteins, including HCV proteins encountered while combating the animal's HCV infection. Thus among the many proteins the serum can respond to in an antibody test will be some HCV proteins. The investigators can use the serum as an examination for the presence of HCV proteins in bacterial cells, which would not have any other animal proteins to confuse the meaning of a positive reaction. Robert Webster and Richard Webby worked to trace the evolution of swine flu in North America (Viruses and simple organisms).
The first was discovered in a North Carolina factory farm in 1998. Since the 1918 pandemic, an H1N1 flu virus has circulated in pig populations, becoming one of the most common causes of respiratory disease on North American pig farms. In 1998, however, a barking cough resounded throughout a North Carolina pig farm in which all the thousands of breeding sows fell ill. An aggressive H3N2 virus was discovered. Dr. Robert Webster, one of the world’s leading experts on flu virus evolution, blames the emergence of the 1998 virus on the “recently evolving intensive farming practice in the USA, of raising pigs and poultry in adjacent sheds with the same staff,” a practice he calls “unsound.” (Viruses and simple organisms). Within a year, it had spread across the United States. This rapid spreading across the country has been blamed on long-distance live animal transport (Viruses and simple organisms).
In the 1980s, more than 85 percent of all North Carolina pig farms had fewer than 100 animals. By the end of the 1990s, operations confining more than 1,000 animals controlled about 99 percent of the state’s inventory. The majority of U.S. pig farms now confine more than 5,000 animals each. A veterinary pathologist from the University of Minnesota stated: With a group of 5,000 animals, if a novel virus shows up it will have more opportunity to replicate and potentially spread than in a group of 100 pigs on a small farm (Viruses and simple organisms).
With massive concentrations of farm animals within which to mutate, these new swine flu viruses in North America seem to be on an evolutionary fast track, jumping and repeating between species at an unprecedented rate. “We used to think that the only important source of genetic change in swine influenza was in Southeast Asia,” said Christopher Olsen, a molecular virologist at the University of Wisconsin, Madison (Viruses and simple organisms). Now, “we need to look in our own backyard for where the next pandemic may appear” (Viruses and simple organisms).
Houghton and his colleagues tested each colony for its ability to cause a visible immune reaction with serum isolated from HCV infected chimpanzees in order to identify an HCV protein from among a background of thousands of bacterial proteins (Viruses and simple organisms). The serum of HCV-infected animals should contain antibodies directed against a broad range of proteins, including HCV proteins encountered while combating the animal's HCV infection. Thus among the many proteins the serum can respond to in an antibody test will be some HCV proteins. The investigators can use the serum as a probe for the presence of HCV proteins in
