Disease
Hepatitis C
Author
Rosemary Bewley, Biol 230, Spring 2009
Causative Agents
Hepatitis C (def) is caused by the Hepatitis C Virus (HCV), which is spherical and belongs to the virus family known as Flaviviridae. HCV is an enveloped virus containing a single-stranded RNA genome. The Hepatitis C virus is about 50 nm (def) in size
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Epidemiology
More than 4 million individuals are infected with HCV in the United States alone. Worldwide the number of individuals infected is about 42 times the number of Americans infected, a whopping 170 million. Close to 30,000 are infected with HCV in the US every year. The common age of an individual infected with HCV is between the ages 30 and 49. This disease is responsible for the spending of about $600 million a year on healthcare services in the US. This virus is also more prevalent in minority groups. In the United States alone, HCV is responsible for about 10,000 -15,000 deaths per year and the number reason why people need liver transplants. The death toll is expected to increase because of the vast number of individuals with chronic (def) HCV. About 60% of new HCV infections are widely seen among drug users who inject drugs through needles. HCV is most seen in Egypt because of prevalence of a treatment called parenteral antischistosomal therapy (def), Asia, and Africa. Individuals who are HIV positive (def) have a higher chance of also contracting this disease because of lowered immune system defenses, and the way the infection was obtained, for example through use of needles. Chimpanzees can also be affected by this virus.
Transmission
Hepatitis C can be transmitted from person to person in a variety of ways, which include use or contact with drug needles that are contaminated with HCV positive blood. Another way of drug transmission is inserting a device that is contaminated with HCV positive blood and mucus into the nose. Organ transplants and blood transfusions that are contaminated with Hepatitis C are other possible ways this virus can be transmitted. Another way this disease is acquired is through contact with unsterile medical tools used in a hospital, doctor’s office, or dentist office. An individual’s job could force them to be exposed to this virus, for example a paramedic attending to an injured individual. Things people participate in for personal activity or hobbies could expose them the hepatitis C. Examples include a football player being cut on the field, or contact with unsterile needles used in tattoo parlors for body art and body piercing. Sharing a razor or toothbrush with an infected individual could also cause the introduction of this disease into a healthy, uninfected individual because of the presence of blood on these personal hygienic items. Although HCV is not frequently thought of as a sexually transmitted disease, it can be transmitted to an individual’s sexual partner. Sexual transmission is rare yet possible. Since this virus can be transmitted sexually there is also a possibility of a mother transmitting the virus to her child during childbirth. This way of transmission is rare occurs in less than 8 out of every 100 births when the mother is HCV positive.
Signs and Symptoms
During the acute (def) phase of Hepatitis C infection more than half of those infected have no symptoms. Those who do show symptoms will tend to have itching, a decrease in appetite, symptoms seeming to resemble the flu, jaundice (def), and abdominal pain. As the infection progresses, the individual will enter the chronic (def) stage. This stage can still produce unnoticed symptoms in those infected, but damage still occurs. Symptoms that are seen during this phase include those present during the early acute (def) stage along with joint pain, depression, nausea, and trouble sleeping. Cirrhosis (def) may also develop in more than half of those infected by HCV. HCV can also lead to other conditions throughout the body such as diabetes mellitus (def), glomeruolonephritis (def), and prophyria cutanea tarda (def).
Prevention and Treatment
Prevention is the most important aspect of any disease. If an individual can prevent himself or herself from contacting a disease treatment is not necessary. Prevention of the transmission of this disease includes avoiding sharing any drug use tool that many come in contact with an individual’s blood or mucus such as needles, straws, or any other device that many be rolled and used for snorting a drug. Be aware of the cleanliness of the tattoo and piercing devices used; ensure a clean sterile needle is used every time. Protect yourself from contact with needles. Do not share personal items that could come into contact with blood, such as razors. To prevent sexual transmission use a condom properly with sexual encounter. Currently prevention vaccines do not exist.
Treatment of the disease includes the use of an antiviral (def) drug known as riboflavin. This antiviral is effective because it, like most antiviral drugs inhibits normal DNA (def) synthesis, which only takes place when inside a host cell. This drug will “look similar” to a normal nucleoside. This in turn “tricks” the virus into thinking it is usable for DNA synthesis and it is placed into the DNA strand, hence blocking normal DNA synthesis. Along with the antiviral, therapy, similar to chemotherapy is also available called pegylated interferon alpha (def). This therapy is administered for about a year up to two. Individuals who are HCV positive should receive the vaccine for types A and B so the liver is not damaged further. There are also experimental therapies and drugs that are currently being developed and tested. An example of one of these new drugs is viramidine. This antiviral is based off of riboflavin but is less intense and does less damage to the body.
Bibliography
"Hepatitis C." Centers for Disease Contol and Prevention. 26 Mar. 2009. Department of Health and Human Services. 10 Apr. 2009. http://www.cdc.gov/hepatitis/HepatitisC.htm
"Hepatitis C." Wikipedia. Wikimedia Foundation Inc. 10 Apr. 2009. http://en.wikipedia.org/wiki/Hepatitis_c
Kaiser, Dr. Gary. "Mircobiology 230 Lecture Guide." Mircobiology 230 Lecture Guide. 12 July 2006. CCBC. 19 Apr. 2009. http://student.ccbcmd.edu/courses/bio141/lecguide/index.html
Mukherjee MB,BCh, MPH, FRCPC, Sandeep. "Hepatitis C." EMedicne. 30 June 2008. Medscape. 13 Apr. 2009. http://emedicine.medscape.com/article/177792-overview
Schistosoma." The Free Dictonary. 2009. Farlex. 19 Apr. 2009. http://medical-dictionary.thefreedictionary.com/Schistosoma