Introduction:
Hepatitis A virus (formerly known as Enterovirus 72) has a long history and it still has a big impact on human populations in the modern world. From time of the ancient Greek doctor Hippocrates, Hepatitis A virus (HAV) was noted for causing jaundice. By the 8th century, it was realized that icteric disease was caused by an infectious agent. Later in the history, in 1885, it was discovered by scientists that hepatitis could be spread through blood transfusions. Now, it is well- known that the virus is mainly transmitted via fecal-oral route which results from contamination of food and water by fecal matter and direct contact with infected individuals. Initially another icteric agent, Hepatitis B virus, was isolated in 1973 by Robert H. Purcell. This is followed by isolation of HAV from marmoset liver explant cultures in 1979(5). Understanding of HAV had started after WWII because of its massive impact on the soldiers and civilians under the contamination favored conditions of war. HAV was first visualized under electron microscope at the National Institutes of Health in the feces of volunteers who have had HAV infection (1, 2).
Hepatitis A virus causes acute viral hepatitis which is one of the most common infectious diseases that is resulted from inflammation of liver. HAV is not the only infectious agent that causes acute viral hepatitis. Several different viruses, named hepatitis A, B, C, D and E cause inflammation of liver. Different hepatitis viruses belong to different virus families. HAV is a small, 27 nm cubically symmetrical single stranded RNA virus with positive (+) strand polarity and is classified as a member of picorna virus family. It has also been classified as the main virus of hepatovirus genus...
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... hygiene may be more common. In the general population, seroprevalence rate of anti-HAV antibodies varies from 15% to 100% in different countries of the world. In developing countries, most infections occur by 5 years of age and seroprevalence rates can become as high as 100%(7). North Europe has the lowest seroprevalence rate in the world. Decreased seroprevalence is problematic as it is indicating that most of the individuals in the defined population are susceptible to HAV infection which can result in outbreak of an epidemic. In 1988, an epidemic occurred due to ingestion of inadequately cooked bivalve mollusks from sewage polluted water in Shanghai and resulted in infection of approximately 300,000 people(1). In regions where majority of individuals are susceptible to HAV infection, routine vaccination is suggested for prevention of HAV epidemic outbreaks(7).
Hepatitis A is a usually short acting virus that occurs in humans and monkeys. It is caused by the Hepatovirus and the species is Hepatitis A Virus. There are two major ways in which Hepatitis A can be transmitted. One way is from person to person. This transmission occurs when the fecal matter of an infected person gets ingested by another person. Other ways Hepatitis A can be transmitted from person to person are through direct contact with an infected person, such as sexual contact, and sharing of needles for intravenous drug use. Hepatitis A can also be transmitted through coming in contact with contaminated food or water. Also foods that are uncooked or undercooked and have been contaminated with Hepatitis A can transmit the virus. (Bennett,
Hepatitis B virus infection is caused by a DNA virus belonging to the hepadnaviridae family of viruses. Approximately 2.2 million people in the United States of America are infected with Hepatitis B virus. Many of these patients, though they appear healthy, continue to spread the virus to others. Hepatitis B virus infection can be transmitted in the following ways: contact with contaminated blood (shared needles), sexual contact, and from mother to child. Unlike Hepatitis A, Hepatitis B is not spread through food, water, or causal contact. 95% of adults who get Hepatitis B can clear the virus through their system. However the remainder of the adults go on to develop chronic hepatitis B infection. This can
The purpose of epidemiology is to better understand the burden and causes of health issues in humans. This helps decrease the risk of disease and improve health. Infectious diseases are caused by micro-organisms, transmitted to humans by humans, animals, or environment. Infectious disease usually follow a recognizable pattern. In this paper Hepatitis B also known as serum hepatitis will be discussed. Hepatitis B is a viral infection that can cause acute or chronic disease. Hepatitis B is a communicable disease. This paper will describe Hepatitis B, the demographic of interest, the determinants of health, the epidemiologic triangle, environmental factors, the role of community health nurse, and a national agency that addresses Hepatitis B.
Hepatitis B Virus (HBV) is a virus that attacks the liver. The virus is transmitted through blood and bodily fluids. This can occur through direct blood-to-blood contact, unprotected sex, use of contaminated needles, and from an effected mother to her newborn during the delivery process. The majority of people do not have noticeable symptoms when they are first infected with the HBV. People who do not know they are infected with the HBV, their body can respond in different ways. I learned that some of the common symptoms of Hepatitis B infection include fever, fatigue, muscle or joint pain, loss of appetite, mild nausea, vomiting, and dark-colored urine. Some of the serious symptoms that require immediate medical attention and maybe even hospitalization are: severe nausea and vomiting, yellow eyes and skin (jaundice), bloated or swollen stomach.
Hepatitis B virus (HBV) is a severe and common virus that has infected ‘more than two billion people alive today at some point in their life.’1 It is a hepadanavirus that interferes with the liver functions as it replicates in the hepatocytes (liver cells) and induces a immune response that is responsible for the inflammation of liver.2 Viruses are not motile, which means that HBV is also sessile and does not form spores. The spherical virion, is called a Dane Particle3 that is 42nm in diameter binds to the surface of hepatocyte.1 The virion itself contains an inner protein core, 27nm thick filled with circular partially double stranded DNA, DNA polymerase and reverse transcriptase.1 It is an enveloped virus, so it also holds an outer lipoprotein envelope4 that is 7nm thick and is comprised of many embedded surface proteins such as surface antigen for viral binding and entry.1 HBV has an average incubation period of three months, which means that it does not start showing symptoms for the first three months that the person is infected and that person can unknowingly infect others.2 ...
HAV is known to be an infectious disease that usually occurs in children and young adults .The disease is usually transmitted from person to person through contaminated food, liquids or oral fecal route. An example would be when someone is carrying the virus and doesn’t wash their hands after using the restroom and then puts food in their mouth. HAV is most common in developing countries because of the living conditions and inadequate water, poor sewage facilities and sanitary conditions. The highest HAV levels in the world are from India,” Earlier reports suggest that India is hyperendemic for HAV infection2,4-6 with very high infection rates,” (Sowmyanarayanan). Most HAV are without severe complications, “Virus HAV infection rarely causes fulminant hepatic failure in people…,” (Vento,p.1) . The symptoms for HAV are high fever, nausea, vomiting and jaundice...
Hepatitis B is a DNA viral infection that causes damage and inflammation to the liver. It was first discovered in 1965 by Dr. Baruch Blumberg. The HBV virus is very contagious and is even thought to be the most serious form of viral hepatitis and the most common viral infection on Earth. “HBV is 100 times more infectious than HIV.” (Green, 2002, pg. 7) The virus can survive for about one week outside the body on a dry surface. According to Green (2002, pg. 7), “One in twenty Americans has been infected with the virus at some point in their lives.” Between the ages of 15-39 is when 75% of new HBV infections occur, according to Green (2002, pg.8).
Acute HBV infection is the most common type of infection in low endemic countries. The incubation period, from transmission to clearness, ranges from 40-180 days. The infection is either symptomatic or asymptomatic/ fulminant hepatitis. Children under the age of 5 years rarely experience symptomatic infection (10%), where’s about 30-40% infected adults and children above age 5 experience a symptomatic infection with yellowing of skin and teeth, vomiting, fatigue, laxity and abdominal pain [1].
“Hepatitis is an inflammation of the liver.”("What Is Hepatitis?") There are three main types of hepatitis. These include hepatitis A, B, and C. These three types of hepatitis cause the most concern to medical staff due to their ability to spread and cause outbreaks. “Hepatitis A is a contagious liver disease that results from infection with the Hepatitis A virus.” (Centers for Disease Control and Prevention) It can range from acute to chronic. An individual can become infected with hepatitis A if they eat or drink food or water that has been contaminated with the virus. Some common “sources of vitamin A include shellfish, fruits, vegetables, ice and water”. (U.S. National Library of Medicine. “Hepatitis A.”) Hepatitis B is a serious, endemic, worldwide disease that can occur at any age. (Wilkins 45) The hepatitis B virus causes hepatitis B infection. Hepatitis B is transmitted though contact with the blood or bodily fluids of an infected person. (U.S. National Library of Medicine. “Hepatitis B.”) Hepatitis C...
Hepatitis C is a disease that is caused by the hepatitis C virus. This virus is a single stranded, enveloped, positive sense RNA virus.2
Hepatitis A is a virus or an infection that causes liver disease and inflammation of the liver. According to Centers for Disease and Prevention, hepatitis A is a self- limited disease that does not cause a chronic infection and it is rarely fatal. The virus is an infectious disease of the liver which cannot be transmitted by sneezing and coughing. It is usually transmitted from person to person through the feces or the mouth, from consuming contaminated food or water. Many people do not experience any symptoms of hepatitis A, but if someone was to get it, then the symptoms could last from 2 weeks to 6 weeks. The blood is tested to determine how the liver is functioning. The blood is usually taken from the vein in the arm and
Hepatitis A is an acute infection of the liver that travels through your bloodstream and gastrointestinal tract (2). It is transmitted person to person through fecal contamination. Ingesting contaminated food and water is the main source, this usually occurs when an infected food handler prepares food without appropriate hand hygiene (3). Outbreaks are fairly common in institutions, prisons and military forces. An early infection of Hepatitis A can mimic the flu with symptoms such as being febrile, lethargy, nausea, anorexia, abdominal discomfort and eventually causing severe jaundice (1). This virus can progress and cause liver failure and even death if not treated promptly (3).
There is a disease spreading out in the world called Hepatitis C. It affects the liver and may cause the liver to fail. This disease is caused by a virus called Hepatitis C virus which is also known as HCV. About 32,000 people are affected with this disease per year only in the United States area. Some It’s a disease with many symptoms and many causes. of these symptoms are easy bruising, upset stomach and fever. These are just some of the many symptoms that come from the virus. Hepatitis Cs nature of the causative agent is determined by many things. The biological data of this disease is filled so much information. It is estimated that over 180 million people have gotten Hepatitis C and it is growing.
Hepatitis B, an infectious disease caused by the Hepatitis B virus (HBV, a DNA virus), was formerly called serum hepatitis, inoculation hepatitis and post-transfusion hepatitis. Infection with HBV may result in acute, fulminant or chronic hepatitis, sometimes even resulting in a chronic asymptomatic carrier state, apart from hepatocellular carcinoma and liver cirrhosis (Davis 179). The disease is transmitted when an individual comes in contact with infected blood or objects. It may also be transferred from an infected mother to her infant either during or after birth (Zuckerman et al. 211). Transmission may also occur by accidental inoculation from infected needles and hospital equipment, intravenous drug abuse, body piercing, tattooing, and mouth-mouth kissing (Zuckerman et al. 210). The risk of Hepatitis B is particularly high in individuals with multiple sex partners, and in homosexuals. The HBV virus occurs in morphologically different forms in the serum of infected individuals. HBV infection has an incubation period of about 75 days. Systemic symptoms of the disease include fatigue, fever, dyspepsia, arthralgia, malaise, and rash, while local symptoms include hepatomegaly, jaundice, dark urine, and pale stools (Davis 179; Zuckerman et al. 210).
Hepatitis B was the first of the hepatitis viruses to be discovered. There are seven genotypes for hepatitis B (Zein & Edwards, 2009). There are two forms of the disease, acute and chronic. Acute hepatitis B is a form which lasts less than six months, whereas chronic hepatitis B lasts from six months on. Symptoms of acute hepatitis B include: fever, abdominal upset, nausea, decreased appetite, vomiting, and changes in the way things taste or smell (Zein & Edwards, 2009). Some individuals infected with acute hepatitis B display symptoms, while others show no symptoms. Acute hepatitis B often goes undetected as a result.