Hepatitis, Third Edition

Lyle Horn, Alan Hecht

Description

Hepatitis means an inflammation of the liver, but it also refers to a group of viral infections that affect the liver. There are several types of viral hepatitis, but the most common are A, B, and C. Viral hepatitis is spread through contact with infected blood, bodily fluids, or feces, though it may also result from alcohol and drug use or from other diseases. Acute hepatitis refers to the initial infection and can be mild or severe; chronic hepatitis refers to a serious condition in which the infection lasts six months or longer. Currently, vaccines are available for the prevention of hepatitis A and B viruses. This third edition of Hepatitis delves into the history, causes, and current treatments for this disease, giving valuable and up-to-date information to student researchers.

Chapters include:

• Introduction to Hepatitis


• The Phases of Hepatitis


• Looking at the Liver


• Inflammation and Immune Response


• Hepatitis A


• Hepatitis B


• Hepatitis C.

Sujets

• Santé au quotidien
• Santé au quotidien
• Science
• Live act (musique)
• Fitness
• Health
• Disease
• Medicine
• Hepatitis
• Liver
• Medical

Informations

• Publié par: Infobase Publishing
• Date de parution: 01 septembre 2019
• Nombre de lectures: 0
• EAN13: 9781438194110
• Langue: English

Extrait

Hepatitis, Third Edition
Copyright © 2019 by Infobase
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage or retrieval systems, without permission in writing from the publisher. For more information, contact:
Chelsea House An imprint of Infobase 132 West 31st Street New York NY 10001
ISBN 978-1-4381-9411-0
You can find Chelsea House on the World Wide Web at http://www.infobase.com
Contents Foreword Chapters Introduction to Hepatitis The Phases of Hepatitis and Their Common Symptoms Looking at the Liver Inflammation and the Immune Response The Story of Viruses Hepatitis A Hepatitis B Hepatitis C Hepatitis D Hepatitides E and G Conclusion Support Materials Glossary Further Resources About the Authors About the Consulting Editor Index
Foreword
The outbreak of Severe Acute Respiratory Syndrome (SARS) in the early part of the 21st century highlighted the significance of infectious disease outbreaks in the world today:  from a Chinese medical doctor who had become ill while treating patients with a clinically severe pulmonary syndrome in his home province, who then traveled to Hong Kong and stayed overnight in a hotel with international guests, the coronavirus that caused SARS spread around the world. The outbreaks that resulted, mostly in highly  industrialized countries, were typical of emerging infections in today’s globalized world.  Not only are these outbreaks serious risks to human health—often causing high mortality—they also have an effect on economies.  Fortunately the SARS outbreak was fully contained within six months – with a death toll just over 800.  But the SARS outbreaks also caused a severe shock to economies in Asia where travel, trade, and tourism came to a virtual standstill. 
Following the SARS outbreaks the International Health Regulations (IHR)—international law developed in the late 1960s to attempt to stop infectious disease at international borders—were revised.  Today the IHR provide requirements for a global response should infectious diseases cross national borders, and more importantly they require all countries to develop the public health capacity to help detect and stop infectious disease outbreaks where and when they occur. 
During the time of the revision of the IHR the related concept of global health security became an important political issue worldwide.  Its importance was highlighted by the 2013—2014 Ebola outbreaks in West Africa. Like SARS, Ebola virus infection spread across national borders to neighboring countries, and to highly industrialized countries far from the African continent.
The concept of global health security for persons living in industrialized countries with equitable access to health services is clear—it is about reducing their vulnerability to infectious disease threats that spread across national borders. 
But in many ways health security is like a chameleon that changes color depending on its environment. In addition to the collective health risk caused by the international spread of Ebola virus infection, health workers in West Africa, some infected with the Ebola virus, and Ebola-infected persons from communities they served, were forced to accept that their health care was not always effective, and not always accessible—that their own, individual health security was at risk. And many persons infected with the Ebola virus in West Africa died because their weak health systems collapsed, and care was not available to them, nor was it available to children and others who had nowhere to seek care for common infections such as malaria and other highly fatal tropical diseases.
The intertwining of collective and individual health security is a concept that must remain high on the political agenda as the IHR continue to serve as a global framework for collective health security, and as the world focuses its attention on universal health coverage, the key to realizing individual health security. At the same time the impact of deadly infectious disease outbreaks, and other outbreaks such as those caused by infections resistant to antimicrobial drugs, will remain a threat to collective and individual health security. This series of Deadly Diseases and Epidemics describes the past and present, and forecasts the future. It is important reading for anyone concerned about the spread of diseases in modern society.

David L.  Heymann, M.D. Professor, Infectious Disease Epidemiology London School of Hygiene and Tropical Medicine
Chapters
Introduction to Hepatitis

Mike was a junior at a large high school and a starting forward on the soccer team. Near the end of his junior year, he met some cousins of a friend at a party. He spent a lot of time talking with them because they were really into music and had friends who were members of popular bands. As the party was winding down, they invited Mike to stay a while and do some cocaine with them. Mike declined, but they assured him that it was not dangerous if one was careful and that they had been doing it for a long time and were not addicts. They really raved about the experience. Mike was curious and so he agreed to try it. Mike, his friend, and the two cousins gathered around the kitchen table. Cocaine was poured out into four lines on the table. Each young man inhaled (snorted) his line through a special straw and passed the straw to the next person. Mike was the last to snort. Mike felt the surge his friends told him to expect, but he found it disturbing rather than pleasurable. He hated the sense of losing control of himself. He felt guilty about trying the drug and had no desire to do it again. It was just a stupid experiment that he tried in a weak moment, he reasoned. So Mike went on with his life .
Mike had a great summer. He went to soccer camp, where he learned new ball-handling techniques and defensive maneuvers. Then he went on a long camping trip in Montana, where he did a lot of hiking and fishing. When he returned home, he was eager to start his senior year and play soccer. The team workouts went well for Mike until the first week of September. He suddenly found it increasingly difficult to keep up his usual pace during scrimmages and went home after practice feeling really tired. He also began to have a hard time getting up for school in the morning and felt exhausted all day. His coach noticed the change in Mike. Mike's soccer play had become so poor that the coach didn't start him in the first game. The coach knew this tiredness was not normal for Mike, so he urged Mike to see a doctor and he called Mike's parents .
Mike's doctor talked with him for a long time to get some clues about the cause of the unusual fatigue. When a patient complains of fatigue and has no other symptoms, a diagnosis can be very difficult to make. Sixty or more medical conditions have fatigue as a major symptom. Most of these diseases could be ruled out for Mike based on his general condition and medical history. Mike's doctor knew that he had been immunized for hepatitis A and hepatitis B as a young child. So Mike was checked for some other diseases that cause serious fatigue. He was tested for Lyme disease because he had spent so much time outdoors and might have been bitten by an infected deer tick, but the test result was negative. His thyroid gland was also checked and found to be normal. Mike's muscle strength was excellent, his heart was healthy, his blood pressure was fine, he did not have diabetes or infectious mononucleosis, and he was not anemic (having low levels of iron in the blood). Fatigue is associated with all of these diseases, but none affected Mike; he just felt tired .
When his doctor asked whether he had ever used drugs, Mike was embarrassed and did not answer honestly. After all, he had only experimented with cocaine once. The doctor asked if he had had a blood transfusion or been stuck with a syringe needle within the past year. Had he been tattooed or had his ears pierced? All the answers were no. Mike thought these were weird questions, but the doctor was trying to determine whether Mike might have been exposed to viruses that are present in the blood and can infect the body only by direct entry into the blood .
Mike's doctor ordered serological tests to check for hepatitides A, B, and C. He knew Mike had been vaccinated, but sometimes the vaccinations don't work. Immunity to HAV is thought to last a lifetime, but HBV immunity can wane after 10 years or more in some people. The results showed that Mike was still immune to HAV and HBV. The EIA-2 test for anti-HCV antibodies was positive, and this finding was confirmed with an RIBA-2 test. A six-month follow-up showed that Mike was still HCV-positive. The likelihood was that he would develop chronic hepatitis C. Liver function tests were then done, and Mike's serum ALT level was high. This measurement provided an important baseline for monitoring the progress of Mike's disease.
The liver specialist to whom Mike was referred wanted to see him every six months to check on the progress of the infection. Serological tests and liver enzyme measurements were done. On Mike's first visit, the specialist also checked the virus genotype because this information can influence the treatment. Mike had HCV type 1b—common among drug abusers in the United States. Unfortunately, it is the most difficult type to treat.
Mike talked to the specialist about how he could have acquired the virus. This time, he was honest about his one-time experiment with cocaine. The doctor explained that it was possible to acquire the virus this way, although it is not a common route. Dirty needles used by intravenous drug abusers are the most common source of infection in the United States. In Mike's case, he inserted a snorting straw into his nose, where it may have either scraped the soft tissue in his nose and ca