5.3.4 Hepatitis
Hepatitis is an inflammatory condition of the liver.The usual causes include exposure to toxic substances，especially alcohol；obstructions in the bile ducts；metabolic diseases；autoimmune diseases；and bacterial or viral infections.A growing public health concern is the increasing incidence of viral hepatitis.Even though its mortality rate is low，the disease is easily transmitted and can cause significant morbidity and prolonged loss of time from school or employment.
Although forms of hepatitis range from hepatitis A through hepatitis E，the three most common forms are：hepatitis A，also called infectious hepatitis；hepatitis B，also called serum hepatitis；and hepatitis C.The most common causes of hepatitis A are ingestion of contaminated food，water，or milk.Hepatitis B and hepatitis C are usually transmitted by routes other than the mouth，such as from blood transfusions and sexual contact.Because of patient exposure，health-care personnel are at increased risk for contracting hepatitis B，but a vaccine that provides immunity to hepatitis B is available.There is no vaccine available for hepatitis C.Patients with hepatitis C may remain asymptomatic for years or the disease may produce only mild flulike symptoms.Treatment for hepatitis includes antiviral drugs；however，there is no cure.As the disease progresses，scarring of the liver（liver cirrhosis）（Fig.5-3）becomes so serious that liver transplantation is the only recourse.
Fig.5-3 Liver Cirrhosis
One of the major symptoms of many liver disorders，including hepatitis and cirrhosis，is a yellowing of the skin，mucous membranes，and sclerae of the eyes（jaundice，icterus）.This occurs because the liver is no longer able to remove bilirubin，a yellow compound formed when erythrocytes are destroyed.Jaundice may also result when the bile duct is blocked，causing bile to enter the bloodstream.
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Task 6 Select the best answer according to the text.
1.One of the common causes of________is the intake of contaminated food，water，or milk.
A.hepatitis A
B.hepatitis B
C.hepatitis C
D.hepatitis D
2.Which of the following statements is true about viral hepatitis？
A.It has the highest death rate.
B.It has a low incidence rate.
C.It has little impact on people’s life.(https://www.daowen.com)
D.It is a contagious disease.
3.One is most likely to get hepatitis B from all of the followings except________.
A.long-time exposure to patients with hepatitis B
B.blood transfusion
C.handshaking with patients who are infected
D.sexual intercourse
4.Which of the following statements about hepatitis C is false？
A.Currently，vaccine for hepatitis C is unavailable.
B.Patients may not be aware of any symptom for years.
C.It may develop only mild flulike symptoms.
D.It can be cured with antiviral drugs.
5.________is one of the major symptoms for many liver disorders，including hepatitis and cirrhosis.
A.Fever
B.Jaundice
C.Weight gain
D.Flulike symptom