Hepatitis is a disease that causes inflammation of the liver. Hepatitis is mainly caused by viral infections, but alcohol abuse can also lead to the disease. The five hepatitis viruses include A, B, C, D, or E. Viruses that cause diseases such as herpes, mononucleosis and cytomegalovirus infections can also cause the liver to inflame. Hepatitis cases are classified as acute (short-term) or chronic (long-term). Hepatitis is classed as chronic when the disease affects the patient for at least six months.
Acute hepatitis is the rapid, sharp, painful onset of the disease. Acute symptoms are more painful for patients, but they last for only three or four weeks. Depending on the patient's immune system, acute symptoms range from mild to severe liver failure. Some types of hepatitis viruses are more likely to create acute symptoms such as B and E, while types A and C normally induce mild symptoms.
Chronic hepatitis is less common and symptoms are less severe. Chronic hepatitis remains in the patient's system for months or even years. Its symptoms are usually mild, but continual infection and destruction of the tissue causes liver damage leading to cirrhosis. Cirrhosis is caused by scarring of the liver, and it can lead to failure or liver cancer.
Acute and chronic hepatitis are caused by different types. They are also transmitted differently. For instance, hepatitis A is an acute infection and is transmitted through fecal-oral routes from food contamination. Hepatitis C and B are from blood transmission and main forms that cause chronic symptoms. Drugs are also causes for chronic hepatitis such as alcohol or medicine. Overuse of medications such as isoniazid (a tuberculosis treatment) and acetaminophen (Tylenol) can lead to chronic hepatitis.
Symptoms of each type of hepatitis infection are mainly distinguishable by their severity. Chronic hepatitis symptoms are not normally detected until cirrhosis occurs. Chronic symptoms are mild, creating feelings of malaise and fatigue. Rapid, acute symptoms include severe nausea, vomiting and pain in the abdomen. For both hepatitis types, jaundice from liver failure is common.
Vaccinations for hepatitis A, B and E are available. Vaccination for type B is recommended for everyone, A is normally given to people exposed to the disease, and E is common in endemic areas. There are no vaccinations for types C and D. Hepatitis D occurs in patients who are infected with B, so vaccination against B greatly lowers the risk for D. Hepatitis C is a growing disease in intravenous drug users, so the use of clean needles lowers the risk.