What is viral hepatitis?
There are five viral hepatitis diseases (A, B, C, D and E), each caused by a different virus. All five can lead to acute hepatitis, although B, C, and D can cause chronic hepatitis.
Antibody blood tests detect infection by any of the hepatitis viruses, but protective vaccination is available (and recommended) only for hepatitis A and B viruses.
Symptoms of viral hepatitis
Symptoms of hepatitis can include:
- abdominal pain
- joint pain
Diagnosing viral hepatitis
Diagnosis procedures for viral hepatitis may include:
- a physical examination
- blood tests
- imaging studies (CT scan)
- liver biopsy
- Hepatitis A virus (HAV)
One third of reported U.S. cases of hepatitis are infectious hepatitis, caused by hepatitis virus A (HAV). This infection is spread by direct contact with infected feces or indirectly through infected fecal contamination of food or water. Rigorous personal hygiene is essential in limiting thespread of HAV, although only the elderly and those suffering from HIV/AIDS are usually at risk of dying.
HAV vaccination is recommended for: (i) travellers; (ii) those at high risk of HAV infection; and, (iii) those with liver disease.
Hepatitis B virus (HBV)
Hepatitis B virus (HBV) infection is reported in 300,000 Americans yearly, 10% of whom develop chronic liver disease and an increased risk of liver cancer. HBV is spread by exposure to infected body fluids (urine, semen, blood clotting products) by nursing mothers and via unprotected sex.
There is no cure for HBV, although interferon alpha is effective in up to 50% of patients with chronic hepatitis B.
Hepatitis C virus (HCV)
Approximately 200,000 new U.S. cases of hepatitis C are reported annually, mostly among African-American and Hispanic males. This disease, which chronically affects close to three million Americans, is primarily spread by contaminated blood or needles, but unprotected sex and mother-to-child transmission may also occur.
As with HBV, there is no cure for HCV, although about 50% of acute cases recover spontaneously. Interferon alpha is also effective in reducing severity of HCV disease.
Hepatitis D (HDV) virus
Hepatitis D virus (HDV) can be found in the setting of acute HBV infection, in which case the co-infection goes into remission, or else in the setting of chronic HBV, when persistent HDV infection develops, eventually leading to chronic liver disease. HDV is spread by contaminated blood and needles, and by unprotected sex.
Hepatitis E (HEV) virus
Finally, hepatitis E virus (HEV), a common third-world disease —transmission has not been documented in the U.S.— causes acute hepatitis which usually resolves itself. With no prevention or cure available, travellers are recommended to observe very strict hygiene practices.
Treating viral hepatitis
Depending on the type of viral hepatitis, medications may include:
- protease inhibitor