Acute viral hepatitis refers to inflammation of the liver caused by infection with one of several hepatitis viruses, including hepatitis A, hepatitis B, hepatitis C, hepatitis D, and hepatitis E. These viruses primarily target the liver, leading to a range of symptoms and potential complications. Here’s an overview of acute viral hepatitis:
- Hepatitis A: Hepatitis A virus (HAV) is typically transmitted through the fecal-oral route, often via contaminated food or water. Symptoms of acute hepatitis A infection may include fatigue, nausea, vomiting, abdominal pain, fever, jaundice (yellowing of the skin and eyes), and dark urine. Hepatitis A infection is usually self-limiting, and most people recover without complications. Hepatitis A vaccination is available and recommended for prevention.
- Hepatitis B: Hepatitis B virus (HBV) is transmitted through exposure to infected blood or body fluids, including sexual contact, sharing of needles, or from mother to baby during childbirth. Acute hepatitis B infection can cause similar symptoms to hepatitis A but may lead to chronic infection in some cases. Chronic hepatitis B infection can increase the risk of liver cirrhosis, liver failure, and hepatocellular carcinoma (liver cancer). Hepatitis B vaccination is available and recommended for prevention.
- Hepatitis C: Hepatitis C virus (HCV) is primarily transmitted through exposure to infected blood, such as through sharing of needles or syringes among injection drug users or through contaminated medical equipment. Acute hepatitis C infection may be asymptomatic or cause mild symptoms similar to other types of viral hepatitis. Most cases of acute hepatitis C progress to chronic infection, which can lead to liver cirrhosis and liver cancer. There is no vaccine for hepatitis C.
- Hepatitis D: Hepatitis D virus (HDV) is a defective virus that requires HBV for its replication. Hepatitis D infection occurs only in individuals who are already infected with HBV. Acute hepatitis D infection can cause more severe liver disease compared to hepatitis B alone, and it may increase the risk of fulminant hepatitis. Hepatitis B vaccination also provides protection against hepatitis D.
- Hepatitis E: Hepatitis E virus (HEV) is transmitted primarily through ingestion of contaminated water or food, particularly in developing countries with poor sanitation. Acute hepatitis E infection is usually self-limiting, but it can be more severe in pregnant women, leading to fulminant hepatitis and high mortality rates. There is no vaccine widely available for hepatitis E.
Acute viral hepatitis is diagnosed based on clinical symptoms, laboratory tests detecting viral antigens or antibodies, and liver function tests showing elevated levels of liver enzymes. Treatment for acute viral hepatitis is primarily supportive and focused on relieving symptoms, preventing complications, and promoting liver recovery. In some cases, antiviral medications may be prescribed for certain types of acute hepatitis, such as hepatitis B or C. Prevention strategies include vaccination for hepatitis A and B, practicing good hygiene, avoiding high-risk behaviors, and ensuring safe blood transfusions and medical procedures. Early diagnosis and management are essential for preventing complications and improving outcomes in individuals with acute viral hepatitis.