Hepatitis: causes, types, symptoms, diagnosis, treatment and prevention

Major causes and types

The most commonly referenced forms are viral hepatitis: Hepatitis A, Hepatitis B and Hepatitis C. Viral agents are the leading infectious causes; examples include a variety of viruses that selectively infect hepatocytes. Other infectious organisms—bacteria, fungi or parasites—can also inflame the liver. Classic bacterial infections that may involve the liver include agents associated with tuberculosis or syphilis, while parasitic diseases such as malaria may cause liver involvement in some cases.

Non-infectious causes

Not all hepatitis is infectious. Long-term heavy alcohol use is a major noninfectious cause and can produce alcoholic hepatitis; sustained high intake—such as consuming more than three alcoholic drinks per day—raises risk of alcohol-related liver injury. Various drugs and environmental chemicals can be hepatotoxic; a prominent example is paracetamol (acetaminophen), where overdose is a leading cause of acute liver failure and must be treated urgently (see overdose management).

Symptoms and clinical course

Symptoms range from none or mild fatigue to jaundice (yellowing of skin and eyes), abdominal pain, dark urine and pale stools. Blood tests often show raised liver enzymes. Some forms are self-limited, while others become chronic and progress to scarring (cirrhosis), liver failure or liver cancer over years. The pattern of progression depends on the cause—for example, Hepatitis A usually causes acute illness without chronic infection, whereas Hepatitis B and C can persist and lead to long-term liver damage.

Diagnosis, treatment and prevention

Diagnosis combines clinical assessment with blood tests (serology and molecular assays), imaging and sometimes biopsy. Treatment varies: supportive care for many acute cases, specific antiviral medications for chronic viral hepatitis, and avoidance of hepatotoxins for drug- or alcohol-related disease. Vaccination prevents Hepatitis A and B, routine screening of blood products and safe-injection practices reduce transmission, and targeted public-health measures reduce population risk.

Key distinctions and public-health importance

• Hepatitis A: usually fecal–oral transmission, acute illness, vaccine-preventable (A).
• Hepatitis B: blood and bodily-fluid transmission, can be acute or chronic, vaccine-preventable (B).
• Hepatitis C: blood-borne, frequently becomes chronic but curable with direct-acting antivirals (C).

Prevention checklist

• Vaccination where available (A and B), safe-sex practices and screened blood supplies.
• Avoid sharing needles and ensure sterile procedures in healthcare and tattooing settings.
• Limit alcohol intake and use medications carefully; follow dosing directions for paracetamol and seek help in suspected overdose.
• Maintain food and water hygiene to reduce fecal–oral transmission of some types.

For further reading on liver anatomy and function, consult resources about the liver and inflammation (inflammation), or authoritative guidance on alcohol harms (alcohol) and safe medication use (drugs). Additional specialized topics include infections like tuberculosis, syphilis and parasitic illnesses such as malaria, which may involve the liver in some clinical contexts.