According to the World Health Organization (WHO), hepatitis is an inflammation of the liver. This condition may resolve without treatment in some cases, but in others, it can progress to liver fibrosis (scarring), cirrhosis (permanent liver damage), or even liver cancer. The most common cause of hepatitis is viral infection. However, it can also result from exposure to toxic substances (like alcohol and certain medications), other infections, or autoimmune diseases, where the body mistakenly attacks its own liver cells.
Types of Hepatitis
There are five primary types of hepatitis viruses: A, B, C, D, and E. These types are significant due to their impact on global health, causing widespread illness, deaths, and the risk of transmission.
Hepatitis B and C are especially concerning, as they can lead to long-term (chronic) infections in hundreds of millions of people worldwide and are major causes of cirrhosis and liver cancer.
- Hepatitis A and E are usually transmitted through ingestion of contaminated food or water.
- Hepatitis B, C, and D are transmitted through contact with infected body fluids. This includes exposure to contaminated blood, unsterile medical equipment, or sexual contact. Hepatitis B can also be passed from an infected mother to her child during childbirth, or through close contact within households or between sexual partners.
Symptoms of Hepatitis
Acute hepatitis (short-term and potentially severe) may not cause noticeable symptoms in some individuals. When symptoms do appear, they may include:
- Jaundice (yellowing of the skin and eyes)
- Dark-colored urine
- Extreme tiredness
- Nausea and vomiting
- Abdominal pain
Overview of Hepatitis Viruses
- Hepatitis A (HAV):
- Spread via contaminated food and water
- Usually causes mild illness, but can occasionally be severe
- Preventable with a safe and effective vaccine
- Hepatitis B (HBV):
- Spread through infected blood, semen, and other bodily fluids
- Can be transmitted from mother to child, through blood transfusions, or via contaminated needles
- Healthcare workers face risk from accidental needlestick injuries
- Preventable with a reliable and effective vaccine
- Hepatitis C (HCV):
- Mainly spread through contact with infected blood
- Common routes include shared needles and unsafe blood transfusions; rarely through sexual contact
- No vaccine is currently available
- Hepatitis D (HDV):
- Only occurs in individuals already infected with hepatitis B
- Co-infection with HBV worsens the severity of the disease
- The hepatitis B vaccine also provides protection against hepatitis D
- Hepatitis E (HEV):
- Transmitted through contaminated food and water
- Can cause significant illness, including in developed countries
- A vaccine exists but is not widely accessible
