Hepatitis is a potentially fatal disease that affects 1 in 12 people worldwide, often without obvious symptoms.  As one million people die each year from chronic hepatitis infection, viral hepatitis is among the top 10 infectious disease killers, according to the CDC.    

The World Hepatitis Alliance and the World Health Organization (WHO) recognize July 28, 2012 as World Hepatitis Day in honor of Dr. Baruch Blumberg who won the 1976 Nobel Prize in Medicine for his discovery of the hepatitis B virus.  Launched in 2008, World Hepatitis Day focuses on raising awareness of the different types of hepatitis, including their cause, treatment and prevention.

What is hepatitis?

Caused by a viral infection, hepatitis is an inflammation of the liver.  Scientists have identified five unique hepatitis viruses which are referred to by type - A, B, C, D, and E - each causing serious liver disease.  According to the World Health Organization, hepatitis types B and C “lead to chronic disease in hundreds of millions of people [and] are the most common cause of liver cirrhosis and cancer.” 

People experiencing an acute hepatitis infection may have limited or no symptoms.  Or, they may have symptoms such as jaundice (yellowing of the skin and eyes), dark urine, extreme fatigue, fever, loss of appetite, nausea, vomiting and abdominal pain.

Hepatitis A and E:

The hepatitis A virus is primarily contracted by eating food or drinking water which is contaminated with the feces of an infected person.  It is a common food-born infection associated with inadequate sanitation, poor hygiene, and lack of safe water.  An estimated 1.4 million cases of hepatitis A occur each year worldwide.  The typical incubation period following exposure to the hepatitis A virus is 14-28 days.  While hepatitis A does not cause chronic liver disease and is rarely fatal, it may take weeks or months for persons to recover enough from the illness to return to normal daily activities.   

The hepatitis E virus is also spread through contaminated water.  Every year, 20 million cases of hepatitis E infection occur worldwide with 70,000 related deaths.  The incubation period for the virus ranges from 3 to 8 weeks and an infection typically resolves within 4 to 6 weeks.  Children who become infected are mostly asymptomatic or have very mild symptoms, but without jaundice.  Symptomatic infections are most common in young adults aged 15 to 40 years.  Very rarely, hepatitis E can cause acute liver failure and death.  Cases of chronic hepatitis E infection or reactivated infection have been reported in persons who are immunosuppressed.

Hepatitis B and D:

The hepatitis B virus is transmitted through contact with infected blood, blood products, or body fluids.  Hepatitis B is the most serious type of viral hepatitis infection.  It can cause chronic liver disease which increases the risk of death from cirrhosis of the liver and liver cancer.  The hepatitis B virus can survive outside the body for over a week and is 50 to 100 times more infectious than HIV.  The average incubation period is 90 days but can vary from 30 to 180 days.