Hepatitis refers to liver inflammation, often caused by a virus. The most common types of viral hepatitis are hepatitis A, B and C. These diseases differ in terms of how they are transmitted and whether they cause short- or long-term illness, or both. Many people don't experience symptoms with hepatitis A, B or C, but those who do typically develop flulike and digestive symptoms. Despite overlap in symptoms among these diseases, there are also notable differences, including how quickly symptoms typically appear, which symptoms are most common and who is most likely to develop them.
The hepatitis A virus, or HAV, spreads by ingesting food or drinks contaminated with an infected person's stool, even in microscopic amounts. Hepatitis A is a short-term, or acute, illness. Many people with HAV never experience symptoms, but the likelihood increases with age. The Centers for Disease Control and Prevention reports that about 70 percent of children younger than age 6 are asymptomatic with HAV, while most older children and adults develop symptoms. Common symptoms of viral hepatitis, including hepatitis A, include: -- Fever, fatigue and body aches. -- Poor appetite, abdominal pain, nausea and vomiting. -- Light-colored stools and dark urine. -- Yellowing of the skin or whites of the eyes, known as jaundice.
Symptoms typically develop suddenly 2 to 7 weeks after HAV exposure, and fever is particularly common with this form of viral hepatitis. Jaundice is the last symptom to develop and reflects liver cell damage with related accumulation of a yellow substance called bilirubin in the bloodstream. Seventy to 80 percent of adults with HAV develop jaundice, which usually starts about a week after other symptoms. Once jaundice appears, other symptoms lessen -- though fatigue may persist.
The hepatitis B virus, or HBV, is spread through blood, semen or other bodily fluids. Common routes of infection include unprotected sex and sharing injection drug equipment. Thirty to 50 percent of HBV-infected adults and children older than age 5 develop symptoms, CDC reports. Only 5 to 15 percent of children aged 1 to 5 develop symptoms, and HBV infection during infancy is rarely symptomatic.
Flulike symptoms and digestive upset usually appear 6 weeks to 6 months after HBV exposure and last 3 to 10 days. These symptoms are followed by jaundice, which typically lasts 1 to 3 weeks and may be accompanied by light-colored stools and liver tenderness. Although most adults and older children who develop hepatitis B clear the infection and recover completely, the infection sometimes persists long term. This is known as chronic hepatitis B, which often progresses slowly without symptoms but can cause severe liver damage over time. The likelihood of developing chronic HBV decreases with age. While more than 90 percent of unvaccinated infants exposed to HBV become chronically infected, only 6 to 10 percent of adults and children older than age 5 develop chronic infection, according to CDC.
Hepatitis C is a blood-borne virus, like HBV. Infection most often occurs from sharing injection drug equipment. It can also be transmitted from an infected mother to her child during pregnancy or delivery. Only 20 to 30 percent of people develop symptoms during the first 6 months after infection, the stage of the illness known as acute hepatitis C. In those who experience symptoms, they usually develop 1 to 3 months after exposure to the hepatitis C virus, or HCV.
Approximately 1 in 4 people with acute hepatitis C develop jaundice, and 10 to 20 percent develop digestive system symptoms such as nausea, vomiting or abdominal pain, according to the University of Washington’s Hepatitis Web Study. Symptoms generally last 2 to 12 weeks. The majority of people infected with HCV -- 75 to 85 percent, according to CDC -- develop a persistent infection, known as chronic hepatitis C. People with chronic HCV infection usually remain symptom-free for many years and only experience symptoms after serious liver damage has occurred.
Advanced age and certain preexisting medical conditions can make viral hepatitis symptoms worse. For example, while most people with HAV recover without lasting liver damage, older adults and those who already have chronic hepatitis B or C are at increased risk for rapid liver failure, a condition called fulminant hepatitis. Similarly, people with chronic hepatitis C who contract HBV are at greater risk of fulminant hepatitis.
Coinfection with HIV and HBV or HCV is relatively common. Viral hepatitis progresses faster in people with HIV, and people with coinfection experience more liver-related health problems. In addition, high alcohol consumption and other preexisting liver diseases -- such as alcoholic liver disease and fatty liver disease -- tend to worsen symptoms of acute and chronic viral hepatitis.
Medical advisor: Tina St. John, M.D.