Talking to your doctor about Childhood Vaccines
Hepatitis is the medical term for inflammation of the liver. Hepatitis may be acute (lasting only for the short term, after which a person recovers) or chronic (lasting for the long term, usually more than 6 months).
There are many causes of hepatitis, including viruses, alcoholism, and medications. Viral hepatitis is now a major cause of chronic hepatitis in North America. There are five hepatitis viruses: A, B, C, D, and E. There are also other viruses that can cause liver inflammation, like Epstein-Barr virus and cytomegalovirus, but these viruses are not called hepatitis viruses.
Hepatitis A and B (HAV and HBV) are common causes of liver inflammation in North America. Statistical data from 1999 and 2006 showed that around 600 to 900 new cases per year of HAV and HBV were being diagnosed in Canada. Since many infected people have no symptoms; however, we can assume the true rate of infection is higher than this. Many experts believe that up to one-third of the population has been infected with HAV at some point.
Among people born in North America, hepatitis A is most common in children and young adults, while hepatitis B is most common in adults between the ages of 20 and 40 years.
Hepatitis A is mainly transmitted through the fecal-oral route. That means infected people shed viruses in their feces. If they don't observe proper hygiene, the virus can end up on their hands. It's then spread by food they've handled, or sometimes by touching other people who then bite their nails, handle their food, and so on.
The virus can survive on tabletops, doorknobs, telephones, or other such places for 2 or 3 hours at room temperature. Although less common, you can also get hepatitis A from direct contact such as kissing, through sexual contact, or by sharing needles. Though many people who are infected have no symptoms, they can still pass on the disease.
People at high risk for hepatitis A include:
Hepatitis B is spread by blood and body fluids. The main routes of transmission are through sexual contact, sharing needles, tattooing and body piercing, and childbirth (when the baby is likely to pick up the virus from the mother through the birth canal). Hepatitis B has an additional complication - some infected people become lifelong carriers, whether they have symptoms or not. Many infected people are asymptomatic (without symptoms) but can pass on the virus.
People at high risk for hepatitis B include:
Hepatitis A has an incubation period (the time between infection and first symptoms) of 2 to 6 weeks. Hepatitis B only shows itself after 2 to 6 months.
Flu-like warning symptoms (called a prodrome) often appear about 3 to 10 days before liver symptoms arrive. Symptoms include low-grade fever, muscle aches, loss of appetite, nausea, vomiting, and fatigue. Smokers may find they suddenly dislike smoking. In hepatitis B, these symptoms may be accompanied by joint pains and skin eruptions resembling urticaria (hives).
After this, the urine may darken and jaundice may appear. In jaundice, the skin and the whites of the eyes take on a yellow tint. The inflamed liver is not able to perform its usual metabolic functions so that a substance called bilirubin (a byproduct from old red blood cells that also causes bile to be yellow) builds up in the body. Bile is a fluid secreted by the liver that contains cholesterol, bile salts, and waste products such as bilirubin.
Usually, you start to feel better when the jaundice arrives, even though you continue to look worse. The jaundice only lasts for about one week in hepatitis A infection. After that you start to recover and will generally feel and look yourself again within a month. Rarely, hepatitis A may come back briefly a month later, but won't last long. After recovering from hepatitis A, you're immune for life.
With hepatitis B, the jaundice lasts for about two weeks. However, the hepatitis B infection doesn't always get cleared out of the system. If this happens, you will probably not have any symptoms, but you'll be a lifelong "carrier" and must take special precautions such as warning sexual partners. You may also suffer from chronic liver inflammation (chronic viral hepatitis) for the rest of your life.
Chronic hepatitis B is most likely to occur in infants (around a 90% chance if infected in the first year of life) and least likely in adults (5% chance overall). It can lead to cirrhosis (scarring) of the liver. It also increases the risk of developing liver cancer.