Previously known as infectious hepatitis, Hepatitis A is one of five known viruses that cause inflammation of the liver (the others are B, C, D and E). The Centers for Disease Control and Prevention estimate that each year, more than 90,000 children and adults are infected with this virus, making it the sixth most commonly reported infectious disease in the United States. Over the past several decades, areas in the Western U.S. have had substantially higher rates of hepatitis A disease than the rest of the country, but all states are affected. Worldwide it is estimated that 10 million people acquire the hepatitis A virus every year. If you or someone you know has recently been diagnosed with Hepatitis A, this information may be of benefit to you.
Your Liver Lets You Live
First a few words about your liver. Located under your right rib cage, the liver normally weighs about three pounds and is the body's second largest organ. (Your skin is the largest.) The liver is a complex organ that functions like a "chemical factory" processing many important body substances such as bile, digestive enzymes, clotting factors, cholesterol, and proteins. It is essential in the metabolism of fats, carbohydrates, proteins, and the various vitamins and minerals. It helps control the level of blood sugar and fats. It cleanses the blood and detoxifies drugs and potentially harmful chemicals such as alcohol. The liver is a storehouse for blood, vitamins and minerals, and glycogen - the stored form of sugar - the body's major fuel. The liver has an amazing ability to regenerate and replenish itself, but when disease strikes, this amazing factory can shut down and health problems occur. One such disease is Hepatitis A.
What Is Hepatitis A?
Hepatitis is a liver disease. In medical jargon, the word "hepatic" refers to the liver, like cardiac refers to the heart. The suffix "-itis" represents inflammation or infection as in sinusitis, appendicitis, tonsillitis, etc. So the word hepatitis means inflammation of the liver. Sometimes this is caused by a virus. In the 1970's, medical research revealed that this disease was caused by a specific virus and given the name Hepatitis A. So simply put, the disease called Hepatitis A is a viral infection of the liver caused by the Hepatitis A virus.
What Is a Virus?
A virus is a very small organism, invisible to all but the strongest microscopes. Unlike other living organisms, a virus cannot reproduce itself. Like a tiny parasite, it needs to take over the reproductive mechanism of other cells within the body, like liver cells. Once a virus invades a healthy liver cell, it reproduces quickly, eventually bursting the cell and scattering new virus particles into the bloodstream. These new viruses can then search out and invade more liver cells, repeating the process over and over. So, unchecked, a virus could rapidly spread throughout your body.
Your Immune System to the Rescue
Fortunately, your body's immune system has a very efficient type of "radar tracking" mechanism which allows identification and destruction of virus particles. Every time you get a virus, like a cold or flu, there is a fierce battle being waged in your body between the rapid formation of new virus particles and your immune system's ability to destroy them. Your immune system is pretty smart. It usually wins the battle and the infection is cured. In the case of Hepatitis A, the body usually wins, but the process takes time, usually several months.
What Are the Symptoms?
Most adults who contract Hepatitis A develop symptoms that usually occur suddenly and worsen over a period of several days. These often include loss of appetite, fatigue, nausea, vague stomach pain, darkening of the urine, and jaundice ( a yellowing of the skin and whites of the eyes ). Not everyone who is infected will have all of the symptoms.
Can You Have Hepatitis A and Not Know It?
Actually, yes if you have been recently exposed. The incubation period is the time that passes from when you first catch the virus until you develop symptoms. The average incubation period is 28 days, but ranges from 15 to 50 days. During this period, an exposed person may show no symptoms of illness, but the individual is contagious and spreading the virus. In addition, some adults and most children with this disease have no symptoms at all. But they are still contagious for a few weeks.
How Does Your Doctor Know?
Your symptoms or results from your doctor's examination cannot distinguish Hepatitis A from other forms of viral hepatitis. If your doctor suspects you may have Hepatitis A, he will usually order two types of blood tests.
One is a test for an antibody that shows the Hepatitis A virus is in your blood. This is called the IgM anti-HAV test. It is positive for infection a few weeks after exposure and about 5 - 10 days before symptoms occur. It will remain positive for about 6 months after the infection has cleared. This test need only be done once to make the diagnosis.
The second test is actually a series of 5 blood tests called a Hepatic Function Panel. This panel helps your doctor determine how much liver damage has occurred. The Hepatic Function Panel is usually repeated periodically for the duration of the illness. It helps your doctor verify that your liver is getting better and when it is back to normal.
About 80% of adults with Hepatitis A develop signs of jaundice - a temporary yellow discoloration of the urine, the whites of the eyes, and the skin. One reading that helps the doctor monitor the degree of jaundice is the level of the bilirubin in the blood. Bilirubin is a normal pigment found in the blood. It is normally filtered out by the liver. When the liver is sick, the bilirubin level in the blood often rises. Normally, the blood bilirubin level is less than one. With Hepatitis A, it usually goes much higher. However, as your liver gets better, the bilirubin level drops and the jaundice goes away.
Other blood tests in the liver panel monitor destruction of liver cells. Normally, a small percentage of the billions of cells within the liver die off each day and new cells are created. This process releases proteins called liver enzymes into the blood. Two most commonly requested blood tests are called ALT and AST. In cases of liver injury such as acute Hepatitis A, more liver cells die each day than normal, releasing higher amounts of these enzymes into the bloodstream. This causes an elevation in the ALT and AST enzyme readings. They may go quite high in the first several weeks, but drop back to normal as the infection is cleared.
It is important to follow your doctor's advice. You should keep all office appointments and have all the blood tests as requested. You should inform your doctor of any changes or worsening in your symptoms.
Who Is At Risk for Hepatitis A?
Unless you have already had this disease or been vaccinated, you are at risk. But compared to some illnesses, the general likelihood of contracting this disease is low. According to the Center for Disease Control (CDC), the following individuals are at highest risk:
- Persons who share a household or have sexual contact with someone who has Hepatitis A
- Travelers to countries where Hepatitis A is common and where clean water and proper sewage disposal are not available. Geographic areas with increased risk include: Asia, Africa, South America, Latin America, the Middle East, European countries bordering the Mediterranean, and Eastern European countries. Risk for HAV infection in these regions increases with duration of travel.
- Men who have anal sex with men
- Persons who use street drugs
- Children and employees in child care centers (especially centers that have children in diapers) where a child or an employee has Hepatitis A
- Residents and staff of institutions for developmentally disabled persons when a resident or an employee has Hepatitis A
- Workers who handle Hepatitis A infected animals or work with Hepatitis A virus in a research laboratory setting. (This does not include laboratories doing routine testing)
- Persons with clotting factor disorders who receive factor concentrates
How Is Hepatitis A Transmitted?
Hepatitis A is a contagious disease that spreads from person to person. It is not carried by animals or insects. To be frank, affected individuals must have eaten something that had been directly or indirectly contaminated with the feces (stool, bowel movements) of another affected individual. That is because Hepatitis A is mostly transmitted by the fecal-oral route. It enters through the mouth, multiplies in the liver and is passed in the feces. The virus can then be carried on an infected person's hands and can be spread by direct contact, or by consuming food or drink that has been handled by the individual. The Hepatitis A virus is highly contagious and the virus can survive on a surface (e.g. toys, cutting boards) for up to one month. A major problem is that a person with this disease is usually contagious before they know they are sick. They can spread the virus about one week before symptoms appear and during the first week of symptoms. Persons with no symptoms can still spread the virus. This often happens with young children who unknowingly spread Hepatitis A to older children and adults.
In addition to getting Hepatitis A directly from the infected people, you can get Hepatitis A by swallowing contaminated water or ice, eating raw shellfish harvested from sewage-contaminated water, or eating uncooked fruits, vegetables, or other food that may have become contaminated during handling. The Food and Drug Administration (FDA) has linked several epidemics to Mexican green onions which are layered and difficult to clean. Green onions and foods containing green onions should be cooked thoroughly to reduce or eliminate the risk of contracting Hepatitis A. The virus is killed by boiling for 1 minute. However, the disease can still be spread by cooked foods if they are contaminated after cooking. Adequate chlorination of water, as recommended in the United States, kills the Hepatitis A virus.
How Can Hepatitis A Be Prevented?
One way is good personal hygiene. Since this disease is spread from human to human by fecal contamination of food or utensils, careful bathroom hygiene is very important, especially for those that prepare food for others. Often outbreaks occur in restaurants where employees are not washing their hands well. Emphasis on careful hand washing, use of disposable gloves, and not working when ill are measures that can greatly minimize the risk of spreading hepatitis by food handlers. All of us should always wash our hands after using the bathroom, changing a diaper, and before eating and preparing food.
How About Family and Friends?
People with Hepatitis A can spread the virus to others who live in the same household or with whom they have sexual contact. Infected individuals should refrain from food preparation for others. Most doctors would suggest abstinence from sexual contact or exchange of body fluids until fully recovered. Casual contact as in the usual office, factory, or school setting, does not spread the virus.
The Public Health Department
Since Hepatitis A is a reportable disease, the doctor or laboratory must notify the local public health department of any new cases of Hepatitis A. It is the job of the health department to keep track of sporadic cases and look for patterns that may warn of a local outbreak in the community. Individuals with Hepatitis A may be contacted by their local health department regarding their exposure.
Is There A Vaccine for Hepatitis A?
Yes, a vaccine has been available since 1995 and it works very well. The vaccines currently licensed in the United States are HAVRIX (manufactured by SmithKline Beecham Biologicals) and VAQTA (manufactured by Merck & Co., Inc.). The vaccine is injected into the upper arm and is usually given twice with a second dose about 6 - 12 months after the first. Like the Salk-type inactivated polio vaccine, this vaccine is made of dead Hepatitis A viruses and is safe. It may cause a mild sore arm, but serious side effects have not been reported. There are no live viruses in Hepatitis A vaccine and it cannot transmit the disease itself. Rather, the vaccine tricks your immune system into thinking you are being attacked by large number of Hepatitis A viruses. Your body fights back by producing an antibody (IgG anti-HAV) that kills the virus - a process that take about 4 weeks. Once formed, this special antibody stays in your blood for a long time protecting you from this disease. The first dose is believed to provide about 97% protection. The second dose makes it closer to 100% and is felt to confer protection for at least 8 years. Estimates of antibody persistence derived from mathematical models of antibody decline indicate that protective levels of antibody could be present for as long as 20 years.
The Hepatitis A vaccine can be given to individuals 2 years of age and older, but must be given before exposure. Since the vaccine takes about 4 weeks to produce antibodies, it is not useful for those already exposed. It would not work in time. Interestingly, about 30% of adults already have protective levels of antibody from unrecognized childhood Hepatitis A infections. They are already immune to this disease, but don't know it. There is no harm in their receiving the vaccine.
Recently the FDA has approved TWINRIX (manufactured by SmithKline Beecham Biologicals), another inactivated vaccine for Hepatitis A protection. For use in adults only, TWINRIX is a combination vaccine against both Hepatitis A and B. Three injections over 6 months are required.
If I Travel Do I Need A Different Vaccine?
No. Unlike the common cold and other Hepatitis viruses, there seems to be only one common strain of Hepatitis A world-wide, so the vaccination is effective no matter what country you may visit in the future.
Who should receive Hepatitis A vaccine?
The U. S. Centers for Disease Control and Prevention (CDC) recommends Hepatitis A vaccine for:
travelers to countries with high rates of Hepatitis A
people living in communities with high rates of Hepatitis A
people in certain outbreak settings
laboratory personnel who work with Hepatitis A virus
men who have sex with men
susceptible people who have chronic liver disease
injecting drug users
The Hepatitis A vaccine may also be used in certain outbreak situations where ongoing transmission is occurring. Although studies of certain occupational groups (for example, food service workers, health care workers, child care workers, sewerage workers) have not shown an increased risk, such people may consider vaccination if they wish to further reduce their risk or are in communities where ongoing outbreaks are occurring. The vaccine works. In parts of the country where Hepatitis A vaccine is routinely given to children, infections rates have dropped almost 90%.
What If I Have Already Been Exposed?
Don't panic. For those who know or suspect that they have already been exposed to Hepatitis A, the vaccine won't help. But, there is another product called Immune Globulin which can help. It is a pre-made human antibody available for short-term prevention of the Hepatitis A virus infection. This injection delivers antibodies against Hepatitis A into the bloodstream and protects the individual almost immediately, but wears off in about 4 weeks. To be effective, Immune Globulin must be given within 2 weeks of exposure to the virus. When administered within this time frame, it is over 85% effective in preventing Hepatitis A. Immune Globulin is safe. No instance of transmission of other viruses has been observed with the use of Immune Globulin administered by the intramuscular route. Immune Globulin can be used at all ages and is safe during pregnancy and breast-feeding. Immune Globulin is often used in mass inoculations to limit community outbreaks of Hepatitis A.
How Is Hepatitis A Treated?
Unfortunately, like most viral diseases such as the common cold, no effective drug treatment is available for Hepatitis A. Patients simply have to get better on their own. Since this illness is caused by a virus, not a bacteria, antibiotics are not effective. Most cases can be treated as an outpatient with less than 15% requiring hospitalization. As with any viral illness, affected individuals should avoid unnecessary contact with others, get plenty of rest, and drink plenty of fluids. Since the stool remains very contagious for several weeks into the illness, they should be extra careful with bathroom hygiene. If possible, a separate bathroom should be set aside until recovery. Separating eating utensils may be of benefit.
Common sense tells us to avoid any other substances that could further damage the liver. These would include alcohol and Tylenol (acetaminophen). All alcohol should be avoided until recovery. Tylenol is often a problem. Tylenol in large doses can damage any liver. In acute Hepatitis A, even moderate doses may lead to liver failure and this drug should not be used. Unfortunately, since the early symptoms of Hepatitis A mimic those of influenza, many infected individuals begin taking Tylenol with the onset of fever and unknowingly worsen their condition. Aspirin and ibuprofen in recommended doses are safe.
The vast majority of individuals with Hepatitis A recover fully in about 4 - 6 weeks time. A typical adult case of Hepatitis A will result in about 27 lost days of work. About 10% of symptomatic cases have a prolonged waxing and waning illness that may last as long as 6 months. A very small percentage will develop complications that require liver transplant. It is estimated that the death rate for adults is about 27 per 1000 cases. Each year an estimated 100 persons die in the U.S. due to acute liver failure from Hepatitis A. Most are over the age of 50 or have some other underlying illness. Rarely, healthy young adults are stricken down.
Once in a Lifetime Experience
The good news is that once you recover from Hepatitis A, you are immune for life. Unlike the common cold, you cannot get this viral disease again. Lifelong immunity is provided by the IgG anti-HAV antibody your body produces in response to the infection.
Can Hepatitis A Become Chronic?
No. More good news. Unlike other forms of Viral Hepatitis (B, C), there is no chronic form of Hepatitis A. Once a person recovers from Hepatitis A, they do not continue to carry the virus and are not contagious.
If you have any unanswered questions about Hepatitis A, consult with your physician.