Hepatitis is inflammation of the liver. Infectious or viral hepatitis is caused by a viral infection. The three most common forms of viral hepatitis recognized to cause liver disease are hepatitis A, hepatitis B, and hepatitis C (previously called hepatitis non-A, non-B). Other recognized types of hepatitis are hepatitis D, hepatitis E, and hepatitis G.
Hepatitis A
Hepatitis A is an inflammation of the liver caused by the hepatitis A virus (HAV). It is usually not very severe, generally starting within two to six weeks after contact with the virus, and lasting no longer than two months.
Hepatitis A is commonly known as infectious hepatitis because it spreads relatively easily from those infected to their close contacts. Once the infection ends, there is no lasting, chronic phase of illness. However, it is not uncommon to have a second episode of symptoms about a month after the first (a relapse).
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Epidemics of HAV infection can infect dozens and even hundreds of persons. Major outbreaks of hepatitis A have been linked to infected food handlers contaminating prepared foods. Many types of food also can be infected by sewage containing HAV, and shellfish are a common culprit.
Certain groups have an increased risk of contracting hepatitis A. These include:
- children and employees at daycare centers
- individuals living in crowded and/or unsanitary conditions
- sexually active individuals
- tourists visiting an area where hepatitis A is common
Hepatitis B
More than 300 million people throughout the world are infected by the hepatitis B virus (HBV). Hepatitis B occurs in both rapidly developing (acute) and long-lasting (chronic) forms, and is one of the most frequent chronic infectious diseases worldwide. Commonly called “serum hepatitis,” hepatitis B ranges from mild to very severe. Some people who are infected by HBV develop no symptoms, but they may carry HBV in their blood and pass the infection on to others. In its chronic form, HBV infection may destroy the liver through a scarring process called cirrhosis.
When a person is infected by HBV, the virus enters the bloodstream and body fluids, and is able to pass through tiny breaks in the skin, mouth, or the genital area. This infection can occur during birth, when a mother with hepatitis B may pass HBV on to her infant. The virus also may be transmitted through contaminated needles and through unprotected sex with an HBV infected individual. Casual contact cannot transmit hepatitis B.
Hepatitis C
Hepatitis C, or HCV, causes a rapidly developing and often long-lasting disease. Spread mainly by contact with infected blood, HCV is the major cause of “transfusion hepatitis,” which can develop in patients who are given blood, although, donated blood is regularly tested for hepatitis C as of the early 2000s. The existence of a third hepatitis virus (in addition to the A and B viruses) became clear in 1974, although HCV was first identified in 1989.
Hepatitis C is generally mild in its early, acute stage, but it is much more likely to produce chronic liver disease than hepatitis B. About two of every three persons who are infected by HCV may continue to have the virus in their blood and become carriers who can transmit the infection to others.
The most common way of transmitting hepatitis C is when blood containing the virus enters another person’s bloodstream through a break in the skin or the mucosa (inner lining) of the mouth or genitals. HCV may be passed from an infected mother to the infant she is carrying (however, the risk of infection from breast milk is very low). It also can be spread through sexual intercourse, especially if one partner is acutely infected at the time.
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Hepatitis D
Hepatitis D (or delta), occurs only in patients who also are infected by the hepatitis B virus. Infection by the hepatitis delta virus (HDV) either occurs at the same time as hepatitis B, or develops later when infection by HBV has entered the chronic stage.
Delta hepatitis can be quite severe, but is seen only in patients already infected with HBV. In the late 1970s Italian physicians discovered that some patients with hepatitis B had another type of infectious agent in their liver cells. Later the new virus, HDV, was confirmed by experimentally infecting chimpanzees. When both viruses are present, acute infection tends to be more serious. Furthermore, patients with both infections are more likely to develop chronic liver disease than those with HBV alone, and, when it occurs, it is more severe.
Hepatitis E
Hepatitis E also is known as epidemic non-A, non-B hepatitis. Like hepatitis A, it is an acute and short-lived illness that sometimes can cause liver failure. HEV, discovered in 1987, is spread by the fecal-oral route. It is present in countries in which human waste has contaminated the drinking water supply. Large outbreaks (epidemics) have occurred in Asian and South American countries where there is poor sanitation. In the United States and Canada no outbreaks have been reported, but persons traveling to a region where it is present may return with HEV.
Hepatitis G
HGV, also called hepatitis GB virus, was first described in early 1996. Little is known about the frequency of HGV infection, the nature of the illness, or how to prevent it. What is known is that transfused blood containing HGV has caused some cases of hepatitis.
For this reason, patients with hemophilia and other bleeding conditions who require large amounts of blood or blood products are at risk of constructing hepatitis G. HGV has been identified in 1–2% of blood donors in the United States. Also at risk are patients with kidney disease who undergo hemodialysis treatments, and those who inject intravenous drugs. It is possible that an infected mother can pass on the virus to her newborn infant, or that sexual transmission can occur.
Often patients with hepatitis G are infected at the same time by the hepatitis B or C virus, or both. In about three of every thousand patients with acute viral hepatitis, HGV is the only virus present. There is some indication that patients with hepatitis G may continue to carry the virus in their blood for many years, and so might be a source of infection for others.
Causes & symptoms
Hepatitis A
The time between exposure to HAV and the onset of symptoms ranges from two to seven weeks and averages about one month. The virus is passed in the feces, especially late in the incubation period, before symptoms first appear. The virus can live for several hours on the skin surface, and during this time may be transmitted to others. Infected persons are most contagious starting about a week before symptoms develop, and remain contagious until the time jaundice (yellowing of the skin and/or eyes) is noted.
Often the first symptoms to appear are fatigue, muscle and joint aches, nausea, and a loss of appetite. Lowgrade fever is common, and the liver often enlarges, causing pain or tenderness in the upper right part of the abdomen. Jaundice then develops, typically lasting seven to ten days.
Hepatitis B
In the United States, a majority of acute HBV infections occur in teenagers and young adults. Half of these youth never develop symptoms, and only about 20% of infected patients develop severe symptoms and jaundice. The remaining 30% of patients have only flu-like symptoms and will probably not even be diagnosed as having hepatitis unless certain tests are done. Acute hepatitis B is characterized by loss of appetite, nausea, and pain or tenderness in the right upper part of the abdomen. Compared to patients with hepatitis A or C, those with HBV infection require more bed rest.
An HBV infection lasting longer than six months is said to be chronic. After this time it is much less likely for the infection to disappear. Not all carriers of the virus develop chronic liver disease; in fact, most have no symptoms. However, about one in every four HBV carriers develop cirrhosis. Patients are also likely to have an enlarged liver and spleen. The most serious complication of chronic HBV infection is liver cancer.
Hepatitis C
More than half of all patients who develop hepatitis C have no symptoms or signs of liver disease. Some, however, may have a minor illness with flu-like symptoms. About one in four patients with hepatitis C will develop jaundice, and some patients lose their appetite and frequently feel tired. Patients also may experience nausea.
In most patients, HCV can still be found in the blood six months after the start of acute infection, and these patients are considered carriers. If the virus persists for one year, it is unlikely to disappear completely. About 20% of chronic carriers develop cirrhosis (scarring) of the liver when the virus damages or destroys large numbers of liver cells, which are then replaced by scar tissue. Cirrhosis may develop only after a long period of time—as long as 20 years—has passed. Many patients will not develop cirrhosis and instead have a mild, chronic form of infection called chronic persistent hepatitis.
Hepatitis D
The delta virus is a small and incomplete viral particle. Perhaps this small size is why it cannot cause infection on its own. Its companion virus, HBV, actually forms a covering over the HDV particle. In chronically ill patients (those whose virus persists longer than six months), cirrhosis typically occurs.
When HBV and HDV infections develop at the same time—a condition called coinfection—recovery is the rule. Only 2–5% of patients become chronic carriers (the virus remains in their blood more than six months after infection). It may be that HDV actually keeps HBV from reproducing as rapidly as it would if it were alone, making chronic infection less likely.
When HBV infection occurs first and is followed by HDV infection, the condition is called superinfection. Between one-half and two-thirds of patients with superinfection develop severe acute hepatitis. Once the liver cells contain large numbers of HBV viruses, HDV tends to reproduce more actively. Massive infection and liver failure are more common in superinfection. The risk of liver cancer, however, is no greater than from hepatitis B alone.
As with other forms of hepatitis, the earliest symptoms are nausea, loss of appetite, joint pains, and fatigue. There may be fever and an enlarged liver may cause discomfort or pain in the right upper part of the abdomen. Jaundice may develop later.
Hepatitis E
There are at least two strains of HEV, one found in Asia and another in Mexico. The virus may start dividing in the gastrointestinal tract, but it grows mostly in the liver. After an incubation period of two to eight weeks, infected persons develop jaundice, fever, nausea, a loss of appetite, and discomfort or pain in the right upper part of the abdomen. Most often the illness is mild and disappears within a few weeks with no lasting effects.
Hepatitis E never becomes a chronic illness, but on rare occasions the acute illness damages and destroys so many liver cells that the liver can no longer function. This is called fulminant liver failure, and may end in death. The great majority of patients who recover from acute infection do not continue to carry HEV and cannot pass the infection on to others.
Hepatitis G
Some researchers believe that there may be a group of GB viruses, rather than just one. Others remain doubtful that HGV actually causes illness. If it does, the type of acute or chronic illness that results is not clear. When diagnosed, acute HGV infection has usually been mild and brief. There is no evidence of serious complications, but it is possible that, like other hepatitis viruses, HGV can cause severe liver damage resulting in liver failure. The virus has been identified in as many as 20% of patients with longlasting viral hepatitis, some of whom also have hepatitis C.
Diagnosis
A health care professional will conduct a thorough medical history and physical examination of the patient when hepatitis is suspected. Blood tests for specific antigens and antibodies that are present in the different subtypes of hepatitis will confirm the diagnosis, although these tests cannot detect all types of hepatitis. Liver function tests that measure enzyme levels may also be performed.
Treatment
Once symptoms appear, no antibiotics or other medicines will shorten the course of infectious hepatitis. Patients should rest in bed as needed, follow a healthy diet, and avoid drinking alcohol or taking any medications that could further damage the liver. Any medication that can cause liver damage should be avoided, and non-critical surgery should be postponed.
An herbalist or naturopathic health care professional may recommend a preparation of milk thistle (Silybum marianum) for the treatment of hepatitis. Milk thistle is thought to promote the growth of new liver cells, and to prevent toxins from penetrating through healthy liver cells by binding itself to the cell membranes. It is frequently prescribed by herbalists for the treatment of cirrhosis, hepatitis, and other liver disorders.
A large controlled trial sponsored by the National Center for Complementary and Alternative Medicine (NCCAM) and the National Institutes of health (NIH) on milk thistle’s medicinal value in the treatment of hepatitis and liver injury was scheduled to begin in the year 2000. Licorice (Glycyrriza glabra) may also be used for hepatitis. Its properties include protecting the liver and enhancing the immune system. Extended use of licorice should not be undertaken without medical consultation, since potassium deficiency may result.
Vitamin C may be taken as a nutritional supplement. It has been shown to help diminish acute hepatitis and help prevent hepatitis in hospitalized patients. Liver extracts are effective in liver regeneration, and have been used for over a century. Thymus extracts enhance the immune system, which may help the body fight a hepatitis virus.
A practitioner of Chinese herbal medicine may recommend Fructus Schisandrae Chinensis, which improves liver function; Fructus Citrulli Vulgaris, which helps to expel jaundice; or other herbs for hepatitis symptoms.
Allopathic treatment
A natural body protein, interferon alpha, now can be made in large amounts by genetic engineering, and improves the outlook for many patients who have chronic hepatitis C. The protein can lessen the symptoms of infection and improve liver function. In 2003, a synthetic analogue was added to improve the treatment’s effectiveness. Fever and flu-like symptoms are frequent side effects of this treatment. Approximately one-half of patients respond positively to the treatment, although only about 20% receive lasting effects. Several new treatment drugs have been tested and found beneficial in suppressing hepatitis B since early 2003. One of these drugs also helps those patients infected with both hepatitis B and HIV.
When hepatitis destroys most or all of the liver, the only hope may be a liver transplant. However, even when the procedure is successful, disease often recurs and cirrhosis may actually develop more rapidly than before.
Expected results
Hepatitis A
Most patients with acute hepatitis A, even when severe, begin feeling better in two to three weeks, and recover completely in four to eight weeks. After recovering from hepatitis A, a person no longer carries the virus and remains immune for life. In the United States, serious complications are infrequent and deaths are rare. In the United States, as many as 75% of adults over the age of 50 will have blood test evidence of previous hepatitis A.
Hepatitis B
Each year an estimated 150,000 persons in the United States get hepatitis B. More than 10,000 will require hospital care, and as many as 5,000 will die from complications of the infection. About 90% of those infected will have only acute disease. A large majority of these patients will recover within three months.
It is the remaining 10% with chronic infection who account for most serious complications and deaths from HBV infection. In the United States, perhaps only 2% of all infected will become chronically ill. People infected with both HIV and hepatitis B are most likely to die than from either disease alone. Even when no symptoms of liver disease develop, chronic carriers remain a threat to others by serving as a source of infection.
Hepatitis C
In roughly one-fifth of patients who develop hepatitis C, the acute infection will subside, and they will recover completely within four to eight weeks and have no later problems. Other patients face two risks: they themselves may develop chronic liver infection and possibly serious complications such as liver cancer, and they will continue carrying the virus and may pass it on to others.
The overall risk of developing cirrhosis is about 15% for all patients infected by HCV. Liver failure is less frequent in patients with chronic hepatitis C than it is for those with other forms of hepatitis. In those people who also have AIDS, hepatitis C infection increases the chance for liver cancer.
Hepatitis D
A large majority of patients with coinfection of HBV and HDV recover from an episode of acute hepatitis. However, about two-thirds of patients chronically infected by HDV go on to develop cirrhosis of the liver. If severe liver failure develops, the chance of a patient surviving is no better than 50%. A liver transplant may improve this figure to 70%.
Hepatitis E
In the United States hepatitis E is not a fatal illness, but elsewhere 1–2% of those infected die of advanced liver failure. In pregnant women the death rate is as high as 20%. It is not clear whether having hepatitis E once guarantees against future HEV infection.
Hepatitis G
What little is known about the course of hepatitis G suggests that illness is mild and does not last long. When more patients have been followed up after the acute phase, it will become clear whether HGV can cause severe liver damage.
Prevention
The best way to prevent any form of viral hepatitis is to avoid contact with blood and other body fluids of infected individuals. The use of condoms during sex also is advisable. Travelers should avoid water and ice if unsure of their purity, or they can boil water before drinking it. All foods eaten should be packaged, well cooked, or, in the case of fresh fruit, peeled.
Caution should be exercised when getting tattoos or body piercing, since a 2003 report said that only about one-half of tattoo and piercing shops follow the government’s guidelines concerning infection control. These practices can pass hepatitis and HIV infection.
There are vaccines available for both hepatitis A and hepatitis B. Individuals in a high-risk group and travelers should be vaccinated for hepatitis A, and much of the general population can be vaccinated for hepatitis B.
