Hepatitis B Test

Hepatitis B Test in Shanghai


Also known as: HBV; Hep B; anti-HBs; Hepatitis B surface antibody; HBsAg; Hepatitis B surface antigen; HBeAg; Hepatitis B e antigen; anti-HBc; Hepatitis B core antibody; anti-HBc, IgM; anti-HBe; Hepatitis B e antibody; HBV DNA. Formal name: Hepatitis B Virus. For only $150 dollars you'll receive a Confidential Hepatitis B Test at a National Laboratory in Shanghai.

Hepatitis B Fact

Key facts

  • Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease.
  • The virus is transmitted through contact with the blood or other body fluids of an infected person - not through casual contact.
  • About 2 billion people worldwide have been infected with the virus and about 350 million live with chronic infection. An estimated 600 000 persons die each year due to the acute or chronic consequences of hepatitis B.
  • About 25% of adults who become chronically infected during childhood later die from liver cancer or cirrhosis (scarring of the liver) caused by the chronic infection.
  • The hepatitis B virus is 50 to 100 times more infectious than HIV.
  • Hepatitis B virus is an important occupational hazard for health workers.
  • Hepatitis B is preventable with a safe and effective vaccine.

Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus. It is a major global health problem and the most serious type of viral hepatitis. It can cause chronic liver disease and puts people at high risk of death from cirrhosis of the liver and liver cancer. 

Worldwide, an estimated two billion people have been infected with the hepatitis B virus (HBV), and more than 350 million have chronic (long-term) liver infections.

A vaccine against hepatitis B has been available since 1982. Hepatitis B vaccine is 95% effective in preventing HBV infection and its chronic consequences, and is the first vaccine against a major human cancer.

Symptoms

Hepatitis B virus can cause an acute illness with symptoms that last several weeks, including yellowing of the skin and eyes (jaundice), dark urine, extreme fatigue, nausea, vomiting and abdominal pain. People can take several months to a year to recover from the symptoms. HBV can also cause a chronic liver infection that can later develop into cirrhosis of the liver or liver cancer.

Who is most at risk for chronic disease?

The likelihood that an HBV infection will become chronic depends upon the age at which a person becomes infected, with young children who become infected with HBV being the most likely to develop chronic infections. About 90% of infants infected during the first year of life develop chronic infections; 30% to 50% of children infected between one to four years of age develop chronic infections. About 25% of adults who become chronically infected during childhood die from HBV-related liver cancer or cirrhosis.

About 90% of healthy adults who are infected with HBV will recover and be completely rid of the virus within six months.

Where is hepatitis B most common?

Hepatitis B is endemic in China and other parts of Asia. Most people in the region become infected with HBV during childhood. In these regions, 8% to 10% of the adult population are chronically infected.  Liver cancer caused by HBV is among the first three causes of death from cancer in men, and a major cause of cancer in women. High rates of chronic infections are also found in the Amazon and the southern parts of eastern and central Europe. In the Middle East and Indian sub-continent, an estimated 2% to 5% of the general population is chronically infected. Less than 1% of the population in western Europe and North American is chronically infected.

Transmission

Hepatitis B virus is transmitted between people by contact with the blood or other body fluids (i.e. semen and vaginal fluid) of an infected person. Modes of transmission are the same for the human immunodeficiency virus (HIV), but HBV is 50 to 100 times more infectious Unlike HIV, HBV can survive outside the body for at least 7 days. During that time, the virus can still cause infection if it enters the body of a person who is not infected.

Common modes of transmission in developing countries are:

  • perinatal (from mother to baby at birth)
  • early childhood infections (inapparent infection through close interpersonal contact with infected household contacts)
  • unsafe injections practices
  • blood transfusions
  • sexual contact

In many developed countries (e.g. those in western Europe and North America), patterns of transmission are different than those mentioned above. Today, the majority of infections in these countries are transmitted during young adulthood by sexual activity and injecting drug use. HBV is a major infectious occupational hazard of health workers.

HBV is not spread by contaminated food or water, and cannot be spread casually in the workplace.

The virus incubation period is 90 days on average, but can vary from about 30 to 180 days. HBV may be detected 30 to 60 days after infection and persist for widely variable periods of time.

Treatment

There is no specific treatment for acute hepatitis B. Care is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhoea.

Chronic hepatitis B can be treated  with drugs, including interferon and anti-viral agents, which can help some patients. Treatment can cost thousands of dollars per year and is not available to most patients in developing countries.

Liver cancer is almost always fatal, and often develops in people at an age when they are most productive and have family responsibilities. In developing countries, most people with liver cancer die within months of diagnosis. In higher income countries, surgery and chemotherapy can prolong life for up to a few years in some patients.

Patients with cirrhosis are sometimes given liver transplants, with varying success.

Prevention

All infants should receive the hepatitis B vaccine: this is the mainstay of hepatitis B prevention. 

The vaccine can be given as either three or four separate doses, as part of existing routine immunization schedules. In areas where mother-to-infant spread of HBV is common, the first dose of vaccine should be given as soon as possible after birth (i.e. within 24 hours). 

The complete vaccine series induces protective antibody levels in more than 95% of infants, children and young adults. After age 40, protection following the primary vaccination series drops below 90%. At 60 years old, protective antibody levels are achieved in only 65 to 75% of those vaccinated. Protection lasts at least 20 years and should be lifelong.

All children and adolescents younger than 18 years old and not previously vaccinated should receive the vaccine.  People in high risk groups should also be vaccinated, including:

  • persons with high-risk sexual behaviour;
  • partners and household contacts of HBV infected persons;
  • injecting drug users;
  • persons who frequently require blood or blood products;
  • recipients of solid organ transplantation;
  • those at occupational risk of HBV infection, including health care workers; and
  • international travellers to countries with high rates of HBV.

The vaccine has an outstanding record of safety and effectiveness. Since 1982, over one billion doses of hepatitis B vaccine have been used worldwide. In many countries where 8% to 15% of children used to become chronically infected with HBV, vaccination has reduced the rate of chronic infection to less than 1% among immunized children.

As of December 2006, 164 countries vaccinate infants against hepatitis B during national immunization programmes - a major increase compared with  31 countries in 1992, the year that the World Health Assembly passed a resolution to recommend global vaccination against hepatitis B.

Why Get Tested?

To detect, diagnose, and/or follow the course of an infection with hepatitis B virus (HBV) or to determine if the vaccine against hepatitis B has produced the desired level of immunity

When to Get Tested?

If you have symptoms of a hepatitis B infection or are likely to have been exposed to the hepatitis B virus; if you have chronic liver disease due to some other cause; if you have received the hepatitis B vaccine; if you are being treated for HBV

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?

None

Test Sample

What is being tested?

Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). It is one of several various causes of hepatitis, a condition characterized by inflammation and enlargement of the liver. Other causes of hepatitis include, for example, certain drugs, inherited disorders, and autoimmune diseases. HBV is one of five "hepatitis viruses" identified so far. The other four are A, C, D, and E.

HBV is the most common cause of acute hepatitis and the most widespread cause of chronic viral infections worldwide (although hepatitis C virus is a more common cause in most of North America and Europe). According to the CDC, there were about 43,000 new cases of hepatitis B in 2007 in the U.S. However, that number is only an estimate; the actual number of cases that were reported was much lower because many people have few or mild symptoms and never know they have the disease. The chronic form of hepatitis B continues to be a problem in the U.S. with about 800,000 to over 1 million people affected. Worldwide, it is thought to affect about 350 million people and to be a factor in the death of about 620,000 each year.

HBV is spread through contact with blood or other body fluids from an infected person. Exposure can occur, for example, through sharing of needles for IV drug use or through unprotected sex. People who live in or travel to areas of the world where hepatitis B is prevalent are at a greater risk. Mothers can pass the infection to their babies, usually during or after birth. The virus, however, is not spread through food or water, casual contact such as holding hands, or coughing or sneezing.

The course of HBV infections can vary from a mild form that lasts only a few weeks to a more serious chronic form lasting years. Sometimes chronic HBV leads to serious complications such as cirrhosis or liver cancer. Some of the various stages or forms of hepatitis B include:

  • Acute infection - presence of typical signs and symptoms with positive screening test
  • Chronic infection — persistent infection with the virus detected by lab tests accompanied by inflammation of the liver
  • Carrier (inactive) state — persistent infection but no liver inflammation (a carrier is someone who may appear to be in good health but harbors the virus and can potentially infect others) "Cleared" infection — no longer any evidence of infection;

viral antigen and DNA tests are negative and no signs or symptoms of liver inflammation (although, in many cases, the virus is present in an inactive state in the liver) The signs and the symptoms of an acute hepatitis B infection can be very similar to those of other types of acute hepatitis. Some of these include fever, tiredness, nausea, vomiting, and jaundice. With hepatitis, the liver is damaged and is not able to function normally. It cannot process toxins or waste products such as bilirubin for their removal from the body. During the course of disease, bilirubin and liver enzyme levels in the blood may increase. While tests such as bilirubin or a liver panel can tell your doctor that you have hepatitis, they will not indicate what is causing it. Tests that detect infection with a hepatitis virus may help determine the cause.

There are several different tests that can be used to detect current or previous HBV infection. Some of the tests detect antibodies produced in response to HBV infection; some detect viral antigens while others detect viral DNA. They can be used to screen for infection in the absence of symptoms, to determine whether infection is acute or chronic, or to monitor a chronic infection.

Though a potentially serious infection, acute HBV infection usually resolves on its own in most adults. Infants and children tend to develop a chronic infection more often. A vaccine is available to help prevent hepatitis B. Since routine vaccination of children was implemented in 1990, the cases of acute hepatitis B have decreased by about 82%, according to the CDC.

How is the sample collected for testing?

A blood sample is drawn by needle from a vein in the arm.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed.

The Test

How is it used?

Hepatitis B tests may be used for a variety of reasons. Some of the tests detect antibodies produced in response to HBV infection; some detect antigens produced by the virus, and others detect viral DNA.

Generally, one set of tests is used to determine the cause of acute symptoms while another set of tests may be used after a diagnosis is made, to monitor possible progression of the disease, to detect chronic infection and/or carrier status.

The items below list the main uses for HBV tests:

  • To detect acute hepatitis B infection: hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), IgM and sometimes hepatitis B e antigen (HBeAg)
  • To diagnose chronic HBV hepatitis: HBsAg, hepatitis B virus (HBV) DNA, and sometimes HBeAg
  • To monitor chronic hepatitis B infection and its treatment: HBsAg, hepatitis B e antigen (HBeAg), hepatitis B surface antibody (anti-HBs) IgG, hepatitis B e antibody (anti-HBe) IgG and HBV DNA
  • To detect previous exposure to hepatitis B, in a person who is immune compromised (when the virus can become reactivated): hepatitis B core antibody (anti-HBc) total and anti-HBs

Some of the secondary reasons to perform testing include: to screen for hepatitis B infection in at-risk populations or in blood donors, to determine if someone is a carrier, to detect previous infection (with subsequent immunity), and to determine if immunity has developed due to vaccination.

Some of the tests used to screen for infection may be performed as part of an acute viral hepatitis panel in conjunction with tests for other hepatitis viruses, including hepatitis A (HAV) or hepatitis C (HCV).

The following table summarizes the various hepatitis B tests and their use (save to see the big picture):

Hepatitis-B 

While the tests described above are specific for HBV, other liver tests such as AST, ALT, and gamma-glutamyl transferase (GGT) may be used to monitor the progress of the disease. In some cases, a liver biopsy may be performed for confirmation.

When is it ordered?

Hepatitis B tests may be ordered when someone has signs and symptoms associated with acute hepatitis to determine if they are due to infection with HBV. Some of these include:

  • Fever
  • Fatigue
  • Loss of appetite
  • Nausea, vomiting
  • Abdominal pain
  • Dark urine
  • Pale stools
  • Joint pain
  • Jaundice

Hepatitis B tests may be done as follow up when routine tests results such as ALT and/or AST are elevated. Sometimes acute forms of hepatitis may be detected this way since they may cause only mild symptoms that can be confused with the flu. Chronic hepatitis more often has no symptoms and is more commonly detected when routine test results are abnormal.

A test for hepatitis B surface antigen (HBsAg) may be used for screening when someone falls into one of the high-risk categories for chronic hepatitis B. In September 2008, the CDC revised it guidelines and recommends the following groups be tested for HBsAg:

  • People who are possible source of infection through accidental cuts, needlesticks, etc. in health care workers
  • People born in areas of the world that have a greater than 2% prevalence of HbsAg (for example, much of Asia and Africa)
  • People born in the US but were not vaccinated and whose parents are from an area with greater than 8% prevalence of HbsAg
  • Men who have sex with men
  • People who have elevated liver enzymes (ALT and AST) with no known cause
  • People with certain medical conditions that require that their immune system be suppressed
  • Pregnant women
  • People who are in close contact with someone infected with HBV
  • Those infected with HIV

In addition, some states in the US recommend that people who are in contact with the public and who are a possible source of infection through accidental cuts, scrapes, etc. be screened.

When hepatitis B tests are used to monitor people with chronic hepatitis B infections, they may be performed on a regular basis. Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) are usually measured about every 6 months to a year, since in some people HBeAg (and, less commonly, HBsAg) will go away on their own. In those who are being treated for chronic HBV, HBeAg and HBV DNA can be used to determine whether the treatment is successful. HBV DNA will fall, usually to undetectable levels, with successful treatment. If HBeAg was positive before treatment and becomes negative, then treatment may sometimes be stopped after a further period of treatment, and both it and HBV DNA may remain undetectable. If HBeAg was negative before treatment or remains positive, then treatment is usually continued.

All donated blood is tested for the presence of the HBsAg before being distributed for transfusion.

What does the test result mean?

The tests for hepatitis B may be ordered individually, but are often ordered in some combination depending on the reason for testing. Results of the tests are typically evaluated together. Sometimes the meaning of one result depends on the result of another test. However, not all tests are done on all people. Ask you doctor what she expects to find out from the results of your tests. She can help you understand what the results mean.

The table below summarizes possible interpretations of some common patterns of results. (save to see the big picture)

hepb2

*Note: There are some types (strains) of HBV that do not make e-antigen. In areas where these strains of HBV are common (in the Middle East and Asia), testing for HBeAg is not very useful. In these cases, a negative HbeAg result does not necessarily mean that the antigen is not present or that the person is not infectious; it may be that the person is infected with a strain that does not make the e-antigen.

Hepatitis B viral (HBV) DNA: This test measures the amount of virus present in the blood, so results are reported as numbers, specifically, as "international units per milliliter." A high result usually means that the virus is actively replicating and that the infection can be passed to others. It also indicates that the person has a high risk of having liver damage.

A low result or one that is reported as below a lower limit (for example, 100 international units/milliliter) means the virus is not present or is present in such low numbers that it cannot be detected. This usually means that the infection cannot be spread to others. If the test is used to monitor treatment, a low result usually indicates the therapy is effective.

Is there anything else I should know?

Even if you don't have symptoms, an HBV infection can damage your liver and you can spread the infection to others. For this reason, it is important to get tested if you think you have been exposed to HBV.

Hepatitis D (HDV) is another virus that can cause liver infections, but only if hepatits B is also present. A person may become infected with both viruses at the same time (a co-infection) or may first be infected with hepatitis B and then become infected with HDV (a superinfection). In the U.S., the incidence of HDV is low. There is no vaccine for HDV, but since it causes infections only in the presence of HBV, it may be prevented with the HBV vaccine.

The hepatitis panel we offer for Hepatitis B is available for $XXX. It takes 3 to 6 months after exposure to develop hepatitis antibodies. Results usually return in 3 to 5 days.

Tattoos? Unsure of your exposure? Take Control.

send email This email address is being protected from spambots. You need JavaScript enabled to view it.  to speak to one of our counselors to schedule your test today in Shanghai.

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