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Hepatitis B is a contagious liver disease known as the "silent killer" because most people can be unaware of their infection for up to decades until it causes life-threatening diseases such as cirrhosis, liver cancer, and other severe complications. Fortunately, hepatitis B can be prevented by vaccination and spotted early through HBsAg blood tests. Read on to learn more about hepatitis B and its vaccination.
Hepatitis means ‘inflammation of the liver’. Hepatitis B is a viral infection caused by the hepatitis B virus (HBV) that attacks the liver. It’s a highly contagious disease. The World Health Organization estimates that 296 million people were living with chronic hepatitis B infection in 2019, with 1.5 million new infections each year.
Not everyone who is newly infected with HBV experiences symptoms, but those who do may experience fatigue, loss of appetite, stomach pain, nausea, and jaundice (yellow pigmentation of skin and eyes).
HBV is most commonly transmitted from mother to child during birth and delivery, as well as through contact with infected blood or other body fluids during unsafe (unprotected) sex, sharing injection needles, toothbrushes, or razors with an infected person.
Some infected patients will develop a chronic infection that may lead to serious or life-threatening liver problems such as cirrhosis or liver cancer. Fortunately, hepatitis B is a short-term illness for many people and is preventable by vaccination. Simple blood tests can diagnose hepatitis B infections, and there are effective drug therapies to manage hepatitis B infections.
Hepatitis B is often called a silent killer because many people do not experience any symptoms for up to decades before symptoms manifest. As a result, these asymptomatic HBV carriers are unaware that they are infected and can unknowingly spread the virus to others, continuing the silent spread of hepatitis B.
People who are chronically infected but do not show any symptoms are still suffering silent liver damage that can lead to serious liver diseases such as cirrhosis or liver cancer. When many people discover they are infected, it is already too late and they have developed serious liver complications as a result of the infection.
Hepatitis B is an infection caused by the hepatitis B virus (HBV). HBV is transmitted from an infected person's blood, sperm, and other bodily fluids into the body of a healthy person. Hepatitis B can also be passed down from mother to child during pregnancy or childbirth.
A healthy person can acquire HBV through these activities:
It is important to note that Hepatitis B is not transmitted through food or water, coughing, sneezing, or by casual contact including kissing, holding hands, hugging, or sharing kitchenware and utensils.
The following groups are at greater risk to become infected with HBV:
Nevertheless, the risk of chronic infection is highest in young children as the risk varies with the age of infection. Approximately 90% of infants and 25 to 50% of children aged 1–5 years with hepatitis B become chronically infected. In contrast, only 2 to 6% of adults who get hepatitis B develop chronic infection, while 95 percent of adults recover completely from HBV infection and do not become chronically infected.
If you are at high risk, your doctor can arrange for a blood test to check for hepatitis B and have the hepatitis B vaccination.
Not everyone who has an acute HBV infection experiences symptoms. The presence of signs and symptoms varies with age. In adults, HBV infection typically causes no obvious symptoms and usually passes in 1 to 3 months without treatment. This is known as acute hepatitis B, and it rarely causes serious complications.
Children, in particular, have a lower ability to fight HBV infection, which is why hepatitis B can persist for years and eventually cause serious liver damage. Most children under the age of 5 and newly infected immunosuppressed adults are generally asymptomatic, whereas 30 to 50% of people over the age of 5 have signs and symptoms.
If symptoms appear with acute infection, they usually appear within 3 months of HBV exposure and can last for several weeks, but can persist for up to 6 months.
Acute HBV infections can cause the following signs and symptoms when they are present:
Many of these symptoms can be mistaken for more common illnesses, such as the flu or gastroenteritis. A blood test must be performed to confirm HBV infection.
Chronic hepatitis B occurs when the infection lasts for six months or longer. Without treatment, people with chronic hepatitis B can develop complications like cirrhosis (scarring of the liver).
Hepatitis B is associated with many serious and deadly complications. Approximately 25% of people who become chronically infected during childhood and 15% of those who become chronically infected after childhood die prematurely from cirrhosis or liver cancer, and the majority of people are asymptomatic until cirrhosis or end-stage liver disease develops.
If left untreated or not fully treated, hepatitis B can lead to these diseases or complications, such as:
If you find yourself in these risk groups or suspect you might have hepatitis B, talk to your physician so you can be screened for hepatitis B. the doctor will ask you to provide a blood sample, which will be used to conduct the hepatitis B panel blood test.
The hepatitis B panel includes three parts to determine whether a patient has acute or chronic HBV infection, is immune to HBV as a result of prior infection or vaccination, or
is susceptible to infection and in need of vaccination. The three parts of the blood test results are:
It may take up to 6 months from the time of infection before a blood test can detect antibodies to hepatitis B, so follow-up testing may be required. During these 6 months, until you know whether you are infected or not, take precautions to avoid potentially infecting others.
When you are diagnosed with hepatitis B, you may need liver function tests or blood tests to assess liver damage caused by hepatitis B. These tests can be difficult to interpret, and specialist advice is required, so consult your doctor.
Although there is no cure for Hepatitis B, some drugs may help to control the disease's progression. Early diagnosis of hepatitis B can prevent the development of severe liver complications. Since hepatitis B is often asymptomatic, you should get tested for HBV and detect the virus quickly if you have not already been vaccinated.
Treatment for hepatitis B is determined by how long you have been infected. Since there is no medicine to treat acute hepatitis B, if you have only been infected for a few days, weeks, or months, you may only require supportive treatment to relieve your symptoms while your body fights off the infection. Make sure to have enough rest, adequate nutrition, and fluid intake. Otherwise, for more severe emergencies, hospitalized treatment can be given soon after possible HBV exposure (most effective within 48 hours, or have them up to a week after) to stop an infection, and it can be either:
Most people recover completely within a few months, but after the infection, regular blood tests are recommended to ensure that you are free of the virus and have not developed chronic hepatitis B.
If your infection has persisted for more than 6 months (chronic hepatitis B), you may need long-term or lifelong treatment with medicines that keep the virus under control and reduce the risk of liver damage.
Nevertheless, you may get vaccinated against hepatitis A and tested for hepatitis C.
Hepatitis B is a highly transmissible disease. Keep these in mind to prevent hepatitis B:
Other than the above measures, vaccination is the best way to avoid hepatitis B infection. Hepatitis B vaccines can provide excellent (98 to 100%) protection against hepatitis B. Preventing hepatitis B reduces the risk of complications such as chronic liver disease and liver cancer. It is advised for all infants, young children, and adolescents, as well as those in high-risk groups. There are a total of 3 doses administered for 6-18 months. Until the vaccine series is completed, follow the precautions outlined above points to avoid possible infection. Learn more about hepatitis B vaccines here.
Hepatitis B can be passed on to a baby during pregnancy or childbirth if the mother has it or is infected with it. The mother could become infected by the virus if she has sexual contact with an infected person, or if she comes into contact with infected blood.
In Hong Kong, Maternal and Child Health Centres (MCHCs) and hospitals under Hospital Authority provide a comprehensive shared-care program for expectant mothers, new mothers, and newborns. As part of her antenatal care, the mother should receive a hepatitis B blood test as well as checkups for other diseases or complications. Expectant mothers with high hepatitis B viral load should receive anti-viral treatment.
All children born in Hong Kong should be immunized against hepatitis B. The first dose is given in the hospital at birth, while the second and third doses are given in MCHCs. For babies born to carrier mothers, an additional hepatitis B immunoglobulin is given within 24 hours of birth to prevent transmission from their mothers. Vaccines are provided free of charge through Hong Kong Childhood Immunisation Programme.
Hepatitis B is most commonly acquired in areas of the world where the infection is more prevalent. Hepatitis B is found all over the world, but it is especially prevalent in:
The risk of contracting hepatitis B for travelers visiting areas where the infection is common is generally low if activities involving contact with blood or other bodily fluids are avoided.
If you do wish to travel (especially to the places mentioned above), you may consult your family doctor or the Hong Kong Travel Health Service. The Travel Health Service offers hepatitis B consultation and vaccination to international travelers who plan to visit high-risk areas of communicable diseases.
Hepatitis B vaccination is free for eligible children born in Hong Kong after 1988 as it is included in the Hong Kong Childhood Immunisation Programme. Those who have not received the vaccination may require blood test screening and vaccination.
The cost of hepatitis B tests and vaccination varies in different privacy settings and would be determined by doctor consultation fees, medication fees, laboratory tests, imaging test charges, etc. In Hong Kong, the cost of each dose of the hepatitis B vaccine ranges from $200 to $350. To complete the full vaccination schedule, three doses are required.
For inquiries and appointments, call the Family Planning Association of Hong Kong at 2919 7721.
For details, call the Travel Health Centres at 2961 8840 (Hong Kong) or 2150 7235 (Kowloon).
* All amounts are in HKD. No responsibility is accepted for any inaccuracies, errors, or omissions. It is always best to call ahead to make sure the information is still up-to-date.
Hepatitis B is a contagious liver disease known as the "silent killer" because most people can be unaware of their infection for decades until it causes life-threatening diseases such as cirrhosis, liver cancer, and other severe complications. Hepatitis B is caused by the hepatitis B virus infection. It is prevented by vaccination and avoiding contact with infected blood or bodily fluids.
Yes, hepatitis B can be spread through unprotected (unsafe) sex. To avoid hepatitis B, practice safe sex, use a condom, and avoid multiple sex partners. If you suspect you have hepatitis B, do a screening test.
Most adults with hepatitis B recover fully, even if their signs and symptoms are severe. Infants and children are more likely to develop a chronic (long-lasting) hepatitis B infection. Hepatitis B can be treated using antiviral medications.
HBsAg (Hepatitis B surface antigen): A ’positive’ or ’reactive’ HBsAg test result means that the person is infected with hepatitis B. It tests the actual presence of the hepatitis B virus via its surface antigen marker in your blood. A positive HBsAg test result means that you are infected and can spread the virus to others through your blood.
This article was independently written by Healthy Matters and is not sponsored. It is informative only and not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be relied upon for specific medical advice.
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