Hepatitis B virus (HBV) is the most common human hepatitis virus in Singapore.
Hepatitis B is an infection of the liver caused by a virus called Hepatitis B virus. It can cause an acute infection which sometimes results in the person becoming a carrier (ie. Persistent infection). Locally, 6% of the Singapore population are hepatitis B carriers. Those who test positive for hepatitis B for more than 6 months after the first test, are diagnosed as chronic. Having chronic hepatitis B increases your risk of developing liver failure, liver cancer or cirrhosis — a condition that permanently scars of the liver.
A vaccine can prevent hepatitis B, but there’s no cure if you have the condition. If you’re infected, taking certain precautions can help prevent spreading the virus to others.
1. Factors that have led Hepatitis B to become one of the biggest health threats in the Asia-Pacific region?
There are approximately 300 million chronic HBV carriers in the world, of whom 75% are found in the Asia Pacific region. Up to 50% of people who are newly infected have no symptoms. As the infection can lead to a chronic infection where majority of them have no symptoms, they are unaware that they are carriers and there can easily pass it to their partners and from mothers to their unborn child.
2. How does one get infected with Hepatitis B?
- Sex with an infected partner
- Injection drug use that involves sharing needles, syringes, or drug-preparation equipment
- Birth from an infected mother
- Contact with blood or open sores of an infected person
- Needle sticks or sharp instrument exposures
- Sharing items such as razors or toothbrushes with an infected person
Hepatitis B (HBV) does not spread through the sharing of food, water, utensils, breastfeeding, hugging, kissing, hand holding, coughing, or sneezing.
3. What are the symptoms of a Hepatitis B infection?
Newly acquired (acute) Hepatitis B (HBV) infections symptoms arise occasionally. The presence of signs and symptoms varies by age. Most children under age 5 years and newly infected immunosuppressed adults are generally asymptomatic, whereas 30%–50% of persons aged ≥5 years have signs and symptoms.
- Loss of appetite
- Abdominal pain
- Dark urine
- Clay-colored bowel movements
- Joint pain
Some acute HBV infections will resolve on their own, but some will develop into a chronic infection. Most people with a chronic HBV infection are asymptomatic and have no evidence of liver disease.
Approximately 90% of infants and 25%–50% of children aged 1–5 years will remain chronically infected with HBV. By contrast, approximately 95% of adults recover completely from HBV infection and do not become chronically infected.
4. How long does it take for the symptoms of Hepatitis B to show?
The symptoms appear an average of 90 days (range: 60–150 days) after exposure to HBV. If they develop yellowing of the whites of the eye, yellowing of the skin with vomiting, abdominal pain and drowsiness, they should seek medical attention as soon as possible.
5. If the symptoms are not obvious, how then would an infected person know?
Given the prevalence of chronic Hepatitis B carriers in our region, the best advice would be to go for a blood test to screen for Hepatitis B.
6. What are the dangers that one could face, if his or her Hepatitis B condition becomes chronic?
It may result in liver cirrhosis (hardening of the liver) or liver cancer.
7. How long before an infected person is deemed to have chronic Hepatitis B?
We will diagnose the person as a chronic Hepatitis carrier if the Hepatitis B surface antigen remains positive in their blood test result for 6 months or more.
8. How will a person be diagnosed, if he or she is suspected of being infected with Hepatitis B?
Through a blood test looking at the Hepatitis B surface antigen and Hepatitis B surface Antibodies; a Hepatitis B core antigen is used to distinguish active from past infection.
9. What is the difference between Hepatitis B surface antigen and Hepatitis B surface antibody?
A Hepatitis B antigen detects the actual part of the virus and the antibody detects the body’s immune response to that same part of the virus.
HBsAg will be detected in an infected person’s blood an average of 4 weeks (range: 1–9 weeks) after exposure to the virus. About 1 of 2 patients will no longer be infectious by 7 weeks after onset of symptoms, and all patients who do not remain chronically infected will be HBsAg-negative by 15 weeks after onset of symptoms.
10. What are some of the ways in which Hepatitis B is treated?
There is no specific treatment; only supportive care.
In many cases, chronic Hepatitis B carriers do not need treatment but they will require 6 month follow up with blood tests and/ or ultrasound liver for the rest of their lives. In cases where Hepatitis B carriers require treatment, the treatment may involve immune molecules or antiviral medications.
11. Can Hepatitis B be transmitted from an infected mother to her newborn? How can this be avoided?
Yes, mothers can transmit Hepatitis B to their newborn. The best way to avoid passing the infection to their newborn is to get tested for Hepatitis B when they are pregnant or prior to starting a family. If they are not being infected with Hepatitis B and are not immune to Hepatitis B, they should consider getting a vaccination.
12. If your child gets infected with Hepatitis B and is not treated, what are some of the problems that he or she could face for the rest of his or her life?
The risk of developing chronic HBV infection after acute exposure is about 90% in newborns of HBeAg-positive mothers and 25% of they may go on to develop liver cirrhosis and liver cancers in the future.
13. Prevention of Hepatitis B?
Hepatitis B is a vaccine-preventable disease. All sexual partners, family and close household members living with a chronically infected person should be tested and vaccinated.
14. Who should get the Hepatitis B vaccine?
- All infants
- Non-vaccinated children aged <19 years
- People at risk for infection by sexual exposure
- Sex partners of hepatitis B surface antigen (HBsAg)–positive persons
- Sexually active people who are not in a long-term, mutually monogamous relationship (e.g., persons with more than one sex partner during the previous 6 months)
- People seeking evaluation or treatment for a sexually transmitted infection
- Men who have sex with men
- People at risk for infection by percutaneous or mucosal exposure to blood
- Current or recent injection-drug users
- Household contacts of people who are HBsAg-positive
- Residents and staff of facilities for developmentally disabled people
- Health care and public safety personnel with reasonably anticipated risk for exposure to blood or blood-contaminated body fluids
- Hemodialysis patients and predialysis, peritoneal dialysis, and home dialysis patients
- People with diabetes aged 19–59 years; persons with diabetes aged ≥60 years at the discretion of the treating clinician
- International travelers to countries with high or intermediate levels of endemic hepatitis B virus (HBV) infection (HBsAg prevalence of ≥2%)
- People with hepatitis C virus infection
- People with chronic liver disease (including, but not limited to, persons with cirrhosis, fatty liver disease, alcoholic liver disease, autoimmune hepatitis, and an alanine aminotransferase [ALT] or aspartate aminotransferase [AST] level greater than twice the upper limit of normal)
- People with HIV infection
- People who are incarcerated
15. For people who have Hepatitis B, how does it impact their day to day activities and what are the best ways to cope?
For chronic Hepatitis B carriers, there are no major impacts on their day to day activities. They have to follow up with their doctors on a 6 month basis. They should, however, avoid alcohol because it can cause additional liver damage.
16. What are the signs showing that an infected person no longer has Hepatitis B?
For those who have acute Hepatitis B infection, if the HbsAg becomes negative after 6 months and they develop an immunity which will show on their HBsAb test, then it means they are cleared from the infection and are immune to the virus.
If you would like to find out more about Hepatitis B or C, come down to any of our clinics for a consultation.