Hepatitis B

Organism

Hepatitis B is an infectious disease caused by the hepatitis B virus (HBV) that primarily affects the liver. HBV is mainly spread through direct contact with infected blood and blood products but can be sexually transmitted. 

Clinical presentation
Acute hepatitis B virus (HBV) infection may be asymptomatic or may present with the following symptoms: 
  • right upper quadrant pain,
  • lethargy, 
  • nausea, 
  • fever, 
  • anorexia for a few days then jaundice, 
  • pale stools and dark urine. 

The incubation period is 45-180 days (mean: 60 days)

In some cases of HBV infection, the virus will not be eliminated and the person will become chronically infected (i.e.HBsAg or HBV DNA (PCR) has been detected on two occasions at least 6 months apart). Chronic HBV infection is commonly asymptomatic. However, there is no such thing as a healthy carrier. Even if they appear to be healthy, people with chronic HBV should be monitored regularly (every 6-12 months) by their GP for signs and symptoms of liver disease.

Chronic HBV (CHB) infection is usually asymptomatic until the patient has progressed to cirrhosis (liver damage and scarring). Symptoms of cirrhosis include:

  • jaundice
  • ankle swelling,
  • ascites,
  • GI bleeding,
  • Encephalopathy

There are four phases of CHB:

  • Immune tolerance
  • Immune clearance
  • Immune control
  • Immune escape

 

The patient’s immune response in each phase determines the outcome of infection and the severity of cirrhosis which is caused by the immune response rather than the hepatitis B virus (HBV) itself. Progression to cirrhosis is most likely during the immune clearance and immune escape phases; treatment should be considered for patients in these phases, see Treatment.

People with cirrhosis due to chronic HBV are at increased risk of developing hepatocellular carcinoma.

People with chronic HBV may transmit infection vertically (from mother to baby), or through sexual or percutaneous exposure.

Investigations

Laboratory investigations of HBV infection include:

  • tests to diagnose HBV infection.
  • tests for pre-treatment assessment of people with chronic hepatitis B infection. See Follow up.
  • follow up tests to monitor liver function +/- response to treatment. See Follow up

Tests for diagnosing HBV infection

For assistance with the ordering and interpreting hepatitis B serology please follow the ASHM Decision making tool for hepatitis B (external site).

Patients of unknown HBV status should always have three initial tests performed (HBsAg, Anti-HBs and Anti-HBc) to determine infection status and the need for vaccination. Specify the above tests on the request form rather than ‘hepatitis B serology’. 

People who should be offered testing include:

  • Populations with higher prevalence of chronic hepatitis B:
    • people born in intermediate and high prevalence countries
    • Aboriginal and Torres Strait Islander peoples
    • people who have ever injected drugs
    • men who have sex with men
    • people in custodial settings or who have been incarcerated in a custodial setting
    • people living with hepatitis C
  • Populations with higher risk of onward transmission and/or adverse health outcomes:
    • pregnant people
    • infants and children born to mothers who have chronic or acute HBV
    • patients undergoing chemotherapy or immunosuppressive therapy (risk of reactivation)
    • partners and household contacts of people with acute or chronic HBV
    • people diagnosed with any STI, test for hepatitis B when testing for STIs and at the 3 month follow-up appointment
    • people who have had condomless sex with a new partner
    • people living with HIV
    • people initiating HIV pre-exposure prophylaxis (PrEP).

HBsAg testing is recommended for all pregnant women in the first trimester of each pregnancy to allow appropriate measures to be implemented to prevent newborn infants developing chronic HBV infection.

Window Period

The tests detects antibodies to and antigen of the virus. There is a period after infection, when the test will not detect antibody or antigen because they are yet to be produced or are present at a level that cannot be detected. This is called the window period which may last up to 3 months.

Interpreting serology

HBsAg
anti-HBc
anti-HBs 
positive
positive
negative 
Chronic HBV infection
HBsAg
anti-HBc              
IgM anti-HBc*
anti-HBs
positive
positive
positive
negative
 Acute HBV infection
*(high titre)
HBsAg
anti-HBc
anti-HBs
negative
negative
negative
 Susceptible to infection (vaccination
should be recommended)

 HBsAg
anti-HBc
anti-HBs

negative
positive
positive 
Immune due to resolved infection (record result and consider family screening)
HBsAg
anti-HBc
anti-HBs
negative
negative
positive
Immune due to Hepatitis B vaccination
HBsAg
anti-HBc
anti-HBs
negative
positive
negative
Various possibilities including: distant
resolved infection, recovering from acute HBV, false positive,
 ‘occult’ HBV

Source: ASHM - Decision making in hepatitis B (external site) 

 

Treatment

Treatment of chronic hepatitis B can significantly reduce progressive liver damage and loss of liver function. Treatment is recommended for all HBsAg positive patients with cirrhosis and may be considered in some people with HBeAg positive chronic infection because they are at increased risk of developing complications such as hepatocellular carcinoma or to prevent onward transmission (e.g. health care worker). To assess whether a patient may require treatment follow ASHM Decision Making in Hepatitis B. Treatment generally consists of oral antiviral therapy, e.g. entecavir and tenofovir disoproxil, which needs to be taken on a long-term basis. Less commonly, pegylated interferon may be used.

Health practitioners need to be authorised as a s100 prescriber to prescribe antiviral treatment for hepatitis B. For information and referral see the following list of Hepatitis B s100 community prescribers. Medical and nurse practitioners can enrol in on a national online course to become an s100 prescriber. Patients with chronic HBV should be offered hepatitis A vaccination unless they are known to be already immune because the case fatality rate is high if they develop hepatitis A infection. 

See Follow up section below for details of further investigations required prior to referral of patients with chronic HBV infection.

Education, counselling and prevention

Informing your patient

  • Provide contact details of support services and relevant material.
  • Use a professional interpreter if required. Call Translating and Interpreting Service (TIS) 13 14 50.
  • Fact sheets for patients (Healthy WA)

Reduce transmission

Alcohol - a modifiable risk factor for disease progression

 Status Advise
Early disease with no risk factors for progression, 
consistently normal ALT and normal clinical
examination
Alcohol advice as per general population, NHMRC 
Australian guidelines to reduce health risks from 
drinking alcohol (external site)
Significant fibrosis At most one standard drink/day and no binging
Cirrhosis Aim for total abstinence 

Refer to alcohol and drug services as necessary

Immunisation

People with hepatitis B should be offered HAV vaccination, if not immune. See Guidelines for the Provision of Hepatitis A and B Vaccine to Adults in Western Australia at Risk of Acquiring these Infections by Sexual Transmission (PDF 248KB).

Psychological support and counselling 

For parents and their family/partners, telephone support, education and support groups are available through Hepatitis WA (external site)

Vaccination

Hepatitis B vaccination is part of the WA childhood immunisation schedule.

The National Health and Medical Research Council's (NHMRC) Immunisation Handbook (external site) recommends hepatitis B vaccination for adults in the following groups:

  • household or other close (household like) contacts of people with hepatitis B
  • sexual contacts of people with hepatitis B
  • men who have sex with men
  • people who inject drugs
  • sex industry workers
  • individuals with chronic liver disease and/or hepatitis C
  • haemodialysis patients
  • HIV positive people and other immunocompromised people
  • inmates of correctional facilities 
  • people at occupational risk e.g. healthcare workers, ambulance personnel, dentists, police, staff of correctional facilities, embalmers, tattooists and body-piercers
  • migrants from hepatitis B endemic countries
  • Aboriginal and Torres Strait Islander people.

Serological testing for evidence of past (or current) hepatitis B infection prior to vaccination may be warranted for certain older children, adolescents and adults, especially those at increased risk of acquiring hepatitis B infection, e.g. people who inject drugs, sex industry workers, immunocompromised people, and those living in communities with higher prevalence of HBV, including migrant communities and Aboriginal and Torres Strait Islander people. Serological testing allows people with HBV infection to be identified which facilitates clinical and public health management to prevent liver damage and onward transmission, respectively.

Standard regimes for vaccination include:

  • 0, 1 and 6 months
  • 0, 1, 2 and 12 months
  • 0, 7, 21 days and 12 months for rapid vaccination of those at highest risk.

Vaccination should be administered into the deltoid muscle.

If doses are missed the course does not need to be restarted, but all doses should be completed. 

Serological testing following hepatitis B vaccination

Post-vaccination testing for Anti-HBs antibody and HBsAg levels is recommended:

  • 3 to 12 months after completing the primary vaccine course in infants born to mothers with chronic hepatitis B infection.
  • 4 to 8 weeks after completion of the primary course for
    • those at significant occupational risk (e.g. healthcare workers whose work involves frequent exposure to human tissue, blood or body fluids)
    • those at risk of severe or complicated HBV disease (e.g. persons who are immunocompromised, and persons with pre-existing liver disease not related to hepatitis B)
    • sexual partners and household, or other close household-like, contacts of persons who are infected with hepatitis B
    • those in whom a poor response to hepatitis B vaccination may occur (e.g. haemodialysis patients, persons with bleeding disorders vaccinated via the SC route).

Post-vaccination serology is NOT recommended for other groups 

A single booster dose (4th dose) of vaccine can be given to confirm non-responder status. Those who are still non-responders after being given the booster/4th dose should have 2 further doses of hepatitis B vaccine at monthly intervals, and be re-tested for anti-HBs levels at least 4 weeks after the last dose.

Work

People with chronic HBV who are health care workers may perform exposure prone procedures (EPPs) if they comply with the Australian National Guidelines for the Management of Healthcare Workers Living with Blood Borne Viruses and Healthcare Workers who Perform Exposure Prone Procedures at Risk of Exposure to Blood Borne Viruses (external site).

Management of partners

On receipt of a notification of a hepatitis B case, the local public health nurse follows up with the reporting doctor and with the case to discuss household and sexual contacts. All household and sexual contacts of a person with chronic hepatitis B should be tested for hepatitis B infection. Non-immune household and sexual contacts should be offered free hepatitis B immunisation (and hepatitis B immunoglobulin if significant exposure has occurred). 

For more information see:

Follow up

Chronic hepatitis B 

HBsAg or HBV DNA (PCR) has been detected on two occasions at least 6 months apart. For assessment, management and ongoing monitoring guidance refer to the ASHM Decision making tool for hepatitis B.

Symptom Management 

  • Control of fatigue: advise planning rest periods during the day and the addition of light to moderate exercise into their routines to reduce fatigue.
  • Psychological support and counselling available through Hepatitis WA (external site)

Referral

Urgent (seen <1 week): If evidence of decompensated liver disease discuss directly with Gastroenterology/General Physician at your local hospital and fax a completed referral directly to the relevant hospital.

Routine

Refer those with:

  • cirrhosis
  • pregnancy
  • raised AFP
  • HBsAg +ve and HBeAg +ve with ALT >2x ULN
  • HBsAg +ve and HBeAg –ve with HBV DNA >2000 IU/ml and raised LFT
  • HBsAg +ve and >40yrs of age with ALT 1-2x ULN
  • High risk of progression and/or are complex.

Information to include with referral:

  • likely date and mode of transmission
  • alcohol consumption
  • other drugs (include injecting drug use)
  • current medications
  • symptoms and signs of hepatitis (e.g. jaundice)
  • investigation results (those in bold in management section).

Note: Patients with HIV co-infection and who are asymptomatic with no signs of chronic liver disease can be managed by Infectious Diseases/Immunology.

Public health issues
  • Notify WA Health of any cases of HBV
  • Contact tracing, testing and vaccination of non-immune sexual, family and household contacts are important to prevent further transmission of HBV. 

Post-exposure prophylaxis 

Percutaneous, ocular or mucous membrane contacts should be given hepatitis B immunoglobulin (HBIG) 400 IU intramuscularly (100IU, if body weight <30kg), as a single dose within 72 hours of exposure.

Individuals sexually exposed should be given HBIG within two weeks of sexual contact. Adults should be given HBIG 400 IU intramuscularly, as a single dose, and vaccination commenced within 7 days of exposure. Hepatitis B vaccination and immunoglobulin can be given at the same time, but at different sites.

Notifications

This is a notifiable infection. Medical practitioners must complete the appropriate notification forms for all patients diagnosed with a notifiable STI/HIV, as soon as possible after confirmed diagnosis.