HEPATITIS B
Causative organism | Hepatitis B virus |
Incubation period | 45-180 days (mean 60 days) |
How far to trace back |
Note: The majority of people with hepatitis B have chronic infection and were infected at birth. Contact tracing needs to be conducted differently than for an acute infection. 6 months prior to onset of acute symptoms. If unknown according to risk history. May include extended family members if vertical transmission to child during pregnancy is likely. Recent diagnosed chronic hepatitis B infection (6 months and possibly parents/siblings). |
Usual testing method | Serology for hepatitis B (HBsAg – Hepatitis B surface antigen, anti-HBs – Hepatitis B surface antibody, anti-HBc – Hepatitis B core antibody). Positive HBsAg indicates current infection. |
Common symptoms |
Jaundice, malaise, abdominal pain, dark urine Clay coloured stool |
Likelihood of transmission per act of condomless intercourse | Unknown |
Likelihood of long-term sexual partner being infected | >20% |
Protective effect of condoms | High |
Transmission by oral sex | Low |
Duration of potential infectivity |
In acute hepatitis B infection, two weeks before onset of symptoms and until the patient becomes surface antigen negative. More than 95% of adults who are immune-competent, infected with hepatitis B will spontaneously clear the virus. The majority of those who acquire the infection at birth or as a child will have lifelong chronic hepatitis B infection (where the individual has not been previously tested and has a reactive HBsAg 6 months after the baseline test) |
Important sequelae | Severe, acute hepatitis, chronic liver disease, cirrhosis and liver cancer, vertical transmission to child during or after pregnancy |
Direct benefit of detection and treatment of contacts |
Post-exposure prophylaxis for non-immune people exposed to a source that is positive for hepatitis B surface antigen (see below) Detection and management of hepatitis B infection |
Usual management of contacts |
Counselling and testing Post-exposure prophylaxis consists of Hepatitis B Immunoglobulin (HBIG) and vaccination. These need to be provided as soon as possible after exposure. See Australian Immunisation Handbook for details of dosing. |
Contact tracing priority |
People known to be immune to HBV will need no further testing. High for sexual contacts, needle-sharing contacts, a newborn child of an infected birth parent Medium priority for parents and siblings of an adult with chronic hepatitis B infection, close contacts if any risk exposures |
Notification |
Acute viral hepatitis B is notifiable by doctors in all Australian states and territories, and New Zealand Hepatitis B surface antigen-positive results must be notified by laboratories in NSW |
Note: Hepatitis D virus (delta agent) is a deficient virus that is entirely dependent on concurrent hepatitis B infection. Measures to control hepatitis B should control HDV. |
References:
National HBV Testing Police - Conveying Test Results
Hepatitis Australia - Clinical Guidelines
Page last updated April 2021