Hepatitis B, viral
Reporting Obligations
Individuals who have or may have HBV infection shall be reported as soon as possible to the local Health Unit.
Epidemiology
Aetiologic Agent
Hepatitis B virus (HBV) is the causative agent. It is a DNA virus, composed of a nucleocapsid core (HBcAg), surrounded by an outer lipoprotein coat containing the surface antigen (HBsAg).
Clinical Presentation
Infants and children with acute HBV infection rarely have symptoms, while 30%–50% of adults are symptomatic. The onset of symptoms is usually insidious with anorexia, fatigue, vague abdominal discomfort, joint pain, fever and jaundice.
Chronic HBV carriers may not display symptoms or experience symptoms associated with cirrhosis and other complications of chronic HBV infection.
Modes of Transmission
Via infectious body fluids including blood, saliva, cerebrospinal fluid (CSF), pleural, peritoneal, semen and vaginal secretions and any other body fluid containing blood. The risk of transfusion-related hepatitis B is extremely low in Canada and the USA because all blood and blood products are tested.
Routes of transmission include:
- percutaneous, principally injection drug users
- sexual: anal, vaginal, oral
- horizontal: household contacts
- vertical: mother to neonate
Incubation Period
Usually 45–180 days, average 60–90 days. It may be as short as 2 weeks to the appearance of HBsAg and rarely as long as 6–9 months.
Period of Communicability
All persons who are HBsAg positive are potentially infectious. Blood is infective many weeks before onset of first symptoms and remains infective through the acute period of disease and chronic period of disease. Cases and carriers positive for HBeAg are known to be highly infectious. Chronic carriers can experience spikes in viremia over time, impacting infectivity.
Risk Factors/Susceptibility
All non-immunized and not adequately immunized people are susceptible; disease presentation is usually milder in children and may be asymptomatic in infants.
Risk factors:
- Injection drug use (IDU)
- Multiple heterosexual sex partners
- Men who have sex with men (MSM)
- Sex with HBV-infected individuals
- Hepatitis B carrier in family
- Blood transfusion; organ transplant
- Co-infection with another STI
- Dialysis recipient
- Invasive surgical/dental/ ocular procedures abroad
- Tattoo/acupuncture/ piercings
- Blood exposure
- Incarceration
Diagnosis and Laboratory Testing
Demonstration in sera of specific antigens and/or antibodies confirms diagnosis. For example: Tests that will be performed for “Acute” Hepatitis B are HBsAg, HBcAb Total (IgG + IgM), HBcIgM — will be performed only if HBcAb (IgG + IgM) Total is reactive. Tests that will be performed for “Chronic” Hepatitis B are HBsAg, HBcAb Total (IgG + IgM).
Treatment and Case Management
Treatment is under the direction of the attending Health Care Provider. Acute cases of Hepatitis B should abstain from sexual contact or practice safer-sex until partners have been appropriately screened and/or immunized. Cases should not donate blood; occupational exposures should be managed according to the individual occupational protocols.
Hepatitis B immunization should be routinely offered to the risk groups (if not previously immunized) listed in the Canadian Immunization Guide, Evergreen edition, Part 4: Hepatitis B, Recommendations for Use.
The patient is eligible for free Hepatitis A vaccine. Household and sexual contacts are eligible for free Hepatitis B vaccine. Vaccine can be ordered through the Health Unit online form found here or by email ([email protected]).
For management of cases refer to the Primary Management of Hepatitis B – Quick Reference Guide (HBV-QR).
Contacts should be assessed and immunized as required. All contacts will be notified by Public Health staff.
Additional Resources
Ontario Hospital Association. “Blood-Borne Diseases Surveillance Protocol for Ontario Hospitals.”
Public Health Agency of Canada. “Primary Care Management of Hepatitis B—Quick Reference (HBV-QR).”
Publicly Funded Immunization Schedule for Ontario, January 2021.
Public Health Agency of Canada. “Canadian Immunization Guide, Hepatitis B Vaccine.”
References
Heymann, D.L. Control of Communicable Disease Manual (19th Ed.). Washington, American Public Health Association, 2008.
Ministry of Health and Long-Term Care, Infectious Diseases Protocol, 2022.
Public Health Agency of Canada, Primary Care Management of Hepatitis B—Quick Reference (HBV-QR).