DISEASE NAME:
Hepatitis B
CATEGORY:
Hepatitis
Hepatitis B
Hepatitis B is a viral infection, which causes inflammation of the liver. The most common ways people become infected with hepatitis B are; sexual contact with an infected person, transmission from an infected mother to her baby around the time of birth, and sharing needles and other drug equipment by people who inject or use drugs. Over 90% of adults clear the hepatitis B virus within six months of infection. However, most babies who become infected develop chronic (long-term) infection. This can cause them to develop serious liver disease, such as cirrhosis (scarring of the liver) and liver cancer as adults. Liver damage usually occurs gradually over 20-30 years in people with chronic infection. Most hepatitis B cases notified in Ireland are in people who have immigrated to Ireland from countries with a higher prevalence of hepatitis B. Many were infected at birth or in early childhood and developed chronic infection. Hepatitis B became a notifiable disease in Ireland in 1981.
Hepatitis B is preventable by vaccination. The hepatitis B vaccine was added to the primary immunisation schedule in Ireland in October 2008, for children born from 1st July 2008. Vaccination is also recommended for adults who are in “at risk” groups. For more details on vaccination, please see Immunisation Guidelines for Ireland: Chapter 9.
Number of hepatitis B notifications and notification rate per 100,000 population, 1997- Q1 2024
Last updated: 18 June 2024
Epidemiology of Hepatitis B in Ireland, Trends up to Q1 2024
File Size: 500 KB
Publication Date: 9 July 2024
Hepatitis B vaccination programmes working to eliminate hepatitis B in children
Case definition
Clinical criteria
Not relevant for surveillance purposes
Laboratory criteria
Acute case
At least one of the following three:
- Detection of hepatitis B core IgM (anti-HBc IgM)
- Detection of hepatitis B surface antigen (HBsAg) AND previous negative HBV
markers less than 6 months ago
- Detection of hepatitis B nucleic acid (HBV-DNA) AND previous negative HBV
markers less than 6 months ago
Chronic case
At least one of the following two:
- Detection of HBsAg or HBV-DNA AND no detection of anti-HBc IgM (negative result)
- Detection of HBsAg or HBV-DNA on two occasions that are 6 months apart
Case of unknown status
Any case which cannot be classified according the above description of acute or chronic infection and having positive results of at least one of the following tests:
- Hepatitis B surface antigen (HBsAg)
- Hepatitis B e antigen (HBeAg)
- Hepatitis B nucleic acid (HBV-DNA)
Epidemiological criteria
Not relevant for surveillance purposes
Case classification
A. Possible case
NA
B. Probable case
NA
C. Confirmed case
Any person meeting the laboratory criteria
Note:
The following combination of lab tests shall not be included or notified:
- Resolved hepatitis - Hepatitis B total core antibody (anti-HBc) positive and hepatitis B surface antigen (HBsAg) negative
- Immunity following vaccination - Hepatitis B total core antibody (anti-HBc)
negative and hepatitis B surface antibody (anti-HBs) positive
Elevated levels of IgM in some chronic cases may result in misclassification which could over-estimate the number of acute cases
Current as of: 28 May 2018
Information, Data and Reports for Hepatitis B
Ireland’s specialist service for the surveillance of communicable diseases.