Epidemiology of hepatitis B in Ireland

Updated August 2014

Hepatitis B virus• 50-100 times more infectious than HIV

• Chronic HBV infection develops in 90% of those infected as infants and 1-10% infected as adults

• Chronic infection can lead to chronic liver disease, cirrhosis, liver failure and liver cancer (usually over 20-30+ years)

• Premature death from liver disease occurs in 15-25% of chronically infected people

• >350 million people chronically infected worldwide

• Vaccine preventable – universal infant vaccination introduced in Ireland in 2008

Worldwide prevalence hepatitis B (Source: CDC Health information for international travel 2014 http://wwwnc.cdc.gov/travel/content/yellowbook/2014/map_3-04.pdf)

Number of notifications of hepatitis B, 1997-2013

Trends in acute hepatitis B notifications by sex and median age, 2004-2013

Trends in chronic hepatitis B notifications by sex and median age, 2004-2013

Mean annual notification rates per 100,000 for acute cases of hepatitis B by age and sex, 2010-2013

Mean annual notification rates per 100,000 for chronic cases of hepatitis B by age and sex, 2010-2013

Hepatitis B notification rates per 100,000 population, by HSE area, 2010-2013

Mean annual hepatitis B notification rates per 100,000 population by HSE area, 2010-2013

20.7

7.1

7.4

7.8

10.2

8.1

3.9

3.8

Most likely risk factor, 2010-2013Acute cases with risk factor data

(90%, n=147)Chronic cases with risk factor data

(50%, n=952)

Region of birth, 2010-2013Acute cases with region of birth

data (92%, n=151)Chronic cases with region of birth

data (46%, n=874)

Summary of acute hepatitis B in Ireland, 2010-2013

• 8% of cases notified 2010-2013 were acute infections

• 164 acute HBV notifications in this time period (annual average: n= 41)

• 31 acute cases of hepatitis B were notified in 2013. This is the lowest number reported since acute/chronic case definitions were introduced in 2004

• 84% of acute cases notified 2010-2013 were male (M:F =5)

• Mean ages at notification: 39 for males, 34 for females

• Median ages at notification: 37 for males, 29 for females

• Where risk factor data available, 74% of cases were sexually acquired•

• Sexual orientation available for 93% of sexually acquired cases: 57% heterosexual, 43% men who have sex with men

• Where country of birth available, 70% of acute cases were born in Ireland

Summary of chronic hepatitis B in Ireland, 2010-2013• 92% of cases notified 2010-2013 were chronically infected

• 1910 chronic HBV notifications in this time period (annual average: n= 478)

• 386 chronic cases of hepatitis B were notified in 2013. This is the lowest number reported since acute/chronic case definitions were introduced in 2004

• 53% of chronic cases notified 2010-2013 were male

• Mean ages at notification: 36 for males, 32 for females

• Median ages at notification: 34 for males, 29 for females

• Data indicate that most chronic cases were born and infected outside of Ireland, mostly in Central & Eastern Europe, Asia and Sub-Saharan Africa

• It is likely that most became infected at birth or in early childhood and have been infected for decades

• Trends in chronic cases are heavily influenced by immigration trends

Hepatitis B prevalence data – IrelandLow risk populations

• General pop (residual sera, 2003)1: HBsAg 0.1%, anti-HBc 1.7%• Oral fluid, postal (1998-9)2: anti-HBs 0.51%• Blood donors (1997-2010)3: HBsAg 0.012%• Antenatal, Rotunda 1998-20004: HBsAg 0.03% Irish, 4.2% non-EU• Antenatal, West of Irl 2004-95: HBsAg 0.21%

1Nardone A et al. Epidemiol Infect 2009;137(7):961-9.2O ’Connell T et al. Epidemiol Infect 2000;125(3):701-4.3Personal communication, Dr Joan O’Riordan, IBTS4Healy CM et al. Ir Med J 2001;94(4):111-2,4.5O ’Connell K et al. Ir Med J 2010;103(3):91-2.

Hepatitis B prevalence data – IrelandHigh risk populations

• Prisoners 19981: anti-HBc 8.7% (18.5% in IDU prisoners)• IDU 2001-22: HBsAg 2%, anti-HBc 17%• Homeless, Dublin 1999-20003: anti-HBc 9%• Asylum seekers, HSE East 1999-20034: HBsAg 5%

1Allwright S et al. BMJ 2000;321(7253):78-82.2Grogan L et al. Ir J Med Sci 2005;174(2):14-20.3Immunisation Guidelines for Ireland 2008.

http://www.immunisation.ie/en/HealthcareProfessionals/ImmunisationGuidelines2008/.4Doyle S. Thesis submitted for MFPHMI, RCPI; 2006.