Epidemiology of Chronic Hepatitis B virus infection

1. Epidemiology of Chronic Hepatitis B virus infection Dr OlufunmilayoLesi Consultant Physician and Gastroenterologist College of Medicine, University of Lagos/LUTH July 2011

2. Management of Chronic Hepatitis B virus infection Lesi, Olufunmilayo MBBch, FWACP, FMCP Associate Professor ,Department of Medicine, College of Medicine, University of Lagos Consultant Physician/Gastroenterologist, LUTH MARCH 2011

3. Learning Objectives What is Hepatitis Mode of transmission Burden of the disease

4. Global Impact of HBVA Significant Cause of Worldwide Morbidity and Mortality • >2 billion have been infected1 • 4 million acute cases per year1 • 1 million deaths per year1 • 350 million chronic carriers1 • 25% of carriers die from severe liver disease like chronic active hepatitis, cirrhosis, or liver cancer1 • 2nd most important carcinogen behind tobacco3 • Causes 60%–80% of all primary liver cancer1 1. WHO. Hepatitis B. 2002. 2. Maynard JE, et al. In: Viral Hepatitis and Liver Disease. New York: Alan R. Liss, Inc. 1988. 3. CDC. Epidemiology & Prevention of Vaccine-Preventable Diseases. “The Pink Book.” 8th ed. 4. CDC. MMWR. 2001;50:RR-11.

5. Breakdown of HBV-induced Deaths per Year (Total = 2m)

7. HBV – a highly contagious virus 50–100 times more infectious than HIV Survives outside the body for at least 7 days HBV detectable 30–60 days after infection Virus remains in the body for variable periods of time. Chronic carriers have persistent infection and constitute : enormous reservoir of the virus source of infection for others WHO, 2008 HIV – human immunodeficiency virus

8. HBV in Nigeria • 7.3% -24% have evidence of CURRENT infection • (average 13.7%)-19 million Nigerians • Chronic carriers may have • Decreased life expectancy • Reduced quality of life • High lifetime costs associated with liver disease management and the consequences of HBV infection • Healthcare costs increase with progression of CHB

9. HBV in Nigeria

10. SOUTH WEST • Ile-Ife: HBsAg Prevalence • Blood Donors (7.3%) • General Public (8.8%) (Durosinmi et al, 1991) • CLD Patients (70.8%), (Ojo et al, 1998) • HCC (61%) (Ndububa et al, 2001 & 2005) Ibadan: HBsAg Prevalence • Healthy controls (24%) Lagos: • Hospital Staff (surgeons 25.7%, • Hospital administrators 15%) (Belo, 2000)

11. SOUTH EAST • Nsukka: • HBsAg rate 9.1%, • > 1 HBV marker (66%) • > 1 HBV marker by age 40 (87%)  • Rural population affected more than urban (Amazigo & Chime, 1990)

12. SOUTH-SOUTH HBsAg Prevalence Rate • Benin City, 10.4% (Abiodun et al, 1994 • Malnourished children, 27% • Day Care children, 20% (Akenami et al, 1997) • A & E patients, 29.3% (Halim et al, 2001)

13. NORTH CENTRAL • Ilorin: HBsAg Prevalence Rate - General, 23.4% - Blood donors, 21.7% - ANC patients, 16% • STD patients, 36% (Bada et al, 1996) • Zaria: Under 5 years, 40% • Adults 30 yrs & above, 10% (Anti-HBs, 62.5%) HBsAg in HCC, 49% (Fakunle et al, 1977 & 1981)

14. NORTH EAST • Maiduguri: HBsAg in • blood donors, 14.9% (Chikwem et al, 1999) • Anti-HBc in healthy controls, 84.4% (Gashau & Mohammed, 1991) • Jos: HBsAg Prevalence • General, 10% - Students, 13% - Traders, 14% (Sirisena et al, 2002)

15. Who is number 12? A global disease awareness campaign slogan of the World Hepatitis alliance World Hepatitis Day-July 28

16. Who is number 8? Average prevalence rate about 13.7% 19 million Nigerians with current infections population 150,000,000

17. How do we get hepatitis infection?What social, economic and political factors contribute to driving this epidemic?

18. Infection mostly acquired in childhood in Nigeria! • Unsafe injections in childhood • Child to child transmission • Mother to child • Infants born to hepatitis B positive mothers • Predominant mode of transmission in Nigeria and sub-Saharan Africa (over 70% of children have markers of infection by age 10yrs) • 70-90% of these children will become chronic carriers

19. Unsafe injection Practices • 8-12 billion injections are given in healthcare settings around the world annually • In developing countries over 50% of these are unsafe • Associated with 800,000 HIV infections/y • Associated with 10 million with hepatitis infection • In Nigeria- native/cultural practices and scarification marks, uvulectomy, manicurs, acupuncture etc

23. Global annual incidence, deaths, years of life lost, and costs resulting from unsafe injection practices for hepatitis B, C and HIV infection using best case assumption(WHO 1999)

25. Contact with blood from an infected person • Transfusion of infected blood • Paid/commercial blood donors • IV drug abuse • Contaminated needles/ sharps • Scarification marks • Ear piercing • Circumcision • manicures

26. Sexual contact with an infected person • Predominant route of infection in low prevalence regions such as in Europe and America • Affects mostly adolescents and adults • Infection commonly clears and persists to chronic infections in <10%

27. Modes of Transmission Developed world Developing world (USA, Canada & (SEA, China & sub- western Europe) Saharan Africa)   Sexual contact Vertical & Horizontal & IV drug abuse transmission (80% of cases)

28. Prevalence of HBV Serologic Markers in Population Groups Who Should Be Tested for HBV Infection Prevalence of HBV Serologic Markers (%) Population HBsAg Any Marker Persons born in high endemic areas* 13 70–85 Men who have sex with men 6 35–80 Injection drug users 7 60–80 Dialysis patients 3–10 20–80 HIV infected patients 8–11 89–90 Pregnant females (USA) 0.4–1.5 Family/household and sexual contacts 3–6 30–60 *Africa; Southeast Asia, including China, Korea, Indonesia, and the Philippines; the Middle East, except Israel; South and Western Pacific Islands; the interior Amazon River basin; and certain parts of the Caribbean (Haiti and the Dominican Republic) Lok ASF, et al. Hepatology. 2001;34:1225. Reprinted with permission of Wiley-Liss, Inc, a subsidiary of John Wiley & Sons, Inc.

29. In Summary

30. Do you know your hepatitis B status?B AwareB TestedB treated Thank You