Epidemiology of Chronic Hepatitis B virus infection Dr

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

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

Learning Objectives • What is Hepatitis • Mode of transmission • Burden of the disease

n n n Global Impact of HBV A Significant Cause of Worldwide Morbidity and Mortality >2 billion have been infected 1 4 million acute cases per year 1 1 million deaths per year 1 350 million chronic carriers 1 n 25% of carriers die from severe liver disease like chronic active hepatitis, cirrhosis, or liver cancer 1 2 nd most important carcinogen behind tobacco 3 Causes 60%– 80% of all primary liver cancer 1 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. ” 8 th ed. 4. CDC. MMWR. 2001; 50:

Breakdown of HBV-induced Deaths per Year (Total = 2 m) Manifestation No. of Deaths Liver Cirrhosis 700, 000 Acute Hepatitis 500, 000 Chronic Hepatitis 400, 000 Hepatocellular Ca 300, 000 Fulminant Hepatitis 100, 000

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 • HIV – human immunodeficiency virus WHO, 2008

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

HBV in Nigeria Researcher Place, year Population studied n Prevalence Anti-HBc of HBs. Ag Mutimer, Benin, 1994 general popn 15% Gasau Maiduguri, 1991 Gen. popn HCC cases 36% 80% Olubuyide Ibadan, 1997 general popn 25% Otu 1987, Calabar HCC cases 200 80% Ndububa, Ile-Ife, 2001 HCC cases 154 61% 80% 84. 4%

SOUTH WEST • Ile-Ife: HBs. Ag 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: HBs. Ag Prevalence – Healthy controls (24%) Lagos: – Hospital Staff (surgeons 25. 7%, – Hospital administrators 15%) (Belo, 2000)

SOUTH EAST • • • Nsukka: HBs. Ag rate 9. 1%, > 1 HBV marker (66%) > 1 HBV marker by age 40 (87%) Rural population affected more than urban (Amazigo & Chime, 1990)

SOUTH-SOUTH HBs. Ag 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)

NORTH CENTRAL • Ilorin: HBs. Ag 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%) HBs. Ag in HCC, 49% (Fakunle et al, 1977 & 1981)

NORTH EAST • Maiduguri: HBs. Ag in – blood donors, 14. 9% (Chikwem et al, 1999) – Anti-HBc in healthy controls, 84. 4% (Gashau & Mohammed, 1991) • Jos: HBs. Ag Prevalence – General, 10% Students, 13% Traders, 14% (Sirisena et al, 2002) - -

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

Who is number 8? Average prevalence rate about 13. 7% 19 million Nigerians with current infections population 150, 000

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

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 10 yrs) • 70 -90% of these children will become chronic carriers

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

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) Hepatitis B Hepatitis C HIV Total Annual incidence 8. 2 of infection from unsafe injections(x 10 6) 2. 3 0. 1 10. 6 Future deaths (x 10 6) 1. 0 0. 2 0. 1 1. 3 No of years of life lost(x 10 6) 19. 7 3. 6 2. 7 26. 0 Direct medical costs of disease (x 10 6) USD 327 59 149 535

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

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%

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

Prevalence of HBV Serologic Markers in Population Groups Who Should Be Tested. Prevalence of HBV Serologic Markers (%) for HBV Infection Population HBs. Ag Persons born in high endemic areas* 13 Men who have sex with men 6 Injection drug users 7 Dialysis patients 3– 10 HIV infected patients 8– 11 Pregnant females (USA) 0. 4– 1. 5 Family/household and sexual contacts 3– 6 Any Marker 70– 85 35– 80 60– 80 20– 80 89– 90 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 Lok ASF, et al. Hepatology. 2001; 34: 1225. Reprinted with permission of Wiley-Liss, Inc, a subsidiary of parts of the Caribbean (Haiti and the Dominican Republic) John Wiley & Sons, Inc.

In Summary

Do you know your hepatitis B status? B Aware B Tested B treated Thank You