Prevention of Hepatitis B: the Foundation of Viral Hepatitis Prevention

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Prevention of Hepatitis B the Foundation of
Viral Hepatitis Prevention

• Harold S. Margolis, M.D.
• Division of Viral Hepatitis
• National Center for Infectious Diseases
• Centers for Disease Control and Prevention
• Atlanta, GA

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Reasons to Combine Viral Hepatitis and HIV/AIDS
Prevention

• Major public health problems
• Routes of transmission overlap
• Effective prevention tools
• immunization, blood screening, universal
  precautions, risk reduction, treatment
• Well established programs for HIV/AIDS
• Lack of integrated prevention activities leads to
  transmission of both diseases, especially viral
  hepatitis

Hepatitis C the tipping point for a new
direction in prevention
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Estimated Number of Persons with Chronic
Bloodborne Virus Infections 1998
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Routes of Transmission andOpportunities for
Prevention of Infection with Hepatitis Viruses
and HIV Overlap Substantially
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Risk Factors for Transmission of Hepatitis
Viruses and HIV
Proportion of Infections ()
Risk Factor
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Prevention and Control of Viral Hepatitis its
becoming more than HBV infection

• HAV, HBV and HCV infection are endemic in most
  parts of the world, including the independent
  states of the former Soviet Union.
• First priority prevention of HBV infection in
  infants and young children infant hepatitis B
  immunization
• Routine disease surveillance will identify
  hepatitis B and hepatitis C in other age groups

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Components of a Hepatitis B Immunization Program

• Immunization
• Infant
• Catch-up for older children ages defined by
  local epidemiology
• Health care workers
• Other high-risk adults groups defined by local
  epidemiology
• Assessment of effectiveness of HepB immunization
• Vaccination coverage (age-specific)
• Population-based serologic assessment
• Acute disease surveillance
• Surveillance for Acute Viral Hepatitis
• All age groups
• Serologic conformation
• Risk factor data - immunization status, source of
  infection

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A Model Hepatitis B Prevention Program

• Immunization
• infant
• catch-up for older children
• health care workers
• other high-risk adults
• Prevent transfusion-transmitted infection - safe
  blood and blood products
• screening of blood donors for HBsAg
• good manufacturing practices for blood products
• pooled products include virus inactivation
• Safe injection practices in all settings
• Infection control practices to prevent
  transmission of bloodborne infections
• Surveillance to assess prevention effectiveness

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Injections among Unvaccinated Children lt 5 years
of age with Acute Hepatitis, Romania1997-1998
Reported Cases HBV HAV Reported Cases HBV HAV
Reported Cases HBV HAV Reported Cases HBV HAV
Cases Controls OR 95CI
Received an injection 16 41 5.1 2.3-11
No injection 23 300 Ref

Population attributable risk among unvaccinated
32
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Prevalence of HCV Infection in Blood Donors
Anti-HCV defined by EIA and supplemental testing
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Proportion of HCV Infections Attributable to
Unsafe InjectionsCase-Control Studies
Population Country
Year Age Attributable Taiwan
(Ho) 1993 Children 84 (Chen) 1990-94
Adults 20 (Sun) 1990 Adults 57 Pakistan
(Luby) 1994-95 All 51 Egypt (El
Sakka) 1996-97 All 88 Calculated from data
provided by authors
Source SIGN, WHO
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Health-Care Procedures and HCV InfectionLow/Moder
ate Endemic Countries
Surgery
Dental Country HCV Pos HCV Neg HCV Pos HCV
Neg Case-Control USA 10 12 24 24
Italy 17 2 22 11 Cross-Sectional
Italy 56 36 91 80 77 57 90 90
Taiwan 13 3 24 28 Pakistan
No data 33 39 Japan 32 10 No
data
Plt.05, independent of other risk factors
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Unsafe Injections and HCV InfectionModerate
Endemic Countries
History Reused Needles/Syringes Country HCV
Pos HCV Neg OR (95 CI) Italy 63 31 3.8
(2.7, 5.3) 89 53 7.0 (4.4,
11.2) 76 72 1.2 (0.6, 2.5) Taiwan 26 8 4
.2 (1.2, 14.5) Pakistan (gt5/yr) 36 6 8.2
(1.9, 41.4)
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Geographic Patterns of Age-Specific Prevalence of
HCV Infection
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Burden of Disease Attributable to Unsafe
Injections, Developing and Transitional Economy
Countries, Preliminary Data
HCV HBV HIV
Total number of infections 4.8 m 64.7 m 5.5 m
Infections attributable to unsafe injection 2.1 m 23.0 m 0.1 m
Attributable fraction 44 36 2
Source Armstrong, Hauri, Hutin
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Posttransfusion Hepatitis in Developing Countries

• Inappropriate use of blood and blood products
  single unit transfusions common
• Lack of organized transfusion services
• Most transfused units not tested for HBV or HCV
• Related donors often used perception that less
  likely to be infected
• Paid donors continue to be used in many countries
  

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Posttransfusion Hepatitis C
All volunteer donors
HBsAg
Donor Screening for HIV Risk Factors
Anti-HIV
ALT/Anti-HBc
Anti-HCV
Improved HCV Tests
Adapted from HJ Alter , et al . Clin Chem 1997
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Injecting Drug Use HBV and HCV Infection

• Highly efficient mode of transmission
• Rapidly acquired after initiation
• Four times more common than HIV
• Prevalence 50-90 after 5 years
• Predominant risk factor in low prevalence
  countries
• Emerging risk factor in medium prevalence
  countries acute hepatitis B and hepatitis C in
  adults are often the best indicator of injection
  drug use problem

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Risk of Bloodborne Virus Infections Injection
Drug UsersBaltimore 19831988
HCV
HBV
Seroprevalence ()
HIV
Duration of Injecting (months)
Garfein RS. Am J Public Health. 199686655.
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Injecting Drug Use and HCV Infection
High/Moderate Endemic Countries

• Minor role in the distant past
• Highest incidence of hepatitis C now seen in
  young adults in some countries (e.g., Italy,
  Japan)
• sentinel event for emergence of injecting drug
  use
• History of injecting drug use becoming more
  common
• 50 of persons with acute hepatitis C (Italy,
  Russia)
• 40 of HCV-positive persons lt40 yrs old vs. 0
  gt40 (Italy)
• 2/3 of HCV-positive commercial blood donors
  (Egypt)

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Relative Importance of Risk Factors for Hepatitis
C and Prevention Strategies by HCV Endemicity

• Risk reduction services
• Testing and counseling

• Safe blood supply
• Safe injections
• Infection control

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Relative Importance of Risk Factors for Hepatitis
B and Prevention Strategies by Endemicity

• Infant, adolescent, adult immunization
• Risk reduction services

• Infant Immunization
• Safe blood supply
• Safe injections
• Infection control