Transcript Objectives - Viral Hepatitis Prevention Board

Objectives
• To review surveillance systems in Italy for infectious diseases
• To establish an up-to-date epidemiological picture of viral
hepatitis in Italy
• To evaluate current Italian prevention and control measures for
viral hepatitis
• To determine the lessons learnt from the Italian experience successes, failures and obstacles to overcome
• To map out the way forward generally: lessons for Europe.
Background
• Hepatitis B had become a major public health
problem by mid-1970s
• Group of remarkable scientists, doctors and public
health experts tackled the problem; impressive
research output
• 1980s: prevention programmes (e.g. HIV) including
screening, selective immunization, improved living
standards and medical care, changing demography
and behavioural changes
Background (continued)
• Public health held in high regard by public and
politically
• Other viral hepatitides than hepatitis B also a public
health problem, with risks of clinically significant
outbreaks
• High economic costs, including outbreaks of hepatitis
A
• Immunization strategies are cost effective compared
to other health interventions
Organization
• Public health legislation:
– 1978 (first mention of prevention), 1992 and 1999
stressing surveillance and risk assessment
• National health system being revised
– Ministry of Health orchestrating role of local
units/Departments of Prevention
• Public health system “federated”
– economic and organizational autonomy at regional
level, stewardship role, evidence-based prevention
Immunization
• Policy specified in national guidelines
• Region prepares local/regional health plans
accordingly but adapted to local priorities
• 1983: immunization of high risk groups started at
regional level
• Funding from regional sources
• 1991: mandatory screening of pregnant women and
immunization for all infants and 12-year-old
adolescents introduced
• By 2002, more than 10 million children immunized
Surveillance
• Mandatory national level notification of notifiable
diseases
• Voluntary acute viral hepatitis surveillance (SEIEVA),
established 1985
– to identify trends, risk factors, and to identify and
monitor prevention strategies
Epidemiology
• Hepatitis A: from 10/100,000 in 1985 to about 2 in
2001
– risk factors include travel and eating shellfish and
local factors; person-to-person transmission
– immunological status of population
– male/female ratio to be resolved
– still a North/Central - South/Islands divide
– role of vaccine in shortening and ending outbreaks
and preventing secondary cases
Epidemiology: hepatitis E
• Hepatitis E: very low rate of anti-HEV in children but
increasing trend with age - possible cohort effect
– risk factor mainly travel and geographical divide
– only a few cases in Italy
Epidemiology (continued)
• Hepatitis B
– to mid-1970s: unscreened blood, inadequate
sterilization, large family size, high birth rate,
increasing injecting drug use
– 1980s: improved health practices (including
screening), socioeconomic conditions and
demographic patterns, benefits from AIDS
prevention campaigns, selective immunization
– between 1987 and 2001 incidence (/100,000) fell
from 10.4 to 2.0 and from 2.1 to 0.1 in 0-14 yr
age group
Epidemiology (continued)
• Hepatitis B
– in 1991-2001 new cases of infection fell by 40%
compared with 1988-1991, higher in 0-14 and 1524 yr age groups - immunization
– present - historical low, but still some 500,000
HBsAg carriers and new infections in unvaccinated
people - allows some circulation of D virus
– risk factors: sexual intercourse, contact with
HBsAg+ person, injecting drug use, surgical
intervention, blood transfusion
Epidemiology - hepatitis D
• Hepatitis D - marked declines but shift to longstanding advanced disease (acquired in past)
– declines herald the end of the story
Hepatitis B - the future
• Maintain immunization of infants and screening of
pregnant women
• Increase coverage of adults at risk
• Maintain/improve safety of medical procedures
• Improve public and professional awareness
• Surveillance
• Booster doses - are they needed?
Epidemiology (continued)
• Medical research vs public health
– mutant viruses detected in successfully vaccinated
people but no data on person-to-person
transmission and no evidence of a threat to
established vaccination programmes
– greater likelihood of emergence of S-gene mutants
after post-exposure prophylaxis with HBIG and
vaccine
– change in HBeAg and anti-HBe distribution in
chronic HBsAg carriers, with proportional increase
in HB core mutants
Epidemiology (continued)
• Hepatitis C
– picture unclear, but North-South gradient with
overall prevalence of about 3%; rate increases
with age, especially over 50
– screening has secured blood supply
– risk factors: injecting drug use far outweighs
others - principally surgical intervention
(ophthalmological, cardiovascular and
gynaecological) and haemodialysis
Hepatitis C
• Transmission
– no link with mode of delivery or breast-feeding
– concomitant HIV infection increases risk of
neonatal infection from mother
– injecting drug use main risk factor
– alcohol increases risk of hepatocellular
carcinoma/cirrhosis
– in 30-40% of cases source remains unidentified
– molecular epidemiology demonstrates nosocomial
transmission between patients in haemodialysis
centres and other clinical settings - failure of
preventive measures
• epidemiology is changing
Epidemiology and public
health
• Blood supply has never been so safe, but residual risk
defined (HBV, HCV and HIV)
• Sensitive diagnostic tools but very expensive way to
detect 14 instances of HCV in some 15 million blood
donations in 5 European countries
• Ethical and political issues surrounding use of
resources, priority setting, liability, litigation, etc
Lessons learnt - successes
• Clear early identification of a public health burden
and response
• Expertise in Italy: powerful team of scientists,
doctors and public health specialists
• Prevention plan embraced all appropriate public
health measures including then new vaccine;
continued political commitment and support up to
today
Lessons learnt - successes
(continued)
• Prevention plans evidence based
• Case for immunization evident and clear
• National guidelines but flexibility, adaptation and
autonomy at regional level; development of
guidelines recognized to be an iterative process
• Good solid surveillance systems and data
– feedback and involvement important elements
– SEIEVA picks up outbreaks
Lessons learnt - successes
(continued)
• Hepatitis A: decrease with changing epidemiological
pattern in South; risk factors identified; safe vaccine
• Hepatitis B: historical low levels of infection, but
residual reservoir of carriers
• Hepatitis C: low level, changing epidemiology
• Hepatitis D: an ending problem, but changing disease
pattern
• Hepatitis E: very low prevalence
Lessons learnt - successes
(continued)
• Blood supply is secure
Lessons learnt - issues
• Departments of Prevention need clear and agreed
mandates and staff need training
• Changing context in terms of restructuring of national
health service
Lessons learnt - issues
(continued)
• Epidemiology
– risk factors remain especially through failure of
prevention in medical practice and interventions
(e.g. gynaecology/cardiovascular)
– escape mutants exist and circulate - doubtful
public health significance?
– clusters/outbreaks in hospitals may be
underestimated
– privacy laws in other countries may limit tracing in
surveillance
Lessons learnt - issues
(continued)
• Hepatitis A may be underestimated; vaccine may be
considered as a supplement to education and
hygiene
• Hepatitis C - more cost-effective diagnostic tools and
options needed, particularly for non-endemic
situations
• Case definitions need international harmonization
Lessons learnt - issues
(continued)
• Reducing incidence of disease and number of cases
makes it difficult to argue about importance of
disease and enthuse medical students and
professionals about value of immunization and
dangers of disease
• Surveillance systems need to be in place for
immediate interventions (e.g. HAV outbreaks) and
motivation needs to be maintained
Needs identified
• General needs
– to list what is now known and what we need to
know
– to determine relative importance of socioeconomic
factors, improved hygiene, and immunization to
successes in prevention
– to increase coverage even with mandatory
immunization programmes
– to reach members of risk groups who remain
unvaccinated despite free vaccine
Needs identified - continued
– To increase awareness of disease and vaccine to
persuade HBsAg+ mothers to immunize their
children
– to consider universal newborn immunization with
vaccine only as a valuable alternative to universal
infant immunization
– to consider vaccination of blood donors as an
additional means of securing the blood supply
Needs identified - continued
• Epidemiological studies:
– from transmissibility of and susceptibility to escape
mutants of HBV
– factors underlying increase in anti-HBe-positive
chronic hepatitis B
– on transmissibility of and susceptibility to escape
mutants of HBV
– seroprevalence studies of HAV, including
documentation of occupational risks
Needs identified - continued
• For hepatitis A and other food-borne diseases
improve hygiene and food preparation - with
education at personal and societal levels
Conclusion
• Italy is a model for other countries:
– surveillance and data collection
– excellent research and effective use of data
– tightly defined guidelines should be considered by
other European countries
– multidisciplinary expertise and excellent research
– firm policy process
– good programme evaluation