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In the name of GodIn the name of God
EpidemioEpidemiologylogy
Acute Acute
viral hepatitis in Iranviral hepatitis in Iran
HAV – Most common cause in pediatric age group . HBV – most common cause in adult . HEV – mainly in endemic areas with poor sanitation . HCV – Rarely present as acute hepatitis . OTHERS – Still unidentified viruses .
Acute Viral Hepatitis In Iran
HAV Prevention HAV Prevention & control& control
sanitation- separate waste from water sourcesanitation- separate waste from water source
and foodsand foods Hand washing, avoidance of contaminated Hand washing, avoidance of contaminated
foodsfoods inactivated virus vaccine is effective (1995)inactivated virus vaccine is effective (1995) human IgG given as passive immunizationhuman IgG given as passive immunization vaccine to travelers or higher risk workers, vaccine to travelers or higher risk workers,
healthcare or sewer workers, food handlers, healthcare or sewer workers, food handlers,
those with chronic liver diseasethose with chronic liver disease
VaccineVaccine
HAV PreventionHAV Prevention
Prior to 1992.Prior to 1992.• Promotion of hygiene to reduce fecal Promotion of hygiene to reduce fecal
oral spread.oral spread.• Short term passive immunization.Short term passive immunization.
Pre exposure for travel to endemic areas.Pre exposure for travel to endemic areas.
1992 – 11992 – 1stst available vaccine in available vaccine in Europe.Europe.• HAVRIX – introduced to the US in 1995.HAVRIX – introduced to the US in 1995.
Routine ImmunizationRoutine Immunization
Goals of HAV immunization areGoals of HAV immunization are• Protect persons from infectionProtect persons from infection• Reduce disease incidence by preventing Reduce disease incidence by preventing
transmissiontransmission• Ultimately eliminate transmissionUltimately eliminate transmission
Children have a high incidence of Children have a high incidence of HAVHAV• This makes them a good target for This makes them a good target for
immunization strategy.immunization strategy.
VaccinationVaccinationSpecial situationsSpecial situations
Patients with HCV & HBV infectionPatients with HCV & HBV infection
Liver transplant patientsLiver transplant patients
Patients with cirrhosisPatients with cirrhosis
EpidemiologyEpidemiologyHBVHBV
Where Is the HBV Where Is the HBV Infection in Asia Pacific?Infection in Asia Pacific?
LongtermLongtermCarriersCarriers Country Country MillionsMillions
ChinaChina 120.0120.0IndiaIndia 48.048.0IndonesiaIndonesia 11.611.6The PhilippinesThe Philippines 7.67.6KoreaKorea 2.52.5JapanJapan 1.31.3Hong KongHong Kong 0.70.7SingaporeSingapore 0.030.03AustraliaAustralia 0.20.2TaiwanTaiwan 3.03.0
Various local sourcesVarious local sources
Chronic hepatitis in IranChronic hepatitis in Iran
Hepatitis B Virus is The Most Common Cause of
Chronic hepatitis (70%) In IRAN yet
Hepatitis B Virus The Most Common Cause of Chronic liver Disease In
IRAN
cirrhosiscirrhosis
Hepatitis B is the cause of Hepatitis B is the cause of more than 80% of cirrhosis in more than 80% of cirrhosis in Iran yetIran yet
Hepatitis B transmissionHepatitis B transmission
portal of entry and transmission- blood portal of entry and transmission- blood bourne bourne
carried to liver by bloodstreamcarried to liver by bloodstream role of immune system in pathogenesis is role of immune system in pathogenesis is
importantimportant symptomatic and asymptomatic infectionsymptomatic and asymptomatic infection persistently infected "carrierspersistently infected "carriers”” blood, blood products, semen, shared blood, blood products, semen, shared
needles, unsterile body piercing or tatto needles, unsterile body piercing or tatto equipment, sharing of toothbrushes, razors equipment, sharing of toothbrushes, razors or towels, sexual intercourse, motheror towels, sexual intercourse, mother to childto child
In Iran vertical transmission In Iran vertical transmission ( from mother to child ) seem to ( from mother to child ) seem to be the most common route of be the most common route of
transmission yettransmission yet
HBV prevention and controlHBV prevention and control
highly protective vaccineshighly protective vaccines - HBsAg from serum of carriers (1980’s)- HBsAg from serum of carriers (1980’s) - yeast recombinant HBsAg since 1986- yeast recombinant HBsAg since 1986 - recommended for all, especially healthcare and - recommended for all, especially healthcare and
high riskhigh risk treatment and controltreatment and control - HBIG hepatitis B immune globulin is protective- HBIG hepatitis B immune globulin is protective - education of vaccine and avoiding contact with - education of vaccine and avoiding contact with transmitting agentstransmitting agents - anti-viral : interferon &lamivudin- anti-viral : interferon &lamivudin
Universal Hepatitis B Universal Hepatitis B VaccinationVaccination
The StrategyThe Strategy All infants to be immunised before All infants to be immunised before
the age of 18 months – regardless of the age of 18 months – regardless of countrycountry
In 1998, In 1998, 8080 countries have achieved countries have achieved this goalthis goal
The ExperiencThe Experienc Protection lasts >10 years and booster Protection lasts >10 years and booster
doses doses not required not required
Screening of pregnant women for HBV Screening of pregnant women for HBV markers, ensuring immediate vaccination markers, ensuring immediate vaccination of infants borne to HBsAg+ve mothersof infants borne to HBsAg+ve mothers
Hepatitis B VaccinesHepatitis B Vaccines
Engerix-BEngerix-B®® RecombivaxRecombivax®®
ChildrenChildren 10µg10µg 2.5µg2.5µg
AdultsAdults 20µg20µg 10µg10µg
Each at 0, 1 and 6 monthsEach at 0, 1 and 6 months
Cost of Childhood Cost of Childhood VaccinesVaccines
VaccineVaccine Cost per dose Cost per dose $$
Tetanus Tetanus 0.160.16Measles Measles 0.260.26DTP DTP 0.190.19Yellow fever Yellow fever 0.27-0.310.27-0.31Meningitis Meningitis 0.31-0.410.31-0.41Hepatitis B Hepatitis B 0.65-0.850.65-0.85
Based on WHO/UNICEF data, 1997Based on WHO/UNICEF data, 1997
Vaccination Reduces the Vaccination Reduces the Incidence of Hepatocellular Incidence of Hepatocellular Carcinoma in 6-14 Yr OldsCarcinoma in 6-14 Yr Olds
00
0.50.5
11
1.51.5
22
HCCHCC Brain tumoursBrain tumours
Incidence per 100,000Incidence per 100,000
1981
-82
1981
-82
1982
-83
1982
-83
1983
-84
1983
-84
1984
-85
1984
-85
1985
-86
1985
-86
1986
-87
1986
-87
1987
-88
1987
-88
1988
-89
1988
-89
1989
-90
1989
-90
1990
-91
1990
-91
1991
-92
1991
-92
1992
-93
1992
-93
1993
-94
1993
-94
Chang Chang et al.et al., 1997, 1997
Hepatitis B VaccineHepatitis B Vaccine
Highly effective in preventing Highly effective in preventing infectioninfection
Universal immunizationUniversal immunization• All newbornsAll newborns• All adolescentsAll adolescents• Adults at riskAdults at risk
summerysummery
HBV IN IRAN• Anti HBV-C-Ab 36%(18000000) Age > 25 • HBSAg) 2.5%(1500000)
• HBeAg in HBSAg+ 10%(150000)
•HBV-DNA in HBSAg+ 20%(300000)
EpidemiologyEpidemiologyHCVHCV
Epidemiology HCVEpidemiology HCV
Previously HCV infection was rare in Previously HCV infection was rare in Iran , but recently it s incidence is Iran , but recently it s incidence is increasing gradually especially in IV increasing gradually especially in IV drug usersdrug users
Hcv in IRANHcv in IRAN
intravenous drug abuse and intravenous drug abuse and needle-sharing in the country. needle-sharing in the country. On the other hand, an increase On the other hand, an increase in number of centers providing in number of centers providing hemodialysis and transfusion hemodialysis and transfusion facilities for hemoglobinopathies facilities for hemoglobinopathies generated new sources and generated new sources and susceptible populations in Iran.susceptible populations in Iran.
HCVHCV
in a research , on 5,976 blood in a research , on 5,976 blood donors in Rasht, northern part of donors in Rasht, northern part of Iran, showed that 0.5% of the cases Iran, showed that 0.5% of the cases were positive. Others on North-West were positive. Others on North-West reported a prevalence of 0.97% reported a prevalence of 0.97% positive HCV antibody. In another positive HCV antibody. In another study in Shiraz in southern part of study in Shiraz in southern part of Iran on 7,897 cases, anti-HCV Iran on 7,897 cases, anti-HCV antibodies were found in 0.59%. antibodies were found in 0.59%.
HCV in chronic liver disease HCV in chronic liver disease
In a study that was done in 1999 In a study that was done in 1999 among 162 chronic hepatitis and among 162 chronic hepatitis and cirrhotic patients, HBsAg, anti-HBc cirrhotic patients, HBsAg, anti-HBc Ab, and anti-HCV Ab were positive in Ab, and anti-HCV Ab were positive in 56.2%, 70%, and 40.7% of cases, 56.2%, 70%, and 40.7% of cases, respectively. respectively.
HCV prevention and controlHCV prevention and control
no vaccine availableno vaccine available diagnosis is importantdiagnosis is important transmission means is not always obvioustransmission means is not always obvious milder clinical symptoms than HBVmilder clinical symptoms than HBV no effective treatment except Peg-no effective treatment except Peg-
interferoninterferon major area of study is biology of virusmajor area of study is biology of virus
Prediction of Iranian population older than 25 years old who are infected with viral hepatitis
( HAV , HBV , HCV , and HDV )
Percent of Percent of chronic carrierschronic carriers
Percent of Percent of infected during infected during
lifelife
Type of Type of virusesviruses
0%0% %90%90 AA
%3%3 %40%40 BB
<0.3%<0.3% <<1%1% CC
??10%10% OFOF
HBSAgHBSAg++
20%20% OF HBSAgOF HBSAg++ DD
Virus Virus Seropositivity inSeropositivity in Healthy adult IRANIAN Healthy adult IRANIAN
IgG HAV-Ab Age > 25 year 90% Age > 35 year 99%Anti HBV-C-Ab Age > 25 36%HBSAg 2.5% (1500000)HBeAg in HBSAg positive subject 10% (150000)HBVDNA in HBSAg positive subjects ?!20%(300000)Anti HDV-Ab in HBSAg positive subject 3-10%Anti HCV-Ab 2nd-generation 0.3% HEV Endemic in north & west of IRAN
Au revoirAu revoirA bientotA bientot