Epidemiology of hepatitis

Presenter : Dr.L.KarthiyayiniModerator: Dr. Abhishek V RautEpidemiology of hepatitisFramework Introduction Hepatitis A,E,B,C,D&GMagnitudeNatural history of the diseaseEpidemiological determinantsMode of transmissionClinical featureSero epidemiologyPrevention & controlHepatitis & HIVGlobal policy report on hepatitis-status of IndiaWHO position of hepatitis vaccine

2Introduction VIRAL HEPATITIS IS A MAJOR PUBLIC HEALTH PROBLEMHepatitis A & E - 0.5-4 % mortalityWorld wide 500 million people have chronic HBV & HCV infectionIn India, 45 million people with HBV 500,000 to 1,000,000 people die every year of HBV-related chronic Hepatitis, cirrhosis or liver cancerOut of nearly 22.6 million children born in India every year, over 9 million will acquire the infection in their lifetime.

3Hepatitis is the inflammation of liver by any causeViral hepatitis is mainly caused by Hepatitis A & E virus - Faeco-oral route - Acute & self limiting Hepatitis B,C & D virus- Parenteral route -Acute & chronicOther viruses- cytomegalovirus, rubella virus, epstein barr virus, yellow fever virus ,herpes zoster virus,etc.Other hepatitis-Alcoholic hepatitis (50% of CLD)(mortality : M-11/100000 & F-6/10000)Auto immune hepatitis, toxic & drug induced hepatitis,

Natural history of acute hepatits

HEPATITIS A

Source:CDCMAGNITUDEGLOBAL: Prevalence of anti-HAV antibodies in general population -15%-100%Worldwide 1.5 million clinical cases yearlyOutbreaks INDIA: seroprevalence of anti-HAV: 54.5%- high socio-economic status85% in low socio-economic status

EPIDEMIOLOGICAL DETERMINANTSAGENT: Picarnovirus family4 human genotypes1 serophytypeHOST:Low endemic areaAdolescents & adults(homosexual, IV drug users)TravellersIntermediate endemic areaLate childhood(faeco oral route)Early adult hoodHigh endemic areaEarly childhood

ENVIRONMENTAL FACTORS:Water borne & food borne epidemicsSanitation & overcrowdingMODE OF TRANSMISSION: Faeco-oral routeParentral route stage of viremiaSexual transmission- homosexual due to ano-oral contact Secondary attack rate among household contacts is 30%INCUBATION PERIOD 28 days

CLINICAL FEATURESSymptoms & signsFever Anorexia Malaise Nausea Abdominal discomfortDark urineJaundiceComplications:Relapsing hepatitisCholestatic hepatitisFulminant hepatitis(0.1%)

SERO EPIDEMIOLOGYIgM- Detectable from 5 days prior to onset of symptoms & declines to undetectable levels within 6 months. IgG-Detect previous infection, persists life long Elevated levels of serum bilirubinElevated hepatic enzymes(AST,ALT)

HAV INFECTION-TYPICAL SEROLOGICAL COURSE

Source: Yim, H. J., et al., (2006). Hepatology.PREVENTION & CONTROLControl of reservoir:Complete bed restDisinfection of faeces & fomites0.5% sodium hypochloriteControl of transmission: promoting personnel & community hygienePurification of community water suppliesProper sanitation & waste disposalDuring epidemics, boiling of water is preferred

Active immunizationInactivated vaccines & live attenuated vaccinesParenterally (IM), 2 dose,6-18 months apart.Combined vaccine(inactivated hepatitis A & recombinant hepatitis B) -0,1,6 mths.Passive immunizationHAV IG Pre & Post exposure prophylaxis -single I.M dose,0.02 ml/kg within 2 weeks

HEPATITIS E

MAGNITUDEGLOBALSEARINDIAMAHARASHTRA

Source:CDCMAGNITUDEGLOBAL:Overall attack rates during hepatitis E outbreaks - 1% to 15%. The rates are highest among young adults (3%-30% Case-fatality rates - 0.5% to 4%During outbreaks mortality rates - 0.070.6%INDIA:Proportion- 10%Seroprevalence of anti-HEV antibodies-upto 50%

EPIDEMIOLOGICAL DETERMINANTSAGENTHepatitis E like virusHOST15-40yrsPregnant mothers-20% fulminant(0.5% mortality)MODE OF TRANSMISSION:Faeco oral routeWater borne diseaseIngestion of raw or uncooked shell fish- sporodic casesVertical transmissionSecondary attack rates 0.7-2.2%INCUBATION PERIOD: 2-9 weeks

CLINICAL FEATURESSymptomsAbdominal painNauseaVomitingAnorexiaSigns JaundiceHepatomegaly

SERO EPIDEMIOLOGYElevated antibody levels-RT-PCR

SymptomsALTIgG anti-HEVIgM anti-HEVVirus in stool012345678910111213Hepatitis E Virus InfectionTypical Serologic CourseTiterWeeks after ExposureSource: Yim, H. J., et al., (2006). Hepatology.282828PREVENTION & CONTROLGood personnel hygieneHigh quality standards of public water supplyProper disposal of sanitary wasteVaccines undergoing clinical trails

HEPATITIS B

Source:CDCMAGNITUDEGLOBAL:2million 240 billion carriers60-80% of all primary liver cancerHigh endemicity, intermediate endemicity & low endemicityINDIA:Point prevalence of hepatitis B is 2.1% chronic carrier rate 1.7%HCC 1.6% of all cancersHigh carrier state among health workers 11% & in general population 5%

High (>8%): 45% of global populationlifetime risk of infection >60%early childhood infections commonIntermediate (2%-7%): 43% of global populationlifetime risk of infection 20%-60%infections occur in all age groupsLow ( 95% (infants, children & young adults)More than 40yrs protection 30%Chronic hepatitis-8-21%Cirrhosis-15-19%:

EPIDEMIOLOGICAL DETERMINANTSAGENT:RNA virusSatellite virus or sub viral agentHOST: high risk groupMODE OF TRANSMISSION: Parenteral route Perinatal route Sexual transmissionINCUBATION PERIOD: 30-180 days

CLINICAL FEATURESCo-infection: Simultaneous infcetion Acute form of HBV & HDVSelf limitingChronic form -< 5%Super infection:HDV infection of chronically infected HBVSevere acute hepatitis chronic hepatitis (80%)Associated fulminant acute hepatitis, severe chronic active hepatitis-cirrhosis

anti-HBsSymptomsALT ElevatedTotal anti-HDVIgM anti-HDVHDV RNAHBsAgHBV - HDV CoinfectionTypical Serologic CourseTime after ExposureTitre222222

JaundiceSymptomsALTTotal anti-HDVIgM anti-HDVHDV RNAHBsAgHBV - HDV SuperinfectionTypical Serologic CourseTime after ExposureTitre

232323Diagnosis:RT-PCR EIATreatment:A-interferon (9million units, TDS weekly for 12 months or 5 million units daily for 12 months)Prevention & control:Pre & post exposure prophylaxis of HBVHealth education to reduce risk behaviour

HEPATITIS G

1995-Flavivirus familyGBV-A,GBV-B,GBV-CGBV-C affects man.Transmission : blood transfusionSexual contactVertical transmissionIntravenous drug usersGlobally 1-3% in volunteer blood donorsIncubation period-30-120 daysHGV co-infection is observed in 6% of chronic HBV infections & in 10% of chronic HCV infections.

HEPATITIS & HIVAbout one-third of HIV-infected persons are coinfected with hepatitis B or hepatitis C, which can cause long-term (chronic) illness and death. 10% of 40 million people of HIV are co-infected with HBVViral hepatitis progresses faster among persons with HIV infected personsHIV/HBV & HIV/HCV coinfection -leading cause of non-AIDS-related deaths

HEPATITIS & HIVCoinfection with hepatitis -complicate the management of HIV infection. To prevent coinfection with hepatitis B, universal hepatitis B vaccination of susceptible patients with HIV infection or AIDS & high risk groups is recommendedAll persons living with HIV should be tested for hepatitis B and hepatitis CCoinfected persons should be counseled about drug interacions and side efects of hepatitis and HIV treatments.

Global policy 2010 World Health Assembly to generate reliable information as a foundation for building prevention and control measures that match the local epidemiological profile and health system capacities.Survey conducted in mid-2012 by the World Health Organization and the World Hepatitis Alliance. Aim :To gather country-specific baseline data on hepatitis policies in WHO Member States in all six regions.offers insight into conditions in specific countriesGaps that need to be filled are identified

Issues addressedNational coordinationAwareness raising & partnershipsEvidence based policy & data for actionPrevention of transmissionScreening care & treatment

National coordination

Written national strategy plan-raising awareness, surveillance, vaccination, prevention of transmission via injecting drug use, in health-care settings, in general, and treatment and care.There is a designated governmental department :For coordinating and/or carrying out viral hepatitis related activitiesFour staff membersNot known how many people work full-time in all government agencies/bodies.The government has a viral hepatitis prevention and control programme: activities targeting health-care workers, including health-care waste handlersAwareness raising & partnerships

Not known whether the government held events for World Hepatitis Day 2012Funding-other viral hepatitis public awareness campaigns since January 2011.The government does not collaborate with in-country civil society groups to develop and implement its viral hepatitis prevention and control programmeEvidence based policy & data for action

There is no routine surveillance for viral hepatitis.There are standard case definitions for hepatitis. Hepatitis deaths are not reported to a central registry. No classification:undifferentiated or unclassified hepatitisHCC & HIV/hepatitis coinfection cases are registeredThe government does not publish hepatitis disease reports.Hepatitis outbreaks are reported & investigatedThere is inadequate laboratory capacity nationally to support investigation of viral hepatitis outbreaksThere is no national public health research agendaViral hepatitis serosurveys are not conducted regularlyPrevention of transmission

There is a national policy that specifically targets mother-to-child transmission of hepatitis B There is no national policy on hepatitis A vaccination.The government has not established the goal of eliminating hepatitis B.It is not known what percentage of newborn infants nationally received the 1st dose of hepatitis B vaccine within 24 hours of birth or what percentage of 1yr received 3 doses of hepatitis B vaccine. It is not known whether there is a specific national strategy for preventing hepatitis in health-care settings. Health-care workers are vaccinated against hepatitis B prior to starting workContd..There is a national policy on injection safety in health-care settings-auto-disable syringesSingle-use or auto-disable syringes, needles and cannulas are always available in all health-care facilities.Official government estimates of the number and percentage of unnecessary injections administered annually in health-care settings are not known.There is a national infection control policy for blood banks. All donated blood products nationwide are screenedIt is not known whether there is a national policy relating to the prevention of viral hepatitis among people who inject drugs.The government has guidelines that address how hepatitis A and hepatitis E can be prevented through food and water safety.

Screening care & treatment

Health professionals obtain the skills and competencies through on the job training.Not known -national clinical guidelines for the managementThe government does not have national policies relating to screening and referral to care for hepatitis B or hepatitis C.People testing are register by name & are kept confidentialHepatitis testing are free of charge for all individuals and are compulsory for blood donors.Publicly funded treatment is not available for hepatitisThe following drug for treating hepatitis B & C is on the national essential medicines list: lamivudine & ribavirin respectively The GOI welcomes assistance from WHO in one or more areas of viral hepatitis prevention and controlWho position of hepatitis vaccineAll infants should receive their first dose preferably within 24 hrs Delivery of hepatitis B vaccine within 24 hours of birth should be a performance measure for all immunization programmes. To complete the primary series the birth dose should be followed by 2 doses or, if convenient, by 3 dosesMinimum interval between doses is 4 weeks. There is no evidence to support the need for a booster dose Catch-up vaccination of children should be considered for cohorts with low coverage. The need for catch-up vaccination in older age groups, including adolescents and adults, is determined by the baseline epidemiology of HBV infection in the country. ContdThe importance of vaccinating people with particular risk factors for acquiring HBV infection is emphasized. Eliminating HBV transmission must address- infections acquired perinatally and during early childhood, by teenagers and adults. WHO strongly recommends that all countries develop goals for hepatitis B control Process indicators and the use of outcome measures are critical to verifying achievement goals. Primary tool to measure the impact of immunization-Serological surveys of HBsAg prevalence supplemented by surveillance for acute disease Collection of mortality data

REFERENCE1. Park k., text book of preventive and social medicine, 20th edition; p186 -1892. Mansons text book tropical disease;697-7133. Harrisons principles of internal medicine.17(2);p1945-19604. Berger SA. Infectious Diseases of India, 2012. 503 pages, 67 graphs, 4248 references. Gideon e-books, http://www.gideononline.com/ebooks/country/infectious-diseases-of-india 5. Berger SA. Hepatitis D, E and G: Global Status, 2012. 99 pages, 36 graphs, 1116 references. Gideon e-books, http://www.gideononline.com/ebooks/disease/hepatitis-d-e-and-g-global-status/ 6.heahttp://www.who.int/immunization/topics/hepatitis_b/en/index.htmllth7. Global policy report on the prevention and control of viral hepatitis in WHO Member States.8. http://www.who.int/immunization/documents/positionpapers/en/index.html 9. The Global Prevalence of Hepatitis A Virus Infection and Susceptibility:A Systematic Review10. The Global Prevalence of Hepatitis EVirus Infection and Susceptibility:A Systematic Review

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