Viral Hepatitis вЂњInfectiousвЂќ Viral hepatitis вЂњSerumвЂќ Enterically E transmitted A NANB Parenterally C transmitted B D F, G, ? other Hepatitis A Virus вЂў Naked RNA virus вЂў Related to enteroviruses, formerly known as enterovirus 72, now put in its own family: hepatovirus вЂў One stable serotype only вЂў Difficult to grow in cell culture: primary marmoset cell culture and also in vivo in chimpanzees and marmosets вЂў 4 genotypes exist, but in practice most of them are group 1 пЃ® Incubation period: пЃ® Jaundice by age group: пЃ® Complications: пЃ® Chronic sequelae: Average 30 days Range 15-50 days <6 yrs, <10% 6-14 yrs, 40%-50% >14 yrs, 70%-80% Fulminant hepatitis Cholestatic hepatitis Relapsing hepatitis None Hepatitis A Infection Typical Serological Course Total antiHAV Symptoms Titre ALT Fecal HAV IgM anti-HAV 0 1 2 3 4 5 6 Months after exposure 1 2 2 4 Transmission вЂў Close personal contact (e.g., household contact, sex contact, child day care centers) вЂў Contaminated food, water (e.g., infected food handlers, raw shellfish) вЂў Blood exposure (rare) (e.g., injecting drug use, transfusion) Global Patterns of Hepatitis A Virus Transmission Disease Peak Age Endemicity Rate of Infection High Transmission Patterns Low to High Early childhood Person to person; outbreaks uncommon Moderate High Late childhood/ young adults Person to person; food and waterborne outbreaks Low Low Young adults Very low Adults Person to person; food and waterborne outbreaks Travelers; outbreaks uncommon Very low Diagnosis вЂў Acute infection is diagnosed by the detection of HAV-IgM in serum by EIA. вЂў Past Infection i.e. immunity is determined by the detection of HAV-IgG by EIA. вЂў Cell culture вЂ“ difficult and take up to 4 weeks, not routinely performed вЂў Direct Detection вЂ“ EM, RT-PCR of faeces. Can detect illness earlier than serology but rarely performed. Hepatitis E virus Hepeviridae пѓ Hepevirus Hepatitis E Virus вЂў unenveloped RNA virus, 32-34nm in diameter вЂў +ve stranded RNA genome, 7.6 kb in size. вЂў very labile and sensitive вЂў Can only be cultured recently Hepatitis E - Clinical Features пЃ® Incubation period: пЃ® Case-fatality rate: пЃ® Illness severity: Average 40 days Range 15-60 days Overall, 1%-3% Pregnant women, 15%-25% Increased with age пЃ® Chronic sequelae: None identified Hepatitis E Virus Infection Typical Serologic Course Symptoms IgG anti-HEV ALT Titer IgM anti-HEV Virus in stool 0 1 2 3 4 5 6 7 8 9 Weeks after Exposure 1 0 1 1 1 2 1 3 Hepatitis E Epidemiologic Features пЃ® пЃ® пЃ® пЃ® пЃ® Most outbreaks associated with faecally contaminated drinking water. Several other large epidemics have occurred since in the Indian subcontinent and the USSR, China, Africa and Mexico. In the United States and other nonendemic areas, where outbreaks of hepatitis E have not been documented to occur, a low prevalence of anti-HEV (<2%) has been found in healthy populations. The source of infection for these persons is unknown. Minimal person-to-person transmission. Risk groups for severe course: Pregnancy, DM, obesity, hypertension, ischemic heart disease Genotype 1 (Burma) Genotype 2 (Mexico) -causes epidemies - subtropical regions -Transmitted with contaminated water - Д±n Europe travel associated -Reservoir: Human Genoytpe 3 Genotype 4 (USA-swine) (China) -Sporadic cases - worldwide distributed (except Africa) -Zoonotic -In Europe: autochton -Reservoir: wild boar Epidemiological features of hepatitis E in disease-endemic areas Large outbreaks involving several hundred to several thousand persons in developing countries Sporadic hepatitis cases frequent FecalвЂ“oral transmission (usually through contaminated water) is the predominant route of transmission Insignificant person-to-person transmission Parenteral transmission known but appears to contribute to only a minority of cases вЂў Mother-to-newborn (transplacental) transmission known вЂў вЂў Highest attack rate among young adults aged 15вЂ“40 years, with relative sparing of children вЂў High attack rate and mortality among pregnant women, particularly those in second and third trimesters вЂў Low overall case fatality rate вЂў Chronic infection ? Immunosuppression? вЂў Superinfection can occur among persons with chronic liver disease вЂў Overall attack rates during hepatitis E outbreaks have ranged from 1% to 15%. вЂў Diagnosis Detection of anti-HEV IgM and IgG Detection of virus RNA (rarely applied) вЂў Prevention Possibly contaminated drinking water should be avoided as should uncooked food in endemic areas. вЂў Immune globulin is not effective if it comes from donors in western countries. вЂў There is no vaccine.