HAV

Question 1

Pathogenesis : spread

Answer 1

1) short incubation hepatitis
2) ( faecal oral) PO–> GI–> vi remora ( allows blood transmission) –> hepatotrophism–> bile–> faeces
3) virus in faeces for 10 days before icterus ~2 months
4) multiply in haptic ute –> slow without cytopathic effect
5) not chronic

Question 2

Pathogenesis: epidemiology

Answer 2

1) 56% of all hepatitis
2) faecal oral
3) source–> food, water, hands
4) more children affected than adults ( dirty hands) p

Question 3

Pathogenesis: resistance

Answer 3

1) very high
2) room temp–> month
3) 100•c –> 5 min
4) ph 1-2 and detergents
5) inhibited by: UV, drying high conc, chlorine solution

Question 4

Disease

Answer 4

IP: 25-30 days 
Prodromal period (1 week): GI &common cold ( flu like) 
Acute hepatitis 
Jaundice( icterus) : 7-11 days 
- icterus in 3:1 adults & 1:12 kids 
- pale face, dark urine ( 2-6 weka) 
- 1 year --> complete recover 
- more children infected, but less severe ( often a symptomatic without jaundice ) 
- death is rare (1%)

Question 5

Diagnostics

Answer 5

1) clinical findings
2) serodiagnosis
3) anti- HAV AB:
- IgM (3-5weeks)
- igG (3 months)
4) ALT aminotransferase of hepatocytes –> higher levels indicate hepatocytes destruction
5) HAV ( AG of capsid) for detection

Question 6

Treatment and immunity

Answer 6

• lifelong
  Prevention:
  -Inactivated HAV vaccine for age 2+
  -passive immunity via gamma globulins from normal adult plasma ( pooled immune serum globulin)
  -works in 90% if given in 1st or 2nd week after exposure
• IgG present in 40% of population
• ethanol fraction inch of 1000 donors blood sample

Question 7

Structure

Answer 7

1) infectious hepatitis
2) diameter : 27nm
3) icosohedral capsid
4) linear ss + RNA
5) no envelope