Hepatitis A #22

medical microbiology disease of the week 10

classification

Hepatitis A — acute

-single stranded ssRNA(+) genome of 7.48 kb.

-3 different genotypes (I, II, & III)

-spherical virion 27-30nm

-non-enveloped

causative agent

Hepatitis A Virus (HAV)

epidemiology

reservoir- humans

portal of entry- digestive tract

transmission- fecal-oral route, contaminated food/water, person to person

(virus is infectious for months in some environments)

incubation

2-7 weeks

pathogenesis

virus infects liver and replicates, eventually released into bile & feces; cell damage and acute inflammation inhibit normal liver function

symptoms

2-3 weeks

dark urine

jaundice

clay colored feces

enlarged liver

mild flulike sypmtoms

complications

relapse

autoimmune hepatitis

loss of bile production

rarely severe liver damage or failure

prevention

vaccination

good hygiene

safe food handling

effective sanitation

treatment

rest, fluids, adequate nutrition