1Disease Classification
Acute or Chronic Hepatitis B
2Causative Agent
Hepatitis B Virus (HAV)
3GTKYCA
Single and Double Strand circular DNA; envelop; spherical virion; four protien coding genes C, P, S, and X
4Epidemiology: Reservoir
Humans, Chimps
5Epidemiology: POE
Compromised Skin or mucosa
6Epidemiology: MOT
Person to person via contaminated body fluids (blood/semen); sharing items contaminated wlood; vertical; viabilityof virus outside host is 7 days
7Incubation Period
8-21 weeks
8Pathogenesis
Virus enters blood stream and travels to liver. Attaches and enters liver cells vis HBsAg. Immune cells attack infected liver cells causing cirrhosis. Integration of viral DNA into the host genome can lead to cancer
9Symptoms- Acute
Fever, Fatigue, LOA, Nausea, vomiting, abdominal pain, dark urine, clay colored bowel movements, joint pain, Jaundice
10How long do symptoms persit?
Up to 6 months
11Latency Stage
months-yrs; asymptomatic
12Complications
Chronic infection (10%); liver cirrhosis, cancer, or failure; Mortality- 15-20% of chronically infected
13Chronic Infection likelihood
90% 0-1 yr; 25-50% 1-5 yr; 6-10% 10+ yr
14Chronic Infection Symptoms
May be symptom free or suffer from malaise, LOA, general fatigue
15Prevention
Vaccination, practice universal precautions, avoid contaminated fluids, hep. B immune globulin can prevent infection if an unvaccinated individual is exposed to contaminated fluids
16Treatment
Acute- rests, fluids, adequate nutrition; Chronic- Antivirals, interferon