Question

Compare and contrast Hepatitis B virus, Hepatitis A virus, and Hepatitis C virus with regard to: a) virus characteristics, b) reservoir, c) transmission, d) incubation, e) symptoms, f) complications, and g) immunization.

Compare and contrast chickenpox and shingles, and explain the underlying reasons for their differences in pathogenesis.

Answer 1

	Hepatitis A virus	Hepatitis B virus	Hepatitis C virus
Characteristics	Family: Picornaviridae Icosahedral, non-enveloped, single-stranded Positive-sense RNA	Family: Hepadnaviridae Enveloped, partially double-stranded DNA	Family: Flaviviridae Enveloped, single-stranded positive-sense RNA
Reservoir	Humans	Humans, chimpanzees	Humans
Transmission	Via the fecal-oral route Contaminated drugs and needles, Contaminated food and water Sexual contact	Infectious body fluids Contaminated needles, syringes Sexual contact	Contaminated blood, needles, and syringes Sexual contact
Incubation	Average: 28 to 30 days	Normally:24-180 days Average: 60-90 days	2 weeks to 6 months;
Symptoms	Fever, malaise, anorexia, nausea, abdominal discomfort, dark-colored urine,	Mild fever, anorexia, nausea, fatigue,abdominal discomfort, vomiting, rashes	Anorexia, nausea, fatigue, bleeding easily, dark-colored urine abdominal discomfort, vomiting,
Complications	Liver failure, Pancreatitis, Guillain-Barré syndrome, interstitial nephritis	kidney disease or inflammation of blood vessels Scarring in the liver (cirrhosis), Liver cancer and Liver failure	Scarring in the liver (cirrhosis), Liver cancer, advanced cirrhosis may cause Liver failure
Immunization	Inactivated HAV vaccines	Inactivated vaccine	Not known

Answer 2:

Chickenpox is a viral infection caused by a herpes virus, the varicella-zoster virus. Chickenpox is common in children. It is a contagious disease and spreads through direct contact and coughing and sneezing. Symptoms of Chickenpox include fever, headache, weakness, rash, and blisters. After an encounter with chickenpox, the varicella-zoster virus can remain dormant in the body of the person for many years and can be reactivated as shingles (herpes zoster infection) at any age. Shingles cause pain, rash, and blisters.