Hepatitis Viruses Important Notes
1. Hepatitis Virus
Read And Learn More: Microbiology Question and Answers
Hepatitis Viruses Long Essays
Question 1. Describe the morphology, spread, prevention, and lab diagnosis of hepatitis B virus
Answer:
Hepatitis-B Virus:
It belongs to the Hepadnaviridae family
Hepatitis-B Morphology:
- It is a complex structure
- Size: 42 nm
- It is a double-shelled particle
Hepatitis-B Structure:
1. Outer Surface Or Envelope
- It contains hepatitis B surface antigen, HBsAg.
- It encloses the inner core
2. Core
- It is an Icosahedral nucleocapsid
- Size: 27 nm
- Contains hepatitis B core antigen, HBcAg
3. Genome
- It is present inside the core
- It is double-stranded DNA and DNA polymerase
- Sera of hepatitis B patients shows three types of particles microscopically.
Antigenic Structure:
Spread:
There are three modes of transmission
Prevention:
1. General preventive measures
- It includes:
- Health education
- Improvement of personal hygiene
- Sterilization measures
- Screening for HBsAg and HBeAg in blood donors
- Avoiding the use of unsterile needles, syringes or other materials
2. Immunization
Hepatitis-B Laboratory Diagnosis:
- Dark urine and yellow coloration of sclera due to jaundice occurs
- Blood shows lymphocytosis
- Prolonged prothrombin time occurs
Question 2. Describe the pathogenicity and laboratory diagnosis of the hepatitis B virus.
Answer:
Pathogenicity of Hepatitis B Virus:
- Pathogenesis of hepatitis appears to be immune-mediated
- HBV causes serum hepatitis
- Infection spreads by
- Blood transfusions
- Serum inoculation
- Sharing of syringes and needles
- Sharing of razors
- Tattooing
- Acupuncture
- Sexual intercourse
- It is more common in drug addicts, prostitutes, and homosexuals
- The virus is highly infectious and even a minute quantity of carrier sera can transmit the infection
Hepatitis B Virus Clinical Features:
- Incubation period- 2-6 months
- Onset – Slow, insidious, severe
- Fever is not prominent
- The course of acute HBV infection is divided into three phases:
- Extrahepatic complications include
- Urticaria
- Arthralgia
- Polyarteritis nodosa
- Glomerulonephritis
- The appearance of circulating immune complexes obtaining viral surface antigen
- Some patients progress to chronic active hepatitis and cirrhosis
Hepatitis Viruses Short Essays
Question 1. Differentiate between hepatitis A and hepatitis B.
Answer:
Hepatitis Viruses Short Question And Answers
Question 1. Danes Particles.
Answer:
- Under the electron microscope, sera from type B hepatitis patients show three types of particles
- The third type of particle is a double-walled spherical structure
- It is 42 nm in diameter
- It is the complete hepatitis B virus
- It was first described by Danes in 1970
- Hence it is known as the Danes particle
Question 2. Quantitative rapid test for hepatitis B antigen
Answer:
The Serological tests used for hepatitis B antigens are
- DNA hybridization
- Polymerase Chain Reaction
- They detect HBV DNA
- They are highly sensitive
- They are quantitative tests