Lecture 3 Viral Hepatitis

Question 1

• What are the different Hep viruses?
• Which ones have a chronic carrier state?
• Which ones are faecal-oral?
• Which ones are parenteral/sexual?

Answer 1

Question 2

• What is the most common form of Hepatits?
• Is it going down in infection? Up?
• What is the biggest concern about those infected with HBV and HCV?

Answer 2

• Hep C is the most common with 30k new cases and 4 million are chronic carriers
  
  • Hep B second most common with 1 M in a chronic state
  • Hep A is third most common
• The numbers of infected people are going down in general but not for HCV
• The problem with chronic carriers is that they’re unaware they have the disease

Question 3

• What is a significant stat about the widespread of HAV?
• What does it mean to be acutely infected?

Answer 3

• About 50% of US population showed antibodies for it pre-vaccine
  
  • High rate of subclinical infections without jaundice
  • No chronic carrier state
• Acute infection:
  
  • accesses new host via fecal oral route and then there is a long incubation of 15-50 days
  • This is when virus is replicating in intestine and the carrier can spread the infection
  • This is prior to clinical symptoms

Question 4

• What is the pre-Icteric phase?
• What is the Icetric phase?

Answer 4

• Both these phases are when clinical symptoms start showing
• PreIcteric phase:
  
  • Begins with fever, lack of energy, anorexia and lack of appetite
  • Leads to vomiting and diarrhoea
• Icteric phase
  
  • Viremia and liver infection leading to necrosis and inflammation
  • Bilirubin excreted in the blood leading to jaundice and melanin in urine to produce dark urine
  • usually lasts 1-2 weeks most patients recover on their own.

Question 5

What are the treatments and prevention of HAV?

Answer 5

Question 6

• What are the major source of infection?
• how many of them are asymptomatic?
• How long is the immunity developed?

Answer 6

• Major source of infection is sexual contact and IV
• 30-50% are asymptomatic
• The antigen appears for 6 months or less followed by the appearance of the Antibody and IgG will last a life time so its life time immunity.

Question 7

• What are the complications of acute hepatitis B infection?

Answer 7

• Fulminant?
  
  • 1-3% of cases Co infection with HEP D virus and has high mortality rate 60-90%
• Chronic: lasts longer than 6 months
  
  • Patient are chronic carriers of HBsAg
  • Chronic active hepitatis CAH
    
    • Coinfection with Hep D virus and developes hepatic necrosis and hepatocellular carcinoma
    • Poor prognosis

Question 8

• How do you prevent Hep B?
• How many vaccines are there?
• What is the recommendation?
• What are the antiviral treatments?
• What is a problem with antivirals?

Answer 8

• 3 forms of vaccines:
  
  • Recombivax HB
  • Engerix-B
  • Twinrix
• Recommended to take 3 doses and 98% protection after complete series
• Antivirals:
  
  • Alpha interferon
  • Lamivuidine (Nucleotide analogue)
  • Baraculude

Question 9

• How is HCV contracted?
• What are the 5 key points in lecture?

Answer 9

How is HCV contracted?

• 40-50% are intravenous drug use
  
  • Transfusions
• Renalhemodyalisis
• tattooing and high risk behavior

Key points:

• The high rate of subclinical cases 60-70%
• Causes of chronic liver disease and cancer
• Chronic carrier state 80%
• The onset of illness is insidious

Question 10

• How do you diagnose HepC?
• What is the traditional antiviral therapy?
• Is there a vaccine?

Answer 10

• Diagnosis:
  
  • Abnormal liver function
  • Elvated HCV antibodies (By Elisa)
  • VIral RNA in PCR serum
• Traditional treatment?
  
  • Alpha interferon
  • Pegylated Alpha interferon
  • Ribavirin and Pgalpha-Inf combination
• No FDA Approved vaccine

Question 11

• What is the treatment of HCV?

Answer 11

• Very effective new antivirals but very expensive
• Two are simepervir
  
  • Its a protease
• Sofosbuvir
  
  • Polymerase used in combination
  • Used with PEG-INF and RIbavirin will cure up to 90% of genome 1 HCV

Question 12

What is HDV?

Answer 12

Question 13

What are the clinical aspects of HDV?

Answer 13

• HDV only present in HBsAg Carriers that may progress to liver cirrhosis or hepatocellular carcinoma (30% mortality)
• Hemophilliacas and IV drug users are at risk

USe Anti HDV antibodies to detect

Question 14

What is HEV?

Answer 14

• Wide spread infection cause Acute hepatitis
• 20 M cases/yr 10-30% mortality
• Rare in US
• No antiviral, no vaccine and no chronic infection