Hepatitis Flashcards
systemic illness that primarily affects
the liver, with major cases in children and
adults
Viral hepatitis
Vira hepatitis primarily affects what organ?
Liver
Five key agents of hepatitis
○ hepatitis A virus (HAV
○ hepatitis B virus (HBV)
○ hepatitis C virus (HCV)
○ hepatitis D virus (HDV
○ hepatitis E virus (HEV)
causing infectious hepatitis
HAV
associated with serum hepatitis
HBV
linked to posttransfusion hepatitis
HCV
requiring HBV co-infection
HDV
responsible for enterically transmitted hepatitis
HEV
HAV family
Picornaviridae
HBV family
Hepadnaviridae
HCV family
Flaviviridae
HDV family
Unclassifies
HEV family
Hepeviridae
HAV GENUS
Hepatovirus
HBV genus
Orthohepadnavirus
HCV genus
Hepacivirus
HDV genus
Deltavirus
HEV genus
Hepevirus
HAV size
27 nm icosahedral
HBV size
42nm, sperical
HCV size
60nm, spherical
HDV size
35nm, spherical
HEV size
30-32 nm, icosahedral
Enveloped hepatitis
HBV
HCV
HDV
DSDNA HEPATITIS
Hbv
Smallest hepatitis
HAV
Acid sensitive hepatits
HBV
HDV
Heat and acid stable hepatitis
HAV
Ether sensitive, acid sensitive
HCV
Acid sensitive
HDV
Fecal oral transmission hepatitis
HAV
HEV
Parenteral treansmission hepatitis
HBV
HCV
HDV
Additional well characterized viruses
that can cause sporadic hepatitis
○ Yellow fever virus
○ Cytomegalovirus
○ Epstein-Barr virus
○ Herpes simplex virus
○ Rubella virus
○ Enteroviruses
Describe HAV
RNA
naked virion
icosahedral shape
HAV ranges in size from 24 to 30 nm
HAV is a member of what family and genus
FAMILY PICORNAVIRIDAE
GENUS HEPATOVIRUS
Infections are spread by the fecal-oral route and are generally due to poor sanitation and hygiene. Food handling transmission is common.
Hepatitis A
Humans can also acquire the infection from contaminated shellfish, including shrimp, oysters, scallops, etc.
HAV
Are vaccines available in HAV?
Yes
HAV incubation period
15-40 days
Liver involvement (jaundice), nausea, anorexia, and malaise.
HAV
Mortality rate is less than 1%.
HAV
HAV is stable to treatment with:
○ 20% ether
○ acid (pH 1.0 for 2 hours)
○ heat (60°C for 1 hour)
HAV Infectivity can be preserved for at leasT
1 month after being dried
HAV stored at
25°C or for years at −20°C
HAV virus is destroyed by:
○ autoclaving (121°C for 20 minutes)
○ boiling in water for 5 minutes
○ dry heat (180°C for 1 hour)
○ ultraviolet irradiation (1 minute at 1.1 watts)
○ treatment with formalin (1:4000 for 3 days at 37°C)
○ treatment with chlorine (10–15 ppm for 30 minutes)
HAV Heating food to
above 85°C (185°F) for 1 minute
disinfecting surfaces with sodium hypochlorite
(1:100 dilution of chlorine bleach)
Diagnosis for HAV
● HAV initially was identified in stool and liver preparations by using immune electron microscopy as the detection system
● Clinical symptoms and liver enzymes, particularly alanine aminotransferase, are elevated.
● Serology (ex. PCR)
● Primate cell lines
will support growth of HAV, although fresh isolates of virus are difficult to adapt and grow.
Various primate cell lines
made it possible to detect HAV in stools and other samples and to measure specific antibodies in serum.
Sensitive serologic assays and
polymerase chain reaction (PCR)
HAV SEROLOGIC INDICATORS
● Anti-HAV IgM is positive in acute infections.
● Anti-HAV IgG (positive) and anti-HAV IgM (negative) indicate a past HAV infection.
● General serology testing also includes ruling out hepatitis B virus.
positive in acute infections
Anti-HAV IgM
indicate a past HAV infection.
Anti-HAV IgG (positive) and anti-HAV IgM (negative)
includes ruling out hepatitis B virus.
General serology testing
HAV PREVENTION AND CONTROL
Formalin-inactivated HAV vaccines
Immune (γ) globulin (IG)
made from cell culture adapted virus
Formalin-inactivated HAV vaccines
safe, effective, and recommended for use in persons more than 1 year of age.
Formalin-inactivated HAV vaccines
prepared from large pools of normal adult plasma
Immune (γ) globulin (IG)
confers passive protection in about 90% of those exposed when given within 1–2 weeks after exposure to hepatitis A.
Immune (γ) globulin (IG)
HBV characteristics
DsDNA
Envelope
42nm to 47nm referred to as Dane particle
The virus is unusual in that an RNA intermediate is required for replication of the genome. The virus needs a viral-encoded reverse transcriptase for replication.
hbv
HBV FAMILY
Hepadnaviridae
HBV transmission
Infections are spread by contaminated body fluids, including blood. HBV can be sexually transmitted
Infections are associated with contaminated blood products, needle sticks, tattoos, body piercing, intravenous drug abuse, and renal dialysis.
HBV
Are there any vaccines for HBV
Yes
HBV incubation
50-180
HBV Acute infections produce symptoms
resembling WHAT HEPATITIS
HAV
HBV Chronic infections are common and can
result in
cirrhosis and hepatocellular carcinoma.
Diagnosis HBV
a. Clinical symptoms and elevated liver
enzymes
b. Serology
HBV The most useful detection methods are IN SEROLOGY
ELISA FOR HBV antigen
PCR for viral dna and antibodies
is the first marker to be positive, but it will become negative as the patient recovers
HBsAg
In chronic infections, it will remain positive.
HBsAg
Presence of this marker indicates that the patient is infectious.
HBsAg
Antibody to HBsAg indicates recovery or immunity after HBV vaccination.
anti-HBs
is generally present for life.
anti-HBs
indicates recent acute infection.
anti-HBc IgM
As anti-HBs are forming, the level of HBsAg is decreasing. During this transition, there is a point when both markers are undetectable. At this time, the only indicator of HBV infection is
anti-HBc IgM
called the “core window”
anti-HBc IgM
positive in acute infection stages.
Total antibody to HBcAg
also indicates current or past infections but does not indicate recovery or immunity
Total antibody to HBcAg
is positive in acute and chronic stages of
infection. Presence of this marker also indicates
that the patient is infectious.
HBeAg
associated with a good prognosis.
Anti-HBe
Prevention of HBV
Preexposure prophylaxis
HCV characteristics
RNA
LIPID ENVELOPE
HCV family and genus
Flaviviridae
Genus Hepacivirus
most common cause of non-A, non-B (NANB) hepatitis. It is common worldwide
HCV
Transmission HCV
Spread through contaminated blood products, organ transplants, renal dialysis, and intravenous drug abuse
HCV vaccine
No vaccine
appears to be a major contributor to chronic liver disease and cirrhosis in the United States.
HCV
HCV incubation
2-25 weeks
Acute HCV is often symptoms?
Mild and asymtomatic
more likely to cause chronic hepatitis, resulting in cirrhosis, than HBV.
HCV
one of the most asymptomatic common reasons for liver transplant in the U.S.
HCV
HCV diagnosis
● Elevated liver enzymes
● Serologic indicators (anti-HCV and HCV antigen) and nucleic acid amplification
(NAAT)
● The virus has not been grown in cell
cultures
detect antibodies to HCV but it does not
distinguish among acute or chronic
result infections.
Enzyme immunoassays
detects the presence of circulating HCV RNA and useful for monitoring patients using antiviral therapy.
RT-PCR
Prevention HCV
● screening and testing blood, plasma, organ, tissue, and semen donors; virus inactivation of plasma-derived products
● counseling of persons with high-risk drug or sexual practices
● implementation of infection control practices in health care and other settings
● professional and public education
HDV characteristics
RNA
NAKED
35 to 37 nm
Also called as delta virus
HDV
HDV requires but does not encode for ________
HBsAg
only replicates in cells also infected with HBV
HDV
occurs when an individual acquires both HBV at the same time.
Coinfection
is when a patient with an HBV infection is exposed to HDV.
superinfection
More severe
Coinfection or superinfection
Superinfection
HDV May be associated with fulminant hepatitis
Superinfection
Delta antigen can be found
within certain HB surface antigen particles
defective virus.
Hepatits D
HDV diagnosis
anti-HDV and HDV RNA
Serologic markers for HBV will also be positive; in particular HBsAg
‼️‼️‼️REMINDER‼️‼️‼️‼️
HDV PREVENTION
● Delta hepatitis can be prevented by
vaccinating HBV susceptible persons
with hepatitis B vaccine.
● However, vaccination does not protect
hepatitis B carriers from super infection
by HDV
Anti-HAV IgM positive
Acute infection with HAV
Anti-HAV IgG positive
Past infection with HAV
Anti-HCV positive
Current or past infection with HCV
Anti-HD positive, HBsAg positive
Infection with HDV
Anti-HD positive, anti-HBc IgM positive
Coinfection with HDV and HBV
Anti-HD positive, anti-HBc IgM negative
Superinfection of chronic HBV infection with HDV
Other Human Hepatitis Viruses
HEV
HGV
HEV characteristics
Positive sense
SsRNA
32 to 34 nm
HEV family and genus
Hepeviridae
Genus hepevirus
HEV resembles, but is distinct from,
Calcivirus
HEV transmission
Fecal oral route
HEV Most common cause of hepatitis in some
countries with
Poor sanitation
transmitted enterically and occurs in epidemic form in developing countries, where water or food supplies are sometimes fecally contaminated.
HEV
There is evidence of _______ or ________
infections in rodents, pigs, sheep, and
cattle in the United States
HEV or HEV-like
HEV first documented in samples collected during the
New Delhi outbreak of 1955
29,000 cases of icteric hepatitis occurred after sewage contamination of the city’s drinking
water supply.
HEV
HGV characteristics
RNA
ENVELOPED
Family HGV
Flaviviridae
HGV transmission
transmitted by contact with blood, it can
also be sexually transmitted and
transmitted from mother to children.
Infection seems to be relatively common worldwide, but HGV is believed to be
Non pathogenic
