Hep A
charact
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Naked RNA virus
Family: Picornavirus
genus: hepatovirus
Non-enveloped
icosahedral symmetry
One serotype only
incubation
tx
Average 4 weeks Range 3-5 weeks
 Fecal-oral
 Close personal contact, poor hand hygiene : household contact, sex contact (analoral) , child day care centers
 Contaminated food, water : infected food handlers, raw shellfish)
 Blood exposure (rare) : injecting drug use, transfusion) during viraemic period
Clinical features
Clinically milder in young children. Fever, anorexia, nausea, RUQ pain, followed by jaundice.
Dark urine, clay-coloured faeces Majority- full recovery after 8 wks
<6 yrs, <10%
6-14 yrs, 50%
>14 yrs, 80% (more common)
Fulminant hepatitis , Cholestatic hepatitis, Relapsing hepatitis
x
jaundice
cx
Chronic
serology
dx
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protection
px
Liver function tests: raised ALT
Anti HAV-IgM in serum = acute infection
Anti HAV-IgG = past infection = immunity
Direct Detection: EM, RT-PCR of faeces. detect earlier
Life-long
 Improved sanitation,
 strict personal hygiene,
 hand washing
tx
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vaccine
 Inactivated (contains HAV antigen)
 IM injections
 (1 dose + booster at 6-12 mths later)
 Protection at least 10 yrs
Vaccination
Hep A immune globulin
ig
Post-exposure (within 14 days, preferably
within 72hrs): prevent/reduce severity of
disease
o
o
o
Age 40 yrs or older
Where vaccine is contraindicated
In immunosuppressed, chronic liver
disease, children aged < 12 mths.
(For age 12mth-40 yrs: Hep A vaccine is preferred, equivalent efficacy to immune globulin,
long-term protection)
Routine : household and other intimate contacts of confirmed Hep A cases
Selected situations : institutions (e.g., day care centers) ▫ common source exposure & (e.g.,
food prepared by infected food handler)
Hep B
charact
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Hepadnavirus family
Double stranded DNA virus.
The + strand incomplete.
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Replication involves a reverse transcriptase.
Complete Dane particle 42 nm,
containing HBcAg and HBeAg.
incubation
Tx
Average 2.5 mths Range 6 wks – 6 mths
 Parenteral - IVDU, Health Workers are at increased risk.
 Sexual - sex workers and homosexuals are particular at risk.
 Vertical - Perinatal transmission is the main means of transmission in high prevalence
populations.
risk
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Family hx
Alcohol consumption
M>F
age
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jaundice
chronic
Hepatic inflame/ fibrosis
age <5 yrs, <10%
age >5 yrs, 50%
More symptomatic in adults
 age <5 yrs, 30-90% // age >5 yrs, 2-10%
 motality : 25%
 HBsAg seropositive status beyond 6 months.
Subdivided into HBeAg-positive and HBeAg-negative chronic hep- atitis B (CHB).
Serology
tx
HBV infection is considered to have progressed to chronic infection when HBsAg, hepatitis B e
antigen (HBeAg), and high titers of hepatitis B viral DNA are found to persist in the serum > 6
months.
Acute HBV infection is generally considered resolved once an individual has developed anti-HBs
and has cleared HBsAg from their serum
cx
serology
ix
tx
px
Diagnosis : acute/chronic
HBsAg
High serum A/C
Presence : infectious
Antibody against due to normal immune rx
Used in hep b vaccine
Anti-HBs Presence : recover / immunity from hep b virus
After vaccinated
Protective level >10ml
Anti-HBc Presence : onset of symp in acute hep & pesists for life
Non-neutralizing antibodies in A/C
+ve : previous / ongoing infection w hep virus
Anti-HBc +ve : recent infection + hep B virus (<6 mnths)
IgM
+ve : acute infection
HBeAg
+ : active replication of virus > infectiveness
Anti-Hbe Virus x longer replicating
Can still be +ve HBsAg
HBV+ : active replication of virus more acc than HBeAg (mutant)
DNA
Use : monitor response theraphy.
Succesful tx :
EIA
Lav test : ICT / rapid test
 the disappearance of HBV-DNA
Interferons
 seroconversion of HBeAg
Nucleoside : entecavir, tenofovir
 disappearance of HBsAg
 screening of blood donors
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Improved histology
 antenatal screen
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Improved survival
 blood and body fluid precautions
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X IV drug abuse
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vaccination
Safe sexual practice
Hepatitis B vaccination

Contains HBsAg (derived from
yeast cells, recombinant DNA
technology)
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3 doses, im
 3-dose series give long-term
protection, anamnestic
response
 Anti-HBs > 10 mIU/mL
protective
Hep c
charact
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tx
Hepatitis B Immunoglobulin
 Contains anti-HBs
 to protect persons who are exposed to hepatitis B,
given asap
 efficacious within 14 days after exposure
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should also start Hep B vaccine series
 Indicated for persons at risk of contracting hepatitis B:
o NSI / percutaneous exposure in susceptible
individuals (non-immune)
o Newborns of HBV+ mothers (within 12hrs)
o Infants <12 mths with family member HBsAg+
o Unprotected sex with persons with A/Chep B
o New liver transplant to prevent infectio
Flaviviridae family
 positive stranded ss RNA genome
Genus : Hepacivirus
 6 genotypes (type 1 to 6) , 11 subtypes (a-k)
Small, enveloped
( = hep B)
+ transfusion & organ transplant
Hepatitis C is not spread through breast milk, food, water or by casual contact
epid
risk
Southern Italy, Spain, central Europe, Middle East, Egypt
incubation
jaundice
Average 6-8 wks Range 2-26 wks
30-40% (20-30%)
Most cases of acute HCV infection are asymptomatic.
When symptomatic, acute HCV infection tends to follow a mild course.
Common symptom: fatigue
~70%
(about 55-85% of newly infected patients remain viremic > CLD)
Chronic
Chronic C=B
All the manifestations of chronic hepatitis B infection may be seen, albeit with a lower frequency
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chronic persistent hepatitis
chronic active hepatitis ▫ cirrhosis
hepatocellular carcinoma
immunity
serology
No protective antibody response identified
dx
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HCV infection is diagnosed when anti-HCV is present in the serum
Testing for HCV RNA by polymerase chain reaction (PCR) confirms the diagnosis and
documents viremia
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test
Hepatitis C infection is considered to have progressed to chronic infection when HCV RNA
persists in the blood for > 6 mth
HCV antibody
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to diagnose hepatitis C infection.
Not useful in the acute phase
takes ≥4 weeks after infection before antibody appears.
Anti-HCV is non-protective antibody ie does not indicate immunity, and does not guard
against
Not useful to monitor disease progression or response to treatment. future exposures to HCV
Current 3rd generation & 4th generation tests (EIA or CIA) have a specificity and sensitivity of
> 99%.
HCV-RNA
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various molecular techniques are available e.g. PCR
Detection of HCV RNA in blood is the currently accepted “gold standard” for the diagnosis of
active HCV infection
May be used to diagnose HCV infection in the acute phase.
Monitoring of HCV loads during treatment is important for response-guided therapy to
determine futility, treatment protocol, and duration
HCV-antigen
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ix
1. EIA for anti HCV
2. POCT + rapid anti-HCV testing
tx
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screening
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Hep D
chract
Clinical
features
Interferon : 2 types, weekly sc
injections : Interferon alfa-2a // Interferon alfa-2b
Ribavirin : Daily oral dose
New: Directly-Acting Antivirals (DAA) (protease inhibitors) oral, 8-12 weeks
X vaccine
HIV-infected patients suspected of having acute or chronic HCV infection should first be
tested for anti-HCV.
 In addition, HCV RNA testing should be performed in the following groups:
o Those with a positive anti-HCV test;
o Those for whom antiviral treatment is being considered, using a highly-sensitive
quantitative HCV RNA assay; or
o those with unexplained liver disease whose anti-HCV test is negative and who are
immunocompromised or
o suspected of having acute HCV infection.
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tx
Detects HCVcAg, using mAb.
able to detecr early infection (<2w)
used in the same capacity as HCV-RNA tests but is much easier to carry out.
The delta agent is a defective virus which shows similarities with the viroids in plants.
Particle 35 nm in diameter consisting of the delta antigen surrounded by an outer coat of
HBsAg.
The genome of the virus is very small and consists of a single-stranded circular RNA
= HBV / HCV
Sex contact but less than HBV
Coinfection (acute HBV-HDV)
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similar to acute HBV
low risk of chronic infection (90% fully recover)
Superinfection (HBV carrier + acute HDV)
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severe acute disease, often fulminant.
70-80% develop chronic HDV infection.
high risk of severe chronic liver disease.superinfection may give HBsAg+ patients the
appearance of a sudden worsening or
flare of hepatitis B.
HDV superinfection may result in FHF
serology
progressive
chronic HBV and HDV disease tends to progress more rapidly to cirrhosis than chronic HBV
infection alone does. [5]
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Hep E
charact
HBV-HDV Coinfection : Pre or postexposure prophylaxis to prevent HBV
HBV-HDV Superinfection : Education to reduce risk behaviors among persons with chronic
HBV infection
HBV vaccine prevents HDV
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tx
incubation
jaundice
chronic
mortality
Calicivirus-like viruses
 Family Hepeviridae
Non-enveloped RNA virus, 32nm in
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Genus Hepevirus
diameter
 very labile and sensitive
+ve stranded RNA genome
 4 genotypes, 1 serotype
Icosahedral symmetry
• Fecal-oral(usual)through
• Contaminated food and water (common)
• Poorpersonalhygiene
• Directperson-to-personcontact(rare)
Average 40 days Range 15-60 days
Increased with age Frequently subclinical
x
Overall, 1%-3%
Pregnant women, 15%-25%
serology
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No antiviral, symptomatic rx only
No vaccine yet
Avoid drinking water (and beverages with ice) of unknown purity, uncooked shellfish, and
uncooked fruit/vegetables not peeled or prepared by traveler.
Personal hygiene
Hand washing
Acute viral hep
Serology screen for hep viruses ABC :
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IgM antibody to HAV (IgM anti-HAV)
Hepatitis B surface antigen (HBsAg)
IgM antibody to hepatitis B core (IgM anti-HBc)
Antibody to HCV (anti-HCV)
Hepatitis C RNA (HCV-RNA) polymerase chain reaction (PCR)
If any are positive, further serologic testing may be necessary to differentiate acute from past
or chronic infection
If serology suggests hepatitis B, testing for hepatitis B e antigen (HBeAg) and antibody to
hepatitis B e antigen (anti-HBe) is usually done to help determine the prognosis and to guide
antiviral therapy.
If serologically confirmed HBV infection is severe, anti-HDV is measured.
ddx
Systemic dis
immunocom
If the patient has recently traveled to an endemic area, IgM antibody to HEV (IgM anti-HEV)
should be measured if the test is available.
 Liver abscess
 Drug-induced hepatitis
 Autoimmune hepatitis
 Hepatocellular cancer
 Pancreatic cancer
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Epstein-Barr virus (EBV)
Cytomegalovirus (CMV)
Varicella zoster virus (VZV)
Herpes simplex virus (HSV) -part of disseminated infection
Yellow Fever virus - also cause haemorrhagic fever • Dengue virus
-Rubella
• Measles
• Mumps
• Adenovirus