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Parvo Viruses
[email protected]
5/24/2017
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Parvo Viruses
Structure
 Classification
 Multiplication
 Clinical manifestations
 Epidemiology
 Diagnosis
 Control

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Baron’s Web Site
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Parvovirus Structure
Small icosahedral
 non enveloped
 ssDNA + or - strand

Unable to grow Parvovirus in vitro cell culture
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Parvovirinae
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Genus Parvovirus
– Type Species mice minute virus
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Genus Erythrovirus
– Type Species B19 virus Web site
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Genus Dependovirus
– Type Species adeno-associated virus 2
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Classification

Family Parvoviridae
– Subfamily Parvovirinae
– Subfamily Densovirinae
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Densovirinae
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Genus Densovirus
– Type Species Junonia coenia densovirus
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Genus Iteravirus
– Type Species Bombyx mori densovirus
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Genus Contravirus
– Type Species Aedes aegypti densovirus
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Paroviridae Classification old
Parvovirus
– Parvo Virus Like Agent
– Serum Parvo Like Virus
 Dependovirus
– AKA Adeno Associated Virus
 Insect virus
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B19 Genome
Parvovirus B19 Genome
VP1 Coding Region
2444
VP2 Region
3125
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4787
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Clinical manifestations
Mild flu like illness
 Erythema infectosum
 Aplastic Crisis
 Stillbirth Web Site
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Mild flu like illness
Fever
 Headache
 Chills
 Myalgia,
 Malaise
 Sore throat
 hemoglobin conc down
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Erythema infectosum
Fifth Disease
 Rash on face that spreads to exposed
skin eg arms and legs
 Subsides over 2 weeks
 Relapses frequent
 Arthritis of hands, wrists, knees and
ankles
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Web Site
Typical facial exanthem of erythema infectiosum.
Note the sparing of the perioral areas, resulting
in the typical "slapped cheek” appearance.
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Web site
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Lacy, reticular exanthem of the
extremity in a child with
erythema infectiosum.
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Aplastic Crisis
 patients
with Sickle cell anemia ie
chronic hemolytic anemia
 Fever, malaise, myalgia, chills
 Maculopapular rash
– arthritis & joint swelling, itching
 Decreased
RBC formation
– Life threatening
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Web site
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Stillbirth
Parvovirus can cross the placenta
 no congenital abnormalities
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Fifth Disease
Droplets inhaled into
upper respiratory tract
 local replication
 Viremia
 Replication in upper
respiratory tract
 Rash and arthalgia
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Aplastic Crisis
Droplets inhaled into upper
respiratory tract
 virus replicates in bone
marrow
 Reticulocytosis
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Clinical
manifestation
of B19
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Web site
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Web site
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Epidemiology
Most infections before 40 years
 Erythema infectiosum 4-15 years
 65% of adults have antibodies
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Spread by respiratory droplets
 less contagious than measles
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Diagnosis
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Virus detected in serum or throat wash
– Electron microscopy
– EIA, RIA
– DNA hybridization
 Anti
viral IgM in serum
– easier
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Control
No specific control
 patients with clinical erythema
infectiosm not infectious

– already transmitted the virus
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DONE!!!
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