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Parvo Viruses. fackrel@Uwindsor.ca. Parvo Viruses. Structure Classification Multiplication Clinical manifestations Epidemiology Diagnosis Control. Baron’s Web Site. Parvovirus Structure. Small icosahedral non enveloped ssDNA + or - strand.
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Parvo Viruses fackrel@Uwindsor.ca
Parvo Viruses • Structure • Classification • Multiplication • Clinical manifestations • Epidemiology • Diagnosis • Control Baron’s Web Site
Parvovirus Structure • Small icosahedral • non enveloped • ssDNA + or - strand Unable to grow Parvovirus in vitro cell culture
Parvovirinae • Genus Parvovirus • Type Species mice minute virus • Genus Erythrovirus • Type Species B19 virus Web site • Genus Dependovirus • Type Species adeno-associated virus 2
Classification • Family Parvoviridae • Subfamily Parvovirinae • Subfamily Densovirinae
Densovirinae • Genus Densovirus • Type Species Junonia coenia densovirus • Genus Iteravirus • Type Species Bombyx mori densovirus • Genus Contravirus • Type Species Aedes aegypti densovirus
Paroviridae Classification old • Parvovirus • Parvo Virus Like Agent • Serum Parvo Like Virus • Dependovirus • AKA Adeno Associated Virus • Insect virus
B19 Genome Parvovirus B19 Genome VP1 Coding Region 2444 VP2 Region 3125 4787
Clinical manifestations • Mild flu like illness • Erythema infectosum • Aplastic Crisis • Stillbirth Web Site
Mild flu like illness • Fever • Headache • Chills • Myalgia, • Malaise • Sore throat • hemoglobin conc down
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
Web Site Typical facial exanthem of erythema infectiosum. Note the sparing of the perioral areas, resulting in the typical "slapped cheek” appearance.
Lacy, reticular exanthem of the extremity in a child with erythema infectiosum. Web site
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 Web site
Stillbirth • Parvovirus can cross the placenta • no congenital abnormalities
Fifth Disease • Droplets inhaled into upper respiratory tract • local replication • Viremia • Replication in upper respiratory tract • Rash and arthalgia
Aplastic Crisis • Droplets inhaled into upper respiratory tract • virus replicates in bone marrow • Reticulocytosis
Clinical manifestation of B19 Web site
Epidemiology • Most infections before 40 years • Erythema infectiosum 4-15 years • 65% of adults have antibodies
Spread by respiratory droplets • less contagious than measles
Diagnosis • Virus detected in serum or throat wash • Electron microscopy • EIA, RIA • DNA hybridization • Anti viral IgM in serum • easier
Control • No specific control • patients with clinical erythema infectiosm not infectious • already transmitted the virus