Paramyxoviruses
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1 Paramyxoviruses Fackrel@Uwindsor.ca paramyxo.ppt 4/9/2015 2 Paramyxoviruses Structure Classification Multiplication Clinical manifestations Epidemiology Diagnosis Control Baron’s Web Site 4/9/2015 3 Paramyxoviridae Paramyxovirus - parainfluenza, mumps Pneumovirus - respiratory syncytial virus Morbillivirus - measles 4/9/2015 4 Rubella virus is a member of the Togaviridae!!! 4/9/2015 5 Structure: Paramyxoviridae Enveloped 150-300 nm helical, pleomorphic symmetry SS RNA ,antisense monopartite 4/9/2015 6 4/9/2015 7 Viral Proteins RNA-directed RNA polymerase Hemagglutinin parainfluenza measles Neuraminidase parainfluenza 4/9/2015 8 Neuraminidase & hemagglutinin activities are different sites of the same protein 4/9/2015 9 Fusion protein causes syncytia formation 4/9/2015 10 Multiplication Antisense strand -> sense RNA RNA directed RNA polymerase Viral proteins sense RNA template for antisense strands capsid assembly 4/9/2015 11 Paramxyovirus Parainfluenza virus Mumps virus Measles virus 4/9/2015 12 Parainfluenza Viruses 4/9/2015 13 Paraflu:Clinical manifestions mild or severe infections lower and upper respiratory tract particularly in children 4/9/2015 14 Paraflu: Classification types 1,2,3,4 in humans type 4 subtypes A & B 4/9/2015 15 Paraflu: Epidemiology occurs worldwide usually endemic primarily in young children reinfections common 4/9/2015 16 Paraflu: Diagnosis clinical symptoms nonspecific Isolate virus Detect viral antigens Detect rise in specific antibodies 4/9/2015 17 No vaccine is available for Parainfluenza 4/9/2015 18 Mumps virus 4/9/2015 19 Mumps:Clinical manifestions systemic febrile infection children & young adults swelling of salivary glands Parotid gland meningitis common encephalitis can occur orchitis oophoritis in adults 4/9/2015 20 Single mumps serotype shared antigens with paraflu type 1 4/9/2015 21 Mumps:Pathogenesis droplet infection viremia spreads to glands & nervous tissue inflammation & cell death 4/9/2015 22 Mumps:Epidemiology worldwide endemic in urban areas intermittant in rural areas epidemic 2-7 years peak incidence Jan-May 4/9/2015 23 Mumps:Diagnosis TYPICAL clinical diagnosis ATYPICAL isolate virus viral antigen in saliva of CSF Detect specific IgM Detect rising titer of IgG 4/9/2015 24 Mumps: Defenses Interferon humoral immunity cell mediated immunity lifelong protection 4/9/2015 25 Mumps:Control live attentuated vaccine long term protection reinfections can occur 4/9/2015 26 Morbillivirus Measles virus 4/9/2015 27 Measles: Clinical manifestions coryza, conjunctivitis, fever rash maculopapular rash 1-3 days later Complications otitis, pneumonia, encephalitis SSPE (subacute sclerosing panencephalitis)-rare 4/9/2015 28 Measles: Pathogenesis viremia multiples in cells of : lymphatic system respiratory system skin brain 4/9/2015 29 Measles:Host Defenses Interferon Humoral immunity Cell mediated immunity Life long protection 4/9/2015 30 Measles: Epidemiology worldwide endemics & epidemics mainly late winter-early spring 4/9/2015 31 Measles Incidence 4/9/2015 32 Measles: Diagnosis Typical clinical manifestations Atypical Isolate virus Detect specific IgM Detect increase in IgG 4/9/2015 33 Measles: Control Active vaccination Live attentuated virus vaccine long lasting protection Passive immunity measles hyperimmunoglobulin 4/9/2015 34 WHO MeaslesVaccination Strategy "catch-up" everyone aged 1-14 years "keep-up" 90% of children at age 12 months; "follow-up" 3-5 years WHO Report 4/9/2015 35 Pneumovirus Respiratory syncytial virus 4/9/2015 36 RSV:Clinical manifestions upper & lower respiratory tract infection frequent in young children significant in elderly 4/9/2015 37 RSV: Pathogenesis droplets direct contact infects ciliated epithelium of respiratory mucosa localized Antibody Dependent Cytotoxicity 4/9/2015 38 RSV: Host Defenses interferon cell mediated immunity Humoral immunity Secretory immunity ( sIgA) reinfection possible 4/9/2015 39 RSV: Epidemiology worldwide temperate climates epidemic winter and early spring infants & young children 4/9/2015 40 RSV: Diagnosis nonspecific clinical symptoms Isolate virus Detect viral antigen Detect IgM, IgA Detect icrease in IgG 4/9/2015 41 RSV: Control no vaccine ribavrin as aerosol isolate patients in hospitals 4/9/2015
