1 Pox Viruses Hugh B Fackrell FackrelUwindsor ca
1 Pox Viruses Hugh B. Fackrell Fackrel@Uwindsor. ca poxvirus. ppt 12/2/2020
2 Pox Viruses þStructure þClassification þMultiplication þClinical manifestations þEpidemiology þDiagnosis þControl Baron’s Web Site 12/2/2020
3 Structure þBrick shaped complex symmetry ä 240 nm x 300 nm þEnveloped ä antibody neutralization sites þCore contains enzymes for virus uncoating ds. DNA þInner membrane þLateral bodies 12/2/2020
4 Smallpox virus negatively stained Thin section 12/2/2020
5 Pox Viruses Canary pox virus Vaccinia Orf virus 12/2/2020
6 Pox Viruses of Vertebrates þOrthopoxvirus ä smallpox, vaccinia, cowpox, camelpox, mousepox, racoonpox þParapoxvirus ä ORF( contagious pustuular dermatitis, pseudocowpox, bovine papular stomatitis þCapripoxvirus ä sheeppox, goatpox, lumpy skin disease 12/2/2020
7 More Pox Viruses þAvipoxvirus þFowlpox ä canarypox, pigeonpox, fowlpox þLeporipoxvirus ä myxoma, hare fibroma, rabbit fibroma, squirrel fibroma þSuipoxvirus ä Swinepox þUnclassified ä molluscum contagiosum, Tana, Yaba 12/2/2020
8 Multiplication þAttachment ä outer membrane of infectious virion fuses with cell membrane þPenetration ä outer membrane remains with cell membrane þUncoating ä yields infectious intracellular virions ä via cellular enzymes ä exposes core proteins ä DNA dependent RNA polymerase 12/2/2020
9 Clinical manifestations þPrimary localized skin lesion e. g. cowpox ä usually on hand ä occasionally on face or genitals by scratches þGeneralized skin lesions e. g. small pox, molluscum þEncephalitis is rare 12/2/2020
10 Smallpox pustules 12/2/2020
11 Burn infected with vaccinia 12/2/2020
12 Vaccinia complications 12/2/2020
13 Host Defenses þunbroken skin represents primary control þInterferon, nonspecific inflammation þCell mediated immunity þHumoral immunity- outer membrane antigens 12/2/2020
14 Diagnosis þClinical manifestations þHistory of animal contact þElectron microscopy of scab material þCell cultures þChicken embryos 12/2/2020
15 Vaccina Cytopathic Effect Human amnion cell line 12/2/2020
16 Chick Embryo Lesions Infected egg Healthy egg 12/2/2020
17 Vaccinia lesions on Chorio allantoic membrane 12/2/2020
18 Cytopathic Effect of Vaccinia Early Cytopathic effect Hep 2 cell line Late Cytopathic Effect 12/2/2020
19 Smallpox was global 12/2/2020
20 12/2/2020
21 Human Pox Viruses are acquired from animal reservoirs 12/2/2020
22 Control þinfection by zoonotic pox viruses is inevitable ä improved health education ä break link with reservoir þimproved hygiene molluscum contagiosum 12/2/2020
23 12/2/2020
24 Eradication of Smallpox þ easily diagnosed þ effective vaccine- only one serotype þ long incubation period þ low communicability no þ long term immunity animal reservoir þ high morbidity & mortality 12/2/2020
25 Smallpox Eradication (cont) þinfectious only after incubation period þno persistent infection þsubclinical infection rare and not a source of infections þno cultural and social barriers þfeasbility of elmination shown in developing countries þsave surveillence costs in nonendemic developed countries 12/2/2020
26 Punch 1802 smallpox vaccine 12/2/2020
27 DONE!!! 12/2/2020
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