Bunyaviridae Hugh B Fackrell fackreluwindsor ca Filename Bunyavirus
Bunyaviridae Hugh B. Fackrell fackrel@uwindsor. ca Filename: Bunyavirus. ppt 11/2/2020 1
Bunyaviridae Structure l Classification l Multiplication l Clinical manifestations l Epidemiology l Diagnosis l Control l 11/2/2020 Baron’s Web Site 2
Structure l Spherical enveloped particles – 90 -100 nm virus encoded transcriptase l 2 external glycoproteins l multipartite - 3 segments of SS RNA l – antisense - SS RNA C=122 11/2/2020 3
Classification l Genera – Bunyaviruses – Phlebovirus – Nairovirus – Uukuvirus – Hantavirus 11/2/2020 l Immunologically – 35 serogroups – 300 types & subtypes 4
Bunya. Viruses l ARthropod BOorne viruses – Phlebovirus – Nairovirus – Uukuvirus – Hantavirus l ROdent BOrne Viruses – Bunyaviruses 11/2/2020 5
Bunyavirus Replication 11/2/2020 6
Virus RNA transcriptase - ss RNA + m. RNA + ss. RNA Cytoplasm 11/2/2020 Bunyavirus Replication 7
Genetic Reassortment 11/2/2020 8
Serious Bunya Virus Diseases Crimean Congo Hemorrhagic Fever Virus l Rift Valley Fever Virus l La Crosse Virus l Hanta Virus l 11/2/2020 9
Pathogenesis Early – fever & viremia l Late – encephalitis – retinitis – renal involvement l 11/2/2020 10
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Epidemiology Determined by distribution of vector and mammalian host l Humans: accidental dead end hosts l 11/2/2020 12
Diagnosis Presumptive l l febrile illness geographic site of exposure Sean vectors 11/2/2020 Confirmation l l l virus isolation Virus specific Ig. M Rise in antibody titer 13
Control Vectors – arthropods – rodents l Vaccination – Humans: Crimean Congo – Sheep & Cattle : Rift Valley l 11/2/2020 14
Crimean Congo Hemorrhagic Fever Virus Headache l pain in limbs l bleeding from multiple orifices l 11/2/2020 15
Rift Valley Fever Virus Explosive potential l Egypt 1977 l 200, 000 cases l 600 deaths l 11/2/2020 16
La Crosse Virus Fever l convulsions l drowsiness l focal neurological signs l 11/2/2020 17
Hanta Virus l Rodents - transmission to humans via aerosolized excretions and bites. A wide variety of biting insects. 11/2/2020 Hanta virus Web site 18
Hanta Virus l Lipid envelope – susceptible to most disinfectants. – Need to lower p. H < 5 11/2/2020 19
Hanta Virus l tripartite negative-sense RNA – L, >>viral transcriptase – M>> envelope glycoproteins – >. nucleocapsid protein 11/2/2020 20
Hantavirus Pulmonary Syndrome febrile prodrome l followed by – non-cardiogenic pulmonary edema, – hypotension – shock l 11/2/2020 21
Hantavirus l Four corners New Mexico – May 1993 8 deaths l April 5, 1994 68 cases in 17 states – Deermouse in New Mexico - principal reservoir do not cause infections - found in saliva, urine, feces and is shed sporadically -infected animals - blood, organs, saliva feces, urine. 11/2/2020 22
Hanta virus. . . continued – Humans visiting holding areas for animals can become infected in five minutes. – outbreaks of this and associated diseases have been observed in Baltimore, Maryland Soeul, Korea Belgium England 11/2/2020 23
DONE!!! 11/2/2020 24
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