Hugh B. Fackrell fackrel@uwindsor.ca Filename: Bunyavirus.ppt Bunyaviridae Hugh B. Fackrell fackrel@uwindsor.ca Filename: Bunyavirus.ppt

Bunyaviridae Structure Classification Multiplication Clinical manifestations Epidemiology Diagnosis Control Baron’s Web Site

Structure Spherical enveloped particles virus encoded transcriptase 90-100 nm virus encoded transcriptase 2 external glycoproteins multipartite - 3 segments of SS RNA antisense - SS RNA C=122

Classification Genera Bunyaviruses Phlebovirus Nairovirus Uukuvirus Hantavirus Immunologically 35 serogroups 300 types & subtypes

BunyaViruses Phlebovirus Nairovirus Uukuvirus Hantavirus Bunyaviruses ARthropod BOorne viruses Phlebovirus Nairovirus Uukuvirus Hantavirus ROdent BOrne Viruses Bunyaviruses

Bunyavirus Replication

Bunyavirus Replication - ss RNA Virus RNA transcriptase + mRNA + ssRNA Cytoplasm Bunyavirus Replication

Genetic Reassortment

Serious Bunya Virus Diseases Crimean Congo Hemorrhagic Fever Virus Rift Valley Fever Virus La Crosse Virus Hanta Virus

Pathogenesis Early fever & viremia Late encephalitis retinitis renal involvement

Epidemiology Determined by distribution of vector and mammalian host Humans: accidental dead end hosts

Diagnosis Presumptive Confirmation febrile illness geographic site of exposure Sean vectors Confirmation virus isolation Virus specific IgM Rise in antibody titer

Control Control Vectors arthropods rodents Vaccination Humans: Crimean Congo Sheep & Cattle : Rift Valley

Crimean Congo Hemorrhagic Fever Virus Headache pain in limbs bleeding from multiple orifices

Rift Valley Fever Virus Explosive potential Egypt 1977 200,000 cases 600 deaths

La Crosse Virus Fever convulsions drowsiness focal neurological signs

Hanta Virus Rodents - transmission to humans via aerosolized excretions and bites. A wide variety of biting insects. Hanta virus Web site

Hanta Virus Lipid envelope susceptible to most disinfectants. Need to lower pH < 5

Hanta Virus tripartite negative-sense RNA L,>>viral transcriptase M>> envelope glycoproteins >. nucleocapsid protein

Hantavirus Pulmonary Syndrome febrile prodrome followed by non-cardiogenic pulmonary edema, hypotension shock

Hantavirus Four corners New Mexico April 5, 1994 68 cases in 17 states May 1993 8 deaths 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.

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

DONE!!!