35 - Rabies virus Shape bullet Shape Genome-ssRNA enveloped virus CPE Negri body Structure of Rabies Virus Structure 抵抵抵抵抵抵 60°C 30min

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Unformatted text preview: Rabies virus Shape: bullet Shape: Genome: -ssRNA enveloped virus CPE: Negri body Structure of Rabies Virus Structure 抵抵抵抵抵抵 60°C 30min 抵 100°C 2min 抵抵抵抵抵抵抵抵抵抵抵 抵抵抵抵抵抵抵抵抵抵抵抵抵抵抵抵抵抵 抵抵抵抵抵抵抵抵 4°C 抵抵抵 1 抵 2 抵抵抵抵抵抵抵抵抵抵抵 Reservoir Reservoir Urban forms: Dogs and cats Sylvatic forms: Bats, foxes, raccoons 抵抵 , wolves, skunks 抵抵 , coyotes 抵抵抵 , mongooses 抵抵 , and biting animals Transmission Transmission By bite or scratch Via saliva Airborne ( bats) BAT BAT armadillo Cat Cat raccoon fox dog Rabies or hydrophobia Fever Dysphagia 抵抵抵抵 Altered mental status Excitement, agitation Paralysis 抵抵 Hydrophobia 抵抵 Hypersalivation 抵抵 Nausea, vomiting 抵 抵 ; 抵抵 Headache malaise 抵抵 Laboratory diagnosis Laboratory Diseased dog: viral antigen and Negri body in brain tissue. Patient: IF assay, PCR. Prevention and treatment Prevention Prevention and treatment Prevention Bite Geographical area, type of animal, severity and site of bite. Animal Live ­ observe in cage: If survives > 8 days, then NOT rabies. Dead ­ brain ­ Negri bodies ­ IFA ­ virus isolation Prevention and treatment Prevention Man Live ­ difficult diagnosis Live ­ difficult diagnosis ­ clinical picture, skin biopsy, corneal impression (antibodies only appear very late) Dead ­ brain sent to Onderstepoort "Negri bodies" in cytoplasm of brain cells; immunofluorescence virus isolation . Human papillomavirus (HPV) (HPV) Biological properties Biological naked dsDNA virus naked with 9 ORF with belongs to belongs Papovaviridae Papovaviridae more than 60 types artificial cultivation unsuccessful. Transmission Transmission contact infection sexual infection congenital infection. Pathogenesis Pathogenesis Host-specific Host-specific Tissue-specific. Disease Disease Cutaneous warts Epidermodysplasia verruciformis Mucosal HPV infections Cervical cancer and other cancers: A significant proportion of cancers is associated with HPV infection: 11% of all cancers in women and 2% of all cancers in men. LIFE CYCLE OF HUMAN PAPILLOMAVIRUS PAPILLOMAVIRUS Laboratory diagnosis Laboratory - Cytology - Histology - Colposcopy in the case of genital HPV infections. - Electron microscopy. Electron - Immunocytochemistry can detect major capsid Immunocytochemistry protein but are generally group specific not type specific specific - DNA detection techniques. This is the only way DNA to type HPVs.PCR to PARVOVIRUSES Human parvovirus B19 DISTINCTIVE PROPERTIES DISTINCTIVE Are small, naked viruses with Are icosahedral nucleocapsids. icosahedral Contain single-stranded DNA Contain and replicate in the nucleus. and Include human parvovirus Include (B19) and adenoassociated virus, a defective virus of the dependovirus genus that requires adenovirus to replicate. requires Human pathogen, B19, has Human tropism for red blood cell progenitors progenitors Human diseases associated with B19 parvovirus Human diseases associated with B Syndrome Host or condition Clinical features Fifth diseases Children Cutaneous rash Adilts Arthralgia­arthrtis Transient aplastic crisis Pure red cell aplasia Hydrops fetails Underlying hemolysis Severe acute anemia Immunodeficiencies Chronic anemia Fetus Fatal anemia EPIDEMIOLOGY EPIDEMIOLOGY These organisms are distributed in nature. Enters the body through: The respiratory tract Blood transfusions Vertically from mother. widely DIAGNOSIS DIAGNOSIS PARVOVIRUS B-19 SEROLOGY Serology Interpretation IgGIgMIgG+ IgM- Current or recent infection Patient should be retested in a few weeks IgG+ IgM+ Direct detection of the viral DNA may be achieved by PCR There has been a past infection Patient probably immune IgG + or – IgM equivocal No past infection Patients susceptible to infection Ongoing or recent infection Fetus may be at risk if patient pregnant IgG- (or equivocal) IgM+ Current infection Patient should be retested in a few weeks Prevention and Treatment Prevention Immunological: no vaccines are available Treatment: Commercial immunoglobulin preparations contain parvo B19 antibodies can successfully eliminate the infection in immunocompromised patients ...
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This note was uploaded on 12/27/2011 for the course STEP 1 taught by Professor Dr.aslam during the Fall '11 term at Montgomery College.

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