Rabies virus

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Rabies virus
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• Shape bullet
• Genome -ssRNA
• enveloped virus
• CPE Negri body

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Structure of Rabies Virus
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• ?????,60?C 30min?100?C 2min???????????????????????
  ??????
• ????????4?C???1-2???????????

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Reservoir

• Urban forms Dogs and cats
• Sylvatic forms Bats, foxes, raccoons??, wolves,
  skunks??, coyotes???, mongooses??, and biting
  animals

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Transmission

• By bite or scratch
• Via saliva
• Airborne ( bats)

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BAT
armadillo
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Cat
fox
dog
raccoon
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Rabies or hydrophobia

• Fever
• Dysphagia????
• Altered mental status
• Excitement, agitation
• Paralysis??

• Hydrophobia??
• Hypersalivation??
• Nausea, vomiting????
• Headache
• malaise??

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Laboratory diagnosis

• Diseased dog viral antigen and Negri body in
  brain tissue.
• Patient IF assay, PCR.

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Prevention and treatment
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Prevention and treatment

• Bite Geographical area, type of animal, severity
  and site of bite.
• Animal
• Live - observe in cage If survives gt 8 days,
  then NOT rabies. Dead - brain
• - Negri bodies - IFA - virus isolation

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Prevention and treatment

• Man 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 .

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Human papillomavirus (HPV)
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Biological properties

• naked dsDNA virus with 9 ORF
• belongs to Papovaviridae
• more than 60 types
• artificial cultivation un-successful.

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Transmission

• contact infection
• sexual infection
• congenital infection.

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Pathogenesis

• Host-specific
• Tissue-specific.

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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.

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LIFE CYCLE OF HUMAN PAPILLOMAVIRUS

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Laboratory diagnosis

• - Cytology- Histology- Colposcopy in the case
  of genital HPV infections.- Electron microscopy.
  
• - Immunocytochemistry can detect major capsid
  protein but are generally group specific not type
  specific- DNA detection techniques. This is the
  only way to type HPVs.PCR

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PARVOVIRUSES

• Human parvovirus B19

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DISTINCTIVE PROPERTIES

• Are small, naked viruses with icosahedral
  nucleocapsids.
• Contain single-stranded DNA and replicate in the
  nucleus.
• Include human parvovirus (B19) and
  adenoassociated virus, a defective virus of the
  dependovirus genus that requires adenovirus to
  replicate.
• Human pathogen, B19, has tropism for red blood
  cell progenitors

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EPIDEMIOLOGY

• These organisms are widely distributed in nature.
  
• Enters the body through
• The respiratory tract
• Blood transfusions
• Vertically from mother.

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DIAGNOSIS

• Direct detection of the viral DNA may be achieved
  by PCR

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Prevention and Treatment

• Immunological no vaccines are available
• Treatment Commercial immunoglobulin preparations
  contain parvo B19 antibodies can successfully
  eliminate the infection in immunocompromised
  patients