Human herpesviruses

1. Human herpesviruses
1) Herpes Simplex Type 1
The virus usually infects the oral mucosa and is passed through fluid filled lesions.
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Can also cause infections on the skin and in the eyes.
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Diseases or cause; above the waist infections and viral encephalitis in U.S. and focal temporal lesion.
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HSV Type 1 lies latent in the ganglion of the trigeminal nerve.
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Pathogenesis; HSV establishs infection in the mucosal cells.
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2) Herpes Simplex Type 2
The virus usually infects the and anal areas.
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Diseases or cause; below the waist infections; genital infection route.
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HSV Type 2 lies latent in the sacral ganglia.
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Pathogenesis; HSV establishs infection in the mucosal cells.
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Diagnosis for Type 1 and 2
Oral lesions; Clinical
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Encephalitis; PCR on CSF
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Genital infections; Tzank smear
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Varicella zoster virus (VZV)
The virus usually infects tonsils, respiratory mucosa
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Diseases or causes ; chicken pox and shingles, fever pharyngitis, reactivation of latent infection.
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herpes zoster lie latent in neurons.
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Pathogenesis; Varicella zoster virus enters the respiratory tract and replicates in local lymph nodes.
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Diagnosis; Tzanck smear, antigen detection by PCR
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Treatment; Healthy adults with shingles oral acyclovir
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Epstein Barr virus (EBV)
The virus usually infects B cells; epithelial cells.
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Diseases; EBV lies latent in B cells--immortalizes them!
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Pathogenesis; Virus infects nasopharyngeal epithelial cells, salivary and lymphoid tissues.
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Malignancies; Burkitt lymphoma; cancer of the maxilla, mandible, abdomen.
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Diagnosis; heterophile antibody positive (IgM)
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Treatment; symptomatic for uncomplicated mononucleosis.
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cytomegalovirus (CMV)
The virus usually infects salivary gland.
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Pathogenesis; CMV infects salivary gland epithelial cells, fibroblasts and macrophages.
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Disease or Causes; latency in mononuclear cells (most common in utero infection in U.S.)
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Diagnosis; Owl eye inclusion In biopsy material and urine and serology; DNA detection virus culture.
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Treatment; Supportive for healthy patients; ganciclovir foscarnet.
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HHV-6/7
Reservoir: humans
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Transmission: respiratory droplets
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Pathogenesis: replicates in peripheral blood mononuclear cells
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Disease: roseola (exanthem subitum); fever for 3-5 days followed by lacy body rash
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Diagnosis: clinical
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Treatment: symptomatic
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2. HHV-8 (Kaposi sarcoma-associated herpesvirus KSHV)
Reservoir: humans
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Transmission: sexual contact, saliva, vertical, transplantation
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Pathogenesis: gene turns on vascular endothelial growth factor (VEGF); plays direct role in development of
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Kaposi sarcoma; latent in B cells and glandular epithelial cells
Disease: Kaposi sarcoma
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Diagnosis: clinical; serology, PCR
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Treatment: none
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Picornavirus
Picornavirus is a positive sense RNA virus
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Among the smallest,naked and icosahedral of viruses
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a) Enteroviruses; Fecal oral transmission, do not cause diarrhea. (100 Serotypes)
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b) Rhinoviruses; not stable under acidic conditions, growth at 33 C. (100 Serotypes)
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