MODULE 4 MYCO VIRO

• Adenovirus


  Cause acute respiratory diseases (common colds)
• Adenovirus


  Named after adenoids from which they were first isolated
• Adenovirus


  Double stranded DNA, could be hexon or pentone
• Adenovirus pathogenesis


  1. Spread by aerosol, close contact, or fecal-oral route

  2. Virus infects first mucoepithelial cells causing direct cell damage

  3. Virus persists in the lymphoid tissue

  4. Disease is determined by the tissue tropism of a virus

  
• Adenovirus clinical syndromes

  • Acute febrile pharyngitis
  • ARD
  • Pharyngoconjunctival fever
  • Epidemic keratoconjunctivitis
  • Infant diarrhea
  • Acute hemorrhagic cystitis
  • Systemic infection (immunocompromised)
• Adenovirus lab diagnosis

  • Electron microscopy
  • HEK/Hep-2
  • Serology
• Adenovirus treatment

  • Supportive
  • Vaccine (serotype 4 & 5 for military recruits)
• Herpesviridae

  • HSV-1
  • HSV-2
  • VZV
  • EBV
  • CMV
  • Herpes lymphotropic virus
  • HH6/HH7
  • HH8

  
• Herpes type 1 (oral herpes)


  Cause sores around the mouth and lips (sometimes called fever blisters or cold sores), can also cause genital herpes
• Herpes type 2 (genital herpes)


  Most genital herpes are caused by Herpes type 2
• Herpes lab diagnosis


  • Cytology/ Histology
  • Culture
  • EIA, FA stain
• Herpes treatment


  • Acyclovir
• Herpes prevention


  • Avoid contact
• Alpha herpesviruses


  • Short reproductive cycle
  • Latent in sensory neurons
  • Painful skin disease
• Beta herpesviruses

  • Long reproductive cycle
  • Latent in WBCs
• Gamma herpesviruses

  • Latent in lymphocytes
  • Associated with cancer
• Varicella-Zoster Virus (VZV)


  Human alphavirus 3 (HHV-3), causes chickenpox or varicella, and shingles (herpes zoster)

  
• Chickenpox/Varicella


  • Fever and maculopapular rash, dew drop rose petal
  • Within 12 hours → vesicles → pustule → crust → scabbed lesion
  • Severe in adult than in children

  
• Herpes-Zoster


  • Unilateral (one or more adjacent dermatomes)
  • Post herpetic neuraglia = chronic pain syndrome
• Dermatomes


  Areas of the skin supplied by sensory fibers of the spinal nerves
• VZV lab diagnosis


  • FA stain
  • HDF
  • Shell vial culture
• VZV treatment


  • Acyclovir
  • Famciclovir
• VZV vaccine


  • VZIG
  • Zoster immune plasma
• In 1958, Burkitt first described a malignant lymphomatous disease which affected children and occurred with peculiarly high frequency in central and west Africa

  
• Burkitt's lymphoma


  Neoplasm frequently involved the jaw and abdomen, had a characteristic "starry sky" appearance, showing diffuse, primitive, poorly differentiated, large immature cells of lymphoblastic type

  
• Epstein Barr Virus (EBV)

  Associated with Burkitt's lymphoma, nasopharyngeal carcinoma and infectious mononucleosis (IM)
• EBV clinical syndromes


  • Infectious mononucleosis
  • Chronic fatigue syndrome
  • Progressive reticular disease
  • Oral hairy leukoplakia
  • Burkitt's lymphoma
  • Nasopharyngeal carcinoma

  
• EBV lab diagnosis


  • Atypical lymphocytes
  • Heterophil antibody
  • Serology
• EBV treatment


  • Supportive
• Atypical lymphocytes


  Lymphocytes that have been activated to respond to a viral infection or sometimes a bacterial or parasitic infection
• Cytomegalovirus (CMV)


  Common and usually mild viral illness, rarely causes symptoms in healthy people, but can cause complications in immunocompromised and pregnant women
• CMV prevalence


  0.5 TO 1.0 of all newborns, 50% adult population
• CMV transmission


  • Close contact with infected secretions
  • Blood transfusions
  • Organ transplant
  • Transplacental
• CMV lab diagnosis


  • Cytology
  • Histology
  • Cell culture
  • Antigen detection
  • Molecular probe
  • Serology
• CMV treatment


  • Supportive
  • Decrease immune suppression
  • Foscarnet
  • Glanciclovir
• HHV 6 and HHV 7

  Transmitted via respiratory route, site of latency is CD4 cells, cause roseola (exanthem subitem) and associated with immunocompromised patients

  
• HHV 6 and HHV 7 treatment

  • Glanciclovir
  • FOSCARNET
• HHV 6 and HHV 7 diagnosis

  • PCR
  • Cell culture lymphocyte lines

  
• HHV 8


  Mode of transmission not known, site of latency is kaposis tumor cells, causes kaposis sarcoma

  
• HHV 8 diagnosis


  • PCR or in aitu hybridization