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HERPES VIRUS 12 LGT-66_882a9fdb0d6913bb7e1a8c57fee8335b.pdf

  1. Herpes viruses =Herpesviridae PROFESSOR DR. SAAD HASAN MOHAMMED ALI Ph. D. VIROLOGY 2022
  2. OBJECTIVES 1.. To preview the virological properties and classification bases of the viral members of Herpesviridae. 2..To list the range of human diseases caused by the two types of Herpes simplex viruses. 3..To list the range of diagnostic methods to differentiate between these two Herpes viral types. 4..To outline the control measures against Herpes simplex viruses.
  3. Classification of Human Herpesviruses
  4. Examples Subfamily Latent Infections Genus Official Name ("Human - Herpesvirus") Common Name Alpha Neurons Simplex 1 Herpes simplex virus type 1 2 Herpes simplex virus type 2 Varicello 3 Varicella- zoster virus Beta Glands, kidneys Cytomegalo 5 Cytomegalo virus Lymphoid tissue Roseolo 6 Human herpesvirus 6 7 Human herpesvirus 7 Gamma Lymphoid tissue Lymphocrypto 4 Epstein-Barr virus Rhadino 8 Kaposi sarcoma- associated herpesvirus HERPESVIRUSES
  5. HUMAN HRPESVIRUSES  (100 Animal species). ( 8 Humans species). Herpes Simplex Virus 1 and 2 (HHV1&2) Varicella-Zoster Virus (HHV3) Epstein-Barr Virus (HHV4) Cytomegalovirus ( HHV5) Human Herpesvirus 6 (HHV6) Human Herpesvirus 7 (HHV7)  Kaposi-Sarcoma Associated- Herpesvirus (KSHV) (HHV8)
  6. Important Properties of Herpesviruses
  7. All= Morphologically Identical: Icosahedral Enveloped Double stranded DNA genome. DNA homology: 1-HSV 1 & 2 (50%) 2- HHV 6 & 7 (30-50%) • Viral-Specific Enzymes= DNA polymerase & Thymidine kinase
  8. All= Morphologically Identical Different herpes viruses cannot be distinguished by electron microscopy Herpes virus particles from human vesicle fluid (X 140,000). (JAWETZ 2019)
  9. All =Characteristic DISEASE: Primary Infection  Latent Infection  Reactivation ((( frequently, but not always, associated with Further disease))).
  10. Some HHVs= Associated with Tumors and Carcinomas HSV-2 Cervical Carcinoma CMV COLONIC CARCINOMA PROSTATIC CARCINOMA CERVICAL CARCINOMA EBV Burkitt's lymphoma Nasopharyngeal Carcinoma HHV-8 Kaposi sarcoma in HIV.
  11. Replication Cycle of Herpes Viruses in General 1- Attachment = Cellular Receptors = Heparan Sulphate 2- Fusion 3- Uncoating  Release of viral DNA 4- Transcription of Alpha genes  Alpha –proteins (Cellular Preparation) 5-Transcription Beta genes  Beta- proteins = (ENZYMES). 6- Viral DNA replication  Viral DNA . 7- Transcription Gamma genes  Gamma – proteins= = Structural Proteins= Empty Capsids Immediate early Early Late
  12. Replication cycle(Continued…) 8- Packaging= DNA into capsids . 10- Accumulation of viral glycoproteins on the nuclear membrane . 11- Get Envelope from nuclear membrane . 12- VIRUSES GO OUT THE CELL through {Endoplasmic Reticulum}
  13. Herpes simplex viruses Background: Ubiquitous, host-adapted pathogens that cause a wide variety of disease states.  Two types exist: Both are closely related but differ in epidemiology. The term herpes is derived from the Greek word “to creep or crawl” Dates back to early Greek civilization, approximately 2000 years ago, in reference to the spreading nature of herpetic skin lesions. ‫مكان‬ ‫كل‬ ‫في‬ ‫موجودة‬
  15. Latent infections for both herpes simplex and varicella-zoster viruses. Primary infections occur in childhood or adolescence, followed by establishment of latent virus in the cerebral or spinal ganglia. Later activation causes recurrent herpes simplex or zoster. Recurrences are rare for zoster. CMI=Cell-Mediated Immunity.
  17. CLINICAL BASES: According To Anatomical Land mark of Waist ??? LESIONS ABOVE WAIST=TYPE 1 LESIONS BELOW WAIST=TYPE 2 Waist HSV 1 HSV 2 1
  18. HSV-1 is traditionally associated with orofacial disease, whereas HSV-2 is traditionally associated with genital disease.  Lesion location, however, is not necessarily indicative of viral type, as HSV-1 is associated with genital infections more often than HSV-2 in some unique subpopulations.
  19. Egg inoculation= Pocks size. DNA Finger Printing= ‫فايروسات‬ ‫من‬ ‫نوع‬ ‫لكل‬ ‫النووي‬ ‫الحمض‬ ‫بصمة‬ • Different Bands Size of The Two Types of HSV- DNA = by doing Restriction Enzymes analysis. Different Serological Reactions No Histopathological discrimination. No CELL CULTURE discrimination No ELECTROM MICROSCOPICAL discrimination 5 2 3 4 6 7 ‫ال‬ ‫بسبب‬ ‫مهمة‬ ‫ليست‬ dna homology
  20. In dermatopathology, the Tzanck test, also Tzanck smear, is scraping of an ulcer base to look for Tzanck cells. It is sometimes also called the chickenpox skin test and the herpes skin test. Tzanck cells (acantholytic cells) are found in: Herpes simplex. Varicella and herpes zoster.
  21. Four herpesviruses: HSV types 1 and 2, VZV, and CMV induce the formation of multinucleated giant cells, which can be seen microscopically in the lesions.
  22. The importance of giant cells is best illustrated by the Tzanck smear, which reveals multinucleated giant cells in a smear taken from the painful vesicles . Arrow points to a multinucleated giant cell with approximately eight nuclei
  23. Oro-pharyngeal dis= ( HSV 1+2) Primary infection {children }: • Fever + sore throat + vesicular & ulcerative lesions(buccal/ gingival ). Primary infection : (adults): *Acute pharyngitis & Acute tonsillitis .. Recurrent lesions : * Border of lip 1
  24. A: Primary herpes simplex gingivostomatitis B: Recurrent herpes simplex labialis
  25. Kerato- conjunctivitis blindness • HSV 1 1- Corneal ulcers . 2- Vesicles lesions on Eye Lids . Genital Herpes : HSV2 usually : * Vesicular & Ulcerative lesions { penis , cervix , vulva, vagina , perineum ) . 2 3
  26. Cutaneous Herpes infection : A.{ Burns = Fatal } + B.{ Eczema = Fatal }. C. General skin infections (primary + recurrent) 4
  27. Eczema Herpeticum A rare but Severe Cutaneous Herpes infection at sites of skin , long term usage burns , atopic dermatitis by= damage produced eczema or topical steroids of
  28. D- Traumatic Herpetic infection : ( Only in abrasions )  Fingers of dentists & hospital personal  Herpetic Whitlow.
  29. Herpetic whitlow Painful, coalescing vesicles with surrounding erythema on fingers history revealed that the patient regularly bit his nails. Positive results on direct fluorescent antibody tests and viral cultures from digital lesions confirmed type 1 HSV infection
  30. 5 Encephalitis : HSV 1 *Most common cause of sporadic fatal encephalitis . ** Usually affecting one brain hemisphere in relation to the side of the affected ganglion with the latent HSV infection
  31. Neonatal Herpes Intra-uterine During birth ( 75%) After birth . • Mortality 50%. * Almost always= Symptomatic. 6 75% HSV 2 25% HSV 1
  32. Neonatal Herpes 3 Categories Localized lesion ( skin ,eye , mouth) Encephalitis +- skin infection Disseminated disease + death (=pneumonitis or DIC)
  33. Severe infections in immunocompromized pts. • HSV1+2 • Spread to respiratory esophageal intestinal tissue & other organs . •Most cases= Reactivated Infections. 7
  34. Lab. Diagnosis 1- Isolation & identification. 2-Typing of HSV-Antigens & Nucleic acid by: A - Monoclonal Abs B- Restriction Enzymes analysis. 3- DNA detection (PCR and ISH) 4- Serology ( IgM IgG Specific for HSV 1&2 )
  35. Immunity HSV 1 & 2 • Passively from the mother to baby ( 1st 6 m). • Primary infection ( 6m – 2 years ) • Anti HSV 1 Abs = child hood & until adolescents • Anti HSV 2 Abs = during adolescence & sexual activity • Abs  Do not prevent re-infection or reactivation ::::::: but modify infection . • Cell Mediated Immunity  Control infection, re-infection & reactivation Geting IgG
  36. Prevention of HSV-1 or HSV-2 : 2…Chemoprophylaxis: Valacyclovir and Famciclovir A… Suppression of recurrent lesions+ frequency of recurrences B…. Reduces shedding of the virus + transmission 3… Operations: - Cesarean section: For women, at term, have genital lesions or positive viral cultures - Circumcision: reduces the risk of infection by HSV-2 1…Avoiding contact: with the vesicular lesion or ulcer Still, No Approved Vaccines against HSV-1 or HSV-2
  37. Treatment of HSV-1 or HSV-2 :: 1. Acyclovir 2. Valacyclovir 3. Vidarabine Effective against HSV Inhibitors of l DNA synthesis.  Suppress clinical manifestations  Shorten healing time  Reduce recurrences of genital herpes.  No effects on latent HSV in sensory ganglia.
  38. THE SUMMARY 1.. Some Herpes viruses have carcinogenic potential in a range of human cancers. 2.. Herpes simplex 1&2 viruses associated with a range of human diseases that are difficult on clinical bases being clearly attributed to a specific type of them. 3..A list of diagnostic facilities can differentiate between these two Herpes simplex types.
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