1. 1 30/11/98 Herpes Viruses Cytomegalovirus

2. 2 30/11/98 Presentation Outline  Structure  Classification  Multiplication  Clinical manifestations  Epidemiology  Diagnosis  Control

3. 3 30/11/98 Latent Infections  ALL herpes viruses can establish latent infections. The viral genome may become incorporated into the host DNA or remain extrachromosomal  Latent viruses can be reactivated by stress, menstruation or uv light  Reactivation may be asymptomatic or lead to mild or severe disease.

4. 4 30/11/98 Herpes Diagnosis  Isolation of virus by tissue culture  herpevirinae cause cytopathic effects  intranuclear fluorescence of scrapings using fluorescent antibodies  PCR being developed CMV retiniitis is diagnosed clinically

5. 5 30/11/98 Cytomegalovirus

6. 6 30/11/98  Cytopathic effect on the host cell. The cell swells and a large inclusion body forms in the nucleus.  Transmission:  not highly infectious, virus found in saliva, urine and blood.  infants and children acquire CMV from other children.  congenital. In utero, at birth during perinatal period.  see clinical note in the textbook.  Clinical forms of Cytomegalovirus infection  Congenital:  the following possibilities relate to the congenital type.  severe deformities and death.  survive with serious defects - physical and mental.  survive with out deformities.  newborns: - Enlarged liver and spleen, jaundice, capillary bleeding, microcephaly, ocular inflammation.

7. 7 30/11/98 Disseminated cytomegalovirus  Symptoms:  fever, severe diarrhea, hepatitis, arthritis, pneumonia, high mortality.  activation of inapparent infection.  also due to: ä immunosuppressive therapy. ä cancer. ä AIDS.  Virus in blood or organ:  post transfusion.  post organ transplant.  Cytomegalovirus mononucleosis:  teenage, young adult similar to other mono.

8. 8 30/11/98 Epidemiology of CMV  whereever human populations tested - high percentage (40-100%) were positive for the antibodies.  newborns 7.5% positive in the USA & UK.  woman of child bearing age were 20-100% positive in many countries that were studied (pregnant - virus in the urine).  IV drug users were 100% positive for the antibodies.  homosexual males were 30% positive for the antibodies - high percentage shed virus.  Transmission:  saliva, respiratory mucus, milk, urine, semen, cervical secretions, feces and lymphocytes.  Diagnosis:  the differential diagnosis in neonates must include toxoplasmosis, rubella, herpes simplex, bacterial sepsis.  in adults it must be differentiated from Epstein-Barra and hepatitis A & B.

9. 9 30/11/98 Cytomegalovirus - con’t  Laboratory diagnosis:  virus can be grown from all organs.  many serological tests.  Treatment:  gancyclovir, foscarnet, hyperimmune CMV immunoglobulin, have some effect.  interferon does not prevent infection or promote recovery.  Prevention:  no animal can be found that can be infected with CMV.  Two deterents:  vaccine stimulated antibodies may not be protective. Patients already seropositve can be reinfected.  a vaccine could be oncogenic.

10. 10 30/11/98 EBV and burkitt’s lymphoma were shown to be the same virus when a lab technician acquired mononucleosis while working with the Burkitt’s lymphoma virus.

11. 11 30/11/98 Cytomegalovirus  Urine isolate

12. 12 30/11/98 Intranuclear inclusions  The cell swells and a large inclusion body forms in the nucleus.

13. 13 30/11/98 Cytomegalovirus  Nuclear & cytoplasmic inclusions

14. 14 30/11/98 Transmission: CMV  not highly infectious, virus found in saliva, urine and blood.  infants and children acquire CMV from other children.  congenital. In utero, at birth during perinatal period.

15. 15 30/11/98 Congenital: CMV  the following possibilities relate to the congenital type.  severe deformities and death.  survive with serious defects - physical and mental.  survive with out deformities.  newborns: - Enlarged liver and spleen, jaundice, capillary bleeding, microcephaly, ocular inflammation.

16. 16 30/11/98 Disseminated cytomegalovirus  fever, severe diarrhea, hepatitis, arthritis, pneumonia, high mortality.  activation of inapparent infection.  also due to: - immunosuppressive therapy. - cancer. - AIDS.

17. 17 30/11/98 Virus in blood or organ:  post transfusion.  post organ transplant.

18. 18 30/11/98 Cytomegalovirus mononucleosis:  teenage, young adult similar to other mono.

19. 19 30/11/98 Epidemiology of CMV  high percentage (40-100%) were positive for the antibodies.  newborns 7.5% positive in the USA & UK.  woman of child bearing age were 20-100% positive in many countries that were studied (pregnant - virus in the urine).  IV drug users were 100% positive for the antibodies.  homosexual males were 30% positive for the antibodies - high percentage shed virus.

20. 20 30/11/98 Transmission:  saliva, respiratory mucus, milk, urine, semen, cervical secretions, feces and lymphocytes.

21. 21 30/11/98 Differential Diagnosis:  the differential diagnosis in neonates must include toxoplasmosis, rubella, herpes simplex, bacterial sepsis.  in adults it must be differentiated from Epstein-Barra and hepatitis A & B.

22. 22 30/11/98 Laboratory diagnosis: CMV  virus can be grown from all organs.  many serological tests.

23. 23 30/11/98 Treatment: CMV  gancyclovir, foscarnet, hyperimmune CMV immunoglobulin, have some effect.  interferon does not prevent infection or promote recovery.

24. 24 30/11/98 Prevention:CMV  no animal can be found that can be infected with CMV.  Two deterents:  vaccine stimulated antibodies may not be protective. Patients already seropositve can be reinfected.  a vaccine could be oncogenic.