Herpes viruses. Adenoviruses. Biological properties, pathogenecity for humans. Laboratory...

Herpes viruses. Adenoviruses. Biological properties,

pathogenecity for humans. Laboratory diagnostics,

prophylaxis and therapy of diseases.

Vinnitsa National Pirogov Memorial Medical University / Department of microbiology

Herpes viruses. Classification1. Alphaherpesvirinae includes next species

1. Herpes simplex viruses 1 and 2 (HSV1 and HSV2)

2. Varicella-zoster virus (VZV or HHV 3)

2. Betaherpesvirinae contains species

1. Cytomegalovirus (CMV or HHV 5)

2. HHV6 and HHV7

3. Gammaherpesvirinae includes species

1. Epstein-Barr virus (EBV or HHV4)

2. Kaposi`s sarcoma associated virus (HHV8)

Herpes viruses

Herpes simplex virusThere are two types of the herpes

simplex virus (HSV):

1.HSV type 1 causes herpes labialis

2.HSV type 2 causes herpes genitalis

Cultivation of the HSV1. Chick embryo

2. Cell cultures

3. Experimental keratoconjunctivitis

Epidemiology and pathogenesisThe source of infection is ill person with typical lesionsInfection is transmitted by close direct contact (labial

herpes) or sexual intercourse (genital herpes)

Laboratory diagnosticsMicroscopy:

CytoscopyImmune electron microscopyImmunofluorescence

Virus isolation

Serology

Varicella-zoster virus (VZV)

causes chickenpox after primary infection and herpes zoster

The source of infection is person with chickenpox or more rarely with herpes zoster

Infection is transmitted with air droplets (chickenpox) or with direct contact with lesions

Varicella (chickenpox) Herpes zoster

Pathogenesis of varicella/zoster infection

Laboratory diagnostics

Microscopy:Tzanck smear Immune electron microscopyImmunofluorescence

Virus isolation Serology

Prevention is possible by active immunization with live, attenuated VZV (OKA strain)

For contact person varicella-zoster immunoglobulin (VZIG) is used to prevent disease

Cytomegalovirus (CMV)In persons with adequate immunity CMV

causes subclinical or unapparent infection.In persons with waned immunity CMV can

provoke generalized infection.Congenital CMV-infection often is very severe,

associated with hepatosplenomegaly, jaundice, hemolytic anemia, and microcephaly, chorioretinitis

Cells infected by CMV

Laboratory diagnosticsRapid diagnostics

Virus isolation

Serological method

Epstein-Barr virus (EBV)It belongs to gamma-herpes viruses (HHV-4) and has

oncogenic properties.It can cause different diseases from latent infection in

children, infectious mononucleosis in adulthood to EBV-associated malignancies such as Burkitt`s lymphoma and nasopharingeal carcinoma

Laboratory diagnostics1. Blood assay

2. Serological tests are used to reveal: Heterophile antibodies with Paul-Bunnell test Specific anti-EBV antibodies with ELISA and

immunofluorescence

AdenovirusesThey belong to family Adenoviridae, genus

Mastadenovirus divided into 7 serogroups (A-F) and 47 serotypes

Adenovirus structure

Pathogenecity 1. Respiratory disease in children (pharyngitis,

pneumonia)

2. “Common cold” in adults

3. Conjunctivitis (swimming pool follicular conjunctivitis and keratoconjunctivitis -shipyard disease)

4. Diarrhea in children

5. Acute hemorrhagic cystitis in young males

Epidemiology and pathogenesisAdenoviruses are transmitted with different

mechanisms:

1.Via aerosol droplets

2.With fecal-oral route

3.By direct contact

Laboratory diagnosticsDiagnosis is based onto:

1.Rapid diagnostics with electron microscopy, immune electron microscopy, immunofluorescence

2.Virus isolation

3.Serological tests demonstrate rising in titer of antibody, demonstrated in paired patient sera