Uploaded Herpes Virus

HERPES VIRUS Classification Subfamily Alpha Herpesvirinae

Beta Herpesvirinae

Common Name Herpes simplex type - 1 Herpes simplex type - 2 Varicella zoster Human cytomegalovirus

Gamma Herpesvirinae

Epstein Barr virus

Scientific Name Human herpes virus 1 Human herpes virus 2 Human heroes virus 3 Human herpes virus 5 Human herpes virus 6 Human herpes virus 7 Human herpes virus 4 Human heroes virus 8

Structure: • Enveloped • Icosahedral capsid • DsDNA • All members can be cultured in cell cultures except Epstein Barr virus

HERPES VIRUS TYPE -1 (Herpes Simplex Virus) a) Primary Infection (generally acquired at 6 months to 3 years of age through eye or oral mucous membranes, usually asymptomatic but 10-115% may show acute gingivostomatitis) b) Latent infection (Viral DNA persists as free episome in neural cells despite high antibody titres) c) Reactivation (recurrent infections are common, e.g. recurrent Herpes labialis) HSV - 1

HSV - 2

Above Waist: Below Waist: • Gingivostomatitis • Genital Herpes • Keratoconjunctivitis • Aspetic Meningits • Eczema herpeticum • Neonatal infection Encephalitis Generalized infection Type 16,18,31 20% of total cases of genital infection Cervical carcinoma Herpetic whitlow Occupational Hazards from patient to doctors & nurses vesicles on head & neck Tzanc smear (can’t differentiate between different strains of Herpes Virus) • Ballooning of cells • Ground glass nuclei • Multinucleated giant cells • Eosinophilic intranuclear Inclusion bodies known as "Cowdry type A" Treatment Acyclovir - reduction of DNA synthesis

(Varicella zoster) Human Herpes Virus - 3 Complications: • Pneumonitis • Encephalitis • GB syndrome • Reye's syndrome

On Micros copic Exami nation of base of lesion-

• Congenital malformation (If infection occurs in 1st trimester of pregnancy) a) Bypoplasia oflimbs b) Chorioretinitis c) Scarring of skin Vaccine – Made from live attenuated OKa strain of virus grown in MRC5 human diploid cell culture, gives lasting immunity.

Epstein Barr Virus / Human Herpes Virus -4 Clinical manifestations: • Infectious mononucleosis / Glandular fever • X - linked lymphoproliferative syndrome • Progressive lympoproliferative disease in transplant recipients, immunodeficient and AIDS patients • Burkitt's lymphoma (malignant neoplasm of B lymphocytes, primarily occurs in young children and young adults of South Africa where malaria is hyper-endemic) • Nasopharyngeal carcinoma • B cell lymphoma in transplant recipients & AIDS patients • Oral Hairy luekoplakia in HIV +ve • Lymphocytic interstitial pneumonitis in HIV +ve children LAB Diagnosis: I. Leucocytosis:10,000 - 20,000/cu mm with 80% lymphocytes + monocytes and 20% of thus being atypical lvmphocytes (with segmented nucleus) II. Paul- Bunnell test to detect Heterophile Antibodies Heterophile IgM Antibodies- Aggregation of sheep or Horse RBCs Patients serum is adsorbed first with guinea pig kidney cells to remove forssman antibodies which can otherwise cause false agglutination III. EBV specific IgM Antibodies - by ELISA, Immunoflourescence method IV. Virus Isolation: From Saliva, Throat washings/Peripheral blood leucocytes Inoculated on umbilical lymphocytes Immortalization of these cells by transformation to a lympho-"blastoid" cell line o EBV replicates in epithelial cells of nasopharynx + salivary glands o EBV infects B. lymphocytes but does not replicate in them exist as free episomes (multiple copies) and some of them undergo transformation.

Cytomegalovirus CMV (Human Herpes Virus - 5) • • • •

Replicates in epithelial cells of salivary glands, kidneys & respiratory epithelium Infected person carries the virus for life Secreted in all body secretions Present in 0.3 - 2.4% of population

Prenatal Infection Most common Agent to cause intrauterine infection of foetus. Only 5% of infected foetus are symptomatic at birth and develop "Cytomegalic Inclusion Body disease" causing: • Growth Retardation • Hepato-splenomegaly • Jaundice • Thrombocytopenia

• Microcephaly, Encephalitis • Chorioretinitis Remaining 95%; About 15% develop Mental Retardation and Deafness. Perinatal Infection- By vaginal secretions or breast feeding. Post natal- Close Contact / Kissing / Sexual / BT / Organ transplantation, Pneumonia, Chorioretinitis, Hepatitis, arthritis, Glomerulonephritis, Encephalitis, GB syndrome Lab Diagnosis I. Virus isolation - In cultured human fibroblasts CPE - Multinucleated giant cells with I/C & I/N eosinophilic I.B. II. Serology - IgM Antibodies by ELISA III. Virus DNA - By PCR Treatment: Ganciclovir

Human Herpes Virus – 6 & Human Herpes Virus - 7 • • • •

Infects CD4, T lymphocytes & Macrophages Reservoir - Salivary Glands Causes Exanthema subitum / Roseola infantum Causes Mononucleosis with cervical lymphadenopathy

Human Herpes Virus -8 Kaposi's sarcoma Herpes B virus / Herpes V. simiae / Cercopilthecine Herpes virus I. Natural infection in monkeys - resembles herpes simplex type - I clinically II. Accidental infection in humans - by handling monkeys or monkey kidney cell cultures III. Can lead to ascending myelitis