Herpes viruses: Are DNA viruses which include the etiologic agents of herpes simplex,herpes zoster, chickenpox, infectious mononucleosis, and cytomegalic inclusion disease in humans, and of pseudorabies and other animal diseases.

They are dsDNA viruses, enveloped, icosahedra in shape

Causes latent infections with frequent reactivation and viral shedding

All are transmitted by contact except varisella zoster virus (VZV)

Causes cytopathic effect in cell culture (after being infected cells dies, and the died cells may clamp together and form inclusion bodies, cells may be lysed or mutated)

Causes lifelong infections

Varicella zoster virus (VZV) is one of eight herpesviruses known to infect humans.VZV infections are species-specific to humans. It causes chickenpox (varicella), a disease most commonly affecting children, teens and young adults and herpeszoster (shingles) in older adults; shingles is rare in children.

Chickenpox, also known as varicella, is a highly contagious disease caused by the initial infection with varicella zoster virus (VZV). The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab over.

Shingles is a viral infection that causes a painful rash. Although shingles can occur anywhere on your body, it most often appears as a single stripe of blisters that wraps around either the left or the right side of your torso. Shingles is caused by the varicella-zoster virus — the same virus that causes chickenpox

Herpes viruses are viruses that cause latent infections. It can stay in the body without causing signs and symptoms until the host immunity gets reduced like in HIV situation.

Examples of herpes viruses of medical importance include

Herpes simplex viruses 1 & 2 (HSV 1 & HSV 2)

Cytomegaloviruses

Epstain bar viruses

Human herpes virus 6

Human herpes virus 8 (Kaposis Sarcoma virus)

Diseases caused by Herpes simplex 1 are

Herpes labialis

Herpes labialis is characterized by fever blisters on the mouth or face, keratisitis, and encephalitis

Genital blisters

By antibody neutralization of florescent antibody test (compliment fixation test)

Drug of Choice (for Palliative Care)

Acyclovir tablets

Acyclovir cream/ ointment

Trifluorothymidine

Iudoxuridine

Diseases caused by Herpes simplex 2 are

Genital herpes (blisters occurring below the waist)

Aseptic meningitis (non – bacterial inflammation of meninges)

Neonatal herpes (Infection to neonates that occur during birth)

Herpes labialis

Identifying cytopathic effect in tissue culture

Antibody neutralization of florescent antibody test (compliment fixation test)

Drug of Choice (for Palliative Care)

Acyclovir tables

Acyclovir cream/ointment

Cytomegalovirus (CMV) is a virus found around the world…. Between 50 percent and 80 percent of adults in the United States have had a CMV infection by age 40…. But infection with the virus can be serious in babies and people with weak immune systems.

Cytomegalovirus (CMV) is a common virus that can infect almost anyone. Most people don’t know they have CMV because it rarely causes symptoms. However, if you’re pregnant or have a weakened immune system, CMV is cause for concern.

Once infected with CMV, your body retains the virus for life. However, CMV usually remains dormant if you’re healthy.

CMV spreads from person to person through body fluids, such as blood, saliva, urine, semen and breast milk. CMV spread through breast milk usually doesn’t make the baby sick. However, if you are pregnant and develop an active infection, you can pass the virus to your baby.

There’s no cure for CMV, but drugs can help treat newborns and people with weak immune systems.

Cytomegalo virus (CMV) causes a number of diseases characterized by enlargement (ballooning) of the infected host cells

The diseases include

Pneumonia and hepatitis in immune-compromised patients

Retinitis and enteritis especially in AIDS patients

Cytomegalic inclusion body disease in infants

Mononucleosis in transfusion recipients

Cytopathic effect in tissue culture (cell enlargement)

“Owls eye” nuclear inclusions are seen in cell culture

Serum for serological tests to determine rise in antibody titer

Treatment

Ganciclovir

Typical Morphology of CMV: The Circled Area Shows Owls Eye Appearance ofCMV in Infected Cells as Seen in Electron Microscope in a Special Staining

Diseases caused by Epstein bar virus are

Burkitts lymphoma in East African children (occurs as a tumor of the face and jaw and sometimes as an abdominal tumor) in East African children

Burkitts Lymphoma is associated with high endemicity of Plasmodium falciparum

Infectious mononucleosis

The Epstein–Barr virus, also called human herpes virus 4, is one of eight known viruses in the herpes family, and is one of the most common viruses in humans. It is best known as the cause of infectious mononucleosis

Tumor aspirates

Full blood picture

Drug of Choice

No effective drugs is available

Disease they cause: Kaposi’s sarcoma especially in AIDS patients

Laboratory diagnosis: Biopsy for pathological examination of cells

Drug of choice: No specific antiviral treatment

Kaposi’s sarcoma-associated herpesvirus is the eighth human herpesvirus; its formal name according to the International Committee on Taxonomy of Viruses is HHV-8

Herpes viruses are characterized by latency infections

They cause lifelong infections

All Herpes virus are DNA viruses

Herpes viruses includes Herpes simplex viruses type 1&2, Human Herpes Virus type 6, Human Herpes Virus type 8, Cytomégalovirus and Epstein Bar virus (EBV)

What are Herpes viruses?

What are the disease caused by Herpes simplex 1 and 2?

List four viruses which cause latent infections

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