Herpes Flashcards
What are the 4 component of the structure of herpes?
1) Envelope
2) Tegument (protein)
3) Capsid
4) Genome
What is the capsid?
What type of genome?
How does it enter?
- Herpesviridae have enveloped icosahedral capsids.
- Linear ds DNA
- Attaches to cell’s receptor and enter fell through fusion.
T/F: Herpes can have latency.
True. Remain inactive inside infected cells. Can reactivate causing recurrence of disease.
What are the 4 genera of herpesviridae?
1) Simplexvirus (most virulent)
2) Varicellovirus
3) Lymphocryptovirus
4) Cytomegalovirus
5) Roseolovirus
How many human herpesvirus?
Eight. Number according to number discovered.
First 2 are simplexviruses.
How is herpes virus released?
By budding. Buds out of the nuclear membrane first. Then it is exocytosis outside of cell.
What is the usual source of infection?
Active lesions. Transmission through close bodily contact.
Asymptomatic carriers can shed _ _ - genitally.
HSV-2.
Where do viruses enter?
Through cracks, cuts in mucous membranes.
What happens to skin lesions?
Inflammation. Cell death at site of infection.
How can herpes spread from cell to cell?
Through formation of syncytia.
What is true latency?
Virus enters into a cell and stays dormant, do not replicate.
What is clinical latency?
Virus replicating at low level.
Where do the HSV-1 stay dormant?
Trigeminal nerve ganglion and Brachial ganglia.
What is whitlow?
On fingers.
What is karatitis?
Eyes.
What is gladiatorum?
Neck.
What do topical applications do to the virus?
Limit duration of the lesions and reduce viral shedding. Drugs do not cure or free nerve cells of latent viral infections.
Varicella-Zoster Virus (VZV) causes what 2 diseases?
1) Varicella - chicken pox (children)
2) Herpes zoster - shingles (adults)
How does VZV enter body?
Enters skin through respiratory tract and eyes.
How does VZV travel?
Replicate at site of infection and travel through blood.
What is characteristic of shingles?
Rash localized along a dermatome - dorsal roots from the spine.
What is EBV or HHV-4? What disease does it cause if you lack immune system? What about poor?
Epstein-Barr. Cause different diseases depending on cellular immunity status.
Lacking immunity would cause ORAL HAIRY LEUOPLAKIA.
Poor is burkitts lymphoma.
What are associations of burkitts lymphoma?
1) Endemic variant, in africa, chronic malaria.
2) Sporadic type. non-african, small intestine.
3) Immunodeficiency-associated. HIV
Causes chronic fatigue.
What type of cancer does burkitts lymphoma cause?
Nasopharyngeal cancer.
What results from EBV from vigorous immune response? (Hyperactive immune response)
Atypical lymphocytes. Results in infectious mononucleosis.
How are EBV transmitted?
Saliva.
What cells do EBV virions infect?
Epithelial cells of pharynx and parotid salivary glands.
How does EBV travel in body and invades what cells?
Enters bloodstream. Invades B lymphocytes.
Where is EBV latent? How do these cells become immortalized?
Latent in b cells and immortalize by suppressing apoptosis.
Why do the symptoms of mononucleosis arise?
Cytotoxic t cells kill virus infected b lymphocytes.
What is the 5th herpes? What happens to infected cells?
CMV - Cytomegalovirus. cells become enlarged.
How is CMV transmitted?
Through bodily secretions. Require close contact and large exchange of secretion (sex).
Also transmitted by utero exposure, vaginal birth, blood transfusions, organ transplants.
T/F: Most CMV infections are asymptomatic.
True.
Who develops complications to CMV? What’s different about CMV causing mono than EBV?
Fetuses, newborns, immunodeficient patients. CMV can cause birth defects, even death.
CMV causes mono, but heterophile ab is not produced. Where heterophile is produced in EBV.
T/F: CMV causes infectious mononucleosis heterophile ab not produced.
True.
What is HHV-6? Causes what symptom?
Genus roseolovirus. Pink rash on face, neck, trunk, and thighs. Also cause mononucleosis-like symptoms.
What does HHV-6 make individuals more susceptible to?
AIDS.
What is HHV-8 associated with?
Associated with Kaposi’s sarcoma, cancer seen in AIDS patients. Virus is not found in cancer-free patients or in normal tissues of victims.
1) HSV 1
2) HSV2
3) VZV
4) EBV
5) CMV
6) HHV-6 major
7) HHV-6 minor
8) KS
1) Cold sores
2) Genital
3) Chicken pox/shingles
4) Epstein-Barr
5) Cytomegalovirus
6) Roseolovirus
7) Roseolovirus
8) Kaposi’s sarcoma
