Medically Important Viruses

These flashcards cover essential facts and details regarding medically important viruses, including transmission methods, symptoms, treatments, and societal impacts.

What type of virus is the Variola virus responsible for Smallpox?

DNA virus, enveloped.

What are the key signs and symptoms of Smallpox?

Fever, malaise in the prodromal stage; pocks all over the body in the eruptive stage.

How is Smallpox transmitted?

Inhalation of saliva droplets or pock crusts, fomites.

What virus causes chickenpox and shingles?

Varicella-Zoster Virus.

What are the major signs and symptoms of infectious mononucleosis caused by the Epstein-Barr virus?

High fever, swollen lymph nodes, extreme fatigue.

What is the primary treatment method for Herpes Simplex Virus infections?

Acyclovir and Valacyclovir.

What does the term 'oncogenic' refer to in relation to Human Papillomavirus (HPV)?

It describes strains of HPV that can cause cancer.

Which strains of HPV are associated with the highest risk of cervical cancer?

HPV 16 and HPV 18.

What vaccination is effective for preventing Measles, Mumps, and Rubella?

MMR vaccine.

What is the site of latency for Herpes Simplex Virus 1 (HSV-1)?

Trigeminal ganglia.

What are the main symptoms of measles?

Systemic skin rash, oral lesions, high fever.

What major complications can arise from Mumps?

Deafness and infertility.

How does Acyclovir work against Herpes viruses?

It inhibits viral DNA synthesis.

What important social implication is associated with the eradication of Smallpox?

Contributed to genocide of Native Americans and Hawaiians.

What is the mode of transmission for the Ebola virus?

Direct contact with bodily fluids of infected individuals.

What is viral latency?

The ability of a pathogenic virus to lie dormant within a host cell, reactivating periodically without being eliminated by the immune system.

What are the common clinical manifestations of HSV-1 infection?

Predominantly oral herpes (cold sores, fever blisters), but can also cause genital herpes or ocular herpes.

How is HSV-1 primarily transmitted?

Direct contact with infected secretions or lesions, often through kissing or shared utensils.

What type of virus is Herpes Simplex Virus 2 (HSV-2)?

DNA virus, enveloped.

What are the common clinical manifestations of HSV-2 infection?

Primarily genital herpes, characterized by painful blisters and ulcers in the genital or anal area; can also cause neonatal herpes.

What is the primary mode of transmission for HSV-2?

Sexual contact with an infected individual during periods of viral shedding.

What is the site of latency for Herpes Simplex Virus 2 (HSV-2)?

Sacral ganglia.

What type of virus is Varicella-Zoster Virus (VZV)?

DNA virus, enveloped, part of the Herpesviridae family (Human Herpesvirus 3 or HSV-3).

What are the characteristic symptoms of chickenpox?

A generalized, intensely itchy rash of fluid-filled blisters (vesicles) that progress to scabs, accompanied by fever and malaise.

What are the characteristic symptoms of shingles (herpes zoster)?

A painful, blistering rash that typically appears in a band or stripe on one side of the body, corresponding to a single dermatome distribution.

How is Varicella-Zoster Virus (VZV) transmitted?

Airborne droplets from respiratory secretions, or direct contact with fluid from blisters.

What is the primary site of latency for Varicella-Zoster Virus (VZV)?

Dorsal root ganglia.

What is the primary treatment for severe Varicella-Zoster Virus infections, such as shingles?

Antiviral medications like Acyclovir, Valacyclovir, or Famciclovir, especially if started early.

What type of virus is Epstein-Barr Virus (EBV)?

DNA virus, enveloped, part of the Herpesviridae family (Human Herpesvirus 4 or HSV-4).

How is Epstein-Barr Virus (EBV) primarily transmitted?

Through saliva, often referred to as the 'kissing disease'.

What is the site of latency for Epstein-Barr Virus (EBV)?

B lymphocytes.

What is the typical treatment for infectious mononucleosis caused by EBV?

Supportive care, including rest, fluids, and pain relievers, as there is no specific antiviral treatment.

What type of virus is Human Papillomavirus (HPV)?

DNA virus, non-enveloped.

What are the common clinical manifestations of HPV infection?

Warts (genital, common, plantar) and can cause cervical, anal, oropharyngeal, and other cancers.

How is Human Papillomavirus (HPV) primarily transmitted?

Direct skin-to-skin contact, particularly sexual contact.

What are the primary treatment options for HPV-related warts?

Topical medications, cryotherapy, electrosurgery, or surgical excision.

What type of virus causes Measles?

RNA virus, enveloped, from the Paramyxoviridae family.

How is Measles primarily transmitted?

Highly contagious airborne droplets from coughing or sneezing.

What is the typical treatment for Measles?

Supportive care, including rest, fluids, and vitamin A supplementation for severe cases.

What type of virus causes Mumps?

RNA virus, enveloped, from the Paramyxoviridae family.

What is the hallmark symptom of Mumps?

Swelling of the salivary (parotid) glands, called parotitis.

How is Mumps primarily transmitted?

Respiratory droplets from coughing, sneezing, or talking.

What is the typical treatment for Mumps?

Supportive care, including pain relief, fever reduction, and rest.

What type of virus causes Rubella (German Measles)?

RNA virus, enveloped, from the Togaviridae family.

What are the main symptoms of Rubella infection?

A mild rash, low-grade fever, and swollen lymph nodes, often less severe than Measles.

How is Rubella primarily transmitted?

Respiratory droplets from talking, coughing, or sneezing.

What is the typical treatment for Rubella?

Supportive care, as the disease is usually mild and self-limiting.

Match the following Herpesviruses with their primary associated disease and site of latency: HSV-1, HSV-2, Varicella-Zoster Virus (HSV-3), Epstein-Barr Virus (HSV-4).

HSV-1: Oral herpes (cold sores); latent in trigeminal ganglia. HSV-2: Genital herpes; latent in sacral ganglia. Varicella-Zoster Virus (HSV-3): Chickenpox, Shingles; latent in dorsal root ganglia. Epstein-Barr Virus (HSV-4): Infectious Mononucleosis; latent in B lymphocytes.

Compare and contrast the typical clinical presentation and causative agents of Genital Herpes and Labial Herpes.

Labial Herpes (cold sores): Usually caused by HSV-1, presenting as blisters around the mouth. Genital Herpes: Primarily caused by HSV-2 (though HSV-1 can also cause it), presenting as painful lesions in the genital area. Both are recurrent, caused by Herpes Simplex Viruses, and treated with antivirals.

Describe the key differences in clinical presentation between Chickenpox and Shingles.

Chickenpox: Primary infection with Varicella-Zoster Virus (VZV), characterized by a widespread, itchy, vesicular rash all over the body. Shingles: Reactivation of latent VZV, presenting as a painful, unilateral, dermatomal rash (often a band-like strip) on one side of the body.

Why can't Acyclovir cure Herpes virus infections?

Acyclovir targets actively replicating viral DNA synthesis, but it does not eliminate the latent viral DNA (episome) stored within host nerve cells. Therefore, the virus can reactivate later.

Name an example of an oncogenic DNA virus.

Human Papillomavirus (HPV).

What does the term 'teratogenic' mean in virology?

Refers to a virus that can cause developmental abnormalities or birth defects in a fetus if the mother is infected during pregnancy.

Name one teratogenic virus.

Rubella virus.

Differentiate between Measles, Mumps, and Rubella based on their primary clinical manifestations.

Measles: High fever, systemic skin rash, Koplik's spots (oral lesions). Mumps: Swollen parotid (salivary) glands (parotitis), fever. Rubella: Mild rash (German Measles), low-grade fever, swollen lymph nodes, often less severe.

What is the MMR vaccine?

A live-attenuated vaccine used to provide immunity against Measles, Mumps, and Rubella (German Measles).