Virology Quiz: Influenza and Herpes Viruses

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Questions and Answers

Which characteristic is not consistent with a virus?

Possesses its own enzymes for replication. (correct)

Can reproduce only inside a living host cell.

Utilizes the host's DNA and RNA for replication.

Requires host cell substrates for viral replication.

What is the primary mode of transmission for influenza?

Through contaminated food and water.

Through the air via respiratory droplets. (correct)

Via direct physical contact with an infected person.

Through vectors such as mosquitoes or ticks.

Which influenza antigen type is most likely to cause a moderate to severe illness?

Type B

Type C

All types equally cause severe illness

Type A (correct)

What is the typical time frame during which influenza virus replication begins before symptoms appear?

24 hours before symptoms appear (D) Signup and view all the answers

Which of these is an atypical initial symptom of influenza?

Productive cough (A) Signup and view all the answers

Which bodily fluid is NOT a known source of Hepatitis B virus transmission?

Saliva (C) Signup and view all the answers

A patient with Hepatitis B is experiencing jaundice, malaise, and myalgia. Which is NOT typically seen in this type of viral infection?

Constipation (B) Signup and view all the answers

What is the primary action of antiviral medications in the treatment of viral infections?

Interfering with the virus's ability to replicate within the cell (A) Signup and view all the answers

Which characteristic is MOST associated with herpes simplex virus type 1 (HSV-1)?

Cold sores. (C) Signup and view all the answers

What is characteristic of the latent phase of herpes simplex viruses?

Maintenance of disease potential without signs and symptoms. (D) Signup and view all the answers

Which antiviral medication is commonly used to treat cytomegalovirus (CMV) retinitis, especially in patients with AIDS, but requires close monitoring for kidney damage?

Cidofovir (C) Signup and view all the answers

What is a common route of transmission for herpes simplex type 2 (HSV-2)?

Through intimate sexual contact. (B) Signup and view all the answers

A patient is prescribed Amantidine HCl for Type A influenza. Which of the following side effects would the nurse monitor the patient for?

Insomnia, anxiety, and ataxia (B) Signup and view all the answers

Where does Herpes Simplex Virus type 2 (HSV-2) typically establish latency?

In the sacral dorsal root ganglia. (A) Signup and view all the answers

What are the initial signs/symptoms of herpes simplex virus infection?

Eruption of small pustules and vesicles, fever, headache, malaise, myalgia, tingle, itching, and pain. (B) Signup and view all the answers

What characteristic is shared by both HSV-1 and HSV-2?

They can both cause recurrent infections. (C) Signup and view all the answers

How are herpes simplex viruses generally transmitted?

Through contact with infectious lesions or secretions (A) Signup and view all the answers

Besides oral sex, what is another way that a herpes virus transmits from the mouth to the genital area?

Through poor handwashing practices. (B) Signup and view all the answers

Which herpesvirus is known for causing both chickenpox and shingles?

Varicella-zoster virus (HSV-3) (C) Signup and view all the answers

A characteristic symptom of chickenpox is:

Generalized pruritic vesicles and fever (B) Signup and view all the answers

What is the primary difference between chickenpox and shingles regarding the varicella-zoster virus?

Shingles is a reactivation of a dormant virus in nerve cells. (B) Signup and view all the answers

Which of the following is a common symptom associated with infectious mononucleosis caused by the Epstein-Barr virus (EBV)?

Fever, tonsillitis, and enlarged lymph nodes in the neck (D) Signup and view all the answers

Where can the Epstein-Barr virus (EBV) reside in the human body?

In the lymphocytes, epithelial cells, and muscle cells (C) Signup and view all the answers

Under what circumstances does a Cytomegalovirus (CMV) infection typically require medical treatment?

When an individual is immunocompromised (D) Signup and view all the answers

Which of the following is NOT a reported mode of Cytomegalovirus (CMV) transmission?

Through airborne droplets in crowded area. (B) Signup and view all the answers

What is a potential severe complication of a Cytomegalovirus (CMV) infection in compromised patients?

Fatal pneumonia or blindness (B) Signup and view all the answers

Which medication is specifically used to treat recurrent herpes labialis?

Penciclovir (C) Signup and view all the answers

What is the primary function of neuraminidase inhibitors?

To decrease the release of the virus from infected cells (C) Signup and view all the answers

Which of the following is a characteristic of gamma globulin?

It contains preformed antibodies that provide passive immunity (A) Signup and view all the answers

Which medication is used to treat RSV in children?

Ribavirin (A) Signup and view all the answers

What should be closely monitored when a patient is taking Valacyclovir?

Kidney function (D) Signup and view all the answers

For which of the following conditions is valganciclovir indicated?

CMV retinitis in AIDS patients (C) Signup and view all the answers

What is the primary target of HIV?

CD4+ T cells (B) Signup and view all the answers

How is the "window period" described in the context of HIV?

The time it takes for a positive HIV test result after exposure (D) Signup and view all the answers

What is a key indicator for immune function in HIV patients?

CD4 cell count (C) Signup and view all the answers

Which of these is the goal of antiretroviral therapy (ART) regarding viral load?

To achieve and maintain a viral load below the limits of detection (A) Signup and view all the answers

Which medication is used for prophylaxis against influenza types A and B?

Influenza virus vaccine (C) Signup and view all the answers

Which class of drugs interferes with viral DNA synthesis?

Purine nucleosides (D) Signup and view all the answers

What is the primary action of human immune globulin?

Providing pre-formed antibodies for passive immunity. (C) Signup and view all the answers

Which medication is commonly used for treating chronic hepatitis B virus?

Telbivudine (D) Signup and view all the answers

Which effect does probenecid have when administered with acyclovir?

Increased effectiveness of acyclovir (A) Signup and view all the answers

Study Notes

Antivirals

Antivirals are used to prevent or delay the spread of viral infection
They inhibit viral replication by interfering with viral nucleic acid synthesis in the cell

Virus

Intracellular organisms needing a living host to survive and reproduce
They enter healthy cells and use their DNA and RNA to create more viruses
Growth depends on host cell enzymes and substrates for viral replication
Viruses live and reproduce within living cells
Examples of viral infections include influenza, herpes viruses, and viral hepatitis

Viral Infections: Influenza

Highly contagious, affecting the nose, throat, and lungs
Three antigen types: A (moderate to severe infection), B (mild illness in children), and C (rare)
Spread through droplets from coughing, sneezing, or talking
Replication starts 24 hours before symptoms appear, with initial symptoms including headache, fatigue, and myalgia
Other symptoms include sore throat, nonproductive cough, watery nasal discharge, weakness, red watery eyes, chills, and photophobia
Diagnosed through throat swabs, nasal swabs, or nasal aspiration

Viral Infections: Herpesviruses

Large viruses causing infections
Type 1 (HSV-1): Commonly associated with oral cold sores (vesicular lesions) that grow in neurons. Capable of latency, maintaining disease potential without symptoms. Spread by oral secretions, potentially to the genitals via oral sex or poor handwashing.
Type 2 (HSV-2): Associated with genital herpes, vesicular lesions and small ulcerations on the genitalia. Remains dormant in nerve cells, travelling through the peripheral nerves to the sacral dorsal root ganglia. Spread during intimate sexual contact.
Symptoms: Eruption of small pustules and vesicles, fever, headache, malaise, myalgia, tingling, itching, and pain in the affected area.

Viral Infections: Varicella-zoster Virus (HSV-3)

Known as chickenpox or shingles.
Chickenpox: Highly contagious, causing generalized pruritic vesicles (fluid-filled blisters) and fever. Dormant in nerve cells.
Shingles: Can reactivate in older people or those with weakened immune systems, with rash formation and fever, malaise, and myalgia.

Viral Infections: Epstein-Barr Virus (EBV, HSV-4)

Common cause of infectious mononucleosis (kissing disease)
Symptoms include fever, tonsillitis, and enlarged lymph nodes in the neck
Resides in lymphocytes, epithelial cells, and muscle cells with a latency period

Viral Infections: Cytomegalovirus (CMV, HHV-5)

Very common infectious disease
Treatment is not usually necessary unless the patient is immunocompromised.

Viral Infections: Hepatitis B (HBV)

Serious liver infection caused by a hepatitis B virus
Spread via needlestick injury, intimate sexual contact, and childbirth
Occurs in bodily fluids like blood, semen, and vaginal fluid
Symptoms include anorexia, vomiting, diarrhea, jaundice, malaise, and myalgia

Antiviral Non-HIV Drugs

Used to prevent or delay the spread of viral infections.
Classifications include: (non-classified, topical, neuraminidase inhibitors, gamma globulin, purine nucleoside).
Examples: Amantadine HCl (influenza A), Cidofovir (CMV retinitis), Foscarnet (herpes viruses), Rimantadine HCL (influenza), Telbivudine, Adefovirdipivoxil, Entecavir (chronic hepatitis B virus).
Treat herpes simplex viruses (Idoruxidine, Penciclovir, Trifluridine)

Neuraminidase Inhibitors

Decreases the release of viruses from infected cells, reducing viral spread and shortening flu symptom duration.
They inhibit the activity of neuraminidase, a viral glycoprotein, effective against influenza A and B viruses. Examples include Zanamivir and Oseltamivir Phosphate.

Gamma Globulin (Immune Globulin)

Provides passive immunity to viruses by blocking their penetration into host cells.
Administered during the initial stages of illness, preventing further viral invasion.

Purine Nucleoside

Interfere with steps of viral nucleic acid synthesis.
Effective against herpes simplex viruses, herpes zoster, CMV. Examples are Ribavirin, Acyclovir, Famciclovir.

HIV-AIDS

HIV is an RNA retrovirus needing a living human cell to survive and replicate
Destroys helper T cells (CD4+ T lymphocytes), leading to immune deficiency.
CD4 cell count is a measure of immune function; normal ranges from 800-1200 cells/mm³.
Reduced CD4 cell count leads to high viral loads in peripheral blood and opportunistic infections, ultimately developing to AIDS (with a CD4 count below 200 cells/mm³)
HIV is spread through intimate contact with blood, semen, vaginal fluids, and breast milk; sexual contact (oral, vaginal, and anal), direct blood contact (IV drug use, contaminated items), mother-to-child transmission.
Symptoms include fever, fatigue, pharyngitis, myalgia, arthralgia, lymphadenopathy, headache, and night sweats (initially may be mistaken for the flu)

Antiretroviral Agents

The standard of care for HIV infection
Combinations (e.g., EFAVIRENZ/TENOFOVIR/EMTRICITABINE, RITONAVIR-BOOSTED ATAZANAVIR/TENOFOVIR/EMTRICITABINE): preferred for maintaining, sustaining, and maintaining sustained suppression

NRTIs

Foundation of ART, acting by interfering with viral RNA-dependent DNA polymerase replication.
Examples include Zidovudine, Didanosine, Stavudine, Lamivudine, Abacavir, Tenofovir, Emtricitabine
Dosage adjustments may be needed in patients with renal insufficiency (creatinine clearance less than 50 mL/min)

NNRTIs

Prevent viral replication by competing with binding to reverse transcriptase
Examples include Efavirenz, Delavirdine, Nevirapine, Rilpivirine

Protease Inhibitors

Act at the end of the HIV life cycle, inhibiting the HIV protease, an enzyme essential for viral assembly and release
Examples include Lopinavir/ritonavir, Atazanavir, Fosamprenavir, Tipranavir, Darunavir, Saquinavir, Indinavir

Entry Inhibitors

Prevent HIV cell entry by inhibiting fusion of HIV and CD4 cells.
Enfuvirtide is an example

CCR5 Co-Receptor Antagonists

Blocks the CCR5 co-receptor that HIV needs to enter immune cells, preventing replication. Example is Maraviroc

Integrase Inhibitors

Interferes with integrase, the enzyme HIV needs to multiply, effectively limiting viral replication.
Examples include Raltegravir, Dolutegravir

Nursing Role

Thorough assessment of patients' physiological and psychosocial health, and literacy levels
Educate patients about medication adherence strategies.
Counsel about hand hygiene and other preventive methods to reduce infection risk.
Monitor laboratory test results (CD4, viral load), and informing appropriate healthcare providers as needed.
Monitor for side effects.
Coordinate patient care with other healthcare providers.

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Description

Test your knowledge on key characteristics of viruses, modes of transmission, and antiviral treatments. This quiz covers important topics about influenza and herpes simplex viruses, including symptoms, transmission routes, and treatment options.