Free Virology MCQs with Answers

• A. Capsomere
• B. Capsid
• C. Nucleocapsid
• D. Envelope

Explanation: The capsid is the protein coat surrounding viral nucleic acid. Capsomeres are its individual protein subunits, while a nucleocapsid…

• A. DNA virus
• B. Attacks CD4 cells
• C. Macrophages are the reservoir
• D. Decrease CD4 count in late stages

Explanation: HIV is an RNA retrovirus, not a DNA virus, although it forms a DNA provirus inside host cells.

• A. Carcinoma of nasopharynx
• B. Papilloma
• C. Infectious mononucleosis
• D. Burkitt's lymphoma

Explanation: EBV is associated with infectious mononucleosis, Burkitt lymphoma, and nasopharyngeal carcinoma.

• A. HB Ag
• B. HBs AG
• C. HBV
• D. None of the above

Explanation: The Australian antigen is hepatitis B surface antigen, abbreviated HBsAg.

• A. Virus isolation
• B. Western blot followed by ELISA
• C. ELISA followed by western blot technique
• D. Polymers chain reaction

Explanation: The conventional HIV testing sequence uses ELISA as the screening test, followed by Western blot confirmation of reactive results.

• A. Hepatitis C
• B. Hepatitis D
• C. Hepatitis E
• D. Hepatitis F

Explanation: Hepatitis E is the enterically transmitted non-A, non-B hepatitis virus, usually spread through contaminated food or water.

• A. Antibody of HBs Ag is associated with resistance to infection
• B. Antibody to HBC is not protective
• C. Highest titres of anti HBC are found in persistent carriers of HBs Ag
• D. CMI disappears soon after recover

Explanation: Anti-HBs antibodies are associated with immunity and resistance to HBV infection, whether produced after recovery or vaccination.

• A. Cytopathic changes in culture cells
• B. Presence of viral protein in the infected monolayer
• C. Haemagglutination test
• D. Haemagglutination inhibition test

Explanation: Cytopathic effects, such as cell rounding, fusion, or detachment, are the classic way to detect virus growth in cultured cells.

• A. HBV
• B. IgG anti HAV
• C. Delta Virus
• D. HBC Ag

Explanation: The Dane particle is the complete, infectious hepatitis B virion, consisting of the core and envelope.

• A. Failure to thrive
• B. Have infections
• C. 50% chances to have AIDS
• D. All are true

Explanation: Infants born to mothers with HIV may develop failure to thrive and recurrent infections, but the risk of vertical transmission is…

• A. 24 Hrs
• B. 3-4 days
• C. 2 weeks
• D. 10 daysInfectious Diseases

Explanation: Koplik spots usually appear about 2 to 3 days before the measles rash, commonly described in exam texts as 3 to 4 days.

• A. Cytotropic
• B. Dermatotropic
• C. Chromophilic
• D. Neurotropic

Explanation: Rabies virus has a strong tropism for nervous tissue, travelling through peripheral nerves to the central nervous system, so it is…

• A. Presence of either DNA or RNA
• B. Simple structure
• C. Complex multiplication
• D. All of the above

Explanation: Viruses contain either DNA or RNA, have a relatively simple acellular structure, and multiply by complex replication processes inside…

• A. Hepatitis B virus
• B. Hepatitis C virus
• C. Hepatitis D virus
• D. Hepatitis E virus

Explanation: Hepatitis E virus is mainly transmitted by the faeco-oral route, especially through contaminated water and food.

• A. ELISA
• B. Immunodot
• C. RIPA
• D. Western Blot

Explanation: Western blot was the traditional confirmatory test after a reactive HIV screening ELISA because it identifies antibodies against specific…

• A. Robert koch
• B. Twort and d'herelle
• C. Menkin
• D. Metchinkoff

Explanation: Bacteriophages were independently recognised by Frederick Twort and Félix d’Herelle.

• A. Hepatitis B surface antigen in acute hepatitis
• B. AIDS
• C. Chronic leukemia
• D. Basal cell carcinoma

Explanation: The Australia antigen was later identified as hepatitis B surface antigen, or HBsAg, and is found in acute as well as chronic hepatitis B…

• A. in a week and reach a peak in 3 weeks
• B. only after one year
• C. no antibodies are present in primary HSV
• D. antibodies are present in recurrent and chronic apthous stomatitis

Explanation: HSV antibodies generally begin appearing during the first week of infection and rise to a peak after several weeks.

• A. 24 hours
• B. 6 hours
• C. 12 hours
• D. 3 months

Explanation: Free HIV particles in plasma have a short half-life of roughly 6 hours because they are rapidly cleared or infect target cells.

• A. Chocolate agar
• B. Robertoson's cooked-meat broth
• C. Chorio allantoic membrane
• D. Sabourad's agar

Explanation: Historically, HSV can be cultivated on the chorioallantoic membrane of embryonated eggs, producing characteristic pocks.