MCQs on Human Immunodeficiency Virus (HIV/ AIDS) with answers: Medical Microbiology

Multiple Choice Questions on Human Immunodeficiency Virus (HIV/AIDS) with answers

1) Which virus is associated with acquired immune deficiency syndrome (AIDS) pandemic?

A) HIV-2

B) HTLV-1

C) HIV-1

D) HIV-3

2) Which of the following is an important molecule present in the outer membrane of HIV that helps the virus to enter and infect host cells?
a) Polysaccharides
b) Glycoproteins
c) Proteins
d) Lipopolysaccharides

3) Select all the incorrect options given below for the common route of transmission of HIV from one person to another?
a) Unprotected sexual contact with an infected person
b) From infected mother to the fetus
c) From the mosquito bite 
d) Exposure to contaminated blood and blood products

e) Using and sharing the same swimming pool 

4) HIV belongs to which of the following genus member of the virus?
a) Orthomyxovirus
b) Retrovirus
c) Parvovirus
d) Reovirus

5) All of the following statements regarding HIV infection in human is true, EXCEPT?
a) Person once infected will remain infected for life if untreated
b) Monocytes and macrophages are the major reservoirs of the virus
c) HIV infection progresses mainly in 3 stages with AIDS being the most severe stage
d) The possible flu like symptoms fever, chills, fatigue, and sore throat after an initial exposure

e) Medicines are available for the complete cure of the late (severe) stage of the HIV infections

6) Which of the following enzyme is required for the viral replication process and plays a critical role in the pathogenesis of HIV infection?
a) RNA polymerase
b) DNA polymerase
c) RNA polymerase II
d) Reverse transcriptase

7) The envelope protein gp120 (Glycoprotein 120) is required for the attachment of the HIV virus to CD4 receptors of target host cells. 

Identify the immune cells that consist of CD4 receptors:
a) T helper cells
b) Monocytes
c) Macrophages
d) Dendritic cells

8) Choose the correct answer: The chemokine receptor cell present in the host macrophages that helps in the primary attachment of HIV is............................
a) CxCR 4
b) CCR5
c) Both of the above
d) None of the above

9) Which of the following is an important HIV antigen in determining the used as diagnostic marker for the early detection and diagnosis of HIV infection?
a) p24
b) gp120
c) Pol gene
d) Gp120

10)Which of the following bacterial infections is predominant in chronic HIV-infected patients or in AIDS?
a) Pneumocystis carinii pneumonia
b) Tuberculosis
c) Candidiasis
d) Toxoplasmosis

11) When was the first case of human AIDS reported in the USA?
a) 1990
b) 1982
c) 1981
d) 1991

12) Which of the following protease inhibitor drug is used as a Highly active antiretroviral therapy (HAART), in a combination regimen with other antiretroviral drugs.

a) Efavirenz
b) Indinavir
c) Ritonavir
d) Zidovudine

13) All of the following are examples of clinically important specimens that can be taken from a HIV infected patient for the laboratory diagnosis of HIV infection, EXCEPT?
a) Blood
b) Saliva with the presence of blood
c) Genital secretions
d) Urine with no presence of blood

14) Which of the following drug have shown significant results in reducing the transmission of HIV infection from a pregnant mother to a baby?
a) Acyclovir
b) Zidovudine
c) Ceftriaxone
d) None of the above

15) All of the following are the effective current preventive methods for HIV infection?

Select all the correct answers:
a) Practice safe and protected sex
b) Taking pre-exposure prophylaxis (PrEP) medications for individuals at higher risk of HIV

c) Use of clean (sterile) injection needles for drug use
d) Safe blood transfusion method

 

16) It is estimated that millions of people live with HIV positive since the disease first occurred in humans.  

Which of the following country is mostly affected by the HIV/AIDS epidemic?

a) Bangladesh 

b) India

c) South Africa

d) United States

17) A 45 year old man is diagnosed with AIDS, he was first tested positive for HIV 5 years earlier. 

Which of the following statements is true regarding the diagnosis of the disease?

a) A low CD4+ T cell count (>200 cells/mm3)

b) It occurs at the early stage of the HIV infection

c) The person with AIDS can live up to 10 years

d) The virus is usually in a dormant state during this stage

18) Prenatal HIV testing is one of the crucial blood tests recommended during the pregnancy that aims to minimize and prevent the transmission of the infection from mother to the newborn. 

According to data published by UNICEF which of the following continent have an increasing number of babies diagnosed with HIV positive from the year 2010 to 2020?

a) Africa

b) Australia

c) Europe

d) North America

19) Name the possible source of the transmission of HIV in humans that is believed to have first occurred in Africa 

a) A duck

b) A pig

c) A cow

d) A chimpanzee

20) Select all the opportunistic infections which are common in the HIV/AIDS infection.

a) Candidiasis

b) Meningitis 

c) Pneumocystis pneumonia (PCP)

d) Tuberculosis (TB)

21. All of the following laboratory diagnosis is tested positive for early stage HIV infection, EXCEPT?

a) Blood test with CD4+ T-cell count of 350 cells/mm³ (normal range: 500-1600 cells/mm³)

b) Complete Blood count with chronic anemia

c) Confirmatory Western blot test positive for HIV-1 antibodies

d) Positive HIV enzyme immunoassay (EIA) test

22) A 32 year old woman visited a local health clinic with complaints of persistent fatigue, unexplained weight loss of about 15 pounds, recurrent fevers, over the past five months. She has no significant medical history, allergies, or prior hospitalizations.

Upon examination, the patient appears visibly fatigued, she mentions experiencing night sweats and intermittent low-grade fevers. She reports a persistent dry cough and intermittent shortness of breath, especially during physical exertion.

Her physical examination reveals oral candidiasis (white patches on the oral mucosa), and she has multiple skin lesions consistent with Kaposi's sarcoma. HIV infection is suspected.

Which of the following test is the screening test usually done for the HIV diagnosis?

a) Enzyme immunoassay (EIA) test

b) PCR or viral load test

c) Venereal disease research laboratory (VDRL) test

d) Western blot test

23. Which type of testing is used to assess the reaction of HIV-1 isolates to nucleoside analog reverse transcription (RT) inhibitors?

a) Genotypic susceptibility testing

b) Recombinant virus assay (RVA)

c) Blood culture

d) ELISA

24. Which personal protective equipment should be worn when handling specimens capable of harboring bloodborne agents in the laboratory?

a. Boots and a helmet

b. Face mask and goggles

c. Laboratory gown, good-quality gloves, and eye protection

d. Lab coat and apron

Multiple Choice Answers with Explanation:

1- C) HIV-1
2- b) Glycoproteins. gp120 (Glycoprotein 120) and gp41 (Glycoprotein 41) are the two main glycoproteins found on the HIV envelope, these proteins play a crucial role in host cell infection by the virus.

3- c) From the mosquito bite, (e) Using and sharing the same swimming pool. 

HIV is primarily transmitted through the exchange of certain body fluids, such as blood, semen, vaginal fluids, rectal fluids, and breast milk.

4- b) Retrovirus
5- d) Medicines are available for the complete cure of the chronic stage of the HIV infections

6- d) Reverse transcriptase. An enzyme that plays a central role in the replication of the virus, it is responsible for the conversion of viral RNA into DNA, which can then be integrated into the host cell's genome.

7- a) T helper cells. A type of white blood cell that are the primary target of the HIV. The virus infects and destroys CD4+ T cells, leading to a progressive weakening of the immune system and the development of acquired immunodeficiency syndrome (AIDS) if left untreated.  

8- b) CCR5. It is a chemokine receptor, a member of the G protein-coupled receptor (GPCR) family.  It plays an important role as a co-receptor for HIV entry into host cells. 

9- a) p24. p24 is a structural protein found in the core of the HIV virus. The p24 detection in blood or serum of patient is used as a diagnostic marker and also for the early diagnosis of HIV infection. 

10- b) Tuberculosis. Individuals infected with HIV are particularly susceptible to developing active tuberculosis, HIV-associated tuberculosis remains a significant challenge to world health, with millions of individuals living with HIV-associated tuberculosis.

11- c) 1981

12- b) Indinavir, it specifically inhibits the action of the HIV protease enzyme, which is essential for the replication of the virus.

13- d) Urine with no presence of blood

14- b) Zidovudine. It is a Nucleoside/Nucleotide Reverse Transcriptase Inhibitors (NRTIs), commonly used as part of a backbone regimen in combination with other classes of drugs. The drug inhibits the reverse transcriptase enzyme, preventing the virus from replicating its genetic material. 

15- a), b), c), and d)

16- c) South Africa. HIV infection remains a significant public health challenge in Africa. The factors includes limited access to healthcare and antiretroviral therapy (ART) in some areas, high levels of poverty, gender inequality, and sexual violence and limited access to education and prevention programs.

17- a)A low CD4+ T cell count (>200 cells/mm3). Monitoring the number of CD4+ T cells (normal range is 500-1600 cells/mm³) in the blood is an important measure in individuals with HIV/AIDS, as a decrease in CD4+ T cell count indicates a weakened immune system.

18-a) Africa. It is affected by HIV/AIDS epidemic, with a high prevalence of HIV infections compared to other regions of the world.

19-d) A chimpanzee

20-a, b, c, and d. One of the defining characteristics of AIDS is the increased susceptibility to opportunistic infections. Various bacterial, viral and fungal infections can be severe or life-threatening in individuals with AIDS.  

21- b) Complete Blood count with chronic anemia. Usually mild anemia is observed in early stage HIV infection.

22- a) Enzyme immunoassay (EIA) test. It is an antibody-based test (EIA). If the result is positive or inconclusive, further testing is done.

23. b) Recombinant virus assay (RVA). The recombinant virus assay (RVA) is a laboratory test used to assess the susceptibility of HIV-1 isolates to specific antiretroviral drugs, particularly nucleoside analog reverse transcription (RT) inhibitors. The primary purpose of the RVA is to determine how effective certain antiretroviral drugs are against the patient's HIV virus. It helps in selecting the most appropriate antiretroviral treatment regimen based on the drug's effectiveness against the specific virus strain.

24. c) Laboratory gown, good-quality gloves, and eye protection