Question 1

Gonorrhea is an STD caused by which type of organism?

Accepted Answer

Answer reason: Gonorrhea is caused by the bacterium Neisseria gonorrhoeae, a Gram-negative diplococcus.

Question 2

Which of the following conditions is often seen in patients with gonorrhea?

Accepted Answer

Answer reason: Chlamydia commonly co-infects with Neisseria gonorrhoeae; co-testing and co-treatment are standard. Trachoma is ocular chlamydial disease, and herpes/syphilis are different STIs not specifically associated as frequent co-infections with gonorrhea.

Question 3

What is this disease called?

Accepted Answer

Answer reason: Among the options, measles is the communicable disease name; 'jundice' is a symptom, and 'maleria' and 'tetanus' are different conditions.

Question 4

Ringworm infects which part of the body?

Accepted Answer

Answer reason: Ringworm (tinea) is a dermatophyte fungal infection that involves keratinized tissues, primarily the skin.

Question 5

What is the most common cause of pneumonia?

Accepted Answer

Answer reason: Streptococcus pneumoniae (pneumococcus) is the most common cause of community-acquired pneumonia in adults.

Question 6

Which of the following is a viral disease?

Accepted Answer

Answer reason: AIDS is caused by the human immunodeficiency virus (HIV). Malaria is protozoal, tuberculosis is bacterial (Mycobacterium tuberculosis), and typhoid is bacterial (Salmonella typhi).

Question 7

What is the mode of transmission of leprosy?

Accepted Answer

Answer reason: Leprosy (Mycobacterium leprae) is primarily transmitted via prolonged close contact through nasal/oral respiratory droplets, not by insects or breast milk.

Question 8

What is the chain of spread of malaria?

Accepted Answer

Answer reason: Human malaria is transmitted by the Anopheles mosquito (an arthropod) from human to human; thus the chain is man → arthropod → man. Other animal hosts listed are not part of human malaria transmission.

Question 9

What is the first step in the control of communicable disease?

Accepted Answer

Answer reason: Reporting suspected or confirmed cases initiates surveillance and enables prompt control measures; thus notification is the first step.

Question 10

What are spherical bacteria occurring in clusters called?

Accepted Answer

Answer reason: Staphylococci are spherical bacteria arranged in grape-like clusters; streptococci form chains, coccobacilli are short rods, and 'pneumo' denotes a genus/site not a cluster arrangement.

Question 11

Which of the following infections of animals can primarily be transmitted through milk?

Accepted Answer

Answer reason: Mycobacterium bovis from infected cattle is transmitted to humans via unpasteurized milk. Dengue is mosquito-borne, plague is flea/rodent-borne, and leptospirosis is usually via water contaminated with urine.

Question 12

Which substance destroys or inhibits the growth of microorganisms?

Accepted Answer

Answer reason: Antiseptics are agents applied to living tissue that inhibit the growth of or destroy microorganisms; disinfectants act on objects, and bactericidal refers specifically to killing bacteria.

Question 13

What is the mode of transmission of hepatitis A?

Accepted Answer

Answer reason: Hepatitis A is transmitted via the fecal–oral route, commonly through ingestion of contaminated food or water; it is not spread by blood transfusion or vectors like mosquitoes.

Question 14

What is the diagnostic test used for scarlet fever?

Accepted Answer

Answer reason: The Dick test assesses susceptibility to the erythrogenic toxin of Streptococcus pyogenes associated with scarlet fever. Mantoux is for TB, Schick for diphtheria, and Widal for typhoid.

Question 15

What is the term for the constant presence of infection in a given geographical area without any external input?

Accepted Answer

Answer reason: Endemic describes the constant baseline presence of a disease or infectious agent within a specific geographic area without external introduction. Epidemic is a sudden increase, pandemic is worldwide spread, and sporadic is irregular infrequent cases.

Question 16

Widal test is performed for identifying which microorganism?

Accepted Answer

Answer reason: The Widal test detects agglutinating antibodies (O and H) against Salmonella typhi/paratyphi, used in typhoid fever diagnosis.

Question 17

Hepatitis is a what type of disease?

Accepted Answer

Answer reason: Most common forms of hepatitis (A, B, C, D, E) are caused by viruses, so it is classified as a viral disease.

Question 18

What is the causative organism of cat scratch disease?

Accepted Answer

Answer reason: Cat scratch disease is caused by the gram-negative bacillus Bartonella henselae; other options are not the etiologic agent.

Question 19

Sterilization by using ionizing radiations is called as-?

Accepted Answer

Answer reason: Ionizing radiation (gamma rays, electron beams) sterilizes without significant heat, hence termed cold sterilization. Pasteurization and tyndallization are heat methods; 'ionization' is not the standard name of the process.

Question 20

Candidiasis is a-?

Accepted Answer

Answer reason: Candidiasis is caused by Candida species (yeasts), making it a fungal infection.

Question 21

What is the most common cause of meningitis in children aged 6 months to 2 years?

Accepted Answer

Answer reason: Haemophilus influenzae type b historically is the most common bacterial cause of meningitis in children 6 months to 2 years; E. coli is typical in neonates, while pneumococcus and meningococcus predominate in older children/adults.

Question 22

Which stain is used to identify acid-fast bacilli?

Accepted Answer

Answer reason: Acid-fast bacilli (e.g., Mycobacterium) are identified using the Ziehl-Neelsen acid-fast stain; the others are Romanowsky-type blood stains.

Question 23

Which type of hepatitis is commonly associated with pregnancy and high mortality?

Accepted Answer

Answer reason: Hepatitis E infection is notably severe in pregnancy, with high maternal mortality especially in the third trimester; other hepatitis types do not carry this characteristic risk.

Question 24

Which of the following is NOT an example of a house fly borne disease?

Accepted Answer

Answer reason: Houseflies mechanically transmit diarrheal diseases such as diarrhoea, cholera, and gastroenteritis. Trench fever is transmitted by the human body louse (Bartonella quintana), not by houseflies.

Question 25

The registered nurse is conducting an in-service for colleagues on the subject of peptic ulcers. The nurse would be correct in identifying which of the following as a causative factor?

Accepted Answer

Answer reason: Helicobacter pylori infection is the primary infectious cause of peptic ulcer disease; the other organisms are unrelated to peptic ulcers.

Question 26

Which of the following is NOT a sexually transmitted disease?

Accepted Answer

Answer reason: Byssinosis is an occupational lung disease from inhaling cotton dust, not sexually transmitted. The others are sexually transmitted infections.

Question 27

Teichoic acid is present in which type of bacteria?

Accepted Answer

Answer reason: Teichoic acids are structural polymers of Gram-positive bacterial cell walls (including lipoteichoic acid); they are absent in Gram-negative bacteria.

Question 28

Which disease affects the parotid gland?

Accepted Answer

Answer reason: Mumps, a paramyxovirus infection, classically causes parotitis with swelling of the parotid salivary glands. Measles, rubella, and chickenpox do not specifically target the parotid gland.

Question 29

What parasite is identified using a Scotch tape swab?

Accepted Answer

Answer reason: The Scotch tape test collects perianal eggs of Enterobius vermicularis (pinworm), making it the standard identification method.

Question 30

What is the portal of entry for the chickenpox virus?

Accepted Answer

Answer reason: Varicella-zoster virus typically enters via inhalation of airborne droplets, infecting the upper respiratory mucosa; thus the portal of entry is the respiratory tract.

Question 31

What does a positive Schick test indicate?

Accepted Answer

Answer reason: A positive Schick skin test shows a local reaction because neutralizing antitoxin is absent, indicating susceptibility to diphtheria; a negative test indicates immunity.

Question 32

What is the 'Klebs Loeffler bacillus' the name of?

Accepted Answer

Answer reason: Klebs–Loeffler bacillus is the historical name for Corynebacterium diphtheriae.

Question 33

A greenish yellow membrane over the pharynx, larynx, and tonsil is seen in which condition?

Accepted Answer

Answer reason: Diphtheria causes a characteristic thick greenish-gray pseudomembrane over the pharynx, larynx, and tonsils due to Corynebacterium diphtheriae exotoxin.

Question 34

The nurse is caring for a patient with cervical carcinoma most likely caused by which virus?

Accepted Answer

Answer reason: Cervical carcinoma is strongly associated with high-risk HPV types (especially 16 and 18). EBV is linked to nasopharyngeal carcinoma and Burkitt lymphoma; adenovirus and varicella zoster are not typical causes of cervical cancer.

Question 35

Which of the following infectious agents can be transmitted by blood transfusion?

Accepted Answer

Answer reason: Hepatitis viruses (B, C), HIV, and Plasmodium (malaria) are known transfusion-transmitted infections, so all listed agents can be spread via blood transfusion.

Question 36

Which type of tuberculosis (TB) is the most infectious?

Accepted Answer

Answer reason: Pulmonary TB spreads via airborne droplets from the lungs and is the contagious form; extrapulmonary TB (spinal, intestinal, meningeal) is generally not infectious.

Question 37

What test is done to diagnose diphtheria?

Accepted Answer

Answer reason: The Schick test assesses susceptibility to diphtheria toxin and historically was used in diphtheria evaluation. Other options correspond to typhoid (Widal), tuberculosis (Mantoux), and syphilis (VDRL).

Question 38

Which sterilization method is used for culture media?

Accepted Answer

Answer reason: Culture media are routinely sterilized by moist heat in an autoclave (121°C, 15 psi). Dry heat (hot air oven) is for glassware, ethylene oxide and glutaraldehyde are for equipment and instruments, not media.

Question 39

TCBS agar is used to isolate which organism?

Accepted Answer

Answer reason: TCBS (Thiosulfate-Citrate-Bile Salts-Sucrose) agar is selective for Vibrio species, particularly Vibrio cholerae, which produces yellow colonies by sucrose fermentation.

Question 40

From where did the coronavirus get its name?

Accepted Answer

Answer reason: Coronavirus is named for its crown-like spike projections on the virion surface; corona means crown.

Question 41

What is the most common cause of diarrhea in a boy who suddenly develops diarrhea after being treated for fever in the hospital?

Accepted Answer

Answer reason: Hospitalized child treated for fever likely received antibiotics; sudden diarrhea is commonly antibiotic-associated (e.g., C. difficile).

Question 42

What is the media of transmission of bovine type of tuberculosis bacillus?

Accepted Answer

Answer reason: Mycobacterium bovis (bovine TB) is commonly transmitted to humans through ingestion of unpasteurized milk and dairy products.

Question 43

What is Coronavirus?

Accepted Answer

Answer reason: Coronaviruses are a large family of enveloped RNA viruses and are classified within the nidovirus group (order Nidovirales), so both statements A and B are true.

Question 44

Which of the following diseases are related to coronavirus?

Accepted Answer

Answer reason: Both MERS and SARS are caused by coronaviruses (MERS-CoV and SARS-CoV), so both are related to coronavirus.

Question 45

Where was the first novel coronavirus case identified?

Accepted Answer

Answer reason: Early confirmed cases of the 2019 novel coronavirus were first reported in Wuhan, Hubei, China.

Question 46

What type of microorganism causes typhoid?

Accepted Answer

Answer reason: Typhoid fever is caused by Salmonella Typhi, a gram-negative bacterium.

Question 47

What is the term for an epidemic that spreads from country to country or over the whole world?

Accepted Answer

Answer reason: A pandemic is an epidemic that spreads across multiple countries or worldwide. Zoonoses are animal-to-human diseases; sporadic means infrequent, isolated cases; endemic is constant presence in a region.

Question 48

Kala Azar disease is related to which vector?

Accepted Answer

Answer reason: Kala-azar (visceral leishmaniasis) is transmitted by sand flies (Phlebotomus spp.).

Question 49

The agent-host-environment model of health and illness is based on the concept of which option?

Accepted Answer

Answer reason: The agent-host-environment (epidemiologic triad) explains disease occurrence through interactions among an infectious agent, a susceptible host, and the environment—i.e., the concept of infectious disease causation.

Question 50

What term describes the lodgment, development, and reproduction of arthropods on the surface of the body or in clothing?

Accepted Answer

Answer reason: Arthropods such as lice and mites residing and multiplying on the body surface or clothing are ectoparasites, which is termed infestation. Infection implies invasion of tissues by microbes; contamination is mere presence; pollution refers to environmental impurities.

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