CHAIN OF INFECTION MIDTERM

Question 1

A nurse forgets to disinfect a surgical tool before an operation. What part of the chain of infection is compromised?

Answer 1

Pathogen – The unsterilized tool may introduce infectious microorganisms.

Question 2

A patient with tuberculosis does not take their full course of antibiotics. What might happen?

Answer 2

The pathogen may not be fully eliminated, leading to drug resistance and ongoing infection.

Question 3

A hospital fails to use proper chemical disinfectants for cleaning. What could be the consequence?

Answer 3

Pathogens may survive on surfaces, increasing the risk of healthcare-associated infections.

Question 4

A person carrying Salmonella does not show symptoms but spreads the bacteria. What kind of carrier are they?

Answer 4

Asymptomatic carrier – They can transmit the pathogen without showing illness.

Question 5

A community lacks proper waste management, leading to rodent infestations. How does this contribute to infection?

Answer 5

Rodents can act as reservoirs for diseases like leptospirosis.

Question 6

A hospital does not properly dispose of used syringes. What risk does this pose?

Answer 6

The syringes can become a reservoir for bloodborne infections like HIV and hepatitis B.

Question 7

A patient with the flu sneezes without covering their mouth. How does this contribute to disease spread?

Answer 7

The respiratory droplets act as a portal of exit, allowing airborne transmission.

Question 8

A person with an open wound does not cover it. How does this affect infection control?

Answer 8

The wound serves as a portal of exit, releasing infectious agents into the environment.

Question 9

A healthcare worker improperly disposes of a patient’s blood sample. What could happen?

Answer 9

The blood may serve as a portal of exit, spreading bloodborne pathogens.

Question 10

A person touches a contaminated doorknob and later rubs their eyes. What type of transmission is this?

Answer 10

Indirect contact transmission – The contaminated surface acted as a vehicle.

Question 11

A mosquito bites an infected person and then bites another person. What mode of transmission is this?

Answer 11

Vectorborne transmission – The mosquito acts as a biological vector.

Question 12

A person drinks untreated water containing Vibrio cholerae. What mode of transmission is involved?

Answer 12

Vehicleborne transmission – The pathogen was transmitted through contaminated water.

Question 13

A nurse moves between patients without washing hands. What risk does this pose?

Answer 13

The nurse may spread infections through direct contact transmission.

Question 14

A sick individual coughs near others without wearing a mask. How is the infection transmitted?

Answer 14

Droplet transmission – The respiratory droplets carry the infectious agent.

Question 15

A patient receives an injection with an unsterile needle. What portal of entry is affected?

Answer 15

The bloodstream – The contaminated needle introduces the pathogen directly.

Question 16

A person eats food contaminated with bacteria. What portal of entry is involved?

Answer 16

The gastrointestinal tract – The bacteria enter through ingestion.

Question 17

A healthcare worker accidentally touches their face after handling infected material. What portal of entry is used?

Answer 17

The mucous membranes (eyes, nose, mouth) – The pathogen enters through these sites.

Question 18

A person with a deep cut steps into dirty water. What portal of entry is involved?

Answer 18

The skin – The cut provides direct access for pathogens.

Question 19

A child with no prior exposure to chickenpox interacts with an infected person. What makes them susceptible?

Answer 19

They lack immunity, making them a susceptible host.

Question 20

An elderly patient contracts pneumonia after a hospital stay. Why are they at higher risk?

Answer 20

Age-related immune decline makes them more susceptible.

Question 21

A cancer patient undergoing chemotherapy develops an infection. Why?

Answer 21

Chemotherapy weakens the immune system, increasing susceptibility.

Question 22

A person with diabetes gets a foot infection. Why are they at risk?

Answer 22

Diabetes impairs circulation and immune response, increasing infection risk.

Question 23

A malnourished child is frequently sick. What factor makes them susceptible?

Answer 23

Poor nutrition weakens the immune system, making infections more likely.

Question 24

A person with HIV is advised to get vaccinated for pneumonia. Why?

Answer 24

HIV weakens the immune system, making them more vulnerable to infections.

Question 25

A person is exposed to the flu but has no symptoms for a few days. What stage of infection is this?

Answer 25

Incubation period – The virus is multiplying but has not yet caused symptoms.

Question 26

A patient feels fatigued and slightly feverish before developing full-blown measles. What stage is this?

Answer 26

Prodromal stage – Early, nonspecific symptoms appear.

Question 27

A person with COVID-19 experiences severe difficulty breathing. What stage is this?

Answer 27

Illness stage – The disease reaches its peak.

Question 28

A person with food poisoning starts feeling better after taking medication. What stage is this?

Answer 28

Decline stage – The body is overcoming the infection.

Question 29

A person recovering from chickenpox still feels weak but no longer has active symptoms. What stage is this?

Answer 29

Convalescence stage – The body is healing after infection.

Question 30

A hospital implements mandatory hand hygiene policies. What link does this target?

Answer 30

Mode of transmission – It prevents the spread of pathogens via contact.

Question 31

A patient with tuberculosis is placed in an isolation room. What link is being broken?

Answer 31

Mode of transmission – Isolation prevents airborne spread.

Question 32

A nurse administers a flu vaccine to a patient. What link is targeted?

Answer 32

Susceptible host – Vaccination strengthens immunity.

Question 33

A doctor prescribes antibiotics to a patient with bacterial pneumonia. What link does this break?

Answer 33

Pathogen – The antibiotics eliminate the bacteria.

Question 34

A restaurant ensures all food is cooked to the proper temperature. What link is being addressed?

Answer 34

Pathogen – Proper cooking kills harmful microorganisms.

Question 35

A hospital uses HEPA filters in rooms for immunocompromised patients. What link is targeted?

Answer 35

Mode of transmission – HEPA filters reduce airborne pathogen spread.

Question 36

A community installs clean water systems. What link is broken?

Answer 36

Reservoir – Clean water reduces waterborne infections.

Question 37

A nurse wears gloves while handling a patient's wound. What link is addressed?

Answer 37

Portal of entry – Gloves prevent pathogen entry.

Question 38

A daycare enforces routine toy sanitation. What link is being broken?

Answer 38

Mode of transmission – Cleaning reduces indirect contact transmission.

Question 39

A traveler takes malaria prophylaxis before visiting a high-risk area. What link is targeted?

Answer 39

Susceptible host – Preventative medication reduces risk.

Question 40

A hospital properly disposes of used needles in a sharps container. What link does this break?

Answer 40

Portal of exit – Proper disposal prevents exposure to infected blood.

Question 41

A community receives COVID-19 booster shots. What link is disrupted?

Answer 41

Susceptible host – Boosters enhance immunity.

Question 42

A hospital implements routine screening for MRSA carriers. What link does this break?

Answer 42

Reservoir – Identifying carriers helps prevent transmission.

Question 43

A factory provides PPE for workers exposed to hazardous materials. What link is targeted?

Answer 43

Portal of entry – PPE blocks pathogen entry.

Question 44

A patient diagnosed with measles stays home. What link is affected?

Answer 44

Mode of transmission – Isolation prevents spread.

Question 45

A daycare enforces handwashing before meals. What link is broken?

Answer 45

Mode of transmission – Proper hygiene prevents spread.

Question 47

A laboratory technician forgets to sterilize petri dishes before reusing them. What could happen?

Answer 47

Contamination could occur, leading to the growth of infectious pathogens.

Question 48

A patient contracts a bacterial infection that is resistant to multiple antibiotics. What is this called?

Answer 48

Multidrug-resistant infection – The pathogen has developed resistance to standard treatments.

Question 49

A scientist develops a new antiviral drug. What link in the chain of infection does this target?

Answer 49

Pathogen – The drug inhibits the virus from replicating and causing disease.

Question 50

A hospital fails to separate patients with a highly contagious disease. What risk does this pose?

Answer 50

The pathogen can spread easily to other patients and staff.

Question 51

A person with untreated tuberculosis continues working in a crowded office. What might happen?

Answer 51

The infection may spread through airborne transmission.

Question 52

A group of wild animals in a forest carries a strain of rabies. What role do they play in the chain of infection?

Answer 52

They act as a reservoir for the rabies virus.

Question 53

A hospital detects Legionella bacteria in its water supply. Why is this a concern?

Answer 53

The water acts as a reservoir for the bacteria, which can cause Legionnaires’ disease.

Question 54

A farmer fails to vaccinate livestock against anthrax. What risk does this pose?

Answer 54

The livestock can become reservoirs for anthrax, increasing transmission risk to humans.

Question 55

A person with hepatitis B does not know they are infected and donates blood. What is the risk?

Answer 55

They may unknowingly transmit the virus, as they are acting as a reservoir.

Question 56

An abandoned building contains standing water and mosquitoes. What infectious disease risk does this pose?

Answer 56

The standing water serves as a reservoir for mosquito-borne diseases like dengue and malaria.

Question 57

A patient with an infected wound does not cover it properly. How can this contribute to infection spread?

Answer 57

The open wound serves as a portal of exit, releasing pathogens into the environment.

Question 58

A nurse treats a patient with Ebola but does not properly dispose of contaminated gloves. What might happen?

Answer 58

The gloves may act as a portal of exit, carrying the virus to another host.

Question 59

A person with a respiratory infection talks loudly near others. How does this affect transmission?

Answer 59

Droplets expelled while speaking can serve as a portal of exit, spreading the infection.

Question 60

A wastewater treatment facility fails to properly handle human waste. What risk does this create?

Answer 60

Pathogens from fecal matter may spread, increasing the risk of waterborne diseases.

Question 61

A blood sample from an HIV-positive patient spills in a lab. Why is this a concern?

Answer 61

Blood acts as a portal of exit for HIV, increasing the risk of accidental exposure.

Question 62

A person with a cold shakes hands with someone else without washing their hands. What mode of transmission is this?

Answer 62

Direct contact transmission – The virus spreads through skin-to-skin contact.

Question 63

A food worker does not wash their hands after using the restroom and then handles food. What mode of transmission is this?

Answer 63

Fecal-oral transmission – Pathogens from unwashed hands can contaminate food.

Question 64

A cat scratches a person, leading to an infection. What type of transmission is involved?

Answer 64

Direct transmission – The bacteria from the cat's claws enter the wound.

Question 65

A sick person drinks from a shared water bottle. What type of transmission is this?

Answer 65

Indirect transmission – The water bottle acts as a vehicle for the pathogen.

Question 66

A family lives in a house infested with fleas. What type of disease transmission might occur?

Answer 66

Vectorborne transmission – Fleas can spread diseases like typhus or plague.

Question 67

A healthcare worker forgets to wear a mask while treating a patient with tuberculosis. What portal of entry is involved?

Answer 67

The respiratory tract – The worker may inhale the airborne bacteria.

Question 68

A child playing outside gets a cut on their foot and later develops an infection. What portal of entry is affected?

Answer 68

The skin – The cut provides an entry point for bacteria.

Question 69

A person rubs their eyes after touching a contaminated doorknob. What portal of entry is involved?

Answer 69

The mucous membranes – The eyes serve as an entry point for infection.

Question 70

A tourist eats undercooked seafood and contracts food poisoning. What portal of entry is affected?

Answer 70

The gastrointestinal tract – The contaminated food introduces pathogens into the body.

Question 71

A diabetic patient develops a foot ulcer that becomes infected. What is the portal of entry?

Answer 71

The ulcer provides direct access for pathogens to enter the body.

Question 72

A newborn baby is exposed to the flu but does not have any prior immunity. Why is this concerning?

Answer 72

The baby is a susceptible host due to an underdeveloped immune system.

Question 73

A smoker develops a respiratory infection more easily than a non-smoker. Why?

Answer 73

Smoking damages the lungs, making them more susceptible to infections.

Question 74

A person undergoing an organ transplant takes immunosuppressants. How does this affect their infection risk?

Answer 74

The medications weaken the immune system, increasing susceptibility.

Question 75

An elderly patient is advised to get a pneumonia vaccine. Why?

Answer 75

Older adults are more susceptible to respiratory infections due to weakened immunity.

Question 76

A malnourished person frequently gets sick. What makes them vulnerable?

Answer 76

Poor nutrition weakens the immune system, increasing susceptibility.

Question 77

A person with the flu stays home instead of going to work. What link in the chain of infection is disrupted?

Answer 77

Mode of transmission – Avoiding contact reduces the spread of the virus.

Question 78

A healthcare worker wears gloves while treating an open wound. What link is being broken?

Answer 78

Portal of entry – Gloves prevent direct pathogen entry into the body.

Question 79

A hospital disinfects all surfaces daily. What link in the chain of infection does this target?

Answer 79

Pathogen and mode of transmission – Disinfection eliminates microbes on surfaces.

Question 80

A person takes anti-malaria medication before traveling to an endemic area. What link is disrupted?

Answer 80

Susceptible host – Preventive medication strengthens protection against infection.

Question 81

A doctor prescribes antiviral drugs for a flu patient. What link is being broken?

Answer 81

Pathogen – The medication helps reduce viral replication.

Question 82

A community promotes vaccination campaigns against measles. What link is disrupted?

Answer 82

Susceptible host – Immunization prevents people from getting infected.

Question 83

A patient with hepatitis B is advised not to share razors or toothbrushes. What link is being targeted?

Answer 83

Mode of transmission – Avoiding shared items prevents indirect contact transmission.

Question 84

A nurse wears a face shield while treating a COVID-19 patient. What link does this break?

Answer 84

Portal of entry – The shield blocks respiratory droplet exposure.

Question 85

A hospital isolates patients with airborne infections. What link is being broken?

Answer 85

Mode of transmission – Isolation prevents airborne spread.