Infection Control — Certified Nursing Assistant Practice Test

This Certified Nursing Assistant Infection Control practice set has 70 practice questions based on the official exam materials, each with an instant explanation.

Sample questions

Three questions from the Infection Control bank with the correct answer and an explanation. The practice quiz above draws 30 questions at random from the same bank.

1. The chain of infection has six links. Which sequence correctly lists them?

   • Pathogen, reservoir, portal of exit, mode of transmission, portal of entry, susceptible host — Correct answer
   • Susceptible host, portal of entry, pathogen, reservoir, portal of exit, transmission
   • Reservoir, pathogen, susceptible host, portal of entry, transmission, portal of exit
   • Mode of transmission, portal of exit, reservoir, pathogen, susceptible host, portal of entry

   Explanation: The chain of infection (感染链/cadena de infección) is: pathogen → reservoir → portal of exit → mode of transmission → portal of entry → susceptible host. Knowing the chain helps the aide find where to break it. (Source: Basic Nursing Skills — Infection Control; CDC)

   Handbook: Basic Nursing Skills — Infection Control

2. How does stopping the spread of infection relate to the chain of infection?

   • Breaking any one link in the chain stops the infection from spreading — Correct answer
   • All six links must be broken at the same time to stop spread
   • The chain cannot be broken once an outbreak begins
   • Only a doctor can break a link in the chain

   Explanation: Breaking any single link in the chain of infection (感染链/cadena de infección) stops the infection from spreading. The aide does not need to break every link — interrupting just one is enough. (Source: Basic Nursing Skills — Infection Control; CDC)

   Handbook: Basic Nursing Skills — Infection Control

3. Which link in the chain of infection does the nurse aide most often break with good hand hygiene?

   • The mode of transmission — Correct answer
   • The susceptible host
   • The pathogen itself
   • The reservoir

   Explanation: Hand hygiene (手卫生/higiene de manos) breaks the mode of transmission — the hands carry pathogens from one person or surface to another, so clean hands interrupt that link. (Source: Basic Nursing Skills — Infection Control; CDC)

   Handbook: Basic Nursing Skills — Infection Control