A nurse assesses an audible grating sound (crepitus) when a client with osteoarthritis moves his knees. What is the cause of this sound?

Choice A reason: Properly disposing of contaminated equipment is an important infectioncontrol measure, but it is not the most effective way to prevent the spread of pathogens during client care. Contaminated equipment, such as gloves, gowns, masks, or needles, should be disposed of in designated containers or bags to prevent exposure or injury to others. However, this measure does not eliminate the risk of transmission of pathogens from the hands of the health care worker to the client or the environment.

Choice B reason: Discarding used syringes into appropriate containers is an important infectioncontrol measure, but it is not the most effective way to prevent the spread of pathogens during client care. Used syringes, especially those that contain blood or body fluids, should be discarded into punctureresistant, leakproof, and labeled containers to prevent needlestick injuries or exposure to others. However, this measure does not eliminate the risk of transmission of pathogens from the hands of the health care worker to the client or the environment.

Choice C reason: Changing soiled linens is an important infectioncontrol measure, but it is not the most effective way to prevent the spread of pathogens during client care. Soiled linens, especially those that contain blood or body fluids, should be changed and handled with gloves and minimal agitation to prevent contamination or aerosolization of pathogens. However, this measure does not eliminate the risk of transmission of pathogens from the hands of the health care worker to the client or the environment.

Choice D reason: Performing hand hygiene is the most effective way to prevent the spread of pathogens during client care, because it reduces the number of microorganisms on the hands of the health care worker, which are the most common source and mode of transmission of infection. Hand hygiene should be performed before and after contact with the client, after contact with potentially infectious materials, after removing gloves, and before and after performing invasive procedures. Hand hygiene can be performed by washing with soap and water or using alcoholbased hand rubs.

Choice A reason: A susceptible host is not an infectious disease, but a factor that influences the transmission of an infectious disease. A susceptible host is a person who is vulnerable to infection due to factors such as age, health status, immunization, or genetic predisposition. A susceptible host may become infected by a communicable disease, but it is not the disease itself.

Choice B reason: A communicable disease is an infectious disease that can be transmitted directly from one person to another. A communicable disease is caused by a pathogen, such as a virus, bacterium, fungus, or parasite, that can spread through contact, droplet, airborne, vector, or vehicle transmission. Examples of communicable diseases are influenza, tuberculosis, measles, malaria, and HIV/AIDS.

Choice C reason: A portal of entry to a host is not an infectious disease, but a factor that influences the transmission of an infectious disease. A portal of entry to a host is a route through which a pathogen can enter the body of a susceptible host and cause infection. A portal of entry to a host may be a break in the skin, a mucous membrane, or a body opening, such as the mouth, nose, eyes, or genitals. A portal of entry to a host may facilitate the transmission of a communicable disease, but it is not the disease itself.

Choice D reason: A portal of exit from the reservoir is not an infectious disease, but a factor that influences the transmission of an infectious disease. A portal of exit from the reservoir is a route through which a pathogen can leave the body of an infected person or animal and reach another susceptible host. A portal of exit from the reservoir may be a body fluid, such as blood, saliva, urine, or feces, or a body part, such as the skin, hair, or nails. A portal of exit from the reservoir may enable the transmission of a communicable disease, but it is not the disease itself.