Health care-associated infection: Nursing

A health care-associated infection, or HAI, is when a pathogen is transmitted to a patient who’s been hospitalized for at least 48 hours.    As the nurse, you can prevent health care-associated infections by breaking the chain of infection.  

The process of transmitting infection is known as the chain of infection and occurs in six continuous links: the causative agent, reservoir, portal of exit, mode of transfer, portal of entry and susceptible host.  

The first link is the presence of a causative agent, or pathogen, which is any disease-causing microorganism, like viruses, bacteria, yeast, fungi, or protozoa. Examples of common pathogens include the bacteria E. coli and the COVID-19 virus.  

The second link is the reservoir, or environment where the pathogen normally lives, multiplies, and grows. Reservoirs can be living, like humans, animals, or insects; waste products, like stool; food; water; or wounds.  

Common reservoirs in health care settings are unwashed hands, soiled linens, or medical equipment, like stethoscopes. 

Now, as the nurse you can reduce pathogens and reservoirs through asepsis, which is when pathogens are removed from the environment. There are two types of asepsis: medical asepsis and surgical asepsis. Medical asepsis, also known as clean technique, is when the number of pathogens or the risk of transmitting the pathogen, is reduced. This can be done through hand washing, wiping down equipment with a disinfectant, and preoperative skin cleansing. On the other hand, surgical asepsis, also known as sterile technique, is when equipment is sterilized eliminating all pathogens by using high heat or chemicals like when using surgical equipment that has been sterilized in an autoclave. 

Then, there’s the third link, portal of exit, where the pathogen leaves the reservoir. Common portals of exit in health care settings include the GI tract, where pathogens exit via feces or emesis; and the respiratory tract, where pathogens leave via aerosolized droplets.  

You’ll use standard and transmission-based precautions to prevent pathogens from reaching a portal of exit. Standard precautions are broad protocols used to prevent infection in both the patient and nurse. Standard precautions are used with every patient, regardless of the presence of infection, and involve hand hygiene; use of personal protective equipment, or PPE, like gloves; and covering the mouth while coughing or sneezing.  

On the other hand, transmission-based precautions are used alongside standard precautions; include contact, droplet, and airborne precautions; and are based on a known pathogen’s mode of transfer, which is the fourth link in the chain.