Understanding where germs live in healthcare is the first step in understanding how to stop their spread. Germs usually live in places called reservoirs, which are like natural habitats for germs.
Explore the different reservoirs of the human body and the healthcare environment to learn more about where germs are found and how they can spread. Use this information to recognize common infection risks and understand the infection control actions you can take to stop the spread.
Many germs grow on healthy skin.
Germs on skin can get onto surfaces, other people, and things that will touch other people.
Skin – especially hands – carries many germs and spreads them easily.
When someone touches surfaces with their hands, germs can spread from those surfaces to their hands and to others.
Hand hygiene
Appropriate glove use
Safe injections
Cleaning and disinfection
Germs live in dirt and soil. Most of the time they aren't a problem for healthy people but can cause serious illness in people with weakened immune systems.
Building construction can send dirt and the germs in it into the air, which can then get inside a healthcare facility.
Smaller construction and maintenance projects inside a building – like taking out parts of a wall, removing ceiling tiles, or renovating a room – can also create dust that has germs in it.
Cleaning and disinfection
Ventilation
Using barriers and other types of construction containment
Hand hygiene
Viruses like HIV, hepatitis B, and hepatitis C can spread in healthcare when blood from an infected person gets on a sharp item.
If that item causes a cut or break in someone else's skin (e.g., an accidental needlestick), germs can spread to that person and cause a new infection.
Reusing needles or syringes is especially risky because germs in the blood can spread from one person to another.
Outside the body, blood grows bacteria and can spread by touch or devices.
Hand hygiene
Use of personal protective equipment (gloves, gowns, eye protection)
Safe injections
Cleaning and disinfection
Textile management
When a device, like a pulse oximeter, is used on a patient's body to provide care, any germs on that device can be spread to places in or on the patient's body.
When a device is put into a patient's body, like an IV needle, endoscope, or artificial hip, any germs on the device can spread into the body.
If not handled correctly, shared medical devices can spread germs from one patient to another.
Cleaning and disinfection
Device sterilization
Hand hygiene
Use of personal protective equipment (gloves)
Germs found on the body, in the air, and in stool can often be found on dry surfaces, and some can live for a long time.
Dry surfaces include "high-touch" surfaces like bed rails and door handles. They also include things that aren't touched as often, like countertops.
Hands can pick up germs from dry surfaces and move them to other surfaces and people.
Germs from dry surfaces can also get onto devices that are used on or in patients.
Cleaning and disinfection
Device sterilization
Hand hygiene
Use of personal protective equipment (gloves and gowns)
Germs found on the body, in the air, and in stool can often be found on dry surfaces, and some can live for a long time.
Dry surfaces include "high-touch" surfaces like bed rails and door handles. They also include things that aren't touched as often, like countertops.
Hands can pick up germs from dry surfaces and move them to other surfaces and people.
Germs from dry surfaces can also get onto devices that are used on or in patients.
Cleaning and disinfection
Device sterilization
Hand hygiene
Use of personal protective equipment (gloves and gowns)
The gut is filled with bacteria and some yeasts, which are part of a healthy immune system.
Most gut germs don't cause problems in healthy people, but they can cause infection when they spread.
Germs in stool can spread onto hands and skin when wiping or changing a diaper.
Hand hygiene
Use of personal protective equipment (gloves and gowns)
Cleaning and disinfection
Textile management
Waste management
When an infected person talks, breathes, sneezes, or coughs, they produce respiratory droplets that could spread germs.
Germs are more likely to spread in places with poor ventilation or lots of people.
Germs in the nose and mouth can be spread to the skin and hands when people touch their faces, which can then spread to surfaces or other people.
Hand hygiene
Use of personal protective equipment (respirators, eye protection)
Source control (masking)
Cleaning and disinfection
Respiratory hygiene/cough etiquette
Ventilation
Tap water is safe to drink, but it is not sterile. It always has some germs in it.
Most of the time, the germs in tap water aren't a problem for healthy people, but they can cause illness in patients with very weak immune systems.
If medical instruments and equipment (e.g., devices and central lines) get wet, bacteria can grow. When those devices are used, that bacteria can then get into a patient's body or blood and cause infection.
Cleaning and disinfection
Device sterilization
Hand hygiene
Use of personal protective equipment (gloves, gowns, eye protection)