HOW INFECTIONS OCCUR
Microbes (also called microorganisms) are very small living things that are found everywhere – in the water, air and soil. Microbes help our bodies to function. They keep us from getting sick. Sometimes, however, microbes cause disease and illness. If they grow too fast, or if they grow in the wrong places in our bodies, infections can result. Microbes that cause disease are called pathogens.
Several elements must be present for an infection to occur:
- A pathogen must be present.
- The pathogen needs a reservoir or a source where it can grow. People, animals, food, water, or insects can be the reservoirs. A person can have an infection and spread it to others but not even know he has the infection.
- Next, a portal of exit is needed. This is a way for the pathogen to leave the source. One example of a portal of exit would be drainage from a wound.
- A mode of transmission must be present. This is how the pathogen gets passed on from one person to another. Some of the ways this can happen are person-to-person contact (touch), coughing, sneezing, and dust carried in the air. Pathogens can also be spread through food, water, soil, objects, animals and insects.
- Pathogens need a portal of entry. This is a way to enter another person’s body. An open sore would be one example of a portal of entry. Another would be our breathing passages.
- Lastly, there must be a susceptible host. This is a person who is at risk for developing an infection. Elderly people or those who are ill often find it hard to fight infection. These people make susceptible hosts.
The items outlined above form the chain of infection. When all of these pieces are in place, infections can occur.
You may have heard the term nosocomial infection used at some time in the past. A nosocomial infection is one that occurs while a client is receiving care in a healthcare facility, such as a hospital. These infections often result in longer hospital stays for clients.
HOW INFECTIONS SPREAD
Infections spread through several modes or routes of transmission. These include contact transmission, airborne transmission, droplet transmission, vehicle, and vectorborne transmission.
Contact transmission can occur through direct or indirect contact. Direct contact involves the transfer of pathogens directly from one person to another. Indirect contact is the spread of infection through objects or surfaces.
Direct contact is often called person-to-person transmission. Microbes can pass from the person who has the infection to another person who can contract the infection. Infection can spread through contact involving the mucous membranes, all body fluids except sweat, and broken skin.
Sexual contact can pass on certain types of infection. Direct contact with an infected wound can spread disease. Healthcare workers sometimes pick up infections through needlestick injuries. When someone gets pricked with a contaminated needle, pathogens enter through the skin. An infection can arise.
Indirect contact can occur when a person comes in contact with a surface or an object that has been infected with a pathogen. These infected areas can be found on any surface. They could, for example, be found on the telephone, the stair rail, the bedpan, the doorknob, or a piece of equipment.
Airborne transmission refers to the spread of infection from person to person through very tiny pathogens in the air. These pathogens are small and light. They can stay up in the air for quite some time and travel long distances. These pathogens can be breathed in by a susceptible host.
Droplet transmission refers to the spread of disease through respiratory droplets in the air. Respiratory droplets are droplets that are expelled from the mouth or nose through the breathing tract. These droplets are larger and heavier than the airborne pathogen droplets. They do not travel very far or remain in the air for a long time.
Respiratory droplets can be forced up in the air through coughing, sneezing, talking, or laughing. Because they are so heavy, however, these droplets quickly fall back down. If another person is within three feet of the cough or sneeze, they may breathe them in. If these droplets are contaminated, an infection may result.
Some infections spread through food or water. This way of spreading infection is called vehicle transmission.
Bacteria are often killed during cooking or boiling. If we do not cook food properly, or if we drink contaminated water, we can get certain infections. Two common infections spread this way are salmonella infections and giardia. These infections can cause problems with our gastrointestinal tract and make us very ill.
Animals and insects can spread pathogens. This is called vectorborne transmission. An example would be when a mosquito or a tick bites an infected person and then bites someone else who is not infected. The healthy person can become sick with the disease from the infected person. Lyme disease and malaria are two examples of diseases spread by vectors.
WHY USE STANDARD PRECAUTIONS?
Standard precautions are steps that you should take to protect yourself when caring for others. They are intended to stop the spread of disease. Standard precautions are practiced in most healthcare facilities today.
Other types of precautions were developed before standard precautions came out. Two of these are universal precautions and body substance isolation.
Infections such as the Human Immunodeficiency Virus (HIV) and Hepatitis B led to the development of universal precautions in the 1980’s. Universal precautions is an approach to infection control that treats all blood and certain body fluids as if they were infected. It requires healthcare workers to wear proper equipment to protect themselves in certain situations. These situations include caring for clients who have broken skin or open sores or working with blood or body fluids that have visible signs of blood.
Sometimes, however, blood is present in body fluids even though we cannot see it. Universal precautions, when used alone, may not protect healthcare workers from body fluids that contain invisible traces of blood.
Body substance isolation (BSI)
Body substance isolation (BSI) was added to universal precautions as a protective measure. BSI states that protective equipment, such as gloves, gowns, masks and so on, must be worn in all situations working with body fluids. BSI has drawbacks, though. For example, it does not require healthcare workers to wash their hands when they take off their gloves. We now know, however, that gloves are not completely reliable. Small tears can appear in gloves. As well, pathogens can get inside the gloves when they are being put on or taken off.
In the mid 1990’s, standard precautions were developed. Standard precautions help stop the chain of infection and lower the chances of infection occurring. These protective measures combine universal precautions and body substance isolation techniques. They also go a step further as they assume that all body fluids, as well as mucous membranes, contain pathogens. Standard precautions apply to blood, all body fluids, secretions and excretions (except sweat), non intact skin (open or broken areas on skin), and mucous membranes. The Center for Disease Control and Prevention (CDC) now recommends that standard precautions be used for the care of all clients.
THE BASICS OF STANDARD PRECAUTIONS
Outlined below are basic guidelines for standard precautions:
Hand washing is the single most important thing that you can do to prevent infection.
Wash your hands:
When they are obviously soiled
After each contact with a possible source of infection such as blood, body fluids, mucus, a broken skin area, or an object that could be contaminated
After removing gloves
After contact with one person and before contact with another
Remember, too, to wash your hands between tasks and procedures on the same person or at anytime that pathogens might spread to other people or caregivers. Wash well with soap and warm water for at least 15 seconds. Scrub all surfaces of your hands. Dry with a clean towel.
Gloves help prevent the transfer of pathogens through direct or indirect contact. Wear non sterile gloves when you feel you may be in contact with blood or any other body fluids. This includes contact with broken skin, mucous membranes, and infected items or objects. Haul the cuffs of the gloves up you’re your wrists or over the cuffs of the gown you are wearing.
Hospital gloves are not totally bug-proof. Remove them and wash your hands after each procedure. Doing so will reduce the spread of germs.
Masks, eye protection and face shields
Wear any of these as needed to protect yourself from splashes or sprays of body fluids.
Wear a gown as needed to protect your clothing and skin from becoming soiled with any body fluids during procedures. The gown may or may not be disposable, depending on your agency’s policy.
Remove dirty gowns before leaving the client’s room. This may prevent germs from transferring out of the contaminated area. Be careful not to spread germs to your own clothing as you remove the gown.
Material and equipment
Handle material and equipment for each person with care. It must be cleaned properly if reusable or thrown away safely if disposable. Proper cleaning will help to ensure other people do not become infected with the pathogens.
Cleaning and disinfecting
Follow the policies and procedures on cleaning and disinfecting within your healthcare facility.
Handling of linen
Handle soiled linen in a way that prevents the transfer of germs. Use a leakproof bag so that soiled linen does not touch your skin or clothing. Never place soiled linen on the floor.
Sharps objects are those that can break the skin, such as needles, scalpels, and broken glass. Take extra caution when working with these objects. Discard them in the proper containers after use.
Don’t recap needles. If a needlestick injury occurs, follow the policy of your agency for dealing with the injury.
Spills of blood and body fluids should be contained and cleaned up right away by those who have been trained to deal with infectious material. Below are a few guidelines for cleaning up spills of blood or body fluids:
Put on gloves
Wear protective eyewear as needed
Use wiping materials that can be thrown away once the cleaning is finished
Place the soiled materials in a plastic bag and then in the garbage
Use a proper disinfectant agent
Your facility should have a policy on the handling of spills of blood or other body fluids. Find out what that policy is and follow it.
Revival of a client
Certain equipment (e.g. a mouthpiece) can protect workers from germs when a client needs to be revived by mouth-to-mouth breathing.
A private room is needed if the person follows very poor hygiene or has an infection that makes it advisable.
Transmission-based precautions are used when caring for people who have, or who are suspected to have, infections that are easily spread to others. Transmission-based precautions call for extra safety measures beyond those required by standard precautions.
The three types of transmission-based precautions are:
- Contact precautions
- Airborne precautions
- Droplet precautions.
Remember, standard precautions should be used along with any type of transmission-based precaution.
All three types of precautions require that the person be kept in a separate room or be isolated. Some people may be upset or may feel lower self-esteem because of all the safety measures that are taken on their account. Help the person to understand the reason for these precautions. Offer support and reassurance. Notify your supervisor if the person remains notably upset.
Contact precautions are used when people being cared for have, or are suspected of having, organisms or diseases that can easily spread to others through direct or indirect contact. Direct contact involves direct contact with another person, such as when you bathe or turn a person. Indirect contact could involve touching an object that has become infected with pathogens.
Certain types of infections have become resistant to most of the drugs that are available to treat them. These infections are called multi-drug resistant infections. You may have heard of MRSA. MRSA stands for methecillin resistant staphylococcus aureus. MRSA is one example of a multi-drug resistant infection that is difficult to treat.
You would use contact precautions to care for someone who has a multi-drug resistant infection. A few of the other conditions that require use of contact precautions are widespread shingles, scabies, impetigo, chicken pox, and head or body lice.
Contact precautions involve the following measures:
- Private room
The person should be placed in a private room or with another person who has the same infection.
Apply gloves before entering the room and remove them prior to leaving it.
Use an antibacterial soap to wash your hands after removing the gloves.
Wear a gown before going into the person’s room. Remove it before leaving the room.
- Moving people
When moving the person, maintain precautions so the chances of spreading disease are reduced.
Each person should be assigned his/her own equipment while under contact precautions.
Airborne precautions are used to prevent infectious diseases from spreading through the air. Airborne precautions require a private room with negative pressure. The negative pressure filters and cleans the air so that pathogens cannot be passed around to others. Keep the door closed except when you have to enter or leave the room. This allows the air filter system to work as it should.
Airborne precautions are used for diseases such as measles, chicken pox, or widespread shingles. It is also used for suspected or confirmed cases of tuberculosis (TB). Some of these conditions also require the use of contact precautions. The person in your care could have three types of precautions (standard, contact, and airborne) in place all at the same time.
Persons who have not already had chicken pox or measles are at high risk for catching those diseases. They should not enter the room of a person who has either of these conditions. If they must do so, however, they should wear a special protective mask or device. A respirator mask provides particular protection in these cases.
The pathogens that cause airborne infections are very tiny. They can easily travel through the larger pores on common surgical masks. A respirator mask filters out small particles spread by the airborne route. Respirator masks would not be needed for those who have already had chicken pox or measles.
Droplet precautions are used when diseases are spread through droplets – usually by coughing, sneezing, or talking. A regular surgical mask can be worn to prevent the spread of these respiratory droplets. That’s because the droplets are fairly large and cannot pass through the pores of a surgical mask.
Respiratory droplets are most often located within three feet of the person. It is safer to wear a mask while you are in the room, however, even if you are more than three feet away. The person should have a single room. Mumps, German measles, diphtheria, rubella, certain types of pneumonia, and scarlet fever in infants and young children are some of the conditions that would require droplet precautions.
ABOUT BLOODBORNE PATHOGENS
Bloodborne pathogens are pathogens that are spread through blood or other body fluids. The most important ones for you and other caregivers to be concerned about are Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV), and Hepatitis C Virus (HBC).
HIV harms the immune system. When the immune system doesn’t work properly, infections, and even cancer, may result. About a million people in the US have HIV. Acquired Immunodeficiency Syndrome (AIDS) is a very serious disease that results from HIV infection. There is no cure for AIDS. Infected persons must take precautions not to pass the virus on to others.
Viruses that attack the liver can cause Hepatitis B and Hepatitis C. An estimated 1.25 million people carry the virus for Hepatitis B in the US. Hepatitis C may be the most common bloodborne pathogen in the US; about 4 million Americans have the disease.
These infections can lead to chronic liver disease, liver cancer, and even death. A vaccine is available to prevent Hepatitis B. There is no vaccine against Hepatitis C.
Bloodborne pathogens can spread by sharing needles with an infected person, through sexual contact with an infected person, getting stuck with a contaminated needle, or through direct contact with contaminated blood or body fluids, such as touching an open wound or handling infected fluid. An infected mother can also pass these viruses on to her unborn baby.
Following standard precautions is one way to protect yourself and others against bloodborne pathogens. You cannot tell if someone has an infection by the way they look. That is why it is so important to practice standard precautions with everyone you care for.
RESPONSIBILITIES OF THE CAREGIVER
As a caregiver, you should make a point of learning as much as you can about health and safety. Attend educational sessions when possible. Practice what you have learned. Know and follow workplace policies on infection control.
Protect your own health and the health of the people in your care. If you have not been vaccinated against hepatitis B, consult with your doctor. Use gloves, masks, gowns, and other equipment as needed. Don’t forget about the importance of good handwashing – the first defense against infection.
Know and understand the materials you are using. Be able to dispose of materials properly.
Standard precautions help reduce the spread of infection from one patient to another, to caregivers, or to visitors. Maintain a healthy lifestyle in your everyday life. Report any signs of infection when first observed.
CHALLENGES TO INFECTION CONTROL
Infection control has many challenges. Following standard precautions while caring for someone in their home can be hard to do. Areas of the household may be visibly dirty. Soap or clean towels may not always be on hand. Realize that these situations may crop up. Discuss “What if” scenarios with your supervisor to plan for challenges like these.
The increase in allergies is another problem in infection control today. 8-12% of healthcare workers have been found to be allergic to latex. Those employees cannot wear latex gloves. Latex allergies can cause reactions such as skin irritations, rashes, and breathing problems.
To protect yourself from latex allergies, wash and dry your hands well after removing gloves. If you think you may be allergic to latex or to the powder within latex gloves, contact your doctor. If you are allergic, there are gloves available that are latex-free and powder-free.
As a caregiver, you must work hard to break up the chain of infection. Follow standard precautions for all people in your care. Follow other types of precautions as ordered. Know and follow your agency’s policies on health and safety and on infection control. Attend training sessions offered by your agency. Protect yourself from infection in your private life.
CHECK YOUR KNOWLEDGE
What is the chain of infection?
Describe how infections are spread.
Explain the purpose of standard precautions.
Discuss the use of gloves in standard precautions.
Name three bloodborne pathogens.
Identify your responsibilities as a caregiver with respect to infection control.
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