INFECTION CONTROL - Principles of Health Sciences - ثاني ثانوي

Link to digital lesson CHAPTER www.ien.edu.sa 2 INFECTION CONTROL Case Study Investigation Fahad and Ayisha worked as nurses at University Hospital during the coronavirus disease 2019 (COVID-19) pandemic. They worked in the emergency room (ER) and needed to be aware of how this virus was transmitted so they could use the proper personal protective equipment (PPE). After they went through training, they understood that this disease was highly contagious and potentially deadly. Fahad and Ayisha knew that patients would sometimes have to remain in the ER for extended periods of time waiting on test results, and they would have to use correct precautions when interacting with those patients. At the end of this chapter, you will be asked what PPE they needed to use and why. I LEARNING OBJECTIVES After completing this chapter, you should be able to: • Identify the basic principles of infection and infection control. • Wash hands following aseptic technique. • Observe standard precautions needed while working in the laboratory or clinical area. • Follow basic principles of sterilization, disinfection, ultrasonic cleaning, and sterile techniques. • Explain how to care for patients in a transmission-based isolation unit. KEY TERMS bacteria chain of infection chemical disinfection contamination microorganism parasite pathogens 28 CHAPTER 2 وزارة التعليم Ministry of Education 2022-1444 DESPLWWW.0 32 HI TH 58 oth sterilization ultrasonic cleaning viruses 18012023 1429

وزارة التعليم 2:1 UNDERSTANDING THE PRINCIPLES OF INFECTION CONTROL A microorganism, or microbe, is a small living organism that is not visible to the naked eye. It must be viewed under a microscope. Microorganisms are found everywhere in the environment, including on and in the human body (our microbiome). Microorganisms which are beneficial in maintain- ing certain body processes are called nonpathogens. Other microorganisms cause infection and disease, and are called pathogens, or germs. A parasite is an organism that lives in or on an organism of another spe- cies (its host) and benefits by getting nutrients at the host's expense. Parasitic infections can be spread through contaminated water, food, waste, soil, and blood. Some parasites are spread by insects that act as a vector, or carrier, of the disease. To grow and reproduce, microorganisms need certain things. Most microorganisms prefer a warm environment, and body temperature is ideal. Most microorganisms also prefer darkness, and many are killed quickly by sunlight. In addition, a source of food and moisture is needed. Some micro- organisms, called aerobic organisms, require oxygen to live. Others, called anaerobic organisms, live and reproduce without oxygen. The human body is the ideal supplier of all the requirements of microorganisms. There are many different classes of microorganisms. In each class, some are pathogenic (harmful) to humans: . Bacteria are simple, single-celled organisms that multiply rapidly (Figure 2-1). Diseases caused by different types of bacteria include tuberculosis, teta- nus, pertussis (whooping cough), botulism, diphthe- ria, and typhoid. Antibiotics are used to kill bacteria, but because they have been overused, some strains of bacteria have now become antibiotic-resistant. This means that most antibiotics are no longer effective against them. If a bacterium becomes resistant to several drugs, it is called multidrug-resistant, or a "superbug". Methicillin-resistant Staphylococcus aureas (MRSA) is an example. All antibiotic-resist- ant bacteria are a major concern because they are difficult to treat, cause increased hospital stays, and increase the cost of health care. FIGURE 2-1 Rod-shaped bacteria called Enterobacteriaceae, which are part of the normal intestinal microbiome. They are also the causative agents of different infections. ⚫ Rickettsiae are parasitic bacteria that can only live inside the cells of another living organism. They are commonly found in fleas, lice, ticks, and mites, and are transmitted to humans by the bites of these insects. Rickettsiae cause diseases such as typhus fever and Rocky Mountain spotted fever. Antibiotics are effective against many different rickettsiae. Minor Educ 2022 1444 GE44.PATHWAYS.002.S2.HLTH.58.indb 29 INFECTION CONTROL 29 | 18/01/2023 14:29

FIGURE 2-2 An intestinal protozoan, Giardia intestinalis, is the blue mass in the center of the photo. FIGURE 2-3 The yeast (fungus) called thrush causes these characteristic white patches on the tongue and in the mouth. (A) ⚫ Protozoa are single-celled animal-like organisms often found in decayed materials, animal or bird feces, insect bites, and contaminated water (Figure 2-2). Many con- tain flagella (long tails), which allow them to move freely. Protozoa cause diseases such as malaria, amebic dysentery (intestinal infection), trichomonas, and African sleeping sickness. Treatment of protozoa infections can be lengthy and is not always successful. Fungi are simple, plant-like organisms that live on dead organic matter and can infect humans. Yeasts and molds are two common forms that can cause diseases such as ringworm, athlete's foot, histoplasmosis, yeast vaginitis, and thrush (Figure 2-3). Antifungal medications are available for many of the pathogenic fungi, but they are expensive, must be taken for a long period, and may cause liver damage. ⚫ Viruses are visible only using an electron microscope. They cannot reproduce unless they are inside a living cell. They are spread from human to human by blood and other body secretions. Viruses are more difficult to kill because they are resistant to many disinfectants and are not affected by antibiotics. Viruses cause many diseases, including the common cold, measles, mumps, chickenpox, herpes, warts, influenza (Figure 2-4A), and polio. New and different viruses, like the new coro- navirus that caused COVID-19 (Figure 2-4B), emerge constantly because viruses are prone to mutating and changing their genetic information. Viruses that infect animals can mutate to infect humans, often with lethal results. Helminths are multicellular parasitic organisms com- monly called worms or flukes. They are transmitted to humans when humans eat the eggs or larvae in contam- inated food, eat meat contaminated with the worms, (B) FIGURE 2-4 (A) Electron micrograph of the influenza virus. (B) Electron micro- graph of a coronavirus. FIGURE 2-5 Hookworms attached to the mucosal lining of the intestine are one type of helminth. 30 CHAPTER 2 وزارة التعليم Missing or Educosine 2022 1444 GE44 PATHWAYS.G02.82.HLTH.S8.indb 30 18/01/2023 14:29

وزارة التعليم or get bitten by infected insects. Some worms can also penetrate the skin to enter the body. Examples of helminths include hookworms, which attach to the small intestine and can infect the heart and lungs (Figure 2-5), ascarids, which live in the small intestine and can cause an obstruction of the intestine, and pinworm, which mainly affects young children. Specific drugs are used to treat helminth infections. When one individual in a family is found to be infected, other fam- ily members should be treated as well, particularly in cases such as threadworm. TYPES OF INFECTION Microorganisms can cause infection and disease in different ways. Some produce poisons, called toxins, which harm the body. Some cause an allergic reaction in the body, resulting in a runny nose, watery eyes, and sneezing. Other microorganisms attack and destroy the living cells they invade. Infections and diseases are also classified as endogenous, exogenous, health care-associated, or opportunistic: . An endogenous infection is an infection that originates within the body. An example is tuberculosis, infection by a microorganism which is dormant in the body. ⚫ An exogenous infection is an infection that originates outside the body. An example is a staphylococcal skin infection, pathogenic organisms that invade the body. A health care-associated infection (also called nosocomial or hospi- tal-acquired) is an infection acquired by an individual in a health care facility. An example is Pseudomonas in a wound infection. ⚫ Opportunistic infections are those that occur when the body's defenses are weak. These diseases do not usually occur in individu- als with intact immune systems. An example is the development of a yeast infection called candidiasis. VACCINES Vaccines are used to prevent disease. A vaccine stimulates the immune system to produce antibodies, similar to the antibodies made by the body after exposure to a disease. They are made from very small amounts of weakened or dead germs. After getting vaccinated, an individual develops immunity to that disease without having to get the disease first. Vaccinations protect both the individuals getting them and the com- munity from the disease. Germs can travel quickly through a community and cause a major outbreak of a disease. If enough people are vaccinated against a certain disease, the germs cannot travel as easily from person to person and the entire community is less likely to get the disease. Ministing or Education 2022-1444 GE44.PATHWAYS.002.82.HLTH.58.indb 31 INFECTION CONTROL 31 | 18/01/2023 14:29

CHAIN OF INFECTION For disease to occur and spread from one individual to another, certain conditions must be met. These conditions are commonly called the chain of infection (Figure 2-6). The parts of the chain include: ⚫ An infectious agent: A pathogen, such as a bacterium or virus that can cause a disease. . A reservoir: An area where the infectious agent can live, like the human body, animals, and contaminated objects (for example, doorknobs, bedpans, urinals, linens, instruments, and specimen containers). Treatment of underlying diseases Recognition of high-risk patients Immunization to prevent disease Susceptible host Wound care Entry Catheter care Medical asepsis Standard- precautions Standard- precautions Handwashing- Sterilization Early recognition of signs of infection Rapid, accutrate identification of organisms Infectious agent Involves all health care team members- YOU Mode of transmission Medical asepsis Standard precautions Employee health Environmental Reservoir sanitation Disinfection/ Sterilization Medical asepsis Exit Personal protective equipment Handwashing Control of excretions and secretions Trash and waste disposal Standard precautions Transmission-based precautions -Food handling Medical asepsis Air flow control FIGURE 2-6 The components in the chain of infection and the ways in which the chain can be broken. 32 CHAPTER 2 وزارة التعليم Ministing or Em cupion 2022-1444 GE44 PATHWAYS.G02.82.HLTH.S8.indb 32 18/01/2023 14:29

وزارة التعليم . An exit: A way for the infectious agent to escape from the reservoir where it has been growing. In the human body, pathogens can leave the body through urine, feces, saliva, blood, tears, mucous discharge, other bodily secretions, and draining wounds. . A mode of transmission: A way that the infectious agent can be transmitted to another reservoir or host where it can live. The patho- gen can be transmitted by: Direct contact, which includes person-to-person contact, like con- taminated hands. •Indirect contact, from contaminated substances such as food, air, soil, insects, feces, clothing, instruments, and equipment. An entry: A way for the infectious agent to enter a new reservoir or host, for example through breaks in the skin or by breathing it in. BODY DEFENSES If body defenses are intact and the immune system is functioning, a human can fight off infection and not contract a disease. Body defenses include: Mucous membranes: Linings of the respiratory, digestive, and repro- ductive tracts that trap pathogens. ⚫ Cilia: Tiny, hair-like structures that line the respiratory tract and push pathogens out of the body. ⚫ Coughing and sneezing: Expel pathogens out of the body. ⚫ Hydrochloric acid: Destroys pathogens in the stomach. ⚫ Tears in the eye: Contain chemicals that kill bacteria. ⚫ Fever: High temperatures destroy some pathogens. ⚫ Inflammation: Leukocytes, or white blood cells, destroy pathogens. ⚫ Immune response: The body produces antibodies, protective proteins that combat pathogens. If your body defenses are weak, you are more likely to get an infection or disease. If any part of the chain is eliminated, the spread of disease or infection will be stopped. Health care providers should follow practices to interrupt or break this chain and prevent the transmission of disease. Ministry of Em.cupon 2022-1444 GE44.PATHWAYS.002.82.HLTH.58.indb 33 INFECTION CONTROL 33 | 18/01/2023 14:29

34 CHAPTER 2 وزارة التعليم Ministry or Education 2022-1444 GE44 PATHWAYS.G02.82.HLTH.58.indb 34 ASEPTIC TECHNIQUES A major way to break the chain of infection is to use aseptic techniques while providing health care. Terms used in this field: ⚫ Asepsis is the absence of disease-producing microorganisms (pathogens). ⚫ Sterile means free from all organisms, both pathogenic and nonpath- ogenic, including spores and viruses. ⚫ Contaminated means that organisms and pathogens are present. Any object or area that may contain pathogens is considered to be contaminated. Aseptic techniques help to eliminate or prevent contamination, including: ⚫ Handwashing. ⚫ Use of disposable gloves when contacting body secretions or contam- inated objects. ⚫ Proper cleaning of instruments and equipment. • ⚫Thorough cleaning of the environment. Various levels of aseptic control are possible: ⚫ Antisepsis: Antiseptics prevent or inhibit growth of pathogenic organisms but are not effective against spores and viruses. They can usually be used on the skin. Common examples of antiseptics include alcohol and iodine. ⚫ Disinfection: Chemical disinfectants are used to destroy or kill path- ogenic organisms. They are not always effective against spores and viruses. Disinfectants can irritate or damage the skin and are used mainly on objects, not people. Some common disinfectants are bleach solutions and benzalkonium chloride. ⚫ Sterilization: Destroys all microorganisms, both pathogenic and nonpathogenic, including spores and viruses. Steam under pressure, gas, radiation, and chemicals can be used to sterilize objects. An auto- clave is the most common piece of equipment used for sterilization. checkpoint 1. What is the difference between a pathogen and a nonpathogen? 2. How many components are in the chain of infection? 18/01/2023 14:29

2:2 WASHING HANDS Handwashing is the single most impor- tant method used to practice aseptic Precaution technique (Figure 2-7). Thoroughly washing the hands helps to prevent and control the spread of pathogens from one person to another. It also helps protect health care pro- viders from disease and illness. The World Health Organization has devel- oped guidelines for handwashing, called My 5 Moments for Hand Hygiene. The five essential times for handwashing include: ⚫ Before touching a patient. ⚫ Before a clean or aseptic procedure. After body-fluid exposure or risk of exposure. After touching a patient. After touching the patient's surroundings. In addition, you should wash your hands: FIGURE 2-7 Handwashing is the most important method used to practice aseptic technique. ⚫ When you arrive at the facility and before leaving the facility. . After contact with a patient's intact skin (for example, after taking a blood pressure). ⚫ Before moving from a contaminated body site to a clean body site during patient care (for example, before washing the patient's hands after removing a bedpan). Any time the hands become contaminated during a procedure. Before applying and immediately after removing gloves. ⚫ Any time gloves are torn or punctured. Before and after handling any specimen. After contact with any soiled or contaminated item. . After picking up any item off the floor. After personal use of the bathroom. ⚫ After you cough, sneeze, or use a tissue. Before and after any contact with your mouth or mucous membranes, such as eating, drinking, applying lip balm, or inserting or removing contact lenses. وزارة التعليم Mistojo ECHDIOC 2022-1444 GE44.PATHWAYS.002.82.HLTH.58.indb 35 INFECTION CONTROL 35 | 18/01/2023 14:29

(A) (B) (C) (D) (E) FIGURE 2-8 (A) Use a dry towel to turn the faucet on. (B) Point the fingertips downward and use the palm of one hand to clean the back of the other hand. (C) Interlace the fingers to clean between the fingers. (D) A hand brush can be used to clean the nails. (E) With the fingertips pointing downward, rinse the hands thoroughly. HANDWASHING WITH SOAP AND WATER Follow a standard procedure to ensure thorough cleaning (Figure 2-8). The principles that should be observed whenever hands are washed are: ⚫ Soap is used as a cleansing agent because it aids in the removal of germs through its sudsy action and alkali content. Pathogens are trapped in the soapsuds and rinsed away. Liquid soap from a dispenser should be used whenever possible because bar soap can contain microorganisms. ⚫ Warm water should be used. This is less damaging to the skin than hot water. It also creates a better lather with soap than does cold water. ⚫ Friction must be used in addition to soap and water. This action helps rub off pathogens from the surface of the skin. . All surfaces on the hands must be cleaned. This includes the palms, the backs/tops of the hands, and the areas between the fingers. ⚫ Fingertips must be pointed downward. The downward direction pre- vents water from getting on the forearms and then running down to contaminate the clean hands. Dry paper towels must be used to turn the faucet on and off. This action prevents contamination of the hands from pathogens on the faucet. A dry towel must be used because pathogens can travel more readily through a wet towel. ⚫ Nails also harbor dirt and pathogens; they must be cleaned during the handwashing process. WATERLESS HANDWASHING Waterless handwashing with an alcohol-based gel, lotion, or foam has been proved safe for use during routine patient care (Figure 2-9). Most waterless handwashing products contain at least 60-90 percent alcohol, and a moisturizer to prevent drying of the skin. Its use is recommended when the hands are not visibly dirty and are not contaminated with blood or body fluids: ⚫ Read the manufacturer's instructions before using any product. Apply a small amount of the alcohol-based cleaner to the palm of your hands. Rub your hands vigorously so the solution is applied to all surfaces of the hands, fingers, nails, and wrists. ⚫ Rub until your hands are dry, usually at least 20-30 seconds. 36 CHAPTER 2 وزارة التعليم Mousing or Educon 2022-1444 GE44 PATHWAYS.G02.82.HLTH.S8.indb 36 18/01/2023 14:29

Most manufacturers recommend that the hands be washed with soap and water after 6-10 clean- ings with the alcohol-based product. In addition, if the hands are visibly soiled, or if there has been contact with blood or body fluid, the hands must be washed with soap and water. checkpoint 1. What is the single most important method used to practice aseptic technique? 2. What are the World Health Organization's five essential times for handwashing? 2:3 OBSERVING STANDARD PRECAUTIONS FIGURE 2-9 Waterless handwashing using an alcohol-based cleaner is an effective way to clean hands that are not visibly soiled. To prevent the spread of pathogens, the chain of infection must be broken. Standard precautions must be used in any situation Precaution where health care providers may come into contact with: ⚫Blood or any fluid that may contain blood. Body fluids, secretions, and excretions, such as mucus, sputum, saliva, cerebrospinal fluid, urine, feces, or vomit. • Mucous membranes. Nonintact (broken) skin. ⚫Tissue or cell specimens. The basic standard precautions include: ⚫ Handwashing. ⚫ Gloves must be worn whenever contact with blood, body fluids, secretions, excretions, mucous membranes, or nonintact skin is possible; when handling or cleaning any contaminated items or surfaces; when taking blood for testing (Figure 2-10). Gloves must be changed after contact with each patient and even between tasks or procedures on the same patient if there is any chance that the gloves are contaminated. FIGURE 2-10 Gloves must be worn whenever con- tact with blood, body fluids, secretions, excretions, mucous membranes, or nonintact skin is possible. وزارة التعليم Minisiojo Encon 2022-1444 GE44.PATHWAYS.002.82.HLTH.58.indb 37 INFECTION CONTROL 37 | 18/01/2023 14:29

FIGURE 2-11 Gloves, a gown, a mask, and protective eyewear or face shields must be worn during any procedure that may produce splashes or sprays of blood, body fluids, secre- tions, or excretions. FIGURE 2-12 The safety syringe is one exam- ple of a safer device to prevent needlesticks. FIGURE 2-13 All needles and sharp objects must be discarded immediately in a leakproof, puncture-resistant sharps container. ⚫ Gowns must be worn during any procedure that may cause splashing or spraying of blood, body fluids, secretions, or excretions. This helps to pre- vent contamination of clothing or uniforms. Gowns should only be worn once and then discarded. Gowns should not be worn out of patient rooms or care areas. Masks and protective eyewear or face shields (Figure 2-11) must additionally be worn during procedures that may produce splashes or sprays of blood, body fluids, secretions, or excretions. Examples include irrigation of wounds, suctioning, dental procedures, delivery of a baby, and surgical procedures. This prevents exposure of the mucous membranes of the mouth, nose, and eyes to any path- ogens. Masks must be used once and then discarded. To avoid accidental cuts or punctures, extreme care must be taken while handling sharp objects. Whenever possible, safe needles or needleless devices should be used (Figure 2-12). Disposable needles must never be bent or broken after use. They must be left uncapped and attached to the syringe and placed in a leakproof, puncture-resistant sharps container (Figure 2-13). The sharps container must be labeled with a red biohazard symbol (Figure 2-14). Surgical blades, razors, and other sharp objects must also be discarded in the sharps container. ⚫ Spills or splashes of blood, body fluids, secretions, or excretions must be wiped up immediately. Gloves must be worn while wiping up the area with dispos- able cleaning cloths. The area must then be cleaned with a disinfectant solution such as a 10% bleach solution. Furniture or equipment contaminated by the spill or splash must be cleaned and disinfected immediately. For large spills, an absorbent powder may be used to soak up the fluid. After the fluid is absorbed, the powder is swept up and placed in an infectious waste container. Mouthpieces or resuscitation devices should be used instead of mouth-to-mouth resuscitation. They should be placed in convenient locations and be read- ily accessible for use. If they are not disposable, they must be disinfected between patient use. 38 CHAPTER 2 وزارة التعليم Missing or Educion 2022 1444 GE44 PATHWAYS.G02.82.HLTH.58.indb 38 18/01/2023 14:29

وزارة التعليم ⚫. Infectious waste such as contaminated dressings, gloves, bedpans, and body tissues must be placed in infectious waste or biohazardous material bags. Other waste is placed in plastic bags and incinerated. Soiled linen should be placed in laundry bags to prevent any con- tamination. Any bag containing contaminated linen must be clearly labeled and color-coded. Any cut, injury, needlestick, or splashing of blood or body fluids must be reported immediately. Report and document any exposure or injury, record the care given, note any follow-up to the exposure incident, and identify ways to prevent a similar incident. BLOODBORNE PATHOGENS One of the main ways in which pathogens are spread is by blood and body fluids. Three pathogens of major concern are the hepatitis B virus (HBV), the hepatitis C virus (HCV), and the human immunodeficiency virus (HIV). Consequently, extreme care must be taken at all times when an area, object, or person is contaminated with blood or body fluids: ⚫ Use PPE such as gloves, gowns, lab coats, masks, and face shields. • Provide adequate handwashing facilities and supplies. •Ensure that the worksite is maintained in a clean and sanitary condition. ⚫ Follow measures for immediate decontamination of any surface that comes into contact with blood or infectious materials, and dispose of infectious waste correctly. Enforce rules of no eating, drinking, applying cosmetics or lip balm, handling contact lenses, and mouth pipetting or suctioning in any area that can be potentially contaminated by blood or other body fluids. Provide appropriate containers that are color-coded (fluorescent orange or orange-red) and labeled for contaminated sharps (needles, scalpels) and other infectious or biohazard wastes. Post signs at the entrance to work areas where there is occupational exposure to biohazardous materials. Label any item that is biohazardous with the red biohazard symbol (Figure 2-14). checkpoint 1. How many times should a mask be used before it is discarded? 2. What is PPE? BIOHAZARD FIGURE 2-14 The uni- versal biohazard symbol indicates a potential source of infection. Ministry of Education 2022 1444 GE44.PATHWAYS.002.82.HLTH.58.indb 39 INFECTION CONTROL 39 | 18/01/2023 14:29

2:4 STERILIZATION, DISINFECTION, ULTRASONIC CLEANING FIGURE 2-15 An auto- clave uses steam under pressure or gas to steril- ize items. STERILIZATION Sterilization of instruments and equipment is essential in preventing the spread of infection. The autoclave is the safest and most efficient steriliza- tion method. An autoclave is a piece of equipment that uses steam under pressure or gas to sterilize equipment and supplies (Figure 2-15). It will destroy all microorganisms, both pathogenic and nonpathogenic, includ- ing spores and viruses. ⚫ Equipment to be sterilized must be prepared properly. All items must be washed thoroughly and then rinsed. ⚫Items that are to remain sterile must be wrapped in a material (for example, muslin, autoclave paper, special plastic or paper bags, and autoclave containers) that will allow for the penetration of steam dur- ing the autoclaving process. ⚫ Sterilized items must be stored in clean, dustproof areas. Items usually remain sterile for 30 days after autoclaving. ⚫ Some autoclaves are equipped with a special door that allows the autoclave to be used as a dry-heat sterilizer. Dry heat involves the use of a high temperature for a long period. The temperature is usually a minimum of 160-177°C (320-350°F). The minimum time is usually 60 minutes. ⚫ Dry-heat sterilization is a good method for sterilizing instruments that may corrode, such as knife blades, or items that would be destroyed by the moisture in steam sterilization, such as powders. ⚫ An oven can be used for dry-heat sterilization in home situations. USING CHEMICALS FOR DISINFECTION Chemicals are frequently used for aseptic control. However, many chemi- cals do not kill spores and viruses, so chemicals are not a method of ster- ilization. Because sterilization does not occur, chemical disinfection is the correct term (rather than cold sterilization, a term that is sometimes used). A few chemicals kill spores and viruses, but they often require that instruments be submerged in the chemical for 10 hours or more. . ⚫ Chemicals are used to disinfect instruments that do not penetrate body tissue, such as dental instruments, tweezers, and scissors (Figure 2-16). 40 CHAPTER 2 وزارة التعليم Mistojo Edicion 2022 1444 GE44 PATHWAYS.G02.82.HLTH.S8.indb 40 18/01/2023 14:29

وزارة التعليم Ministry of Education 2022-1444 Chemicals are used to disinfect thermometers and other items that would be destroyed by the high heat used in the autoclave. ⚫Proper cleaning of all instruments or articles is essential. They must be rinsed thoroughly because the presence of soap can also reduce the effectiveness of chemicals. The articles must be dry before being placed in the disinfectant to keep the chemical at its most effective strength. The chemical disinfectant must completely cover the article. This is the only way to be sure that all parts of the article will be disinfected. In addition, the items should be separate so each one will come into contact with the chemical. FIGURE 2-16 Chemicals are used to disinfect instruments that do not penetrate body tissue, such as dental instruments, tweezers, and scissors. Before removing items from solutions, health care providers must wash their hands. Sterile gloves or sterile pick-ups or transfer forceps may be used to remove the instruments from the solution. The items should be rinsed with sterile water to remove any remaining chemical solution. After rinsing, the instruments are placed on a sterile towel to dry, and then stored in a drawer or dust-free closet. CLEANING WITH AN ULTRASONIC UNIT Ultrasonic units are used to remove dirt, debris, blood, saliva, and tissue from a large variety of instruments before sterilizing them. . Ultrasonic cleaning uses sound waves to clean. When the ultrasonic unit is turned on, the sound waves produce millions of microscopic bubbles in a cleaning solution. When the bubbles strike the items being cleaned, they explode (a process known as cavitation) and drive the cleaning solution onto the article. Accumulated dirt and residue are easily and gently removed from the article. Ultrasonic cleaning is not sterilization because spores and viruses remain on the articles. If sterilization is desired, other methods must be used after the ultrasonic cleaning. A general, all-purpose cleaning solution is used most of the time. . Many different items can be cleaned in an ultrasonic unit, including instruments, dental impression trays, and glass products. checkpoint 1. What is an autoclave? 2. What kinds of instruments are disinfected using chemicals? GE44.PATHWAYS.G02.82.HLTH.58.indb 41 INFECTION CONTROL 41 | 18/01/2023 14:29

2:5 USING STERILE TECHNIQUES While working with sterile supplies, it is important that correct tech- niques be followed to maintain sterility and avoid contamination. It is also important to recognize sterile surfaces and contaminated surfaces. ⚫ A clean working area is required when working with sterile supplies. . A sterile object must never touch a nonsterile object. If other objects are in the way, it is easy to contaminate sterile articles. If sterile arti- cles touch the skin or any part of your clothing, they are no longer sterile. Because any area below the waist is considered contaminated, sterile articles must be held away from and in front of the body and above the waist. . Once a sterile field has been set up, never reach across the top of the field. Microorganisms can drop from your arm or clothing and contaminate the field. Avoid coughing, sneezing, or talking over the sterile field because airborne particles can fall on the field and con- taminate it. • ⚫ The 5-cm (2-inch) border around the sterile field is considered con- taminated, so 5 cm (2 inches) around the outside of the field must not be used when sterile articles are placed on the sterile field. ⚫ All sterile items must be checked carefully before they are used. If an item has been autoclaved and dated, most health care facilities believe the date should not be more than 30 days from autoclaving. If tears or stains are present on the package, the item should not be used because it could be contaminated. If there are any signs of moisture on the package, it has been contaminated and should not be used. FIGURE 2-17 Sterile items can be dropped from the wrapper onto the sterile field. ⚫ Organisms and pathogens travel quickly through a wet surface, so the sterile field must be kept dry. If a sterile towel or article gets wet, contamination has occurred. It is very important to use care when pouring solutions into sterile bowls or using solu- tions around a sterile field. ⚫ Various techniques can be used to remove articles from sterile wraps, depending on the article being unwrapped. Some common techniques are the drop technique (Figure 2-17), used for gauze pads, dressings, and small items; the mitten technique, used for bowls, drapes, linen, and other similar items; and transfer-forceps techniques used 42 CHAPTER 2 وزارة التعليم Minising or Emcision 2022-1444 GE44 PATHWAYS.G02.82.HLTH.S8.indb 42 18/01/2023 14:29

وزارة التعليم for cotton balls, small items, or articles that cannot be removed by the drop or mitten techniques. . Make sure that the sterile tray is open, and you are ready to carry out the sterile procedure before putting the sterile gloves on your hands. ⚫ Sterile gloves are considered sterile on the outside and contaminated on the inside (the side against the skin). Once they have been placed on the hands, it is important to hold the hands away from the body and above the waist to avoid contamination (Figure 2-18). Handle only sterile objects while wearing sterile gloves. DONNING AND REMOVING STERILE GLOVES 1. Check the package for stains, tears, moisture, or evidence of contamina- tion. Do not use the package if there is any evidence of contamination. 2. Remove rings. Wash hands. Dry hands thoroughly. 3. Open the package containing the gloves, taking care not to touch the inside of the inner wrapper. The inner wrapper contains the gloves. Reach in from the sides to open the inner package and expose the sterile gloves (Figure 2-19A). The folded cuffs will be nearest to you. If you touch the inside of the package (where the gloves are), get a new package and start again. 4. The glove for the right hand will be on the right side, and the glove for the left hand will be on the left side of the package. With the thumb and forefinger of the nondominant hand, pick up the top edge of the folded-down cuff (inside) of the glove for the dominant hand. Remove the glove carefully (Figure 2-19B). Do not touch the outside. This is sterile. Only the part that will be next to the skin can be touched. Remember: unsterile touches unsterile and sterile touches sterile. FIGURE 2-18 Once sterile gloves have been placed on the hands, hold the hands away from the body and above the waist to avoid contamination. Mesinjo Educloon 2022-1444 GE44.PATHWAYS.002.82.HLTH.58.indb 43 INFECTION CONTROL 43 | 18/01/2023 14:29

44 CHAPTER 2 وزارة التعليم Ministry of Education 2022-1444 GE44 PATHWAYS.G02.82.HLTH.58.indb 44 5. Hold the glove by the inside cuff and slip the fingers and thumb of your other hand into the glove. Pull the glove on carefully (Figure 2-19C). Hold the glove away from the body. Pull gently to avoid tear- ing the glove. 6. Insert your gloved hand under the cuff (outside) of the other glove and lift the glove from the package (Figure 2-19D). Do not touch any other area with your gloved hand while removing the glove from the package. If contamination occurs, discard the gloves and start again. 7. Holding your gloved hand under the cuff of the glove, insert your other hand into the glove (Figure 2-19E). Keep the thumb of your gloved hand tucked in to avoid possible contamination. 8. Turn the cuffs up by manipulating only the sterile surface of the gloves (sterile touches sterile). Go up under the folded cuffs, pull out slightly, and turn the cuffs over and up (Figure 2-19F). Do not touch the inside of the gloves or the skin with your gloved hand. 9. Interlace the fingers to position the gloves correctly, taking care not to touch the skin with the gloved hands (Figure 2-19G). If contamina- tion occurs, start again with a new pair of gloves. 10. Do not touch anything that is not sterile once the gloves are in place. Gloved hands should remain in position above the waist. Do not allow them to fall below the waist. 11. After the procedure requiring sterile gloves has been completed, dis- pose of all contaminated supplies before removing the gloves. This reduces the danger of cross-infection caused by handling contami- nated supplies without glove protection. 12. To remove the gloves, use one gloved hand to grasp the other glove by the outside of the cuff (Figure 2-19H). Taking care not to touch the skin, remove the glove by pulling it down over the hand (Figure 2-191). It will be wrong side out when removed. This prevents contamination of your hands by organisms picked up while performing the proce- dure. Now the outside of the gloves is contaminated, and the area inside, next to your skin, is clean. 13. Insert your bare fingers inside the second glove (Figure 2-19J). Remove the glove by pulling it down gently, taking care not to touch the outside of the glove with your bare fingers (Figure 2-19K). It will be wrong side out when removed. Avoid touching your uniform or any other object with the contaminated gloves. 14. Put the contaminated gloves in an infectious waste container immedi- ately after removal (Figure 2-19L). 15. Wash your hands immediately and thoroughly after removing gloves. 18/01/2023 14:29

وزارة التعليم Moustnyor Em.cupon 2022-1444 (J) (A) - (H) (K) (B) (C) (F) (I) (L) FIGURE 2-19 (A) Reach in from the sides to open the inner package and expose the sterile gloves. (B) Pick up the first glove by grasping the glove on the top edge of the folded-down cuff. (C) Hold the glove securely by the cuff and slip the opposite hand into the glove. (D) Slip the gloved fingers under the cuff of the second glove to lift it from the package. (E) Hold the gloved hand under the cuff while inserting the other hand into the glove. (F) Insert the gloved fingers under the cuff, pull out slightly, and turn the cuffs over and up without touching the inside of the gloves or the skin. (G) Interlace the fingers to position the gloves correctly, taking care not to touch the skin with the gloved hands. (H) Use a gloved hand to grasp the other glove by the outside of the cuff. (I) Remove the glove by pulling it down over the hand and turning it inside out. (J) Insert your bare fingers inside the top of the second glove. (K) Pull the glove down gently, taking care not to touch the outside of the glove with your fingers. (L) Place the gloves in an infectious waste container, and wash your hands immediately. checkpoint 1. What must a sterile object never touch? 2. Around a sterile field, how wide of a border is considered contaminated? GE44.PATHWAYS.002.82.HLTH.58.indb 45 INFECTION CONTROL 45 | 18/01/2023 14:29

2:6 MAINTAINING TRANSMISSION- BASED PRECAUTIONS Some diseases are communicable and require isolation. . A communicable disease is caused by a pathogenic organism that can be easily transmitted to others. ⚫ An epidemic occurs when the communicable disease spreads rapidly from person to person and affects a large number of people at the same time. . A pandemic exists when the outbreak of disease occurs over a wide geographic area and affects a high proportion of the population. Transmission-based precautions are a method or technique of caring for patients who have communicable diseases. Examples of Precaution communicable diseases are tuberculosis, wound infections, and pertussis (whooping cough). Transmission-based precautions are used to provide extra protection against specific diseases or pathogens to prevent their spread. Communicable diseases are spread in many ways. Examples include: Direct contact with the patient. Contact with dirty linen, equipment, and/or supplies. ⚫ Contact with blood, body fluids, secretions, and excretions such as urine, feces, and droplets (from sneezing, coughing, or spitting). Discharges from wounds. FIGURE 2-20 Some transmission-based precau- tions require the use of gowns, gloves, and masks, while others require the use of only a mask. Transmission-based precautions are used to limit contact with pathogenic organisms. These techniques help prevent the spread of the dis- ease to other people and protect patients, their families, and health care providers. The type of transmission-based precautions used depends on the causative organism of the disease, the way the organism is transmitted, and whether the pathogen is antibiotic-resistant (not affected by antibiotics). PPE is used to provide protection from the pathogen. Some transmis- sion-based precautions require the use of gowns, gloves, and masks (Figure 2-20), while others require the use of only a mask. 46 CHAPTER 2 وزارة التعليم Missing Educ 2022 1444 GE44 PATHWAYS.G02.82.HLTH.S8.indb 46 18/01/2023 14:29

وزارة التعليم Two terms are extensively used in transmission-based precautions: con- taminated and clean. They refer to the presence of organisms on objects: ⚫ Contaminated, or dirty, means that objects contain disease-produc- ing organisms. These objects must not be touched unless the health care provider is protected by gloves, a gown, and other required items. The outside and waist ties of the gown, protective gloves, and mask are considered contaminated. . Clean means that objects or parts of objects do not contain dis- ease-producing organisms and therefore have minimal chance of spreading the disease. Every effort must be made to prevent contam- ination of these objects or parts of objects. The insides of the gloves and gown are clean, as are the neckband, its ties, and the mask ties. There are four types of contact: standard, airborne, droplet, and contact. Health care facilities must have a list of conditions that shows the type and duration of precautions needed for each specific disease. STANDARD PRECAUTIONS Standard precautions (see Section 2:3) are used for all patients. A patient must be placed in a private room if the patient contaminates the environ- ment or is not able to maintain appropriate hygiene. Health care providers must follow the recommendations for the use of gloves, gowns, and face masks when conditions indicate their use. AIRBORNE PRECAUTIONS Airborne precautions are used for patients known or suspected to be infected with pathogens transmitted by airborne droplets. These are small particles of evaporated droplets that contain microorganisms and remain suspended in the air or on dust particles. Examples of diseases requiring airborne precautions are rubella (german measles), varicella (chickenpox), tuberculosis, coronaviruses (such as COVID-19), and severe acute respira- tory syndrome (SARS). Standard precautions are used at all times. In addition, the following precautions must be taken: The patient must be placed in an airborne-infection isolation room, and the door should be kept closed. . Air in the room must be discharged to the outside or filtered before being circulated to other areas. Ministry of Education 2022-1444 GE44.PATHWAYS.002.82.HLTH.58.indb 47 INFECTION CONTROL 47 | 18/01/2023 14:29

(A) (B) FIGURE 2-21 (A) The N95 respirator mask. (B) The P100 respirator mask. . Each person who enters the room must wear respiratory protection in the form of an N95 (Figure 2-21A), P100 (Figure 2-21B), or more powerful filtering mask such as a HEPA (high-efficiency particulate air) mask. These masks contain special filters to prevent the entrance of small airborne pathogens. Men with facial hair cannot wear a standard filtering mask because a beard prevents an airtight seal and so must use a special HEPA-filtered hood. • If at all possible, the patient should not be moved from the room. If transportation is essential, however, the patient must wear a surgical mask during transportation to minimize the release of droplets into the air. 48 CHAPTER 2 وزارة التعليم Missing or Esco 2022 1444 GE44 PATHWAYS.G02.82.HLTH.58.indb 48 DROPLET PRECAUTIONS Droplet precautions must be followed for a patient known to be, or sus- pected of being, infected with pathogens transmitted by large-particle droplets expelled during coughing, sneezing, talking, or laughing. An example of a disease requiring these isolation precautions is multidrug-re- sistant streptococcal meningitis. Standard precautions are used at all times. In addition, the following precautions must be taken: ⚫ The patient should be placed in a private room. If a private room is not available, and the patient cannot be placed in a room with a patient who has the same infection, a distance of at least 1 meter (3 feet) should separate the infected patient and other patients or visitors. ⚫ Masks must be worn when entering the room. If transportation or movement of the patient is essential, the patient must wear a surgical mask. 18/01/2023 14:29

وزارة التعليم Minisinjor Emicition 2022-1444 CONTACT PRECAUTIONS Contact precautions must be followed for any patients known to be, or suspected of being, infected with epidemiological (capable of spreading rapidly from person to person, an epidemic) microorganisms that can be transmitted by either direct or indirect contact, such as COVID-19. Standard precautions are used at all times. In addition, the following pre- cautions must be taken: The patient should be placed in a private room or, if a private room is not available, in a room with a patient who has an active infection caused by the same organism. ⚫ Gloves must be worn when entering the room. ⚫ Gloves must be changed after having contact with any material that may contain high concentrations of the microorganism, such as wound drainage or fecal material. ⚫ Gloves must be removed before leaving the room, and the hands must be washed with an antimicrobial agent. . A gown must be worn in the room. The gown must be removed before leaving the room, and care must be taken to ensure that clothing is not contaminated after gown removal. Movement and transportation of the patient from the room should be for essential purposes only. The room and items in it must receive daily cleaning and disinfection. If possible, patient-care equipment (bedside commode, stethoscope, sphygmomanometer, thermometer) should be left in the room and used only for this patient. If this is not possible, all equipment must be cleaned and disinfected before being used on another patient. PROTECTIVE OR REVERSE ISOLATION Protective or reverse isolation refers to methods used to protect certain patients from organisms present in the environment. It is used mainly for those whose body defenses are not capable of protecting them from infections and disease. Examples of patients who require this protection are patients who are severely burned, patients receiving chemotherapy or radiation treatments for cancer, or patients whose immune systems have failed. Standard precautions are used at all times. In addition, the following precautions may be taken: The patient is placed in a room that has been cleaned and disinfected. ⚫ The room is disinfected frequently while the patient stays there. GE44.PATHWAYS.002.82.HLTH.58.indb 49 INFECTION CONTROL 49 18/01/2023 14:29

Anyone entering the room must wear clean or sterile gowns, gloves, and masks. ⚫ Equipment or supplies brought into the room are disinfected or sterile. Special filters may be used to purify the air that enters the room. Every effort is made to protect the patient from microorganisms that cause infection or disease. checkpoint 1. What is a communicable disease? 2. When should standard precautions be used? Today's Research Tomorrow's Health Care Paint Away Those Germs? Health care-associated infections are a major problem for health care providers. MRSA is one of the most common health care-associated infections. It is a bacterium that causes severe infections in humans and is difficult to treat because it is resistant to many antibiotics, which means the antibiotics will not eliminate the organism. Now, thanks to biotechnology research, it is possible to use paint to kill MRSA germs. Researchers studied a naturally occurring enzyme, lysostaphin, that is used by nonpathogenic (nondisease-producing) strains of Staphylococcus bacteria to defend themselves against S. aureus. Lysostaphin is harmless to humans and toxic only to MRSA. It is not an antibiotic to which bacteria could become resistant, and it does not leach chemicals into the environment. Lysostaphin kills MRSA bacteria by slicing open the cell wall, causing the MRSA cell to explode and die. One problem encountered during the research was that the lysostaphin was not stable and would not remain in other substances for long periods. The researchers solved this problem by packing the lysostaphin in carbon nanotubes, tiny structures that lock the enzyme in place. The nanotubes containing the enzyme were put in a can of ordinary house paint, which was used to paint a wall. Studies showed that 100% of MRSA organisms were destroyed when they came into contact with the paint. The paint remained effective even after repeated washings. Recently, a microbicidal paint has been created that kills more than 99% of MRSA, Escherichia coli, and vancomycin-resistant Enterococcus faecalis pathogens within 2 hours of exposure on painted surfaces. This initial research could provide many benefits for both health care and other commercial products. By creating coatings containing nanotubes of lysostaphin, commercial products could be developed for walls, furniture, medical equipment, food-processing equipment, and even items such as shoes, masks, or hospital gowns. If this happens, a simple, inexpensive, naturally occurring substance could prevent health care-associated infections, save lives, and decrease medical costs. Case Study Investigation Conclusion What PPE would allow Fahad and Ayisha to work safely in the emergency department during the COVID-19 pandemic? As health care team members became ill, Fahad and Ayisha had to cross-train in other areas of the hospital, for example, transportation and intensive care. Would these new duties affect the type of PPE and isolation techniques they would need to use? 50 CHAPTER 2 وزارة التعليم Minising or Econ 2022 1444 GE44 PATHWAYS.G02.82.HLTH.S8.indb 50 18/01/2023 14:29