Infection Control Flashcards
(44 cards)
Types of Infection
Pathogenic microorganisms cause infection and disease in different ways. Some pathogens produce poisons called toxins, which harm the body. An example is the bacillus that causes tetanus, which produces toxins that damage the central nervous system. Some pathogens cause an allergic reaction in the body, resulting in a runny nose, watery eyes, and sneezing. Other pathogens attack and destroy the living cells they invade. An example is the protozoan that causes malaria; it invades red blood cells and causes them to rupture. Infections and diseases are also classified as endogenous, exogenous, healthcare-associated, or opportunistic.
Endogenous
Means the infection or disease originates within the body. These include metabolic disorders, congenital abnormalities, tumors, and infections caused by microorganisms within the body.
Exogenous
Means the infection or disease originates outside the body. Examples include pathogenic organisms that invade the body, radiation, chemical agents, electric shock, and temperature extremes.
HAI
Health care-associated infection, formerly referred to as nosocomial or hospital-acquired, is an infection acquired by an individual and a healthcare facility such as a hospital or long-term care facility. Healthcare associated infections are usually present in the facility and transmitted by healthcare team members to the patient. Many of the pathogens transmitted in this manner are antibiotic resistant and can cause serious and even life-threatening infections in patients. Common examples are staphylococcus, pseudomonas, and enterococci. Infection control programs are used in healthcare facilities to prevent and deal with HAIs. The infection control professionals that run these programs are called infection preventionists, according to the Association for Professionals in Infection Control and Epidemiology (APIC). Their job is to reduce the incidence of HAIs.
Opportunistic infections
Infections that occur when the body’s defenses are weak. These diseases do not usually occur in individuals with intact immune systems. Examples include the development of a yeast infection called candidiasis, Kaposi’s sarcoma (a rare type of cancer), or Pneumocystis carinii pneumonia in individuals who have AIDS.
Vaccines
Vaccines are used whenever available 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 weak or dead germs that can cause diseases. After getting vaccinated, an individual develops immunity to that disease without having to get the disease first. Vaccinations protect both the individual getting them and the community 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 can’t travel as easily from person to person and the entire Community is less likely to get the disease. This idea is called community immunity.
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.
- Healthcare providers must constantly be aware of the parts in the chain of infection. If any part of the chain is eliminated, the spread of disease or infection will be stopped. A healthcare provider who is aware of this can follow practices to interrupt or break this chain and prevent the transmission of disease. It is important to remember that pathogens are everywhere in that preventing their transmission is a continuous process.
Infectious agent
A pathogen, such as a bacterium or virus that can cause a disease. This part of the chain of Infection can be prevented by rapid, accurate identification of organisms.
Reservoir
- An area where the Infectious agent can live. Some common reservoirs include the human body, animals, the environment, and fomites, or objects contaminated with infectious material that contains the pathogens. Common fomites include doorknobs, bed pans, urinals, linens, instruments, and specimen containers.
- this part of the chain of Infection can be broken by cleaning and sterilizing a blood covered instrument or spraying to destroy mosquitoes.
Portal of exit
- A way for the Infectious agent to escape from the reservoir in which it has been growing. In the human body, pathogens can leave the body through urine, feces, saliva, blood, tears, mucus discharge, sexual secretions, and draining wounds.
- this part of the chain of infection can be prevented with thorough washing of the hands and intact, unbroken skin
Mode of transmission
- a way that the Infectious agent can be transmitted to another reservoir or host where it can live. The pathogen can be transmitted in different ways. One way is by direct contact, which includes person to person contact (physical or sexual contact) or contact with a body secretion containing the pathogen. Contaminated hands are one of the most common sources of direct contact transmission. Another way is by indirect contact, when the pathogen is transmitted from contaminated substances such as food, air, soil, insects, feces, clothing, instruments, and equipment. Examples include touching contaminated equipment and spreading the pathogen on the hands, breathing in droplets carrying airborne infections, and contacting vectors (insects, rodents, or small animals), such as being bitten by an insect carrying a pathogen.
- a way to eliminate this part of the chain of infection includes thorough washing of the hands, cleaning and sterilizing a blood covered instrument and spraying to destroy mosquitoes.
Portal of entry
- a way for the Infectious agent to enter a new reservoir or host. Some ways pathogens can enter the body are through breaks in the skin, breaks in the mucous membrane, the respiratory tract, the digestive tract, the genitourinary tract, and the circulatory system. If the defense mechanisms of the body are intact and the immune system is functioning, a human can frequently fight off the Infectious agent and not contract the disease. Body defenses include: mucous membrane, cilia, coughing and sneezing, hydrochloric acid, tears in the eye, fever, inflammation, and immune response
Susceptible host
A person likely to get an infection or disease, usually because body defenses are weak.
Aseptic Techniques
- A major way to break the chain of infection is to use aseptic techniques while providing healthcare. Asepsis is defined as the absence of disease producing microorganisms, or pathogens.
- sterile means free from all organisms, both pathogenic and non-pathogenic, 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 are directed toward maintaining cleanliness and eliminating or preventing contamination. Common aseptic techniques include hand washing, good personal hygiene, use of disposable gloves when contacting body secretions or contaminated objects. Proper cleaning of instruments and equipment, and thorough cleaning of the environment.
- various levels of aseptic control are possible. These include antisepsis, disinfection, and sterilization. It is important for the healthcare provider to know and use these methods in every aspect of providing Healthcare to prevent the spread and transmission of disease.
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 include alcohol and Betadine.
Disinfection
This is a process that uses chemical disinfectants to destroy or kill pathogenic organisms. It is 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 zephirin.
Sterilization
This is a process that 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 autoclave is the most common piece of equipment used for sterilization.
Bioterrorism
The use of microorganisms, or biologic agents, as a weapons to infect humans, animals, or plants. Throughout history, microorganisms have been used in biologic warfare..
Biologic agents
Many different microorganisms can cause diseases in humans, animals, and plants. However, only a limited number are considered to be ideal for bioterrorism. Six characteristics of the “ideal” microorganisms include:
- inexpensive and readily available or easy to produce
- spread through the air by winds or ventilation systems and inhaled into the lungs of potential victims, or spread by ingesting contaminated food or water.
- survives sunlight, drying, and heat
- causes death or severe disability and public panic
- easily transmitted from person to person
- difficult to prevent or has no effective treatment
High-Priority Bioterrorism Agents
The Centers for Disease Control and Prevention (CDC) has identified and classified major bioterrorism agents. High priority agents that have been identified include:
-smallpox: a highly contagious infectious disease that is caused by a variola virus. Vaccinations against this were no longer required after many years with no reported cases.
- anthrax: an infectious disease caused by the spores of bacteria called Bacillus anthracis. The spores are highly resistant to destruction and can live in soil for years. Grazing animals such as cattle, sheep, and goats eat the contaminated soil and become infected. Humans develop anthrax by exposure through the skin (cutaneous), by eating undercooked or raw infected meat (gastrointestinal), or by inhaling the spores (pulmonary). Cutaneous and gastrointestinal anthrax are usually treated successfully with antibiotics, but some victims die. Inhalation anthrax causes death in more than 80% of its victims. In anthrax vaccine is available for prevention, and the military has an active vaccination program.
- plague: an infectious disease caused by bacteria called Yersinia pestis. Usually plague is transmitted by the bites of infected fleas. In some cases, the organism enters the body through a break in the skin or by contact with the tissue of an infected animal (bubonic plague). Rats, Rock squirrels, prairie dogs, and Chipmunks are the most common sources of plague in the United states. If the disease is not treated immediately with antibiotics, the infection spreads to the blood and lungs, and causes death. No vaccine for plague is available in the United States.
- Botulism: a paralytic illness caused by a nerve toxin produced by bacteria called Clostridium botulinum. Three main types of botulism exist. one type is caused by eating foods that contain the toxin. A second type is caused by the presence of the toxin in a wound or injury to the skin. A third type occurs in infants who eat the spores that then grow in the intestine and release the toxin. The toxin rapidly causes muscle paralysis. If it is not treated with an antitoxin, the paralysis spreads to the respiratory muscles and causes death.
- Hemorrhagic fever: an infectious disease caused by a filovirus. Two filoviruses have been identified: the Ebola virus and the Marburg virus. The source of these viruses is still being researched, but the common belief is that the viruses are transmitted from animals such as bats, monkeys, and chimpanzees. Once the viruses affect a human, the disease is spread rapidly from person to person by contact with body fluids. Treatment is supportive care with fluid and electrolyte replacement, respiratory support, and management of symptoms.
Preparing for Bioterrorism
A bioterrorism attack could cause an epidemic and a public health emergency. Large numbers of infected people would place a major stress on Healthcare facilities. Fear and panic could lead to riots, Social disorder, and disregard for authority. For these reasons, the Bioterrorism Act of 2002 was passed by Congress and signed into law in June 2002. This act requires the development of a comprehensive plan against bioterrorism to increase the security of the United states. Preparing for bioterrorism will involve government at all levels including local regional, state, and national. Some of the major aspects of preparation include:
- community-based surveillance to detect early indications of a bioterrorism attack
- notification of the public when a high risk situation is detected
- strict infection control measures and public education about the measures
- funding for studying pathogenic organisms, developing vaccines, researching treatments, and determining preventive actions.
- strict guidelines and restrictions for purchasing and transporting pathologic microorganisms
- Mass immunization, especially for military, first responders, police, fire department, and healthcare personnel
- increased protection of food and water supplies
- training personnel to properly diagnose and treat infectious diseases
- establishing emergency Management policies
- criminal investigation of possible threats
- improving the ability of healthcare facilities to deal with an attack by increasing emergency department space, preparing decontamination areas, and establishing isolation facilities
- improving communications so information about bioterrorism is transmitted quickly and efficiently
Every healthcare provider must constantly be alert to the threat of bioterrorism. In today’s world, it is likely that an attack will occur. Careful preparation and thorough training can limit the effect of the attack and save the lives of many people.
Washing Hands
Hand washing is a basic task required in any Healthcare occupation. An aseptic technique is a method followed to prevent the spread of germs or pathogens. Hand washing is the single most important method used to practice aseptic technique. Hand washing is also the most effective way to prevent the spread of infection. The hands are a perfect medium for the spread of pathogens. Thoroughly washing the hands helps prevent and control the spread of pathogens from one person to another. It also helps protect the healthcare provider from disease and illness.
Regular Hand washing
The CDC publishes the results of hand washing research and provides recommendations for hand hygiene. The recommendations call for regular hand washing using plain soap and water for routine cleansing of the hands when the hands are visibly dirty or soiled with blood or other body fluids.
Antiseptic Hand Washing
Antiseptic hand washing uses an antimicrobial soap and water. The CDC recommends antiseptic handwashing before invasive procedures, in critical care units, while caring for patients on specific organism transmission based precautions, and in specific circumstances defined by the infection control program of the healthcare facility.