Understanding and Managing Communicable and Infectious Diseases PDF

IMMUNOLOGY UNDERSTANDING AND MANAGING COMMUNICABLE AND INFECTIOUS DISEASES 1ST SEMESTER | SY. 2024-2025 | PROF. MARLO N. BOBIER| NOVEMBER 16, 2024 THE INFECTION PROCESS through a break on the s...

IMMUNOLOGY UNDERSTANDING AND MANAGING COMMUNICABLE AND INFECTIOUS DISEASES 1ST SEMESTER | SY. 2024-2025 | PROF. MARLO N. BOBIER| NOVEMBER 16, 2024 THE INFECTION PROCESS through a break on the skin or mucous Infection membranes → The entry and multiplication of an infectious agent → All contagious diseases are considered infectious in or on the tissue of a host. Isolation Cell or Tissue Colonization → The separation of an individual suffering from a → the agent fails to cause injury to the host’s cells or communicable disease from other people. tissue Quarantine Symptomatic → Refers to the limitation of the freedom of → the pathogens multiply and cause clinical signs movement imposed on people or animals and symptoms previously exposed to communicable disease/s for Communicable a period of time equivalent to the longest → If the infectious disease can be transmitted directly incubation period of that particular disease. or indirectly from one person to another; it is Reservoir referred to as an infectious disease → It may be one or more species of plant or animal Infectious Disease in which an infectious agent lives and multiplies for → An organism damages or alters the host’s its survival, as well as a venue to reproduce itself physiology in such a manner that it can be transmitted to Pathogens humans → Organisms that have the ability to cause a disease Surveillance Nonpathogenic Organisms → The act of watching, collecting, and recording data → Organisms that do not cause disease from a particular population or area. Virulence → A measure of the likelihood that a particular A WHY DOES INFECTION OCCUR? organism will cause a disease Some bacteria develop resistance to antibiotics. Some viruses such as influenza have so many different strains that a single vaccine cannot protect against them all. COMMON TERMS RELATED TO INFECTION Most viruses resist antiviral drugs. Carrier New infectious agents occasionally arise, such as HIV and → An individual who harbors the organism and is coronaviruses. capable of transmitting it to susceptible host Some microbes localize in areas of the body that make → Often asymptomatic (they do not show treatment difficult (bones, central nervous system) manifestations of the disease) Opportunistic organisms can cause infection in Communicable Disease immunocompromised patients. → An illness caused by an infectious agent or its toxic Some people have not received immunization. products The increase in air travel can spread virulent organisms to → May be transmitted directly or indirectly to a a heavily populated area within hours and over great healthy person through an agent, a vector, or an distances inanimate object The use of biological warfare and bioterrorism with organisms such as the causative agents of anthrax and Contact plague is increasingly becoming a threat to public health → Any person or animal who had been in close and safety throughout the world. association with an infected person, animal, or The use of immunosuppressive drugs and invasive freshly soiled materials. procedures increases the risk of infection among the Contagious Disease populace, especially in the very young and older adults. → Easily transmitted from one person to another through direct or indirect means. B FOUR STAGES OF INFECTIOUS DISEASE Disinfection → Destruction of pathogenic microorganisms outside 1. Incubation Period The time between the body using direct physical or chemical means exposure to a a. Concurrent disinfection pathogen and when → is done immediately after the symptoms and/or signs first become infected individual produces apparent. infectious material/secretions Signifies the length of → it is carried out when the patient time it takes for the is still the source of infection. organism to multiply b. Terminal disinfection and reach a → is applied when the patient is no population necessary longer the source of infection to produce symptoms → it is carried out either when the in the host. client has died or has been 2. Prodromal Period Occurs between end of discharged – everything that the incubation period and had been used by the client are the point at which characteristic symptoms disinfected, including the room of the illness appear. that client occupied. 3. Period of Clinical Illness Phase of rapid Habitat multiplication of the → Place where an organism is usually found pathogen with exponential Host growth and peak in its → A person, animal, or plant which a parasite population. depends on for its survival. 4. Convalescence Period The time the host recovers Infectious Disease gradually and returns to → It is transmitted not only by ordinary contact but baseline. also requires direct inoculation of the organism  3. Exogenous Infection “exo” means outside Due to a microorganism entering the host’s body from the environment. 4. Endogenous Infection Results from the host’s normal flora such as in the case of host’s own bacteria. 5. Health-care Formerly known as associated infections “nosocomial (HAIs) infections Develop while the patient is in a health care facility HAIs are mostly transmitted through direct contact SPECIFIC AND GENERAL APPROACHES TO E STANDARD PRECAUTIONS C INFECTION PREVENTION AND CONTROL – 1. Barrier Precautions WORLD HEALTH ORGANIZATION (WHO) → Correct use of PPE or universal barriers 1. A scientific approach and practical solution designed to 2. Precautions for Invasive Procedures prevent harm caused by infection to patients and health 3. Workplace Precautions workers. 2. Infection prevention and control practices are important in → Prevent needle injuries; dispose of needles, maintaining a safe environment for patients by reducing the syringes and other sharps in puncture-proof risk of the potential spread of disease from person to containers. person. 3. Recommended infection control principles and practices for F TRANSMISSION-BASED PRECAUTIONS local health agencies: 1. Airborne Precautions a. Practice of standard precautions → Require special handling and ventilation b. Implement hand hygiene practices procedure to prevent the spread of infection. → The use of respiratory protection is mandatory 2. Droplet Precautions → It is observed because large particle droplets do not remain in the air and generally travel short distances, around three feet or less 3. Contact Precautions → Require the use of gloves, mask, and gown → A thorough handwashing is recommended after removal of protective items WHAT IS A DISEASE? DISEASE A mechanism reduces output or activity to return an organ or system to its normal range of functioning. c. Appropriate use of personal protective equipment SIGNS & SYMPTOMS OF A DISEASE (PPE) or universal barriers Signs → Objective and measurable → Can be directly observed by a clinician or a health care worker Symptoms → Subjective d. Precautionary measures against needle stick and → Felt or experienced by the patient, they cannot be sharps injury clinically confirmed or objectively measured e. Regular cleaning and disinfection of working area and supplies used f. Implementation of Proper Waste Disposal SIGNS OR SYMPTOMS? i. Presidential Decree 825 – Imposing LOW BLOOD PRESSURE – Sign penalty for Improper disposal of garbage and other forms of uncleanliness CYANOSIS - Sign ii. Presidential Decree 856 – the Code on Sanitation mandates sanitation for all SHORTNESS OF BREATH - Symptom food establishments and refuse collections and disposal system of cities and municipalities nationwide. A GEOGRAPHICAL DISTRIBUTION OF DISEASES D KINDS OF INFECTION Endemic Diseases Diseases found in a certain geographic area/region or in a 1. Subclinical or A laboratory-verified specific group of people within Asymptomatic infection that presents no the country Infection signs and Ex: Schistosomiasis is symptoms rampant in provinces like 2. Latent Infection Occurs when the Samar and Leyte microorganism remains Epidemic Occur in greater than inactive and expected numbers in a dormant in the host and specific area over a particular may last for years. time  A sudden rise in the number of Nursing management cases more than what is is directed toward expected preventing of Ex: an increased number of complications, diarrheal diseases in an deterioration, and evacuation area permanent disability. Pandemic An epidemic that affects several countries or 10 STRATEGIES FOR INFECTION PREVENTION & continents CONTROL Ex: HIV/AIDS 1. Hand Hygiene Sporadic Diseases Occur occasionally and 2. Environmental Hygiene irregularly with no specific 3. Screening and cohorting patients pattern 4. Vaccinations Usually involve few people 5. Surveillance during a particular time 6. Antibiotic Stewardship Ex: Tetanus, gas gangrene 7. Care coordination 8. Following the evidence B THE NURSE & COMMUNICABLE DISEASE 9. Institutional culture As a member of the health team, a professional nurse 10. Comprehensive Unit-based Safety Programs should be knowledgeable of the following: 1. The nature of the specific microorganism and its C CARE FOR PATIENTS WITH COMMUNICABLE capacity for survival, both within or outside the DISEASE body. 1. Self-protection by increasing resistance, use of 2. The most effective method to eliminate the specific protective clothing and/or repellents organism. 2. Preventing the spread of the infectious agent through 3. How the organism invades the host and its exit medical asepsis and concurrent disinfection routes from the body. 3. Physical care through personal hygiene, sufficient 4. The incubation periods, prodromata, the length of sleep and rest communicability of the disease. 4. Emotional support 5. How specific drug/s alter the clinical signs and the 5. Spiritual aspects of care infectious course of the disease. 6. The most recent methods and concepts of What is the single most effective way to protect prophylaxis for communicable disease. clients from infection? 7. The control measures and rationales, including isolation techniques. Handwashing or using a hand antiseptic 8. Identify and carry out all Levels of Prevention. EPIDEMIOLOGICAL TRIAD LEVELS OF PREVENTION Disease is the result of all agent forces within the dynamic a. Primary Prevention Involves developing system consisting of the following: strategies by evading a. Agent disease risk factors b. Host and avoiding c. Environment unhealthy behaviors Applied to clients who are physically and emotionally healthy Precedes a disease or dysfunction It is considered “true prevention” because the problem has not yet occurred b. Secondary Prevention Seeks to identify people at risk of contracting various INFECTIOUS AGENTS illnesses by The microorganisms or pathogens that cause infection. conducting tests and Factors influencing the cause of the disease: routine check-ups to → Pathogenicity prevent onset of the → Infectivity disease → Virulence Focuses on the → Infective dose individual who are expecting health A FACTORS INFLUENCING THE CAUSE OF THE problems or illness DISEASE: Protects those who Pathogenicity are at risk for → refers to the ability of an organism to cause developing disease. This ability represents a genetic complications or component of the pathogen and the overt damage worsening conditions done to the host Geared towards early Infectivity diagnosis and → the ability of the organism to infect the host treatment Virulence c. Tertiary Prevention Aims to manage the → the ability of the organism to produce disease. The illness to prevent virulence of a microorganism is a measure of the further deterioration severity of the disease it causes of health status Infective dose Occurs when a → the number of organisms and the amount of toxin disability is released by the organism needed to induce a permanent or disease irreversible  B HOST Each link in the chain must be favorable to the organism in The host factor influences an individual’s exposure, order to cause a disease. susceptibility, or response to causative agent. Breaking any link can disrupt its multiplication, thereby → Patient interrupting the occurrence of infection. → Carrier → Suspect 1. INFECTIOUS AGENTS → Contact Microbes capable of producing a disease Patient A person who is infected The number of organism affect their ability to cause a and manifests the signs disease, as well as the susceptibility of the host and symptoms of the For the organisms to cause a disease they must be able to: disease → Adhere the skin and the mucous membranes; Carrier A person who → penetrate the skin or mucous membranes; and appears healthy but → multiply and invade the body's natural defenses harbors the organism Capable of 2. RESERVOIR OF INFECTION transmitting the Can be a person, animal, plant, the soil, or other substances disease but does not where an infectious agent lives and multiplies until it can manifest its signs and infect a susceptible host. symptoms 3 Categories of Reservoirs: Suspect A person whose medical → Human Reservoir history, signs, and → Animal Reservoir symptoms suggest that → Environmental Reservoir such a person is suffering from that particular A. Human Reservoir disease I. Frank cases or very ill individuals Contact A person who has been in II. Sub-clinical or ambulatory close association with an III. Carriers infected person, animal, or → The incubatory carrier is one who can transmit object the pathogen during the incubation period prior to a clinical illness. C ENVIRONMENT → A convalescent carrier is a client who is Sum total of all external conditions that affects the recovering from the illness but continues to shed development of an organism and serves as an opportunity the pathogenic organism. of the host’s exposure to harmful microorganisms. → An intermittent carrier is a person who Components of Environment occasionally sheds the pathogenic organism → Physical Environment → A chronic or sustained carrier perpetually → Biological Environment harbors the infectious organism in his/her system. → Socio-economic Environment B. Animal Reservoir COMPONENTS OF ENVIRONMENT Includes domesticated and wild animals infected by Physical Environment Composed of the pathogens. inanimate surroundings, such as the geophysical C. Environmental Reservoir condition and the climate that could be deterrent or Refer to living and non-living reservoirs that harbor favorable for the infectious pathogens outside the bodies of animals. multiplication of microorganisms 3. PORTAL OF EXIT Biological Environment Comprises the living The route in which the organism leaves the reservoir things around the affected Common portals of exit: individual or population, a. Respiratory Tract - nasal discharges such as plants and animal b. Genitourinary Tract (GUT) - urethral secretions life. Gastrointestinal Tract (GIT) - vomitus, stools, some Socio-economic The level of economic anal secretions Environment development of the c. The skin and mucous membrane - skin infections community and factors d. The placenta (in vertical transmission) such as crowding, sanitation, and availability 4. MODE OF TRANSMISSION of health services. The means by which the infectious agent passes from the portal of exit from the reservoir to the susceptible host THE CHAIN OF INFECTION The easiest link to break in the chain of infection Transmission of infection occurs when the agent leaves the reservoir or host through a portal of exit and is conveyed A. Contact Transmission by the mode of transmission and enters through an the most common mode of transmission. appropriate portal of entry to infect the susceptible host. This is divided into: I. Direct Contact → refers to person-to-person transfer of organisms II. Indirect Contact → contact occurs when the susceptible person comes in contact with a contaminated object. → Droplet Spread ▪ contact with respiratory secretions produced when the infected person coughs, sneezes, or talks. Microbes carried in droplets can travel up to three feet, or one meter.  ▪ The organism is not suspended causing in the air but settles on a organisms or surface. substances → Airborne Transmission ▪ transmission occurs when fine B. DIFFERENT TYPES OF LEUKOCYTES aerosolized droplets or dust particles containing microbes a. Neutrophils Primarily attack bacteria; They rush to remain suspended in the air for the site of proliferating bacteria to fight a prolonged period and is them, but are easily killed; the bone subsequently spread by air marrow produces more every day. currents and inhaled by other Some bacteria avoid neutrophils by people. hiding inside cells. → Vehicle Transmission b. T helper cells cells give instructions to other cells by ▪ transmission refers to the producing signals. Each T helper cell transmission of pathogens only looks out for one type of through water, food, and air pathogen. Many T helper cells are → Vector-borne Transmission needed to watch for many different ▪ occurs when intermediate diseases or invaders carriers, such as fleas, flies, c. Cytotoxic T are killer cells that punch holes in the mosquitoes, transfer the cells walls of the pathogenic cells so that the microbes to another living contents ooze out organism d. Macrophages ingest or clean up the mess of dead cells. Its name means 'big eater’ B. Vertical Transmission e. Dendritic cells act like spies. They monitor for the passage of a disease-causing agent (pathogen) from pathogens and present the evidence to the mother to her baby during the period immediately before T cells in the lymph nodes and after birth. f. B cells cells produce antibodies, which lock This transmission might occur across the placenta, in the onto the antigen of invading bacteria breast milk, or through direct contact during or after birth. and immobilize them until the → Example: HIV can be a vertically transmitted pathogen. macrophages consume them. Some B cells become memory cells after being 5. PORTAL OF ENTRY activated by the presence of an The venue where the organism infiltrates the susceptible antigen. These cells live for a long time host and can respond quickly following a It is the same avenue used by the infective microbes when second exposure to the same antigen they exit from the reservoir g. Suppressor T slow down the immune response once Controlling the portal of entry involves maintaining the cells the infection has been eliminated to integrity of the protective tissues of the host prevent damage to normal cells. A. BODY DEFENSES C. ILLNESS FOLLOWING THE ENTRANCE OF A First Line of Defense (External Defense System) ORGANISM INTO THE BODY DEPENDS ON: Second Line of Defense 1. age, sex, genetic, constitution of the host; MODE OF TRANSMISSION 2. nutritional status, fitness, environmental factors; a. First Line of Includes physical and chemical 3. general condition; physical, emotional, mental state; Defense (External barriers that are always present to 4. absence of or abnormal immunoglobulin; Defense System) defend the body from infection 5. presence of underlying diseases (diabetes mellitus, o Skin lymphoma, leukemia, neoplasm, or uremia); and 6. the health status of patients treated with certain → acts as a barrier antimicrobials, corticosteroids, irradiation, or between immunosuppressive drugs. pathogens and the body; skin EMERGING AND RE-EMERGING INFECTIOUS forms a DISEASES waterproof mechanical shield. A EMERGING INFECTIOUS DISEASES o Tears, Mucus, Saliva Those that have recently appeared within a population or → contain an whose incidence or geographic range is rapidly increasing enzyme that or threatens to increase in the near future breaks down Emerging infections can be caused by: the cell walls of → previously undetected or unknown infectious many agents microorganisms → known agents that have spread to new geographic Pathogenic microorganisms must locations or new populations pass through this first line of → previously known agents whose role in specific defense for infection to occur. diseases has previously gone unrecognized If the pathogens manage to gain entry, the second line of defense B RE-EMERGING INFECTIOUS DISEASES within the body is activated. Re-emergence of agents whose incidence of disease had b. Second Line of Activated with the presence of significantly declined in the past, but has since reappeared. Defense injury or multiplying pathogens o Immune Response CONTRIBUTING FACTORS IN THE EMERGENCE AND → A sequence of RESURGENCE OF INFECTIOUS DISEASES IN THE steps where the PHILIPPINES: immune system Demographic factors like the population distribution and attacks density pathogens International travel/tourism & increased OFWs o White Blood Cells Socio-economic factors (Leukocytes) Environmental factors → Cells that seek out and destroy disease-  INFECTION PREVENTION AND CONTROL (IPC) → ways and means to prevent contamination of food A scientific approach and a practical solution designed to and water supply prevent harm caused by infections to both patients and 2. Immunization health workers. The introduction of specific protective antibodies to a susceptible person or animal, or the production of A GENERAL cellular immunity in such a person or animal. Universal Precautions → Shall be observed to prevent contact with blood and other potentially infectious materials. → All patients shall be assumed to be infectious with HIV/AIDS and other bloodborne pathogens Suggested Control Measures → Emphasizes the use of barrier apparel, personal hygiene, and cleaning the environment in addition to universal precautions. B UNIVERSAL PRECAUTIONS 1. Use of Masks → All staff members should wear a mask → Patients should be asked to wear a mask if they have respiratory problems 2. Handwashing → The single most important part of infection control → Practice proper handwashing using of soap and water → Alcohol hand gels and rubs are a practical alternative to handwashing with soap, but dirty or contaminated hands must be washed with soap and water → Nails should be kept short, rings should not be worn 3. Gloving → Gloves are used for all direct patient contact → Change gloves in between patients and wash hands after degloving 4. Gowning → Gowns are used during procedures that are likely to generate splashes or sprays of blood and body fluids, secretions, or excretions 5. Eye protection (goggles) → Goggles are used for aerosol/splash-generating procedures → Avoid getting aerosols 6. Environmental disinfection 3. Immunity → Clean surfaces daily with disinfectant (diluted The ability of an individual to resist disease, either household bleach, 70% alcohol through the activities of specialized body cells or antibodies produced within the body in response to TIPS TO DO PROPER HANDWASHING natural exposure or by the injection of antiserum. Types of Immunity → Natural or Inherent → Artificially acquired → Sub-clinical Immunity 1. Natural or Inherent a. Passive → Acquired through placental transfer; immunity that is acquired by a fetus when it receives maternal antibodies in utero b. Active → Acquired in response to the entry of a live pathogen into the body (such as after recovery from a viral disease) 2. Artificially Acquired a. Passive ASPECTS OF CARE OF PATIENTS WITH → Acquired through the administration of antitoxin, COMMUNICABLE DISEASES antiserum, convalescent serum, and gammaglobulins A PREVENTIVE ASPECT b. Active 1. Health Education → Acquired through the administration of vaccine and toxoid Educate the client and family about the: → availability and importance of prophylactic 3. Sub-clinical Immunity immunization → manner in which infectious illness are spread and Acquired through constant exposure to a particular disease methods to avoid contracting infections or organism to seek medical advice at the first signs of health problems TYPES OF ANTIGENS → importance of environmental cleanliness and INACTIVATED ATTENUATED personal hygiene Killed organism Live/weakened organism Multiple doses are needed only single dose is needed  Booster dose is needed 5. Enteric Isolation The immunity conferred It confers long lasting → The patient has a type of microorganism that can by this type does not long immunity be spread to others directly or indirectly through All vaccines lose their potency after a certain time. The contact with clothing, hands, surfaces, or objects expiry date should be noted on the label or printed on the that are contaminated with microorganisms that vaccine. are still alive, specifically from GIT secretions or excretions. B CONTROL SYSTEM 6. Drainage/secretions Precaution Infectious disease control is one of the important → Aims to prevent infections that are transmitted by components of patient care which can assist in reducing direct or indirect contact with purulent materials or morbidity and mortality. drainage from the affected body site. Isolation and Quarantine 7. Universal Precaution o Source isolation → Refers to blood and body fluid precautions → is described as one of the strategies used to prevent the spread of contagious and B PATHOGENESIS OF INFECTIOUS DISEASES infectious diseases. Use isolated rooms 1. Entry of the pathogen into the body for patients with known or suspected 2. Attachment of pathogen to some tissues within the cases of disease that can spread through body the air, droplets, or contact with others 3. Multiplication of the pathogen o Disinfection (concurrent and terminal) 4. Invasion/spread of the pathogen o Disinfestation 5. Evasion of host defenses → the killing of undesirable small animals by physical or chemical means. o Fumigation/disinfectant fogging → the application of gaseous agent to kill or drive away organisms and insects, respectively. C CURATIVE ASPECT A. Medical management (carried out by physicians) Request/orders for laboratory Treatment of specific diseases Diagnosis B. Nursing management Independent nursing function o any aspect of Dependent nursing actions Collaborative (Interdependent nursing interventions) D REHABILITATIVE ASPECT Activity → Set of restorative or rehabilitative actions that the patient can undertake after discharge from a health care facility Nutrition → Refers to the appropriate diet of the client once they are discharged from the hospital or health care agency MEANS OF CONTROLLING THE SPREAD OF COMMUNICABLE DISEASES 1. Eliminate the source of infection 2. Interrupting the transmission 3. Protecting the susceptible host ISOLATION The practice of separating a patient with a communicable disease from other people to prevent or reduce the transmission of infectious agents, whether directly or indirectly. Purposes of Isolation → To confine the infectious agent to a circumscribed area → To prevent its escape from said area A 7 CATEGORIES RECOMMENDED IN ISOLATION 1. Strict Isolation → Used to prevent the spread of highly contagious or virulent infections 2. Contact Isolation → Separation of the patient to prevent the spread of diseases that can be transmitted through direct contact with open wounds or contaminated articles 3. Respiratory Isolation → Prevents transmission of infectious diseases over short distances through air or droplets 4. Tuberculosis (TB) Isolation → Carried out for TB patients with positive smear or chest x-ray that strongly suggests active TB, both pulmonary and extrapulmonary