Principles of Asepsis

32 Principles of Asepsis

Learning Outcomes 32.1 Explain the historical background of infectious disease prevention. 32.2 Identify the types of microorganisms that cause disease. 32.3 List some infectious diseases, and identify their signs and symptoms. 32.4 Discuss the importance of preventing antibiotic resistance in a health-care setting. 32.5 Describe ways you can help prevent antibiotic resistance in health-care settings.

Learning Outcomes (cont.) 32.6 Explain the disease process. 32.7 Explain how the body’s defenses protect against infection. 32.8 Describe the cycle of infection. 32.9 Identify and describe the various methods of disease transmission. 32.10 Explain how you can help break the cycle of infection.

Antibiotic-resistant organisms Importance of patient education on the proper use of antibiotics You will learn about: Disease-causing microorganisms How the body fights disease Ways infections occur Introduction Our bodies are amazing structures that defend us against infections under normal circumstances

Throughout history people have attempted to discover Causes of infection How to prevent infections How to treat infections History of Infectious Disease Prevention

History of Infectious Disease Prevention (cont.)

History of Infectious Disease Prevention (cont.) • Remarkable advances in the past century • Threat of infection still present • New infectious diseases • AIDS • Ebola • Resistant diseases • MRSA • VRSA • Multidrug-resistant TB

Apply Your Knowledge Why is the threat of infection still present even though great advances have been made in controlling infections over the past century? ANSWER: The threat of infection is still present because of new diseases and diseases that have become resistant to treatments. Right!

Microorganisms and Disease • Microorganisms live all around us • Pathogens • Microorganisms capable of causing disease • Evade host defenses • People avoid infections most of the time • Many microorganisms are beneficial or harmless • Normal defenses resist infection • Conditions are not favorable for pathogens to grow and be transmitted

Microorganisms and Disease (cont.) * Experts disagree as to whether prions are directly responsible for disease or merely aid an unknown agent in causing disease.

Microorganisms and Disease (cont.)

Apply Your Knowledge In many cases, we avoid contracting infections when exposed to microorganisms. What are the reasons for this? ANSWER: This is because: • many microorganisms are beneficial or harmless • we have normal defenses to resist infection • conditions are not favorable for the pathogen to grow and be transmitted. Correct!

Knowing signs and symptoms of common infectious diseases can help protect against exposure Infectious Diseases

Infectious Diseases (cont.)

Office measures Use negative pressure area Use personal respirator Apply standard sanitization, disinfection, and sterilization techniques Preventing the Spread of TB • Containment of the tuberculosis bacteria • Patient measures • Covering mouth • Proper disposal of tissues • Take medication as directed • Avoid close contact with others • Air out their room

Apply Your Knowledge How can the spread of many infectious diseases can be limited or prevented? • ANSWER: The spread of many infectious diseases can be limited or prevented by using commonsense precautions: • Using tissues when coughing or sneezing • Washing hands frequently • Using disposable dishware Excellent!

Drug-Resistant Microorganisms • MRSA – methicillin/oxacillin-resistant S. aureus • VRE – vancomycin-resistant enterococci • VISA – vancomycin-intermediate S. aureus • VRSA – vancomycin-resistant S. aureus • ESBLS – extended-spectrum beta-lactamases • PRSP – penicillin-resistant Streptococcus pneumoniae

Drug-Resistant Microorganisms (cont.) • MRSA and VRE • Most common in non-hospital health-care facilities • Community-associated MRSA • Increasing in incidence • PRSP • Common in patients seeking care in physicians’ offices and clinics (pediatrics)

Drug-Resistant Microorganisms (cont.) • Risk factors for development of infections by drug-resistant organisms • Advanced age • Invasive procedures • Prior use of antibiotics • Repeated contact with health-care system • Severity of illness • Underlying diseases or conditions

Preventing Antibiotic Resistance • Four strategies to reduce incidence of antibiotic-resistant microorganisms • Prevent infection • Diagnose and treat infection appropriately • Use antibiotics carefully • Prevent transmission of infections

Good Job! Apply Your Knowledge What strategies reduce the incidence of antibiotic-resistant microorganisms? • ANSWER: Strategies to reduce the incidence of antibiotic-resistant microorganisms include: • Prevent infections • Diagnose and treat infections appropriately • Use antibiotics carefully • Prevent transmission

Begins with microorganisms finding host Grows with specific requirements Proper temperature pH Moisture level Virulence – microorganism’s disease-producing power Damage is caused by: Depleting nutrients Reproducing themselves Making body cells the target of body’s own defenses Producing toxins Disease Process

Disease Process (cont.) • Once exposed to a pathogen, the body goes through 4 stages of illness: • Incubation – begins at first exposure; ends when first symptom appears • Prodromal – begins at first onset of symptoms; generally short • Invasion – numbers of organisms are greatest; symptoms are most pronounced • Convalescent – patient regains normal health status

Apply Your Knowledge What are the four stages of illness? • ANSWER: The four stages of illness are: • Incubation – begins at first exposure; ends when first symptom appears • Prodromal – begins at first onset of symptoms; generally short • Invasion – numbers of organisms are greatest; symptoms are most pronounced • Convalescent – patient regains normal health status SUPER!

Immunity – condition of being resistant to pathogens and the disease they cause First lines of defense Skin Sweat glands Mucous membranes Cilia Lacrimal glands Saliva Hydrochloric acid Lysozyme The Body’s Defenses

The Body’s Defenses (cont.) • Resident normal flora – microorganisms found in the body • Provide a barrier against pathogens • Normally live in balance • Become pathogenic when host’s defenses are compromised • Opportunistic infections • Infections occurring when a host’s resistance is low

Inflammation Signs Redness Localized heat Swelling Pain Purpose Summon immunologic agents to site Begin tissue repair Destroy invading microorganisms Nonspecific Defenses

Nonspecific Defenses (cont.) • Steps of inflammation • Initial constriction, then dilation of blood vessels, causing redness and heat • Fluid leakage from local vessels  swelling • Scar tissue formation • Chronic inflammation • Damage to tissues • Loss of function

Principles of Asepsis