Adhere to Infection Control Policies and Procedures UNCLASSIFIED//REL TO NATO/ISAF
Fundamentals of Microbiology • HIV/AIDS, combined with the increasing incidence of hepatitis B, and the continued presence of other infectious diseases such as herpes, has heightened concern in the dental community and made infection control very important.
Fundamentals of Microbiology • Microbiology is the study of small life forms, so small, that they can not be seen with the naked eye. • Includes: • Bacteria, • Special fungi called molds and yeasts, and • Viruses.
Fundamentals of Microbiology • Beneficial Activities • Making bread dough rise • Making yogurt, sour cream and cheese • Synthesizing special agents such as insulin, hepatitis vaccine and other hormones used to treat or prevent diseases
Fundamentals of Microbiology • Harmful Activities • Causing diseases • Spoiling food • Occluding water lines • Destroying fabrics
Fundamentals of Microbiology • Harmful activities result when we allow them to get someplace they should not be and when we permit them to grow out of control. • First approach is to keep microbes in their proper place by preventing contamination through infection control.
Fundamentals of Microbiology • If they do get someplace where they should not be, then they must be removed, killed or kept from growing to harmful numbers through cleaning, sterilization, disinfection, growth inhibition, immunization, or anti-microbial therapy.
Fundamentals of Microbiology • The groups of microorganisms all have two things in common: • They are too small to be seen by the naked eye. • They can live on or in the human body, which may result in the development of harmful infections.
Fundamentals of Microbiology • All microorganisms can be killed by exposure to heat or chemicals unless they are on or in the body. If in the body, medications must be used. • The fastest and surest way to kill microorganisms is with heat.
Bacteria • Bacteria are a large group of one-celled microoganisms. Most bacteria are capable of living independently under favorable environmental conditions. Pathogenic bacteria usually grow best at 37 degrees Celsius in a moist dark environment.
Bacteria • Humans host a variety of harmless bacteria at all times. • They are beneficial and protect the human host by aiding in metabolism and preventing entrance of harmful bacteria.
Bacteria • An infection occurs when bacteria occurring naturally in one part of the body invade another part of the body and become harmful. • Bacterial growth is defined as an increase in cell numbers by dividing.
Bacteria • In ideal circumstances, some common bacterial cells can divide and double every 20 minutes
Bacteria • Controlling Growth • Achieved by changing the bacteria so that it can not divide into more bacteria by using chemical agents or drugs.
Bacteria • Periodontitis • Dental Caries
Viruses • Viruses are much smaller than bacteria.
Viruses • Can cause specific oral diseases • Example: Herpes labialis
Viruses • Can cause diseases elsewhere in the body that may result in lesions occurring in the mouth • Can cause bloodborne diseases, such as AIDS and hepatitis B, and other types of diseases
Viruses • Necrotizing Gingivitis from HIV • Kaposi Sarcoma from HIV
Viruses • Unlike most bacteria, viruses are not free-living. They must use both the nutrients and the metabolic machinery of living cells to multiply. • Thus, viruses are called obligate intracellular parasites.
Viruses • Because viruses use part of our own cell to multiply, it is very difficult to make drugs that just kill the virus and not hurt us. • The approach is to prevent viral diseases from occurring through immunization or infection control procedures.
Fungi Fungi include molds, and yeasts, with certain members capable of causing diseases in humans.
Fungi • In dentistry, the most important fungal infection is oral candidiasis. This is caused by the fungus Candida albicans, which may exist as a yeast cell or as a mold. • Oral infections are usually treated with topical antifungal agents
Fungi • Dermatophytosis • Oral Candidiasis
Development of Disease • An infectious disease occurs when a microorganism in the body multiplies and causes damage to the tissues. • The microorganisms that cause diseases are called pathogens.
Steps in Disease Development 1. Source of the microorganism 2. Escape from the source 3. Spread of microbes to another person 4. Entry into a new person 5. Infection 6. Damage to the body
Diseases Caused by Microorganisms • Fungi-Candidiasis Histoplasmosis Dermatophytosis • Bacteria- Dental Caries Periodontitis Tuberculosis Syphilis • Viruses- Hepatitis A, B, C HIV/ AIDS
Infectious Diseases and Pathogens • Associated with the Mouth: • Cold/ Influenza • Hepatitis A, B, C • Herpes Viruses • Measles-Rubella and German • Infectious Mononucleosis • Streptococcus Infections • Tuberculosis
Infectious Diseases and Pathogens • Most Commom Blood Borne Diseases: • HIV/AIDS • Hepatitis C • Hepatitis B
Principles of Infection Control • Standard Precautions: “Treating every patient as though they are infectious and using the same infection control procedure with all patients.”
Infectious Disease Process • This process involves three essential components: • a causative agent - what causes the disease, for example: bacteria • a susceptible host - example: human • a mode of transmission - how the bacteria gets into the human
Infectious Disease Process • All three are necessary for the spread of an infection from one person to another. When any one of them is missing the chain is broken and the possibility of infection is eliminated.
Infectious Disease Process • Causative Agent • Any microbe capable of causing disease, also called Pathogens. • Pathogens include a variety of viruses, bacteria and fungi.
Infectious Disease Process • Susceptible Host • A susceptible host is a person lacking effective resistance to a particular pathogen. • Factors that affect susceptibility include: heredity, nutritional status, use of medications, underlying disease, immunization status and age
Infectious Disease Process • The elderly and young have compromised defense systems • People can reduce or eliminate their susceptibility to many diseases, such as polio, influenza and hepatitis B, by being vaccinated against them.
Infectious Disease Process • Immunity to future infection is also acquired for some diseases, including hepatitis B, chicken pox and measles, if a person has had the disease in the past and has developed antibodies against it.
Immunizations • Immunizations strongly recommended for dental personnel • Hepatitis B • Influenza • Measles • Mumps • Rubella • Varicella-zoster
Infectious Disease Process • A mode of transmission is the mechanism by which a pathogen is transferred to a susceptible host. • For infection to occur, the pathogen must successfully travel to and pass into the susceptible host.
Infectious Disease Process • Disease Transmission in the Dental Office • Patient to dental team • Patient to patient • Dental office to community (example: to dental lab. Also includes dental team’s family)
Pathogenic Capabilities • Pathogenic capabilities depends upon four important factors: • Virulence of pathogen • Concentration of pathogen • Portal of entry into host • Host resistance
Pathogenic Capabilities • The major goal of an infection control program is to reduce the number of pathogens invading a host to a level where normal body defense mechanisms can prevent infection.
Occupational Exposure • Occupational exposure to blood and saliva may occur in several ways: • parenteral exposure (result of piercing the skin from sharp object) • contact with mucous membranes • contact with wounds and abrasions in the skin (non-intact skin).
Handwashing • For most routine dental procedures, wash your hands with soap and water. • If your hands are not visibly soiled, you may use an alcohol-based, waterless hand rub. • Hands must be dry before applying gloves.
Handwashing • Important to wash your hands: • If you inadvertently touch contaminated objects or surfaces while barehanded. • Before you put on gloves. • Immediately after your remove gloves. • Always use liquid soap.
Handwashing • Soap and Water: 1.Roll up sleeves above wrists. Remove any rings or watch during hand hygiene. 2. At the sink, turn on warm water. 3. Apply a small amount of soap and rub hands together for at least 30 seconds. 4. Rinse and dry.
Handwashing • Waterless Hand Sanitizer: 1. Roll up sleeves above wrists. Remove any rings or watch. 2. Dispensed ample amount of product into palm of one hand. 3. Rub hands together, covering all surfaces of hands and fingers. 4. Allow hands to dry.