Chain of Infection PDF

Chain of Infection Work Health & Safety HSC- Learning Outcome 3.2 1123  2 Infectious Diseases: are diseases/illnesses caused by micro-organisms, suc...

Chain of Infection Work Health & Safety HSC- Learning Outcome 3.2 1123  2 Infectious Diseases: are diseases/illnesses caused by micro-organisms, such as (1) bacteria, (2) viruses, (3) parasites or (4) fungi. Parasites Viruses Fungi (mold) Bacteria  3 1.) Bacteria: Bacteria is a single cell micro-organism having both plant and animal characteristics. Bacteria can be found in: Air Examples bacterial diseases: Tuberculosis: Air-borne Body secretions Cholera: Water-borne Clothing Meningitis Diphtheria Decayed matter Environmental surfaces Free edge of nails Skin Water Methicillin-resistant Staphylococcus aureus: is one of the more notorious antibiotic resistant bacterial strains.  4 2.) Viruses: is an infectious agent that replicates ONLY inside the living cells of an organism. VIRUSES can cause: Common colds Gastrointestinal infections Respiratory infections OTHER VIRUSES include: Chicken pox Hepatitis: Blood-borne AIDS (HIV): Blood-borne Influenza: Water droplets Measles: Air-borne  5 3.) Parasites: Parasites are organisms that grow, feed and shelter on or in another organism while contributing nothing to the survival of that organism. Examples of parasites: Fleas Head Lice Mites Ticks Worms  6 The importance of controlling infection in the workplace: Understanding the modes of transmission of infectious organisms and knowing how and when to apply the basic principles of infection prevention and control is critical for: 1. The success of an infection control program. 2. Reducing infection transmission. 3. Preventing diseases. This responsibility applies to everybody working and visiting a healthcare facility, including administrators, staff, patients and caregivers.  7 Chain of Infection: The “Chain of Infection” is a model of how infections can be prevented by breaking the chain (6-related components). The SIX (6) related components in the chain are: 1. Causative / Infectious Agent 2. Reservoir 3. Portal of Exit 4. Modes of Transmission 5. Portal of Entry 6. Susceptible Host  8 1. Causative / Infectious Agents: Causative Agent (infectious agent) is the micro-organism that is able to produce a disease or health problem. Examples: Bacteria and Viruses. Some of the causative agents are: Bacteria: causes many diseases like Tuberculosis and Cholera. Viruses: Causes many diseases like Influenza and Acquired Immunodeficiency Syndrome (AIDS).  9 2. Reservoir: Reservoir (source) is defined as a host which allows the micro- organism to live, and possibly grow, and multiply. Humans, animals and the environment can all be reservoirs for micro- organisms. - Humans/Animals: a sick person/animal who is infected, or not sick but carries the infectious agent. - Environment: soil, water, and plants are also reservoirs for some infectious agents.  10 3. Portal of Exit: Portal of Exit: a path or way or route for the micro-organism to escape from the reservoir (human or animal). The micro-organism might have one portal of exit or more. Examples: Nose Eyes Mouth Skin Blood Body fluids  11 4. Mode of Transmission: An infectious agent may be transmitted from its natural reservoir to a susceptible host in different ways. There are TWO (2) different classifications for the modes of transmission: 1. Direct Transmission: Direct contact (Person-to-Person) Droplet spread 2. Indirect Transmission: Air-borne Vehicles Vectors  12 4. Mode of Transmission (continued) : 1. Direct Transmission: A.) DIRECT CONTACT (PERSON-TO-PERSON): occurs through skin-to-skin contact, kissing, and sexual intercourse. Direct contact also refers to contact with soil or vegetation harboring infectious organisms. Examples: AIDS, Sexual transmitted diseases (Syphilis & Gonorrhea) and Lice. B.) DROPLET SPREAD: refers to spreading relatively large, short-range aerosols produced by sneezing, coughing, or even talking. Droplet spread is classified as direct because transmission is by direct spreading over a few feet, before the droplets fall to the ground. Examples: Pertussis, Meningococcal infection, Influenza and COVID.  13 4. Mode of Transmission (continued) : 2. Indirect Transmission: A.) AIR-BORNE: occurs when infectious agents are carried by dust or droplets suspended in air. Examples: Measles has occurred in children who came into a physician’s office after a child with measles had left, because the measles virus remained suspended in the air. B.) VEHICLES: may indirectly transmit an infectious agent such as food, water, biological products (blood), and fomites (inanimate objects such as handkerchiefs, bedding, or surgical scalpels). Examples: Food or water may carry Hepatitis A virus or E. coli. A vehicle may provide an environment in which the agent grows, multiplies, or produces toxin, such as Clostridium botulinum. C.) VECTORS: such as mosquitoes, fleas, and ticks may carry an infectious agent through  14 5. Portal of Entry: The portal of entry into the host is usually the same as the portal of exit from the reservoir. Examples: Nose Eyes Mouth Skin Blood  15 6. Susceptible Hosts: Susceptible Host: someone who easily and frequently gets infected with the micro- organism. Examples: Babies Children Elderly People with a weakened/low immune system Un-immunized people (Un-vaccinated people) Anyone Breaking the links in the chain of infection is the BEST way to stop 16 infection.  17 Host Responses to Infectious Diseases: Some DO NOT become infected at all Some become infected but develop NO symptoms Some become infected and develop mild/moderate symptoms Some become infected and develop severe symptoms Some die as a result of their infection The host responses to infectious diseases depends on: (1) Strength of infectious agent / its ability to produce disease (2) Level of resistance of the host  18 Control of Infection: Infection prevention and control measures aim to ensure the protection of those who might be vulnerable (susceptible) to acquiring an infection both in the general community and while receiving care due to health problems, in a range of settings. The basic principle of infection prevention and control is HYGIENE.  19 Control of Infection (continued) : The best practices to prevent infectious diseases are: 1. Written policies and procedures for infection control should prepared and available. 2. Employee screening 3. Vaccination (Immunization): powerful and cost effective! 4. Health Education 5. Follow-up and communication with the doctors regarding the employee’s health status. 6. Encouraging employees to stay home during diseases and seek medical attention. 7. Properly managing the situation upon exposure to infectious agents.  20 Reduce/slow down the spread of infections: Get the appropriate vaccines. Wash your hands frequently. Stay home if you are sick (so you do not spread the illness to other people). Use a tissue, or cough and sneeze into your arm, not your hand. Turn away from other people while cough or sneeze. Use single-use tissues. Wash your hands after coughing, sneezing or using tissues. If working with children, have them play with hard surface toys that can be easily cleaned. Do not touch your eyes, nose or mouth (viruses can transfer from your hands and into the body). Do not share cups, glasses, dishes or cutlery. Wear Personal Protective Equipment.  Thank You 800 MyHCT (800 www.hct.ac.ae 69428)