Unit 8 Infection control in clinical setting.pptx

Nursing foundation-Infection control in clinical setting for 1st year BSc Nursing students

1. INFECTION CONTROL IN CLINICAL SETTINGS

2. Definition : According to WHO, an infection is  the invasion  and  multiplication  of  harmful microorganisms , such as bacteria, viruses, or parasites, within a host organism. These infections can cause diseases by disrupting the normal bodily functions. An  infectious disease , also known as a  transmissible disease  or  communicable disease , is an illness resulting from an infection.

3. Nature of Infection: Pathogens: Microorganisms that are capable of causing diseases. Infection: results when a pathogen invades & begins growing within the host. Colonization: Presence & growth of micro organisms within the host but without tissue invasion & damage. Disease: results only if & when tissue functions are impaired. Eg Skin lesions, burns.

4. CHAIN OF INFECTION

5. Chain of Infection: Refers to a series of events or steps that enable infections to spread between organisms. Includes 6 components & explains how pathogens can spread from reservoirs to susceptible hosts. An infection will develop if this chain remains intact. Nurses & health care workers use infection prevention and control practices to break the chain so that infection will not develop.

6. 1. Infectious Agents: Microorganisms include bacteria, viruses, fungi and protozoa. The potential for microorganism or parasites to cause disease depends on the following factors: Sufficient number of organism Virulence or ability to produce disease Ability to enter and survive to the host Susceptibility of host. 2. Reservoir: It is where a pathogen can survive. Skin of pts, carriers, animals, food, water insects, and inanimate objects & the envt etc.

7. 3 . Portal of exit: The path by which a pathogen leaves its host. usually corresponds to the site where the pathogen is localized.  4. Mode of transmission: Method of transmission by which the organism moves or is carried from one place to another. Direct contact or indirect contact with infected source, contaminated air, water, blood, food, flies, mosquito etc. Major mode of transmission of microorganisms occurs in the hands of the health care providers.

8. 5 . Portal of entry: Opening where the pathogen enter the susceptible host. Body openings (e.g., mouth, eyes, urinary tract, respiratory tract), incisions, wounds, catheters. 6. Susceptible Host: Whether a person acquires an infection depends on susceptibility to an infectious agent. The person at-risk: patient or healthcare workers Factors affecting susceptibility (e.g., age, health, co-morbidities, immune system, nutrition, infective dose, medications)

9. TYPES OF INFECTION Primary :- Initial infection with a micro organism Secondary :- primary infection lowers the resistance of the host and later gets infection with another microorganisms. Re-infection :- subsequent infection with the same organism Cross :- pt suffering from a disease new infection is set up from another source Noso- comial / HAI :- cross infection occurring in hospitals Iatrogenic :- infection is acquired during therapeutic or investigative procedures Focal :- infection at localized site like appendix and tonsils, general effects are produced Systemic :- infection thoughout the body or system. Subclinical :- clinical symptoms of an infection are not apparent

10. Clinical :- An infection with obvious observable & detectable symptoms. Local :- invading microorganism are limited to a relatively small area of the body Systematic :- microorganisms or their products are spread throughout the body by blood or lymph Mixed :- two or more microbes infecting same tissues Acute :- have a short duration Chronic :- Have a long duration Latent :- parasite after infection, remains in a latent or hidden form & produces clinical diseases when the host resistance is lowered. Pyrogenic :- pus formation Fulminating :- Occur suddenly and with severe intensity.

11. STAGES OF INFECTIONS Incubation period:- Interval between entrance of pathogen into body and appearance of first symptoms. ex:- common cold 1-2 days. Prodromal stage:- Interval from onset of non-specific signs and symptoms to more specific symptoms. During this time, microorganisms grow and multiply and patient is more capable of spreading disease to other. Illness stage:- interval when patient manifests sign & symptoms specific to particular disease. Ex. : common cold: sore throat, rhinitis, high fever, parotid and salivary gland swelling. Convalescence:- interval when acute symptoms of infection disappear unit the individual regain his normal health. Length of recovery depends on severity of infection and patient’s general health status. N.B: Infectious disease contagious during all these stages.

12. MODE OF DIEASE TRANSMISSION Direct contact: (skin to skin, mucosa to mucosa or mucosal to skin of the same or another person, Eg Ringworm, Scabies, head lice) Droplets: (respiratory secretions, Eg Flu, Whooping cough, COVID 19) Air borne: Contact with soil ( Eg Hookworm, Inoculation into skin or mucosa: ( Eg Dog Bite) Transplacental (vertical): Eg HbAg , HIV

13. FACTORS INFLUENCING SUSCEPTIBILITY TO INFECTION Age Heredity Stressors Occupation Living Condition Co morbid Disease Condition Immune Suppression Treatment/ Medications Impaired Nutritional Status

14. RISK FACTORS FOR INFECTION : INADECQUATE PRIMARY DEFENCE Broken skin or mucous membrane. Traumatized tissue. Decreased ciliary action. Obstructed urine outflow INADECQUATE SECONDARY DEFENCE: Reduced hemoglobin level. Suppression of white blood corpuscles (drug or disease-related). Suppressed inflammatory response (drug or disease-related). Low WBC count ( leukopenia ).

15. RISK FACTORS IN OLDER ADULTS Thinner dermal and epidermal layers of skin, decreased sweat and skin elasticity. Reduced sensitivity. Circulatory and heart disorders like congestive heart disease, calcified valves of heart. Reduce elasticity of veins, blood pooling in lower extremities. Decreased cough reflex Exposure to nosocomial infections

16. BODY DEFENCE AGAINST INFECTIONS Whenever the infectious agent enters in the body tissues, persons have defense mechanism, which protects the person from infections. There are 3 lines of defense against infections: 1 st Line of Defense Non Specific Defense/ Innate Immunity 2 nd Line of Defense 3 rd Line of defense Specific Defense / Adaptive Immunity

17. 1 st Line of Defense Anatomical & physiological barriers which prevents the entry of micro organisms. Intact skin and mucous membranes act as the first barrier against microorganisms Alveolar macrophages of the Lungs , high acidity of the stomach, urinary system, low vaginal pH all helps in preventing infections.

18. 2 nd Line of Defense These includes: Phagocytic Leukocytes: migrate to infection sites & engulf foreign bodies. Inflammatory responses:- occur in response to the injurious or infectious agent. It is a defensive mechanism that eliminate or dilute the injurious agent. Anti Microbial Proteins: regulate immune activity within the body They also prevent the future spread of the injury and encourage the repair of the damaged tissues. Fever: increases body tempr to activate heat shock proteins & suppress microbial growth & propagation.

19. 3 rd Line of Defence These are the specific lymphocytes that produce antibodies as part of the adaptive immune response. It is broadly classified Antibody responses & cell mediated immune responses

20. Antibody mediated Response: Also known as Humoral immunity. 2 types of immunity-active & passive one. In active immunity the person produces antibodies in response to a natural antigen like microorganisms & artificial antigen like vaccines. In passive immunity the person develops a natural or artificial antibody. Here the β cells are activate d to circulate in the blood stream where they bind to the antigen, inactivating the micro organism & the toxins.

21. Cell-mediated Response Also known as Cellular immunity , which comes through T cells. Here the activated T cells can detect the microbes hiding inside the host cells & can either kill the infected cells or help the other cells remove the microbe. This immune response that does not rely on the production of antibodies.