Pathogens are organisms that cause disease and include viruses, bacteria, and fungi. They spread through contact with bodily fluids, ingesting contaminated food or water, or personal contact. Pathogens can be controlled through sterilization, disinfection, antisepsis, or antibiotics. Inflammation is the body's response to injury and is characterized by pain, swelling, redness, heat, and impaired function. It involves the stages of tissue injury, chemical release, leukocyte migration, and tissue healing. Immunity protects the body from infectious disease and involves the innate immune system of physical barriers and physiological factors as well as the adaptive immune system of antibodies and T cells that strengthens upon exposure to pathogens.
2. Pathogens Definition A pathogen is any organism that causes a disease in another organism.
3. Types of Pathogens Viruses- which cause chicken pox Bacteria- which cause food poisoning Fungi - which cause ringworm, athlete’s foot, and Oral thrush.
4. How Pathogens are spread Contact with bodily fluids Ingesting undercooked food Swimming in contaminated water Personal contact thru Saliva, feces, intercourse and unsanitary practices
5. Control of Pathogens Pathogens can be controlled by Sterilization- Complete removal of all pathogens Disinfection- Inhibition of pathogens by disinfectant Antisepsis -Inhibition of pathogens on living surface by antiseptic Antibiotic-An agent that is used to kill pathogens inside the host Body, (naturally produced by some microbes)
6. Inflammation What is inflammation? Inflammation is the body's basic response to injury.
7. Signs of inflammation Inflammatory reactions are characterized by 5 distinct sign Pain- due to chemical released by damaged cells Edema- due to influx of fluid into damaged region Redness- due to expansion of the blood vessels Heat- due to increase in blood flow Imperative function- due to increased swelling and pain
8. Stages of inflammatory reaction Tissue injury- Damage that occurs during trauma Release of Chemicals – Histamine Prostrogladins , Kinins Leukocyte migration- Macrophages and Neutrophils- They neutralize and engulf harmful bacteria and ingest them
9. Tissue healing Collagenation- Wound healing, Occurs toward inflammatory process Revascularization- Damaged area forms new capillaries for blood in the region Proliferation- Which lasts up to 4 weeks Remodeling - New cell mould to produce a functioning tissue
10. Immunity What is immunity? Immunity - protection from disease and especially infectious disease. Cells and molecules involved in such protection constitute the immune system The response to introduction of a foreign agent is known as the immune response.
11. Types of immunity Innate or natural immunity- Made up of several components Physical barriers are the first line of defense against infection.E.g.The skin and mucous membranes Physiological factors-such as pH, temperature and oxygen tension limit microbial growth Protein secretionssuch as lysozyme also help resist microbial invasion. Molecules such a C-reactive protein are of considerable importance in protection against infection.
12. Types of Immunity Adaptive or acquired Immunity- Develops to meet the specific needs brought about by an individual’s circumstances. Constantly evolves its capacity to defend the body against pathogens. Strengthened as a result of exposure to diseases Vaccinations also facilitate the adaptive system’s efficiency Leukocytes, commonly known as WBC are the dedicated agents of acquired immunity
13. Types of Immunity Adaptive immune system can be broken down into two components: Humoral immunity- involves the production of immunoglobins (antibodies) by B cells in response to bacteria and viruses. Cell-mediated immunity- involves the production of immunoglobins by T cells in response to virus-infected cells.
