Unit 1

If a pathogen is present it doesn't mean that infection will occur. Microogranism is present or invades a host but does not cause infection it is a colonization. Infections are infectious or communicable

the entry and multiplication of an organism, you need a host, invasion of a susceptible host by an organism. Only goes to diseased state if organisms can multiply

When pathogens multiply and cuase signs or symptoms it is symptomatic. if signs and symptoms are nto present it is asymptomatic

can be transmitted directly from one person to another

• Infections agent/pathogen
• reservior
• portol of exit
• mode of transmission
• portal of entry
• host

• include bacteria, viruses, fungi and protozoa
• resident flora = normal flora on skin they survive and multiply w/o causing illness. major part of body's protection
• transient flora = attach to skin when person has contact with another person. Can be transmitted from bedpan or contaminated dressing (must be washed off to prevent being spread)

• Must have sufficient # of organisms (dose)
• must have virulence or ability to survive in the host or outside the body
• must have ability to enter and survive in the host
• host must be susceptible
• (a reservior is a place where pathogens can survive but may or may not multiply)

Humans, animals, insects, food, water

food, oxygen, water, temp, pH and light

• skin and mucous membranes
• respiratory tract
• urinary tract
• GI tract
• Reproductive tract
• blood

• Direct contact (person to person)
• indirect (personal contact with inanimate object, dressings, needles)
• droplet (coughing sneezing, pneumonia, streplarger than 5mcg)
• Airborne (coughing, sneezing, measles, variceela smaller than 5mcg)
• vehicles (contaminated items, water, drugs, blood)
• vector (flies, mosquito)

degree of resistance to a pathogen. Factors that influence susceptibility include age, nutritional status, presence of chronic disease, trauma, smoking. Person does not become ill until they become susceptible to the number (dose) of microorganisms that are capable of producing the infection

cilia, resident flora, skin

• Incubation period - interval b/t entracnce of pathogen and appearance of 1st symptom
• prodromal period - interval from onset of nonspecific signs and symptoms to more specific symptoms. MO grow and multiply
• illness - when client manifests signs and symptoms to specific type of infection
• convalescence - interval when acute symptoms disappear

client experiences localized symptoms such as pain, tenderness, redness at wound site

affects entire body insterad of just a single organ or part, can be fatal if left untreated

MO that naturally reside on the skin, saliva, and oral mucosa, and GI and GU tract. Participate in maintaining health. Normal flora secrete antibacterial substances in GI tract. Skins normal flora exert a protective bactericidal action that kill organisms on the skin. Normal flora in mouth impair growth of invading microbes. Maintain a sensitive balance with other MO to prevent infection (c. diff happens when antibiotics wipe out or sterilize bacteria in gut)

body organs have unique defenses against MO. Each organ system has a defense mechanism physiologically suited to its specific structure and function. Ex = moist mucous membranes and cilia to move out cellular debris. skin is # 1 defense

Body's cellular response to inury, infection, or irritation, a protective vascular reaction that delivers fluid, blood products, and nutrients to an area of inury. The process neutralizes and eliminates pathogens. Inflammatory response can be triggered by physical agents, chemical agents, MO

increase in WBC, fever caused by phagocytic release of pyrogens from bacterial cells that cause rise in hypothalamic set point, and vomiting

accumulation of fluid and dead tissue and RBCs form and exudate at the site of inflammation. Can be serous (clear, plasma like), sanguineous (containing RBCs) or purulent (containing WBCs and bacteria)

The damaged cells are replaced with healthy new cells. New cells undergo maturation until the same structural characteristic sand appearance as previous cells. If edema is chronic tissue may fill with granulation tissue which not as strong as tissue collagen but assumes the form of scar tissue

health care acquired infections

• look at defense mechanisms
• susceptibility
• knowledge of how infections are transmitted
• review of disease and travel history
• immunization and vaccination history

• Age - infant and older adult more prone
• nutritional status - inadequate diet reduces body's defenses against infections and impairs wound healing
• stress - ATCH acts to increase serum glucose levels and decreased anti inflammatory responses thru release of cortisone (ex = meningitis with college students)
• disease process (morbidity) - clients with immune system diseases are at increased risk for infection
• Medical Therapy - drugs and medical therapies compromise immunity to infection. Anti inflammatory drugs cause protein breakdown and impair inflammatory response against bacteria and other pathogens

• risk for infection
• imbalanced nutrition: less than body requirements
• impaired oral mucous membranes
• risk for impaired skin integrity
• social isolation
• impaired tissue integrity
• validate data
• accuracy of diagnosis

through nutritional support, maintenance of physiological protective mechanisms, recommended immunizations

• Airborne - droplet smaller than 5 mcg (measles varicella)
• droplet - larger than 5 mcg (pneumonia, strep)
• contact - direct client contact (MRSA)
• protective - allogenenic hematopoietic stem cell transplants (protecting the client, private room with 12 or more air exchanges per hr)

• Negative-pressure airflow prevents infections from flowing out of the room
• positive-pressure used for highly susceptible immunocompromised clients
• anteroom-adjoining room that contains hand hygiene and PPE

• mask
• gloves are removed first
• gloves, eyewear, gown, mask

• insertion of IVs
• suctioning the trach
• inserting catheters
• reapplying sterile dressings