Infectious Disease 1

Question 1

PT implications for studying infectious disease

Answer 1

• infections must be treated effectively to allow full recovery and allow the patient to progress in rehab
• allow them to fully engage in PT
• side effects may impair fxn and limit performance
• prevent infection and control transmission

Question 2

Signs and Symptoms of infectious disease

Answer 2

Box 8.1?
fever, chills, malaise (earliest symptoms) sweating, nausea and vomiting, lymph node swelling

increasing number of leukocytes or a change in the types of leukocytes

Question 3

WBC response to infectious disease

Answer 3

leukocytosis (increase due to infection or inflammation)

leukopenia (decrease due to bone marrow disease, radiation, chemo or meds, inc risk of patients being infected)

Neutropenia

Question 4

Neutropenia

Answer 4

neutrophils are most abundant WBC

a reduction of them increases the risk of nosocomial infections (healthcare-associated infections, HAI)

Question 5

Normal WBC count levels

Answer 5

Normal - 5000-10000

> 10000 leukocytosis

< 4000 leukopenia

Question 6

Normal body temp (how does it differ for older adults?)

Answer 6

96.8-99.5 (avg of 98.6)
lower values for older adults

Question 7

What controls body temp?

Answer 7

Hypothalamus is temperature-regulating center

Pyrogens - protein substances and toxins cause the set point of the hypothalamic thermostat to rise

This activates the hypothalamus to conserve heat and increase heat production

Question 8

Is fever always due to infectious disease?

Answer 8

No, it may accompany inflammation, neoplastic, and immunologically mediated diseases

Question 9

Infectious causes of fever (Box 8.2)

Answer 9

UTI, Respiratory infection, catheter-relates infection, surgical wound infection, infected pressure wounds, (also colitis, peritonitis, meningitis)

Question 10

Noninfectious causes of fever (Box 8.2)

Answer 10

injured or abnormal cells incite production of pyrogens

drug reaction
pulmonary emboli
neoplasm
tissue necrosis (stroke, MI)
autoimmune diseases

Question 11

Intermittent fever

Answer 11

temperature returns to normal at least once every 24 hours

sepsis, abscesses, infective endocarditis

Question 12

Remittent fever

Answer 12

temperature fluctuates but does not return to normal

viral upper respiratory infections

Question 13

sustained or continuous fever

Answer 13

temperature remains above normal with minimal variation

Question 14

recurring or relapsing fever

Answer 14

episodic fevers lasting 1 to 3 days with 1 or more days of normal temperatures between episodes

Question 15

What occurs to some people who have serious infections?

Answer 15

Do not initially develop a fever but develop tachypneic, become confused, or develop hypOtension

most common in older adults or those with HAI

Question 16

Other signs and symptoms of infectious disease

Answer 16

abscess (pus collection that if ruptured or drained into other tissues can cause spread of infection)

rash with fever - caused by any microbe that penetrates stratum corneum, skin lesions

red streaks - develop in direction of regional lymph nodes (acute lymphangitis), bacteria may enter blood stream, often swelling of lymph nodes

inflamed lymph nodes - in acute infection, nodes are tender, asymmmetric and enlarged, and overlaying skin may be red and warm

joint effusion - accumulation of excess fluid in a joint, associated with infectious arthritis

Question 17

Why are older adults more susceptible to infectious diseases

Answer 17

• increases susceptibility due to immunoescnece and comorbidities
• increased morbidity and mortality, especially in frail and debilitated older adult
• decrease in number of naive T cells and increase in memory T cells
• slower to response and require a stronger stimulus

Question 18

What specific part of the immune system is impacted most by aging?

Answer 18

As thymus ages, decrease number of naive T cells released, = decreased diversity and proliferation rate = difficulty responding to antigens especially viruses and ability to stimulate B cells to make antibodies

Question 19

What factors outside the immune system can cause increased susceptibility for older adults?

Answer 19

• atrophic skin more easily damaged
• decreased cough and gag reflex make it harder to control secretions
• decreased bronchiolar elasticity and mucociliary activity (doesn’t clear mucus that’s catching pathogens)
• denture associated infections
• more likely to have implanted device

Question 20

Why do we have to be extra careful when working with older adults?

Answer 20

Symptoms of infection is often VAGUE, BLUNTED OR ATYPICAL

More serious infections may occur yet with little or no fever because of an impaired thermoregulatory system or masking effects of drugs

^ Lower threshold of temperature for infection should be used (99 or 100)

Question 21

Incubation period

Answer 21

the period between the pathogen entering the host and the appearance of clinical symptoms

disease symptoms herald the end of the incubation period

Question 22

Subclinical infection

Answer 22

no apparent symptoms are evident other than an identifiable immune response of the host (ex; increase in antibodies)

Question 23

Infectious disease

Answer 23

clinically apparent infection in which the host-parasite interaction causes obvious injury and is accompanied by one or more clinical symptoms

Question 24

latent infection

Answer 24

occurs after a microorganism has replicated but remains dormant or inactive in the host, sometimes for years

Question 25

period of communicability

Answer 25

time period when an organism can be shed (when disease can be contagious) may be towards the end of the incubation period meaning the person can be asymptomatic and still transmit the disease!

Question 26

What is larger, bacteria or virus?

Answer 26

bacteria

Question 27

What is the chain if transmission

Answer 27

KNOW TABLE 8.2 (slide 40) transmission of a pathogen depends on: pathogenic agent a reservoir portal of exit from the reservoir mode of transmission portal of entry into host susceptible host

Question 28

How are pathogens different than parasites?

Answer 28

Pathogens create a disease response that hurts their host and eventually kill the pathogen

Question 29

What determines the likelihood of a pathogen producing disease and the type it produced?

Answer 29

the characteristics of the organism and the susceptibility of the host

Question 30

Pathogenicity

Answer 30

the ability of the organism to induce disease, depends on the organisms speed of reproduction in the host, the extent of damage to tissues, and strength of any toxin released by the pathogen

Question 31

Virulence

Answer 31

the potency in the pathogen in producing severe disease and is measured by the case fatality rate (the number of people who die of the disease divided by the number of people who have the disease

Question 32

opportunistic pathogens

Answer 32

don't cause disease in those with intact immune systems but cause devastating disease in people with severe defects in host defense mechanisms

Question 33

Carriers of disease (reservior)

Answer 33

carrier maintains an environment that promotes growth, multiplication, and shedding of the parasite without exhibiting signs of disease (hepatits) human and animal reservoirs can be asymptomatic or symptomatic carriers

Question 34

Examples of portal of exit

Answer 34

secretions and fluids excretions (urine and feces) open lesions exudates (pus from open would or ulcer) HIV has multiple portals of exit

Question 35

Transmission - direct contact vs indirect contact

Answer 35

indirect - inanimate and intermediate objects (fomite), any items that come into direct contact with the infected person

Question 36

Airborne vs Droplet transmission

Answer 36

Airborne - less than 5 um, can be suspended in the air for several hours Droplet - larger than 5 um, do not remain suspended in air but fall out within 3 feet of the source travel only a short distance

Question 37

Airborne vs Droplet transmission DISEASE EXAMPLES

Answer 37

Airborne - tuberculosis, chicken pox, rubeola measles Droplet - influenza

Question 38

Vehicle transmission

Answer 38

Occurs when infectious organisms are transmitted through a common source (contaminated food, water, and IV fluid) to many potential susceptible hosts

Question 39

Vector-borne transmission

Answer 39

insects and/or small animals that act as intermediaries between two or more hosts

Question 40

Portal of entry

Answer 40

may enter new host by ingestion (GI), inhalation (respiratory) or bites or injury if the skin microbes commonly enter through contact with mucus membranes and less frequently, transplacentally

Question 41

Host susceptibility - what makes someone more susceptible

Answer 41

biologic and personal characteristics - age, sex, ethnicity and heredity general health - nutrition, hormone, diseases, drug use, sexual practices inadequate or absent hand hygiene underlying medical disorders immunosuppressive agents and corticosteroids breaches of body integrity (nasal tubes, catheters, respiratory tubes, IV devices, chest tubes)

Question 42

Lines of defense

Answer 42

first-line - microbial antagonism of the normal flora of microorganisms second - inflammation process third (immune response)

Question 43

Control of transmission

Answer 43

goal is the break the chain of transmission at most cost effective points education isolation and barriers comprehensive immunization prophylactic antibiotic therapy improved nutrition, living conditions and sanitation avoid risk taking behavior - proper handling of disposal of secretions, excretions and exudates, isolation of infected clients

Question 44

CDC standard precautions for all patient care

Answer 44

assume any person may be contagious all clients receiving therapy (and this in contact with health care workers) may be asymptomatic hosts during the period of communicability

Question 45

Infectious waste

Answer 45

blood and components disposable sharps (used or unused) urine, stool or emesis if contaminated with blood vaginal secretions semen CSF synovial fluid pericardial fluid amniotic fluid

Question 46

safe waste

Answer 46

cotton balls, band-aids gloves, masks, PPE nasal secretions sputum feces urine vomitus tears sweat

Question 47

What is HAI?

Answer 47

Health care-associated infection (previously nosocomial infections) infections that develop in hospitalized person that were not present before admission results in prolonged stay, more $ and increased morbidity and mortality most caused by pneumonia, GI tract infection (C. diffiucle) and surgical site infection (SSIs)

Question 48

Causes of HAI

Answer 48

frequent use on invasive devices increase use of immunosuppressants and antibiotics more colonization and infection by multidrug-resistant organisms greater debilitation and severity of illness of hospitalized clients who acquire these infections lack of hand hygiene predisposes people CENTRAL LINE-associated bloodstream infections (CLABSIs) Catheter-associated urinary tract infections (CAUTIs) Ventilatory-associated pneumonia (VAP) Surgical site infection (SSIs)

Question 49

What is the best way to prevent HAI?

Answer 49

Hand hygiene, must be done routinely even when gloves are used

Question 50

When should you wash your hands (vs using sanitizer)?

Answer 50

when hands are visibly spoiled with blood or body fluid before eating after bathroom, proven or suspected exposure to Bacillus anthracis or Clostridioles diffcle

Question 51

Box 8.6

Answer 51

Probably don't need but read over

Question 52

Most infectious diseases are confined to where?

Answer 52

specific organ systems