NURS3800 Module 8: Infection

What are the 2 main types of treatment in infections?

1. antimicrobials

- antibacterials

- antivirals

- antifungals

2. surgical intervention

- incision and drainage for abscess

- debridement

- removal of infected tissue/organs

The respiratory tract is an example of which type of portal of entry?

a. penetration

b. ingestion

c. inhalation

d. direct contact

c. inhalation

What is normal flora?

microbes that live on and in body without causing apparent harm

Compare colonization vs infection.

- colonization: microbe is present in the host

- infection: microbe is replicating and causing harm in the host

What does severity of illness depend on?

- virulence of the microorganism

- health of the host

What is an opportunistic pathogen?

- one that invades the tissues when the body defenses are suppressed

- normal flora can be an opportunistic pathogen

When both the microbe and the host benefit, the relationship is called _________.

mutualism

When the microbe benefits and the host is unaffected, the relationship is called ________.

commensalism

When the microbe benefits and the host is harmed, the relationship is called ________.

parasitism

What are the different agents of infectious disease?

- prions

- viruses

- bacteria

- fungi

- parasites

- rickettsiae

- chlamydiae

What are key characteristics of prions?

- proteins that are not folded properly

- no DNA or RNA

- unable to replicate

- cause neurodegenerative disease

- transmission by injection, transplant, food

- resistant to heat, disinfectants, radiation

- antibiotics are not effective

What occurs in bovine spongiform encephalopathy (BSE)/ Mad Cow disease?

prions infect cows and poke holes in their brain and spinal cord which causes the cows to die

What occurs in Creutzfeldt-Jakob disease?

humans eat cows infected with prions that cause Mad Cow disease

What are key characteristics of viruses?

- most frequent cause of human illness

- smallest pathogen

- no cellular structure

- hijacks the host's cells

What is a virus with DNA called?

adenovirus

What is a virus with RNA called?

retrovirus

What are the 3 parts of a virus?

- virion: the infectious particle

- genetic material: either DNA or RNA

- capsid: protein coat surrounding genetic material

Rhinovirus, influenza, EBV, CMV, SARS CoV-2 are examples of _______.

viruses

What are key characteristics of bacteria?

- single-celled

- prokaryotes

- can live independently

- classified by microscopic appearance

- use the host for food and shelter

What are the 3 bacterial shapes?

- cocci: circular

- bacilli: rod

- spirilli: spiral

What are the 2 bacteria growth patterns?

clusters and chains

Compare Gram + and Gram - bacteria.

+:

- stains purple

- thick cell wall

- majority of bacteria

-:

- stains pink

- thin cell wall with an additional outer membrane

- harder to treat

Strep throat is caused by _________.

group A streptococcus pyogenes

All newborns are checked for ________ because it can lead to meningitis.

group B streptococcus

What are some common antibiotic resistant bacteria strains?

- MRSA

- VRSA

- VRE

- C. diff

What conditions occur when the blood gets infected?

- multi system organ failure

- sepsis

- septic shock

Compare endotoxins and exotoxins.

endotoxins:

- not proteins

- located in the cell wall

- released when bacteria burst

- mostly Gram -

exotoxins:

- proteins

- produced inside the bacteria

- exit during growth

- mostly Gram +

What are key characteristics of fungi?

- eukaryotes

- reproduce by spores

- include yeasts and molds

- live in soil

- normal flora of the mouth and GI tract

What is mycosis?

fungal infection

What are the 3 types of parasites?

1. protozoa: ex. plasmodium parasite transmitted by mosquitos

2. helminths: worms

3. ectoparasites: fleas, ticks, lice, mites

Which type of white blood cell kills parasites?

eosinophil

What is rickettsiae?

a bacteria that can only be transmitted by vectors

What causes Rocky Mountain Spotted Fever and typhus?

rickettsiae

What is chlamydiae?

- a bacteria

- transmitted directly

- common cause of STIs

Which agent of infectious disease causes candid albicans?

fungus

Which agent of infectious disease causes malaria?

parasite

What are examples of sources of infection?

- endogenous: opportunistic normal flora

- exogenous: from the environment such as water, food, air, vector

- direct contact with another person

- fomite: inanimate object

What is the function of a biofilm?

to protect bacteria from antibiotics

What are the modes of human pathogen transmission?

- airborne

- contaminated water

- direct contact

- bloodstream

- vector

Broken skin is an example of which type of portal of entry?

a. penetration

b. ingestion

c. inhalation

d. direct contact

a. penetration

The GI tract is an example of which type of portal of entry?

a. penetration

b. ingestion

c. inhalation

d. direct contact

b. ingestion

The urogenital tract, pregnancy, and birth are examples of which type of portal of entry?

a. penetration

b. ingestion

c. inhalation

d. direct contact

d. direct contact

What are clinical symptoms associated with systemic infection?

- fever

- myalgia: muscle pain

- headache

- lethargy

- tachycardia

- tachypnea

- leukocytosis

What are the stages of infectious disease?

1. incubation:

- from exposure until symptoms appear

- time varies based on disease

2. prodromal:

- initial nonspecific symptoms appear

3. acute:

- maximum impact of symptoms

4. convalescent:

- symptoms begin to resolve

5. resolution:

- total elimination of the pathogen

- no signs and symptoms

What is a biofilm?

collection of microbes living on a surface in a complex community

What is a localized infection?

one that is confined to one site

What is a disseminated infection?

infection spreads beyond the primary site of infection through the blood

What is an abscess?

localized pocket of infection composed of devitalized microbes and host WBCs

How are abscesses treated?

incision and drainage, followed by the removal of necrotic tissue

What is culture and sensitivity?

- culture: process of growing the bacteria outside of the body to identify it

- sensitivity: test to see which antibiotic is the most effective

Which agents of infection can be identified with cultures?

- bacteria

- fungi

- mycoplasmas

What 2 diagnostic tests can be used for active viruses?

- antigen: detects specific proteins on the surface of the virus

- NAAT/PCR: detects genetic material

What diagnostic test can be used to detect a virus several weeks after exposure?

antibody: serology or antibody titer

Would antibiotics be used in a viral infection?

no

What are consequences of antibiotic overuse?

- secondary infections

- side effects

- multi-drug resistance

- interruption with microbiome

Staphylococcus aureus commonly found in the skin, nares, and other body sites of patients without any signs and symptoms of infection is known as which of the following conditions listed below?

a. An opportunistic infection

b. A parasitic infestation

c. Bacterial colonization

d. A saprophytic infection

c. Bacterial colonization

The nurse will most likely assess which of the following clinical manifestations in a client who was diagnosed with Creutzfeldt-Jakob disease?

a. Change in behavior and memory and loss of coordination leading to encephalopathy

b. Gastrointestinal problems like vomiting and diarrhea

c. Muscle inflammation and edema, making movements very painful

d. Projectile vomiting, hypertension, and drowsiness caused by elevated ICP

a. Change in behavior and memory and loss of coordination leading to encephalopathy

Which of the following procedures reduces the potential for infection primarily by addressing the portal of entry?

a. Wiping down common areas with buffered bleach on a regular basis

b. Wearing gloves when contact with blood or body fluids is anticipated

c. Disposing of soiled clothing and bed linens in a dedicated receptacle

d. Isolating patients who have antibiotic-resistant infections

b. Wearing gloves when contact with blood or body fluids is anticipated

Which of the following scenarios best describes an example of infection originating with a fomite?

a. A client who contracted hepatitis C through sharing a contaminated syringe with an infected person

b. A nurse with a positive tuberculin screening test (PPD) after admitting a patient diagnosed with tuberculosis (TB)

c. A woman who contracted Lyme disease after a tick bite

d. A man who has been diagnosed with trichinosis after eating undercooked pork

a. A client who contracted hepatitis C through sharing a contaminated syringe with an infected person