Microorganisms serve to convert complex organic compounds such as animal and plant matter into more simple forms through the process of decay.
Describe Indigenous microflora?
Microbes that live on the skin and inside the human body. Also referred to as opportunistic pathogens.
(Bacteria, fungi, viruses, and protozoa)
What is Symbiosis?
The relationship between human hosts and indigenous flora.
(Symbiont, refers to both organisms)
How many categories of symbiosis are there? and what are they?
Mutualism
Both organisms benefit from and depend on one another to a certain extend.
EXAMPLE.
-Escherichia coli, which colonizes within the human intestine, obtains nutrients from the food that humans eat.
-E coli produces vitamin K, which is essential to the blood-clotting process in humans
SYNERGIMS: subcategory of mutualism
-two organisms work together to achieve a result neither could obtain alone.
-Example: Fusobacteria and spirochetes work together to cause a disease known as trench mouth
Commensalism
One organism benefits but second organism neither benefits nor is harmed.
EXAMPLE:
Indigenous microflora on the skin of humans obtain nutrients, but do not affect the skin or human body. To a certain extend they benefit humans by occupying space and preventing other potentially harmful microbes from colonizing a process referred to as competitive exclusion.
Neutralism:Subcategory of commensalism
- two organisms occupy the same area with no effect on each other
Antagonism:Second subcategory of commensalism
-One microorganism inhibits or interferes with the growth of another.
-Example: A microbe produces waste products that are toxic to the neighboring microbes.
Parasitism
One organism benefits and the host is harmed.
EXAMPLE Endoparasites, such as intestinal worms, cause an infection and deplete the body of nutrition. Microorganism that cause an infection are called pathogens. Examples of pathogenic relationships include the following:
-commensal microbes that become opportunistic by entering through a surgical skin incision.
-Nosocomial infections (infections acquired in a hospital) such as urinary tract infections.
-Airborne viruses, such as the virus that cause the common cold.
Define Infection.
The multiplication of organisms in the tissue of a host .
Define Nonsocomial infection.
Any infection that developed while a patient is in the health care facility.
What does HAIs stand for?
Health care-associated infections
HAIs account for how many infections per year? and how many deaths? Give the percentage of infections that occur per year.
1.7 million infections
99,000 associated deaths
32% UTI's
22% SSIs
15% pneumonia
14% are bloodstream infections
(25% acquired intraoperatively, not evident till discharge)
What are the two group classifications of living cells?
-Prokaryotes
Less complex organism whose organelles are not membrane bound like those of the eukaryotes.All bacteria are prokaryotes
-Eukaryotes
Cellular structure is complex, this classification includes protozoa; fungi; green, brown and red algae; and all plant and animal cells.
What is the most common transmitted pathogen in the OR?
-Staphylococcus aureust
this is a gram-positive coccus, bacterium is common in the flora of skin, hair, and nares of the nose; 25% of people are colonized withs this microorganism.
What bacteria causes Tuberculosis? How is it transmitted?
Mycobacterium tuberculosis
Transmitted through airborne droplet nuclei, usually infects the lungs, may also infect the kidneys, bone, joints, or skin.
Viruses are nonliving particles that are completely reliant on the host cell for survival.
T or F
True
What are unique characteristics of viruses?
-Viruses are obligate intracellular parasites.
-Viral replication is directed by the viral nucleic acid within the host cell.
-Viral cells contain either DNA or RNA and a protein coat that encases the nucleic acid.
-Viral cells depend on the protein production of the host cell; the viral cell does not contain the enzymes required for the production of energy.
What is Capsid? What is it composed of?
It is a protein covering, covers the DNA or RNA of a virus helps with the attachment of the host cell. It's composed of protein molecules called capsomeres.
What is Nucleocapsid?
nucleic acid-capsid combination
How do viruses enter the body?
-Inhalation of respiratory droplets
-Exchange of body fluids by blood,semen, and mother's breast milk
-ingestion of food or water
-Bites by arthropod vectors
What are the steps of infection by the rhinovirus, the causative agent of the common cold?
1.An infected individual sneezes, thus releasing thousands of viral particles into the air.
2.A noninfected person inhales some of the viral particles and becomes infected with the rhinovirus.
3.The viral particles bind to the host cells lining the nasal sinuses and begin to rapidly replicate.
4.The host cells lyse and new viral particles are released to continue replicating in the sinuses and travel to the lungs.
5.The infected sinus cells are induced by the viral particles to real ease fluid, which enters the throat, where the viral particles invade the cells that line the throat, where the viral particles invade the cells that line the throat, causing a sore throat.
6.The body's immune response begins to fight the infection by releasing pyrogens that cause the body temperature to rise; the increased temperature helps to slow the rate of viral replication.
What are the common viral pathogens found in the OR?
-Hepatitis B (HBV)
-Hepatitis A
-Hepatitis D (Delta)
-Human immunodeficiency virus (HIV)
-Herpes simplex virus (HSV)
-Papillomavirus
-Cytomegalovirus (CMV)
-Creutsfeldt-Jakob Disease (CJD)
What does MDR stand for?
Multidrug-resistant
Describe Prion?
Short for "proteinaceous infectious particles", entirely different from other infectious agents in that they are built of proteins and do not contain DNA or RNA.
What are the two common forms of Prion diseases?
Scrapie
Disease that infects sheep and goats
Bovine spongiform encephalopathy
commonly know as mad cow
What does CJD stand for? Give description, and transmission.
Creutsfeldt-Jakob Disease
Transmission
Exact mode of transmission unknown; thought to be by percutaneous inoculation with brain tissue or cerebral spinal fluid from infected persons; transmission has been associated with use of contaminated instruments; longer sterilization times required.
Description
Rapidly progressive fatal central nervous disease characterized by dementia, myoclonus.
There are two categories of parasitic human pathogens, what are they?
Unicellular Protozoans
Multicellular Protozoans
What is the proper name for tape worms found in the human population?
Helminths
What belongs in the metazoans category and are endoparasites?
Helminth and arthropod groups
What is cysticeri? What can it cause?
Taenia solium
Pork tapeworms that can migrate out of the intestinal tract and travel to muscle and brain tissue, also the eyes.
May cause blurred vision, cause seizure, ataxia, headaches, and possibly death.
What are the groups of Protozoa?
Amebas
Flagellates
Ciliates
Coccidia
Microsporidia
Briefly describe protozoan's structure and what disease they cause?
Unicellular eukaryotes responsible for causing human disease such as malaria and chronic sleeping sickness
(African sleeping sickness)
How do the groups of protozoa move?
-Amebas
move by extending pseudopods
-Flagellates
move by using flagella
-Ciliates
propelled by the cilia that surround the cell.
-Intestinal protozoa
(coccidia & microsporidia)
transmitted by the fecal-oral route
What is the most important protozoa from the standpoint of the surgical technologist?
Entamoeba histolytica, cause of amebic dysentery. An infection often found in patients who are scheduled to undergo a sigmoidoscopy or colonoscopy.
Instruments should be extra handle due to high risk of transmission.
What is a common unicellular anaerobic protozoan, Found to the indigenous flora to the vaginal wall?
Trichomonas vaginalis. T. Vaginalis
Sexually transmitted disease. population increases when the normal acidity of the vagina is upset.
Define Mycology?
Study of Fungi
What is the cellular structure of fungi?
Eukaryotic organisms that are either unicellular yeast or multicellular molds and mushrooms.
How are the true spore formed?
Either asexual cleavage or sexual meiosis.
What is the difference between Mycoses and Mycosis?
plural: Mycosis
singular:Mycoses
Both are fungal disease, terms are varied do to the quantity of the diseases.
Cause by a common bread mold, cases increased due to increase number of organ transplants and the increase use of immunosuppressive drugs and antibiotics.
Zygomycosis
F.Y.I
Majority of fungi are opportunistic pathogens that cause disease when the host is immunocompromised.
Rapidly progressive, devastating, and destructive disease. Can cause extensive damage to the bone and tissues of the face including the loss of one or both eyes. If blood stream penetrated it can destroy cranial bones and invade brain tissue, This type of fungal disease is called?
Rhinocerebral zygomycosis.
The 3 types of precautions applied to the modes of transmission are?
Contact
(indirect-direct)
Airborne
Droplet
What Does MRSA stand for?
methicillin-resistan Staphylococcus aureus
Most hospital's policy consist of having the team member change scrubs after completion of procedure.
What Does VRE stand for?
vancomycin-resistant enterococci
Most hospital's policy consist of having the team member change scrubs after completion of procedure.
Most SSI's are acquired at the time of surgery, rather than at some point after surgery.
T or F
True
What are the two groups of microbes divided into?
Briefly give a description of each.
(Microbes found to cause SSI's)
Environmental.
sources include personal, the environment, and contaminated instrumentation
