Microbiology; Test 11/6

infectious diseases

are caused by microorganisms, account for 50% of all disease are caused by microorganisms

degenerative diseases

arthritis, caused by wear and tear and aging of the body

nutritional disorders

generally caused by deficiency, iron, B12 (etc), iron is the #1 deficiency in all age groups

metabolic disorders

diabetes and other hormone related

immune disorders

autoimmune disorders like SLE (lupus erythematosus) and RA (rheumatoid arthritis) or deficiencies of T cells, like HIV and AIDS

neoplasms

cancers

idiopathic

a disease without a known cause: hypertension

psychiatric disorders

mental health disorders

latrogenic

results from the adverse effects of treatment: like the reduction of RBCs, WBCs, and platelets

epidemiology

is the study of disease in populations

incidence rate

the number of new disease cases appearing in a particular population during a specific time period divided by the size of the population

prevalence rate

the overall frequency of a disease in a given group of the number of cases during a specific period of time

morbidity rate

the percentage of the population that becomes sick from a disease

mortality rate

the percentage of the population that dies from a given disease

epidemic

when many people in a given region have a disease at the same time

endemic

when a disease is found, to a lesser extent, but continuously in a given region

pandemic

when an epidemic spreads throughout an entire country or continent, covid was a pandemic across the world, bubonic plague wiped out 50% of the world's population, and the spanish flu killed a large number of individuals

bacteria

a single celled organism, contains both pathogens and non pathogens and opportunistic pathogens; shapes: cocci, round bacteria

types of bacteria

diplococci: 2 cocci together

streptococci: cocci in chains

staphylococci: cocci in clusters; causing strep throat, meningitis, and pneumonia

bacilli

rod shaped bacteria, causes tetanus, diphtheria, tuberculosis, E coli is a common organism

vibrio

short rods that are curved and look like a comma, cause cholera

spirilla

resembles a corkscrew, helicobacter pylori cause ulcers

spirochetes

looks like spirilla but are able to move throughout the body, one type causes syphilis

aerobes

require oxygen in order to live, most streptococcus organisms must have oxygen, most of these cause surface infections of the skin and mucous membranes or respiratory infections

anaerobes

do not require or die in the presence of oxygen, most of these organisms infect deep tissue wounds or are internal like bladder infections

rickettsia (an atypical bacteria)

these resemble, but are smaller than normal bacteria, they can only reproduce inside a host cell so they are termed obligate intracellular parasites; chlamydia is caused by this and rocky mountain spotted fever

bacteria can cause what

can cause damage to the body by directly damaging it or by making toxins; example: the bacteria clostridium botulinum causes botulism and is transmitted by a person eating spoiled, home canned food, it kills the person by paralyzing them and they must get the vaccine quickly to keep from dying of respiratory paralysis

virus

these are not really cells, they contain DNA material and can reproduce but only within a cell, they are called obligate intracellular parasites; they are so small they can only be seen with an electron microscope; because they're inside a host cell they can not be killed with antibiotics, only bacteria and other single celled creatures can be killed with antibiotics, only bacteria and other single celled creatures can be killed by antibiotics

phagocytosis

viruses cannot undergo phagocytosis so they do NOT make the WBCs increase

what do viruses cause

they cause many diseases like chicken pox, measles, mumps, influenza, covid, herpes, and polio; there are treatments available to help w/symptom relief but nothing to kill off the virus; viruses are considered self-limiting (except for rabies, which eventually leads to death); treated with antivirals like Tamiflu and Remdesivir

rabies vaccine for humans

vets, vet techs, butchers

Prions

these are infectious proteins that are even smaller than viruses, they cause encephalopathies and this damage can be seen in the brains of animals and humans injected with them, they cause Mad Cow Disease, and Creutzfeldt-Jakob disease in humans

fungi

simple, plant-like organisms that are mostly harmless, this group contains yeast and molds, considered Mycotic infections, includes: ringworm (not an actual worm) caused by the Tinea fungi and candida, which is vaginal yeast infection or thrush on the tongue; they can also cause some types of pneumonia that are very difficult to treat with antifungals

protozoas

are animal-like microorganisms, much larger than bacteria and are found in soil and H2O; includes amoebas, ciliates, flagellates, and apicomplexans (sporozoa)

amoebas

irregularly shaped blobs of protoplasm that propel themselves with a false foot, amoebic dysentery is commonly referred to as traveler's diarrhea (don't drink the water of new places)

Cilates

are covered with cilia that wave and propel it, not too dangerous to humans

flagellates

have a long whip-like tail that moves it, they cause African sleeping sickness (caused by bite of tsetse fly), giardia (causes diarrhea), trichomonas vaginalis is a common STI

apicomplexans (sporozoa)

cannot propel or move so they are obligate intracellular parasites, plasmodium vivax causes malaria

parasitic worms (helminths)

infestations

helminths

are multi-cellular organisms that can be seen with the naked eye, you do need a microscope to see their ova (eggs); includes: roundworms, hookworms, filaria, flatworms, and pinworms

roundworms

ascaris, this is the worm that infests most dogs, cats, and humans; it lives in the soil and can infect the intestines and the lungs

hookworms

these are found in the soil and can penetrate the intact skin of bare feet, they suck blood from the host and contribute to many chronic diseases

fillaria

these small thready worms are carried by insects, they infest the patient's lymph system causing filariasis, this causes swelling of the lower extremities

flatworms

tapeworms, can grow in the intestine for up to 50 feet, spread by improperly cooked meats

pinworms

common in daycares, lay their eggs around the anus, intense itching

anthropods

include spiders, mites, lice, and mosquitos who act as vectors for other organisms

pediculosis capitis

head lice, suck blood from the scalp (bed bugs are a type of lice), there are public lice and body lice

sarcoptes scabies

causes scabies, the mite can travel through close contact to the skin from other people and clothing, highly contagious, nothing scares a nurse more than scabies

identification of pathogens

this process starts w/ culture, which begins with swiping an area of the body, a urine or sputum culture of taking a blood test from the body, because they are microscopic you will not see them until they grow enough to form a colony; they need a nutrient rich bed to grow on called agar (seaweed); when the colony is big enough the microorganisms are stained for identification

gram stain

a blue-purple dye is placed on the colony and depending on the color that the organisms' stains will help the lab to narrow down the organisms; gram negative rods or gram negative cocci, or gram positive rods, or gram positive cocci

virulence

power of an organism to overcome the defenses of the body; invasive power: aggressiveness, ability to produce toxins: clostridium species, tetanus, botulism, gangrene; very difficult to treat as they are spore forming anaerobic organisms

predisposition

occupation, lifestyle, inherited traits

body defenses

formation of food infections or poisons, destruction of body cells and tissues, mechanical injury, and production of toxins

local infections

one spot

focal infections

like an abscessed tooth, infected tonsils

generalized infections

entire body

bacteremia

bacteria in blood

toxemia

toxins in blood

septicemia

generalized blood infection with organ dysfunction

pyemia

pus in blood

acute infection

rapid and severe, terminates abruptly

chronic infection

slow over period of weeks, months, or years

primary infection

first/original

secondary infection

usually caused by opportunistic organism

latent infections

dormant or hidden, like TB

mixed infections

more than one organism

incubation period

10 to 21 days

prodromal period

short period, no longer than a day or two

acute period

fever (lasts 1 or 2 days normally)

convalescent

decline in fever, start feeling better

malaise

don't feel good but can't quite put your finger on what the cause is

symptoms

changes felt by patient

signs of infection or disease

changes seen by nurse or doctor

syndrome

a characteristic grouping of signs and symptoms like polydipsia, polyphagia, polyuria, and hyperglycemia can all be indication of diabetes

therapy

course of treatment for infection

prognosis

outlook for the patient's future

prevention

stop disease before it starts, handwashing, changing linens, sterile technique

first line of defense

unbroken skin and mucous membranes

respiratory, digestive, GU tracts

cilia, acidity of urine, digestive juices, sneezing, coughing, vomiting, and diarrhea

perspiration

secretion of sweat gland, acid pH

lysozyme

anti bacteria enzyme present in skin and in our tears

cells that line many of the vascular and lymph channels

mobile phagocytes, fixed phagocytes

histamine

makes eyes water, nose run, and feel yucky

inflammatory response

most important defense mechanism

mechanical irritant

wounds

chemical irritants

poisons and acids

physical agents

frostbite and burns

living agents/antigens

microorganisms

objectives of the inflammatory response

localization of disease process, removal of cause of irritation, neutralization and destruction of toxins, repairing of damage done

characteristics of inflammatory process

heat, pain, redness, swelling, limitation of movement

inflammatory process itself

increased blood flow to are, release of histamine, leukocytes leak out, diapedesis (WBC migrate from bloodstream to source of infection), neutrophils first on scene (engulf and digest), monocytes and phagocytes follow, forming of pus and fever, and swelling

treatment of inflammation

rest inflamed part, ice, compression, elevation, and drugs