hello quizlet
Home
Subjects
Expert solutions
Create
Study sets, textbooks, questions
Log in
Sign up
Upgrade to remove ads
Only $35.99/year
Medical Microbiology Final Exam, Unit 5 Study Guide
Flashcards
Learn
Test
Match
Flashcards
Learn
Test
Match
Terms in this set (154)
Oral normal flora
>400 different species of bacteria
> 12 billion total
Contributed by kissing, eating, finger licking, etc.
Promote tooth decay and bad breath
Esophagus/stomach normal flora
None permanent
Stomach acid environment prevents normal flora
+/- Helicobacter pylori
Small intestine normal flora
First part of the duodenum and jejunum
Transient Lactobacillus and Strep
Ileum normal flora
Many Gram negative, facultative anaerobic members of family Enterobacteriaceae (Escherichia coli)
Obligate anaerobes (Bacteroides and Clostridium)
Large intestine normal flora
Feces are composed of > 50% Bacteroides spp. by weight and volume
Theses bacteria ferment indigestible stuff (Cellulose)
Produce gas (Flatulence)
Production of vitamin K (and a few other vitamins)
Important in production of clotting factors for blood clotting
Food poisining
where the bacterial TOXINS are ingested - bacteria need not be ingested, or if ingested, need not colonize
The bacteria actually multiply in the food and produce toxins, which are ingested
difference between Secretory/watery and Inflammation diarrhea
Secretory is due to a toxin/virus that changes the fluid balance in intestines. Inflammation is due to invasion of the intestinal wall.
Secretory/water Diarrhea
Bacterial toxin or virus alters the fluid balance in the intestines. Often due to toxicities.
Inflammation
Invasion of the intestinal wall with inflammation and a release of leukocytes (+/- erythrocytes) into the intestinal lumen
bacterial food poisioning
Caused by ingestion of food contaminated with preformed toxins
Tissue damage is due to the TOXIN, not the bacteria
Toxin-producing organisms may be ingested along with the toxins and can continue to produce toxin
Usually secretory diarrhea
Tissue damage in bacterial food poising is due to?
The toxin NOT the bacteria.
Microbial food poisonings are
intoxications rather than infection
Enterotoxin
Exotoxins affecting the intestines - Inflame the intestinal lining and inhibit water absorption
Staphylococcus aureus stain/shape
Gram positive cocci in clusters
Staphylococcus aureus
Toxin is absorbed into the bloodstream and acts on the mucosa of the intestine
S/S:Abdominal pain, secretory diarrhea, vomiting, nausea, afebrile
Ingestion; Food poisoning; mayonnaise containing and/or dairy products ....Vomiting, little or no diarrhea, no fever
Clostridial perfringens
Enterotoxin released under anaerobic conditions
When under-cooked meats/gravies are kept warm
***The organism and the toxin can BOTH infect tissues
Gas gangrene occurs when spores infect deep wounds
AKA Anaerobic cellulitis
Enteritis
Inflammation of the intestine
Most often the small intestine, and causes diarrhea
Dysentery
Large intestinal inflammation -Severe diarrhea , often containing mucous or blood or even pus (Inflammatory)
Enteric Fever
a systemic disease that begins in the GI tract, but may not have any GI symptoms. In enteric fevers, the organisms invade through the intestine and become systemic (Bacteremia
In which enteric disease is leukopenia common?
Typhoid fever
Thypoid fever
Salmonella typhi
Lymphatic tissues invaded and phagocytes disseminate organisms throughout the body
Multiply intracellularly and released from bile to re-infect Peyer's patches and other lymphoid tissue
Signs and Symptoms of Thypoid fever
Rose spots on trunk and abdomen
Abdominal distention and tenderness
Splenic enlargement
Leukopenia is significant (unlike most bacterial infections where leukocytosis is common)
Legionnarie's Disease
is not contagious from physical contact, you have to inhale the microbe to get this disease
Normal flora of the respiratory tract
Staphylococcus aureus and S. epidermidis
Pathogenic Mecanishm
Growth in host cells (intracellular) = viruses, Chlamydia spp.
Legionnaire's disease
Legionella pneumophila (Gram negative rod).
Legionella pneumophila
Weakly Gram negative aerobic bacillus
Tuberculosis (TB)
Mycobacterium tuberculosis
Acquired by inhalation of droplet nuclei or respiratory secretions
Mycobacterium tuberculosis
Straight or slightly curved rods, acid fast staining, obligate aerobes
TB
Large amount of fluid released, causing pneumonia-like symptoms
Lesions become chronic granulomas (tubercles) or produce massive tissue necrosis with caseous (cheesy) appearance
Miliary tuberculosis
Spread of microbes to other body tissues via the circulatory system, due failed host immunological response
Lesions can rupture causing bloody sputum
Granulomas can develop and keep organisms walled off for decades until immune impairment occurs
Disseminated tubercles - Extra-pulmonary tuberculosis
SARS (Severe Acute Respiratory Syndrome)
Causative agent - Coronavirus
Spread via contact with infected persons in aerosols, fomites, etc
Histoplasmosis
Chicken houses and bat caves
Cryptococcus
budding yeast (Birds are mechanical vectors)
Coccidioidomycosis (Valley fever)
influenza-like disease
Aspergillosis
"farmer's lung"
Clostridium difficile
Gram positive, spore-forming, anaerobic rod
Iatrogenic (nosocomial) infections
Super-infection - Often
cholera
Vibrio cholerae - Comma-
shaped, salt-tolerant (halophil), Gram negative rod
endotoxin
a toxin that is present inside a bacterial cell and is released when the cell disintegrates it is sometimes responsible for the characteristic symptoms of a disease
exotoxin
a toxin released by a living bacterial cell into its surroundings.
enterotoxin
exotoxin affecting the intestines - inflame the intestinal lining and inhibit water absorption.
dysentery
large intestinal inflammation
enteritis
inflammation of the intestine often and intoxication - food poisoning
gastritis
inflammation of the stomach
hepatitis
inflammation of the liver
cholecystitis
inflammation of the gallbladder
cholangitis
inflammation of the bileducts
peritonitis
inflammation of the peritoneum
lymphangitis
inflammation of the lymphatic system
Enteric fever:
a systemic disease that begins in the GI tract : the organism invade through the intestine and become systemic=bacteremia
Lyme disease
Borrelia Burgdorferi
black legged or deer tick
flu like symptoms
chronic
target shape rash
Borrela burgdorferi
gram negative spirochete
rickettsia rickettsii
gram NEGATIVE pleomorphic - OBLIGATE intracellular
Rocky mountain spotted fever
rickettsia rickettsii
spread by ticks
flu like symptoms
sudden fever, severe headache, and muscle pain
rash start on extremities and move in pathphneumonic
emerging and reportable disease
Dengue Fever
breakbone fever
emerging disease
vector is mosquito
arbovirus
s/s: high ever, severe bone and joing pain, headache, anorexia and weakness
Anthrax
Bacillus anthracis
Bacillus anthracis
Facultative anaerobic, endospore-forming, Gram positive rod
Francisella tularensis
Gram negative cocco-bacillus
Meningitis
an infection (inflammation) of the layers covering the brain and spinal cord
Bacteria that cause meningitis
Hemophilus influenzae, Streptococcus pneumoniae, Neisseria meningitidis, and Listeria monocytogenes
neisseria meningitidis
gram negative diplo-cocci may be intracelluar
Streptococcus penumoniae
alpha hemolytic
gram postiive diplococci
haemophilus influenzae
gram negative cocco-bacillus
S. Pneumonia
most common cause of meningtis for adults
N. Meningitidis
most common cause of meningitis for teenagers/young adults
Exotoxin
A toxin released by a living bacterial cell into its surroundings
Endotoxin
A toxin that is present inside a bacterial cell and is released when the cell disintegrates
Enteritis
Inflammations of the intestine due to food poising
Dysentery
Large intestine inflammation
What is the difference between inflammatory diarrheal diseases, non-inflammatory diarrheal diseases, secretory, and invasive gastroenteritis?
Inflammatory diarrheal diseases - (AKA dysentery) - Invasion of the intestinal wall with inflammation and a release of leukocytes (+/- erythrocytes) into the intestinal lumen.
Non-inflammatory diarrhea diseases - Bacterial toxin or virus alters the fluid balance in the intestine. Often to to toxicities
Invasive gastroenteritis - *
don't see any information about this in powerpoints
*
What is food intoxication?
- Food intoxication (food poisoning) is a common cause of illness in the US and other countries
- The term "food poisoning" should be reserved for true food intoxications, **where the bacterial TOXINS are ingested - bacteria need not be ingested, or if ingested, need not colonize.
- The bacteria actually multiply in the food and produce toxins, which are ingested.
What's the difference between a food poisoning (toxicity) and an infection acquired from food?
Food poisoning is caused by consuming foods that contain toxins. These toxins can be produced by micro organisms, can occur naturally in the food
A food borne infection is caused by an infectious pathogens (micro organisms that cause infections) in the food
What is diarrhea?
A condition in which feces are discharged from the bowels frequently and in a liquid form.
What is an enterotoxin? Exotoxin? Endotoxin? (review)
Enterotoxins = Exotoxins afferent the intestines - Inflame the intestinal lining and inhibit water absorption
Exotoxin = a toxin released by a living bacterial cell into its surroundings.
Endotoxin = a toxin that is present inside a bacterial cell and is released when the cell disintegrates. It is sometimes responsible for the characteristic symptoms of a disease
What is dysentery?
Large intestinal inflammation - Severe diarrhea, often containing mucous or blood or even pus (Inflammatory)
What is gastritis?
inflammation of the stomach
Enteritis?
inflammation of the intestine
- Most often in the small intestine, and causes diarrhea
- Often an intoxication - Food poisoning
Peritonitis?
Inflammation of the membrane lining the abdominal wall and covering the abdominal organs
Hepatitis?
Inflammation of the liver
Cholecystitis?
Inflammation of the gallbladder
Cholangitis?
Inflammation of the bile ducts
- Treatment (antibiotics) must include removal of causative organism and obstruction
Lymphangitis?
red streaks caused by inflammation of lymphatic vessels in the subcutaneous layer
**Indicative of blood borne infection...a sign of septicemia
What is enteric fever?
Enteric fever is a systemic disease that begins in the GI tract, but may not have any GI symptoms. In enteric fevers, the organisms invade through the intestine and become systemic (Bacteremia).
Enterocolitis - S. typhimurium and S. paratyphi
- Bacteremia following 1-10 day incubation
- Fever and chills
Chronic infections of gallbladder and other tissues possible
- Carrier state established, but eradicated by broad-spectrum antibiotics
Treatment and prevention
- Maintenance of safe food handling conditions and sanitary water
Give some of the normal flora of the blood:
????
What is lymphocytosis?
increase in the number of lymphocytes in the blood.
Leukocytosis?
is white cells (the leukocyte count) above the normal range in the blood.
Leukopenia?
a reduction in the number of white cells in the blood
In which enteric disease is leukopenia common?
Typhoid fever
What is the causative agent of thrush?
Candida albicans
What is septic shock? (Give some causative organisms)
Often nosocomial, with morality of 50-70%
- May occur within 24 hours of invasive medical procedure
- Pseudomonas aeruginosa, Bacteroides fragilis, Klebsiella, Proteus, Serratia, Enterobacter, Escherichia coli ALSO Staph aureus & Strep pneumoniae
- Hypotension, blood vessel collapse, fever, lymphangitis
- **Endotoxin released and antibiotics often cause worsening of the signs
- Diagnosis = Blood culture
- Gram negative septic shock accounts for > 1/3 of all septicemias and most are multiple infections
What is the difference between disease caused by C. perfingens and that caused by C. difficile?
C. difficile can be caused by a nosocomial infection or from antibiotics causing a super infection affecting the GI tract. Can cause Pseudo-Membranous Colitis (PMS)...but only the toxin causes damage. C. perfringens can be cause infections when eating undercooked meat or from a deep wound. Both the toxin AND the organism can cause damage.
What is the pathogenesis of pseudomembranous colitis?
Caused by Clostridium difficile as a consequence of antibiotic therapy causing a super infection.
What is HUS? (Causative agent?)
Hemorrhagic Uremic Syndrome, caused by the Enterohemorrhagic strain of E. coli (EHEC)
Bloody diarrhea
- Found in the intestine of healthy cattle and passed out in manure
- Undercooked hamburger
- Hemorrhagic Uremic Syndrome (HUS)
- **
Major cause of kidney failure in children
- Reportable disease
Why is Escherichia coli important as an indicator organism for contaminated water?
Because E. coli is often found in feces, so it's presence in water shows fecal contamination.
Explain how Helicobacter pylori contribute to the formation of peptic ulcers:
Causes gastritis (inflammation of the stomach) this may weaken the mucous coating of the stomach and duodenum which allows acid to get into the lining beneath. The acid and the bacteria irritate the lining causing an ulcer.
Explain how gallstones can contribute to bacteremia/septicemia:
Formed from crystals of cholesterol and calcium salts which can block the bile ducts and distention (enlarged, swollen from internal pressure) can lead to entry of enteric bacteria (especially E. coli) and passage to the bloodstream (bacteremia)
Septicemia - blood poisoning, especially that caused by bacteria or their toxins
Hepatitis A
- Fecal/oral (contaminated water, shellfish, fast-food)
- Acute, febrile. 15-40 day incubation
- Malaise (uneasy) , headache, nausea, diarrhea, abdominal pain, anorexia (loss of appetite)
- Can cause severe jaundice, but may be asymptomatic
- Fall/winter - Children/young adults
- No animal reservoirs
- Replicates in the GI tract and spreads via blood to liver spleen, other organs
- Vaccine available
- Chronic infection rare and life-long immunity develops
- *Hepatitis A DNA can be present (and detected) in feces, serum, and saliva samples
Hepatitis B
- Fecal-oal route (IV or anal/oral sex), contact with body secretions containing virus, *health care workers
- All ages, anytime
- Incubation 45-180 days
- Replicates in liver, lymphoid tissue and bone marrow, w/ symptoms similar to HAV
- May contribute to liver cancer
- Vaccine available and sexually active persons should be vaccinated
Hepatitis C
- Parenterally (blood-borne)
- Major reason for liver transplants
- Possibly two different agents
- Liver enzymes (alanine transferase - ALT) will be elevated in this diseases vs. the other types
- Chronic infection occurs in ~ 80% of cases w/ 20% of these progressing to cirrhosis and cancer
- No vaccine
Transmission
- Sharing drugs and needles
- Having sex, especially if you have an STD, an HIV infection, several partners, or have rough sex
- Being stuck by infected needles
- Vertical transmission -- a mother can pass it to a child
- Hepatitis C isn't spread through food, water, or by casual contact
Hepatitis D (HDV) - delta hepatitis
Extremely pathogenic
- The delta agent is a viroid (naked RNA - no capsid) enclosed in a hepatitis B virus
- Must be simultaneous infection of a cell with both the hepatitis B virus and the hepatitis D viroid
- Vaccination for HBV will be protective
Which is the chronic form of hepatitis?
Hepatitis C
Which hepatitis virus is pathogenic only in combination with HBV?
Hepatitis D
Which hepatitis virus is considered infectious hepatitis?
Hepatitis A
Which hepatitis virus is considered serum hepatitis?
Hepatitis B
Which forms of hepatitis have vaccines available?
Hepatitis A
Hepatitis B
Hepatitis D (with vaccination from Hepatitis B
What is rheumatic fever? (Causative organism(s)
- Beta hemolytic strep (Streptococcus pyogenes)
- Multi-system disease following infection w/ S. pyogenes (sequelae)
- Ages 5-15 years, generally 2-3 weeks after strep throat
Signs/symptoms -
- Fever, arthritis, mitral valve damage, cutaneous nodules near elbows appear weeks or months later
- Rash - A long-lasting reddish rash that begins on the trunk or arms as macules, which spread outward and clear in the middle to form rings
- Heart damage is due to immune system disorder (Ag-Ab complexes similar to the process of glomerulonephritis)
- At-risk individuals should receive prophylactic antibiotics prior to invasive procedures
- Subcutaneous nodules: Painless, firm collections of collage fibers over bones or tendons
- Commonly appear on the back of the wrists, the outside elbow, and the front of the knees
myocarditis
- Inflammation of the heart muscle itself
Pericarditis
Inflammation of the sac surrounding the heart
- Most frequently viral but...
- Staph aureus = ~40%
- Can have a very high mortality rate
Endocarditis
infection of the heart's inner lining,
- Bacterial endocarditis -
- Infective endocarditis
- Life-thratning inflammation/infection of heart lining and valves
Subacute - *Most common
- Fever, malaise, bacteremia, heart murmur lasting two weeks or more
- Vegetations apparent on the heart valves (usually mitral)
- Generally occurs in individuals > 45 years w/ history of heart valve disease of congenital defects
- *
Most cases due to Strep or Straph, but many microbes possible
- Acute - Life-threatning, rapidly progressive
- THANKFULLY, not all that common
- Destruction of the heart valves and death frequently w/in days.
Vegetation -
- Organisms from another site colonize exposed collagen fibers on the heart valves (Bacteria-fibrin masses)
- Interference w/ normal electrical conduction
- Deformation of heart valves
- Decreased pumping efficiency and possible congestive heart failure
What is sub-acute and acute endocarditis? (Some causative organisms, risk factors, etc.)
Most cases are caused by strep or staph
Subacute - *Most common
- Fever, malaise, bacteremia, heart murmur lasting two weeks or more
- Vegetations apparent on the heart valves (usually mitral)
- Generally occurs in individuals > 45 years w/ history of heart valve disease of congenital defects
- Acute - Life-threatning, rapidly progressive
- THANKFULLY, not all that common
- Destruction of the heart valves and death frequently w/in days.
What is the etiology of anthrax?
Bacillus anthracis
Cutaneous Anthrax
- 90% of all cases
- 2-5 days post-exposure
- Low mortality rate
- Spores introduced through the skin (abrasions or cuts)
- Release of exotoxins, invasion of adjacent tissue and extensive damage produced
Respiratory (Pulmonary) Anthrax
- Almost always fatal regardless of treatment
- Uncommon in humans, except for bioterrorism
- Inhalation of spores w/ germination in the alveolar macrophages
- First symptoms resemble flu-like illnesses, then ease as the organs enters the blood (septicemia), and death occurs in 2-3 days from septic shock
Mediastinal lymph nodes become greatly enlarged
- Pathognomonic for pulmonary anthrax
- No person-to-person spread
Intestinal Anthrax
- Mimics food poisoning
- Mortality rate of 25-50%
- Ulcerations along the alimentary canal
- Septicemia and death
Diagnosis
- Blood cultures or smears of cutaneous lesions
- Serologic tests and DNA
What is transovarian transmission?
Transmit disease-causing pathogens from parent arthropod to offspring arthropod..such as when ticks infect their offspring prior to fertilization with Francisella tularensis, Ricksetta rickettsia, & Brucella spp.
What causes the fever relapses seen in the recurring fever of many of the relapsing fever diseases?
Caused by periodic release of organisms from granulomas into blood such as Francicella spp. & Borrelia spp. These can be transmitted by ticks. Transmission through salivary secretions of the tick
What is the causative organism of Lyme's disease (Gram stain? Morphology?)? What are the arthropod vectors?
Borrelia burdoferi gram negative spirochete. Vectors are ticks
What is the causative organism of Rocky Mountain spotted fever (Gram stain? Morphology?)? What are the arthropod vectors?
Ricksetta rickettsia - GRAM NEGATIVE pleomorphic - Obligate intracellular. Vectors are ticks
What is EBV? Why is it important? How does infectious mononucleosis present?
Epstein-Barr virus, it's a herpes virus so it can be latent.
- Very common cause of sore throat
Mononucleuosis ... causes enlarged spleen
Signs/symptoms of infectious mononucleosis
- Affects many systems
- Acute onset - Incubation is long (30-50 days)
- Headache, fatigue, malaise, sore throat, occur w/in 3-5 days and gradually worsen
- Inflammation of lymphatic tissues
- Abnormal B lymphocytes seen (Lymphocytoisis)
- Hepatomegaly and splenomegaly
- Secondary beta hemolytic Strep infections common
- +/- Myocarditis and glomerulonephritis
- Treatment is bed-ret and treatment of secondary infections
Burkitt's lymphoma -
- Seen mostly in children
- ~6 years after primary infection
- Possibly interaction with malarial parasite, since this disease is more common in parts of Africa with endemic malaria
- +/- Chronic fatigue syndrome
- Etc...especially in immune-compromised patients (AIDS)
What is the causative organism of toxoplasmosis? What is the mode of infection?
Toxoplasma Gondii
- Intracellular protozoan infecting many warm blooded domestic and wild animals
- Invades many different tissue
- Infection usually occurs via contact with cat feces or consumption of raw of under-cooked meat
What is meningitis?
an infection (inflammation) of the layers covering the brain and spinal cord
Causative agents (Bacterial)? Of meningitis
Haemophilus influenza, Streptococcus pneumonia, Neisseria meningitides, and Listeria monocytogenes
What are some of the symptoms/signs of meningitis?
Symptoms include headaches, stiff neck, fever, chills, and vomiting
Also causes tissue necrosis, blood vessel clots, increase CSF pressure, decrease CSF flow, and impaired function of the NS
The difference between viral and bacterial meningitis?
Viral (or aseptic) meningitis is much milder than bacterial meningitis
Symptoms - headache, sometimes a stiff neck, but rarely loss of mental status
Usually self-limiting and non-fatal
Most cases are caused by non-polio enteroviruses although Herpes Simplex Virus 2, on first exposure or occasionally on recurrence, can also cause aseptic meningitis and mumps virus also common cause.
Bacterial meningitis
- Symptoms include headaches, stiff neck, fever, chills, and vomiting
- Also causes tissue necrosis, blood vessel clots, increase CSF pressure, decrease CSF flow, and impaired function of the NS
- Death can occur from shock or other complications
- Most cases re acute, but some can be chronic extensions of other infections (Syphilis, herpes, mumps, or TB)
How are each diagnosed?
(Viral and Bacterial meningitis)
A lumbar puncture is the most useful diagnostic procedure for the diagnosis of meningitis - Check CSF
** Can distinguish between viral and bacterial meningitis, both by it's protein composition (High protein/low glucose in bacterial and both normal in viral) and the presence or absence of white cells and of stainable bacteria, and it is imperative that a CSF exam be done if meningitis is suspected.
What is listeriosis? (Etiology? Mode of transmission?)
Caused by Listeria monocytogenes is transmitted through contaminated food (cantaloupe), trans-placentally, or as a zoonosis, and infects mostly the immune-suppressed and the elderly. Food poisoning .. can possibly cause miscarriage in pregnant women
What is meningococcal meningitis? (Etiology? Mode of transmission?)
Gram negative diplococci- may be intracellular
Neisseria meningitides colonize the nasa-pharynx then spread via blood to the meninges (Especially young, college-aged adults)
- Death due to blood clotting, endotoxic shock and/or massive hemorrhage of the adrenal glands
- Vaccines available and are generally required for college aged, young adults
What is pneumococcal meningitis? (Etiology? Mode of transmission?)
Streptococcus pneumoniae Gram-positive diplococci
usually spread via lung, sinus, ear, or mastoid infections
How is neonatal meningitis transmitted?
Vertically
What is a brain abscess? How is it acquired and treated?
A collection of pus that develops in the brain due to an infection.
they are manifested by focal neurological deficits and can be caused by bacteria which spread and an be caused by many bacteria which spread to the brain either hematogenously from wounds or from an infected site such as the middle ear
- Multi-species infection common (anaerobic and aerobic species)
- Mostly in patients < 40 years or > 50 years
- Infection can grow to compress and impede function of the brain
- Detected by CAT scan or radiographs
Treated by surgical drainage and antibiotic therapy
What are spongiform encephalopathies, and what is the neuroglial cell most commonly affected? (Cause? Signs/symptoms? A few specific important diseases?)
Prion diseases progressive, invariably fatal, conditions that affect the brain and nervous system of many animals, including humans. Astrocytes are produced in large amounts. They are distinguished by long incubation periods, characteristic spongiform changes associated with neuronal loss, and a failure to induce inflammatory response. Caused by prions that can cause proteins to fold
Mad Cow Disease is one example of spongiform encephalopathies.
What is encephalitis? (Cause? Signs/symptoms? Reservoirs? A few specific important diseases?)
Encephalitis is an infection of the cortical (brain) tissues cased by viruses
- Can be caused by many toga viruses or flavivirus
- Viruses invade the CNS through bites or infected mosquitos
- Multiply in skin and spread to lymph nodes
- Viremia with invasion of the CNS
- Manifested by fever, headache, nausea, vomiting, neurological deficits, strange behavior, +/- convulsion, and somnolence
Eastern and western Equine Encephalitis - mosquitoes
West nile virus - Flavivirus
- Bird - mosquito - human
- Encephalitis and/or meningitis
What is West Nile Fever and why is important to you?
A viral infection caused by mosquitos. Important because it could happen to anyone who doesn't properly protect themselves with repellent. There are also no vaccines or medications to protect against it.
What is rabies? (Causative agent? Transmission? Reservoirs? Signs/symptoms? Treatment? Prevention?) *Need to know the virus for this one
Caused by Rhabdovirus (unique bullet-shaped virus) ssRNA negative sense, enveloped w/spikes.
Reservoirs: Raccoons, skunks, bats, foxes, coyotes
Transmission: through saliva of infected animal, occasionally aerosols from caves heavily populated with infected bats
Symptoms/signs
Prodromal stage - Flu-like at first
- Strange sensations around the wound
- Nervousness or sense of impending death
Excitation phase
- Severe neurological symptoms
- Loss of muscle control
- Impaired speech, vision
- Anxiety and apprehension become unbearable
- Hydrophobia appears .... hallucinations agitation, herpersalivation
Paralytic phase
- Weakness, loss of consciousness, death
Rabies treatment:
In the United States, post-exposure prophylaxis consists of a regimen of one dose of immune globulin and four doses of rabies vaccine over a 14-day period. Rabies immune globulin and the first dose of rabies vaccine should be given as soon as possible after exposure. Additional doses or rabies vaccine should be given on days 3,7, and 4 after the first vaccination.
Prevention: Take precautions when dealing with reservoirs & get pets vaccinated.
What is poliomyelitis? (Causative agent? Transmission? Reservoirs? Signs/symptoms? Treatment? Prevention?)
Poliomyelitis - Picornavirus
- Positive sense RNA w/three serotypes (1,2,3)
- Have an affinity for the motor neurons of the brain and spinal cord
- High fever, back pain, muscle spasms, paralysis (temporary or permanent)
- Nature/degree of paralysis depends on which neurons are affected and how secretly they're infected
- Most cases are mild and non-paralytic
- Transmission is fecal oral route and from pharyngeal secretions
- Symptomatic treatment
- Humans are the only natural host
Almost completely eradicated in this country except for people unprotected by vaccination
What is tetanus? (Causative agent? Transmission? Reservoirs? Signs/symptoms? Treatment? Prevention?)
Tetanus -
- Clostridium tetani - Obligate anaerobic, motile (peritrichous flagella), spore forming, Gram positive rod
- Endospores are very resistant to heat, drying, cold, etc.
- Found in soil, especially that enriched with manure
- Vaccination (DPT) has reduced the incidence, but incidence is higher in olde women
- Spores deposited in deep tissues of puncture wounds or cuts (anaerobic conditions necessary)
- Organisms remain at the site and release pathogenic exotoxin (tetanospasmin)
- One of the most potent toxins know enters the blood and is carried to the CNS
Signs/symptoms begin after 4-10 days incubation
- Generalized muscle stiffness (rigid paralysis), spasms affecting every muscle
- Toxin inhibits the inhibiting neurons causing continuous contraction
- Arched back (opisthotonos), clenched jaw (truisms), clenched fists, paralysis of respiratory muscles with death imminent
Prevention - Vaccination with tetanus toxoid vaccine
Treatment - Anti-toxin, antibodies and supportive therapy
Tetanus neonatorum - Umbilical cord-acquired tetanus
*Immunization of pregnant women can prevent this disease
What is botulism?
Botulisms -
Clostridium botulinum - Obligate anaerobic, motile (peritrichous flagella), spore forming, Gram positive rod
Releases very potent exotoxin (neurotoxin)
Toxin formation depends on infection with a bacteriophage
**Affects the peripheral nervous system
Acts at the neuromuscular junction to stop release of acetylcholine resulting in a flaccid (limp) paralysis
Death is due to paralysis of respiratory muscles
- Most potent toxin known
- Colorless, odorless, tasteless
- Not a true exotoxin
Food-borne -
- 90% of cases
- Food poisoning (ingestion of toxin)
- Most from improperly canned non-acidic foods (C. botulinum doesn't grow in acidic conditions)
- Heating destroys the toxin but it must be for a sufficient amount of time
Infant botulism -
- Associated w/ feeding honey to babies
- Spores will vegetate in GI tract of infants (causing a true infection and not just a toxicity)... In other words, it can be transmitted through the fecal/oral route as well as ingestion of honey
- Toxin is absorbed causing flaccid paralysis = "floppy baby" syndrome
Wound botulism -
- Occurs in deep crushing wounds allowing endospores to germinate, multiply and produce toxin
- Progressive paralysis
**Know the difference between flaccid and rigid paralysis
Flaccid Paralysis - Caused by botulism
Rigid Paralysis - Caused by tetanus
Intestinal Anthrax....
[ ] Causes a secretory diarrhea
[ ] Shows an inflammatory diarrhea
[ ] Is a true infection
[ ] All of the above
[ ] Both b and c
Both b and c
A vector is best described as a(n)...
[ ] Non-living carrier of microbes (famine)
[ ] Living carrier of pathogens (usually an arthropod)
[ ] Reservoir and source of infection
[ ] Definitive host
[ ] Intermediate host
Living carrier of pathogens (usually an arthropod)
A reservoir of infection is ...
[ ] A source of infectious agent
[ ] The same as a vector
[ ] Must be a living source
[ ] Must be a non-living source
[ ] The same as fomite
A source of infectious agent OR Must be a non-living source
Anthrax is ...
[ ] Infectious and contagious
[ ] Non-infectious and contagious
[ ] Infections and non-contagious
[ ] Non-infectious and non-contagious
[ ] All of the above
Infections and non-contagious
Bacillus spp. are
[ ] Gram positive rods
[ ] Gram positive cocci
[ ] Gram negative rods
[ ] Gram negative diplococci
[ ] Acid-fast rods
Gram positive rods
Streptococcus pyogenes is a(n)
[ ] Gram negative cocci in clusters
[ ] Gram positive coccobacillus in chains
[ ] Gram positive cocci in chains
[ ] Gram negative diplococci, often intracellular
[ ] Gram positive bacillus in clusters
Gram positive cocci in chains
Reportable (or notifiable) diseases require...
[ ] That the patient tell everyone who ate the food
[ ] The local health department must be contacted
[ ] All sex partners must be contacted by the patient
[ ] The CDC should be notified immediately
[ ] All of the above
The local health department must be contacted
True or false: Food-borne illnesses are reportable diseases
[ ] True
[ ] False
True
Sharon has chronic urinary tract infections, so the last time she was at her doctors office she asked for amoxicillin prescription "just incur". Why is this a bad idea?
[ ] She might become resistant to the medication
[ ] The microbes could be resistant to the medication
[ ] It could kill normal flora prompting a super infection
[ ] All of the above
[ ] Both b and c
Both b and c
Gamma hemolysis is ...
[ ] Complete hemolysis of the RBCs by the bacteria causing a clear halo around the colonies
[ ] Partial hemolysis of the RBCs by the bacteria causing a greenish halo around the colonies
[ ] No growth of bacteria on the blood agar
[ ] No hemolysis of the RBCs by the bacteria, causing no change in the agar around the colonies
[ ] Bacterial colonies appear yellowish on the agar
No hemolysis of the RBCs by the bacteria, causing no change in the agar around the colonies
Septicemia is ...
[ ] Bacteria in the blood
[ ] Microorganisms in the blood
[ ] Blood infection
[ ] Viruses in the blood
[ ] All of the above
All of the above
Protozoal organisms are ...
[ ] Fungi
[ ] Prokaryotes
[ ] Diagnosed by looking for hyphae
[ ] Eukaryotes
[ ] Members of the domain Bacteriaciae
Eukaryotes
A reportable disease must be...
[ ] Reported to the hospital administrator
[ ] Tracked by the health care facility
[ ] Reported to the health department
[ ] Mentioned to the patient
[ ] Reported to the government (CDC)
Reported to the health department
A patient with Legionnaire's disease should be isolated from other hospitalized patients ...
[ ] Yes. The disease is extremely contagious
[ ] No. There's no person-to-person transmission
[ ] Yes. It's good practice at all times
[ ] No. They're gonna die anyway
[ ] Yes. In fact they should be quarantined
No. There's no person-to-person transmission
To select for enteric microbes, the best media to use would be
[ ] MacConkey's agar
[ ] Eosin Methylene Blue agar
[ ] Bile Esculin agar
[ ] All of the above
[ ] Both a and b
All of the above
Escherichia coli is a(n) ...
[ ] Gram + cocci
[ ] Gram - rod
[ ] Acid fast rod
[ ] Gram + rod
[ ] Eukaryotic cell
Gram - rod
Sets found in the same folder
BI203 Unit 1 Exam
58 terms
FINAL MICROBE COMPLETED LIST LORD GIVE M…
57 terms
Other sets by this creator
tree
32 terms
Strictly Rhythms
60 terms
Remember This
233 terms
NCLEX FINAL SET YOU BETTER PASS THIS YOU…
635 terms
Recommended textbook solutions
Human Resource Management
15th Edition
•
ISBN: 9781337520164
John David Jackson, Patricia Meglich, Robert Mathis, Sean Valentine
249 solutions
Clinical Reasoning Cases in Nursing
7th Edition
•
ISBN: 9780323527361
Julie S Snyder, Mariann M Harding
2,512 solutions
Hole's Human Anatomy and Physiology
15th Edition
•
ISBN: 9781259864568
(4 more)
David Shier, Jackie Butler, Ricki Lewis
1,952 solutions
Body Structures and Functions
12th Edition
•
ISBN: 9781133691655
Ann Senisi Scott, Elizabeth Fong
830 solutions
Other Quizlet sets
Cell Bio Ex 3
108 terms
ROW test 1
19 terms
Civics Exam Review
88 terms
Pharm- Sympathetic Antagonists
38 terms