Microbiology, Ch 25, Nester's 9th

The circulation of an agent in the bloodstream is given a name ending in -ase. -ing. -emia. -ation.

-emia.

Vocab quiz - don't even know where some of these came from.

20/20

Yellow fever is transmitted by ticks. fleas. Anopheles mosquitoes. Aedes mosquitoes.

Aedes mosquitoes. Bunch of viruses from mosquitoes - Yellow fever - main vector = Aedes aegypti mosquito - Dengue fever - main vector = Aedes aegypti and Aedes albopictus - Chikungunya - Aedes aegypti and Aedes albopictus mosquitoes - Zika - Aedes aegypti and Aedes olbopictus (less frequently) Anopheles mosquitoes carry Plasmodium for Malaria. Fleas is Yerisinia pestis and plague. Ticks is Lyme disease - but Ebola and Marburg - fruit bats reservoir

Which of the following is more likely to cause fatal septicemias? Gram-positive bacteria Gram-negative bacteria negative stained bacteria acid-fast stained bacteria

Gram-negative bacteria Systemic infection by any microorganism can cause sepsis- more than 50% of cases are caused by Gram-positives but most fatal cases involve Gram-negatives because of the LPS (endotoxin) in their outer membrane.

Which one of the following is NOT a zoonosis? cat-scratch disease Hantavirus pulmonary syndrome rabies tapeworm None of the answers is correct; all of these are zoonoses

None of the answers is correct; all of these are zoonoses

The virulence factor of Yersinia pestis that is a protease that destroys C3b and C5a is Yops. PLA. F1. protein A.

PLA. Table 25.3/p.670 - Pla (protease) activates plasminogen, destroys C3b, C5a and clots (allows bacteria to spread) - Once Y. pestis enters via a flea bite, it releases a protein-degrading protease (Pla) that clears the lymphatics and capillaries of clots and inactivates certain complement system components, allowing the organism to spread - goes to lymph nodes, gets taken up by macrophages.

Which of the following statements regarding Vibrio vulnificus infections in FALSE? The causative agent of the disease, V. vulnificus, is a Gram-negative halophile. People consuming V. vulnificus typically develop signs and symptoms of gastroenteritis. V. vulnificus causes different signs/symptoms, depending on the portal of entry. Liver disease increases the risk of developing severe illness with V. vulnificus infections. People with V. vulnificus infection always develop life-threatening sepsis.

People with V. vulnificus infection always develop life-threatening sepsis. - Is a halophile - seafood right? So tolerates sea water. Salty. - when ingested, an otherwise healthy person may develop only a self liming case of gastroenteritis. - Signs and symptoms do depend on the portal of entry (mouth/open wounds). - in a person with liver disease, the bacteria may invade the bloodstream, leading to fevers, chills, severe skin blistering and shock due to sepsis, which is often fatal. - nope! can be self-limiting or more severe. Depends.

How would crowded conditions in cities favor spread of bubonic plague? Plague is transmitted by mosquitoes; more people close together gives an infected mosquito more chances to bite humans and transmit the causative agent, spreading plague. Plague is transmitted by infected fleas; these fleas may be found on rodents (such as rats). More people in an area means a greater chance of interactions with animals carrying infected fleas, increasing the spread of plague. Plague is transmitted by rats; more people means more waste, and more waste means more rats. This would favor the spread of plague. Plague is transmitted by direct contact (e.g. skin to skin). More people in an area provides more chances for infected individuals to directly contact and infect other individuals, spreading plague. Bubonic plague is transmitted by aerosol droplets. People in cities are always dependent on public transport, which is typically overcrowded, so are at risk of acquiring plague bacteria.

Plague is transmitted by infected fleas; these fleas may be found on rodents (such as rats). More people in an area means a greater chance of interactions with animals carrying infected fleas, increasing the spread of plague. Correct Plague - fleas - rats.

The causative agent of plague is Vibrio cholerae. Staphylococcus aureus. Brucella abortus. Yersinia pestis.

Yersinia pestis. Y. pestis is a member of Enterobacteriaceae - is a facultative anaerobe, Gram negative rod that grows best at 28C, is non-motile and forms biofilms in flea guts

The sac which surrounds the heart is called the endocardium. pericardium. atrium. myocardium.

pericardium. peri- = around endocardium is lining inside heart atrium is heart chamber myocardium is heart muscle

The "Black Death" may also be known as tularemia. brucellosis. endocarditis. plague.

plague.

The disease responsible for the death of approximately ¼ the population of Europe from 1346 to 1350 was typhus. pneumonia. influenza. plague.

plague. Crowded conditions and a large rat population had major roles in the spread of plague. Plague is a potential bioterrorism disease, Category A.

High levels of antibodies in patients with SBE tend to be of little use because they make the bacteria clump together and adhere to the clot. the surface antigens change rapidly and become unrecognizable. the antibodies are defective. the antibodies degrade quickly.

they make the bacteria clump together and adhere to the clot. Microbes adhere to heart tissue, multiply, create a biofilm, the clot grows larger around the multiplying organisms, building up a fragile mass. Bacteria get washed off the mass into the bloodstream and pieces of infected clot (septic emboli) can break off. p.667 actually says antibodies will complex with antigens and immune complexes may lodge in body structures and trigger an inflammatory response. Says microbes adhere to heart tissue, multiply, create a biofilm, the clot grows larger around the multiplying organisms, building up a fragile mass. Bacteria get washed off the mass into the bloodstream and pieces of infected clot (septic emboli) can break off.

High levels of antibodies in patients with infectious endocarditis cause inflammation because they may form clots that lead to life-threatening emboli. the surface antigens change rapidly and become unrecognizable. they may form immune complexes that get trapped in skin and eyes. the antibodies initiate type I, type II, or type III hypersensitivities. the antibodies degrade quickly and debris gets trapped in these organs.

they may form immune complexes that get trapped in skin and eyes. p.667 Correct

The stage of Lyme disease that is characterized by arthritis is the fourth. third. second. primary. intermediate.

third p.672 - the third stage of Lyme disease (Late persistent infection) is characterized by ARTHRITIS and the affected joints have high concentrations of reactive immune cells and immune complexes. Correct

Yersinia pestis typically contains one plasmid. two plasmids. three plasmids. four plasmids.

three plasmids.

The major virulence factors of Yersinia pestis are carried on the chromosome. a plasmid. three separate plasmids. nuclear membrane.

three separate plasmids. Nothing in my chapter says anything about plasmids.

Subacute bacterial endocarditis is usually caused by bacteria: - trapped in thin blood clots on a deformed heart valve and multiplying very rapidly. - trapped in thin blood clots on a deformed heart valve and multiplying slowly. - attaching to and colonizing the walls of the atria of the heart, multiplying very rapidly. - attaching to and colonizing the ventricles of the heart, multiplying slowly.

trapped in thin blood clots on a deformed heart valve and multiplying slowly. Slowly - subacute happens more gradually. Acute - happens rapidly.

Bacteria which cause subacute bacterial endocarditis may gain access to the bloodstream by trauma. dental procedures. brushing teeth. ingestion. trauma, dental procedures AND brushing teeth.

trauma, dental procedures AND brushing teeth. p.667 - The bacteria the cause infective endocarditis may enter the bloodstream from another infected body site or during DENTAL PROCEDURES, TOOTH BRUSHING, OR TRAUMA.

Enlargement of lymph nodes or spleen is often associated with tularemia. brucellosis. plague. gastritis. tularemia, brucellosis AND plague.

tularemia, brucellosis AND plague. p.669 - plague - characteristically develop significantly enlarged and tender lymph nodes called BUBOES. p.675 - tularemia - regional lymph nodes enlarge p.676 - brucellosis - patients complain of mild fever, sweating, weakness, aches and pains, enlarged lymph nodes...

You go hiking in the woods with some of your classmates. A few days after the hike, your friend Alice calls to tell you she is not feeling well and that she is going to skip soccer practice that evening. She says she has a weird rash on her leg and wonders if she was bitten by a spider while your were hiking. She sends you a photo of the rash. You are in your final semester of nursing school and have recently studied disease of the cardiovascular system. You think that the rash that Alice has is a sign of Lyme disease, and offer to take her to the urgent care to get medical help. While you are waiting to see a clinician, you review answer Alice's questions about Lyme disease.What causes the characteristic erythema migrans of Lyme disease? Borrelia bergdorferi is an encapsulated organism. The capsule of these cells is composed of hyaluronic acid that causes a widespread inflammatory response in the skin of the host that manifests as a rash. Borrelia bergdorferi cells propel themselves from host cell to host cell using actin tails, in a manner similar to Shigella cells. As they move, the bacteria destroy the host cells, causing the characteristic rash. After being introduced into the skin by the bite of an infected mosquito, the Gram-positive bacteria migrate outward in a corkscrew-like manner; the NAGs and NAMs in their cell wall causes an inflammatory reaction. After a person acquires the causative bacteria by eating contaminated meat, the bacteria migrate to the skin in a corkscrew-like motion, killing host cells as they move and causing the bull's-eye rash. After being introduced into the skin by the bite of an infected tick, the Gram-negative bacteria migrate outward in a circular manner; the LPS in their outer layer causes an inflammatory reaction.

After being introduced into the skin by the bite of an infected tick, the Gram-negative bacteria migrate outward in a circular manner; the LPS in their outer layer causes an inflammatory reaction. p.672 Correct

The scientist responsible for the development of the first anti-plague vaccine in 1866 was Alexandre Yersin. Robert Koch. Louis Pasteur. Josef Marburg.

Alexandre Yersin p.664 - Yersin studies plague - reported discovery of a bacillus (rod) always present in swollen lymph nodes of plague victims. Could be cultivated, made rats sick and they made other rats sick. Yersin's plague bacillus was named Yersinia pestis, used to make a VACCINE and then an antiserum - led to first successful treatment of a plague victim.

Enlargement of lymph nodes or spleen is often associated with tularemia. brucellosis. plague. infectious mononucleosis. All of the choices are correct.

All of the choices are correct.

In which of the following diseases does the spleen enlarge? infectious mononucleosis malaria leishmaniasis brucellosis All of the choices are correct.

All of the choices are correct.

Traditionally the animal(s) associated with hosting Brucella is/are cattle. dogs. goats. pigs. All of the choices are correct.

All of the choices are correct. - domestic animals. Brucellosis melitensis if people but there are others: Brucellosis abortus infects cattle Brucellosis canis infects dogs Brucellosis melitensis infects goats Brucellosis suis infects pigs

Blood and lymph may carry antibodies. complement. lysozyme. interferon. All of the choices are correct.

All of the choices are correct. Antibodies = duh complement are blood proteins p.655 - Blood and lymph both carry infection-fighting leukocytes and antimicrobial proteins, including ANTIBODIES, COMPLEMENT, LYSOZYME AND INTERFERON. Correct

Which of the following is/are the modes of transmission for T. francisella? Via ingestion of contaminated meat By tick bites Through minor cuts or abrasions By inhalation All of these

All of these p.675/676 Correct

Epstein-Barr virus may become latent in red blood cells. T cells. nerve cells. B cells.

B cells. p.678 - infects mouth/throat (pharyngitis), carried to lymph nodes and infects B cells (mononuclear cells) - infection can be Productive (virus replicates and kills the B cell) or Non-Productive (latent infection as provirus or plasmid).

What is the difference between 'bacteremia' and 'septicemia?' Bacteremia is an infection with bacteria. Septicemia is an infection with Septic protozoans. Bacteremia is the presence of living, multiplying bacteria in the bloodstream. Septicemia is the presence of endotoxins, but not necessarily of living microbial agents. Septicemia is the presence of living, multiplying bacteria in the bloodstream. Bacteremia is the presence of endotoxins, but not necessarily of living microbial agents. There is no difference-both terms denote the presence of living bacterial cells in the bloodstream.

Bacteremia is the presence of living, multiplying bacteria in the bloodstream. Septicemia is the presence of endotoxins, but not necessarily of living microbial agents.

Brucellosis may also be known as Bang's disease. undulent fever. Hansen's disease. rabbit fever. Bang's disease AND undulent fever.

Bang's disease AND undulent fever. p. 676 - Because Bang discovered the cause of cattle brucellosis and the fevers are rucurrent over weeks or months.

You go hiking in the woods with some of your classmates. A few days after the hike, your friend Alice calls to tell you she is not feeling well and that she is going to skip soccer practice that evening. She says she has a weird rash on her leg and wonders if she was bitten by a spider while your were hiking. She sends you a photo of the rash. You are in your final semester of nursing school and have recently studied disease of the cardiovascular system. You think that the rash that Alice has is a sign of Lyme disease, and offer to take her to the urgent care to get medical help. While you are waiting to see a clinician, you review answer Alice's questions about Lyme disease. Lyme disease is a zoonosis with humans being an accidental host. What does this mean? Borrelia bergdorferi is transmitted to animals from humans AND the bacterium cannot complete its life cycle in humans. Borrelia bergdorferi is found predominantly in zoo animals AND the tick vector cannot complete its life cycle in humans. Borrelia bergdorferi is found predominantly in zoo animals AND the bacterium cannot complete its life cycle in humans. Borrelia bergdorferi is found predominantly in zoo animals AND humans are not the normal host for the tick vector. Borrelia bergdorferi is transmitted to humans from animals AND humans are not the normal host for the tick vector.

Borrelia bergdorferi is transmitted to humans from animals AND humans are not the normal host for the tick vector. Correct Borrelia burgdorferi - bacteria- Gram negative, microaerophilic spirochete with many plamsids and a chromosome that is linear and present in multiple copies

Which of the following is/are able to survive phagocytosis? Brucella sp. Staphylococcus aureus Francisella tularensis Mycobacterium tuberculosis Brucella sp, Francisella tularensis AND Mycobacterium tuberculosis

Brucella sp, Francisella tularensis AND Mycobacterium tuberculosis Brucellosis - Brucella sp. prevent phagosome-lysosome fusion Tularemia - Francisella tularemia escape from the phagosome TB - Mycobacterium tuberculosis - mycolic acids in the bacterial cell wall prevent phagosome-lysosome fusion, bacteria leaves the phagosome, multiplies in cytoplasm. p.553

How does F. tularensis avoid the immune system? By escaping from the macrophage phagolysosome AND by producing streptokinases. By having altered surface components AND by destroying lymphocytes. By synthesizing a large polysaccharide capsule AND by escaping the macrophage phagolysosome. By having altered surface components AND by escaping the macrophage phagolysosome. By synthesizing a large polysaccharide capsule AND by degrading complement component C3b.

By having altered surface components AND by escaping the macrophage phagolysosome. p.676 Correct

Which organism may be implicated in arteriosclerosis? Escherichia coli Pseudomonas aeruginosa Chlamydia pneumoniae Staphylococcus aureus

Chlamydia pneumoniae No idea where this comes from. Correct

Two people are brought to the Emergency Department where you work. The first patient reports fever, abdominal pain, vomiting, and diarrhea. The second patient appears extremely ill. Her family tells you that she also had gastrointestinal signs and symptoms a few days ago. She has now developed severe skin blistering, has a very high fever and is only semi-conscious. When you question the first patient and the family of the second patient, you discover that they know each other and that they have all recently returned from a beach vacation in a major city on the U.S. Gulf Coast. The group tells you that the enjoyed a raw oyster dinner on the last day of their summer vacation. They think that both patients are probably just allergic to seafood, but given the severity of the signs and symptoms of your patients, you suspect that they may have Vibrio vulnificus infection. Lab tests confirm your suspicion. You give the families information on this disease.You find out that the seriously ill patient has an underlying condition. Which of the following likely predisposed her to the more severe infection? Cystitis Asthma Glomerulonephritis Osteoporosis Cirrhosis

Cirrhosis Liver problem. p.674 Correct

The cause of infectious mononucleosis is varicella virus. Staphylococcus aureus. Epstein-Barr virus. Francisella tularensis.

Epstein-Barr virus. - enveloped, dsDNA virus of family Herpesviridae, no relation.

Gram-positive organisms are more likely to cause fatal septicemias than other infectious agents. T/F

False

Septicemia is only caused by Gram-negative bacteria. T/F

False - It can be cause by any bacteria that gets into the bloodstream. More Gram positives cause sepsis but cases from Gram negatives are worse.

Yellow fever is caused by a protozoan infection. T/F

False but malaria is!

What leads to organ failure in sepsis? Helper T cells and dendritic cells undergo apoptosis, causing immunosuppression that results in organ rejection. Uncontrolled inflammation that leads to neutrohpils releasing damaging toxins and lysosomal enzymes. Formation of small clots in capillaries, impairing blood flow to organs and causing hypoxia and cell death. Accumulation of endotoxins released from Gram-negative bacteria in the organs, causing tissue damage and cell death. Organisms from an infected site generate biofilms that break apart, leading to emboli and organ destruction.

Formation of small clots in capillaries, impairing blood flow to organs and causing hypoxia and cell death. p.668 Correct

When Lyme disease was first being investigated, the observation that frequently only one person in a household was infected was a clue leading to the discovery that the disease was transmitted by arthropod bites. Why was this so? Mosquitoes (an example of arthropods) are never inside a house. They are strictly outdoor insects, so they couldn't spread the infection inside the household. If the infection is spread by the bite of an arthropod, it wouldn't spread easily by respiratory secretions, direct contact, or sexual contact between individuals within the family. Mosquitoes (an example of arthropods) only bite once in their lifetime. As such, they can only transmit the illness once before they die. Even if an infected mosquito was inside a house, it could only infect one human. Arthropods lose their mechanical ability to bite a human after a single bite, much like certain bees lose their stinger after a single sting. This prevents them from transmitting the infection to more than one individual in a household. These are all valid reasons that support the theory that Lyme disease must be transmitted by arthropod bites.

If the infection is spread by the bite of an arthropod, it wouldn't spread easily by respiratory secretions, direct contact, or sexual contact between individuals within the family. Read them. The rest are stupid. Correct

Which of the following is NOT a route by which bacteria that cause infective endocarditis may gain access to the bloodstream? Ingestion Brushing teeth Trauma Dental procedures Kidney infection

Ingestion p.667 - The bacteria the cause infective endocarditis may enter the bloodstream: - from another infected body site - during dental procedure - during tooth brushing - from trauma Correct

Endocarditis - Inflammation of the heart valves or lining of the heart chambers. Fungemia - Fungi circulating in the bloodstream. Gametocyte - Haploid cell that can be used for sexual reproduction. HIV (viral) set point - Viral load in a person with HIV disease after the immune system begins to respond to the virus and viral numbers stabilize. Human immunodeficiency virus, HIV - The virus causing a disease marked by gradual impairment of the immune system, culminating in AIDS. Reverse transcriptase - Enzyme that synthesizes double-stranded DNA complementary to an RNA template. Seroconversion - Change from serum that lacks specific antibodies to serum that has those antibodies. Subacute bacterial endocarditis - Slowly progressing infection of the internal surfaces of the heart. Transformation - Morphologic and physiologic changes making a cell cancerous resulting from infection of an animal cell by an oncogenic virus. Trophozoite - Vegetative feeding form of some protozoa. Disseminated intravascular coagulation, DIC - Devastating condition in which clots form in small blood vessels, leading to failure of vital organs.

Integrase - Enzyme encoded by HIV or another retrovirus that inserts the DNA copy of the viral genome into a host cell chromosome. Kaposi's sarcoma - Tumor arising from blood or lymphatic vessels. Paroxysm - A sudden increase in symptoms. Petechiae - Small purplish spot on the skin or mucous membrane caused by hemorrhage. Preventive vaccine - Vaccine that prevents a disease. Acquired immune deficiency syndrome, AIDS - A disease of the human immune system caused by infection with human immunodeficiency virus (HIV); the most advanced stage of infection with HIV. Acute retroviral syndrome, ARS - A stage of HIV disease following the incubation stage; often includes flulike symptoms. Bacteremia - Bacterial cells circulating in the bloodstream. Bubonic plague - Form of plague that typically develops when it is injected during the bite of an infected flea.

Which is NOT a reason that it would be more difficult to eradicate Lyme disease than rubeola or rubella? Rubeola and rubella only infect humans—if all humans were immune (through vaccination for example), the diseases would be eliminated. The causative agent of Lyme disease is harbored in intermediate hosts (mice and deer)—elimination of these would be impossible. Lyme disease is transmitted by Ixodes tick vectors—it would be impossible to eliminate these ticks from earth. Lyme disease is cannot be treated successfully with antimicrobials, while rubella and rubeola can be successfully treated—it is thus easier to eliminate them. These are all valid reasons to explain why eradicating Lyme disease would be more difficult than eliminating rubella and rubeola.

Lyme disease is cannot be treated successfully with antimicrobials, while rubella and rubeola can be successfully treated—it is thus easier to eliminate them. This is NOT a reason because Lyme disease can be treated with antimicrobials. CORRECT!

Select the statement about plague that is TRUE. DIC causes the dusky color of skin and mucous membranes characteristic of bubonic plague. When Yersinia pestis infects the lungs, septicemic plague always develops. The causative agent of plague is a facultatively anaerobic, Gram-positive rod. Bubonic plague is transmitted by the bite of infected mosquitoes that have also bitten rats. Bubonic plague is almost always fatal.

Maybe the first one. - that's septic plague - not always - facultative anaerobe, G-, not + - bite of infected fleas - 50-80% fatal is not treated... but it is treatable so NOPE (tried, it was wrong)

Which of the following virulence factors of Yersinia pestis aid(s) in attachment to host cells? Endotoxin Pla PsaA Yersinia outer proteins (Yops) V antigen

PsaA p.670/Table 25.3 endotoxin = no Pla is about clearing the way to spread Yops is about inhibiting phagocytosis V antigen controls the type III secretion system that delivers the Yops to host cells. PsaA = adhesin - role in ATTACHMENT to host cells. Correct

Which of the following statements regarding sepsis and septic shock is TRUE? - Sepsis can be prevented with an attenuated vaccine. - Sepsis initially starts due to an overstimulation of the inflammatory response. - A patient surviving the initial stages of sepsis will always recover fully. - Sepsis and septic shock are always caused by Gram-negative bacteria.The signs and symptoms of sepsis include drop in urine output and dusky skin color. - Sepsis and septic shock are easily treated by administering combinations of antibiotics.

Sepsis initially starts due to an overstimulation of the inflammatory response. Problems with each of the other statements.

Why might the Yersinia pestis from a patient with pneumonic plague be more dangerous than the same organism from fleas? The organism acquired this way is already fully virulent, so is especially dangerous. The organism mutates in a person with pneumonic plague, so is more dangerous. The organism involved in pneumonic plague is resistant to multiple antibiotics. Y. pestis in the lungs has a polysaccharide capsule while that in fleas does not. These are all true.

The organism acquired this way is already fully virulent, so is especially dangerous. p.670 Correct

Why does it take more than a week before a mosquito that has just become infected with yellow fever virus can transmit the disease? Mosquitoes only feed once a week, which limits their ability to transmit the disease rapidly. The mosquito actually transmits the virus almost immediately. It takes a week for the virus to multiply in the gut of the host before it causes any ill effects in that host. The virus multiplies in the gut of the mosquito, but then needs to migrate to the mouth of the insect in order to infect a new human being after a new bite. This migration takes time. Mosquitoes that acquire yellow fever virus become ill for a week thereafter. They have to recover before they can feed again and transmit the virus to the next host. The virus must replicate in the gut of the mosquito before it can reach high enough numbers for transmission to a new human.

The virus must replicate in the gut of the mosquito before it can reach high enough numbers for transmission to a new human. Correct

What is the significance of immune complex formation in infective endocarditis? They lead to the formation of biofilms that are difficult to eliminate. They cause disseminated intravascular coagulation. They result in the enzymatic destruction of neutrophils and macrophages. They lead to the development of autoimmunity. They can be deposited in tissues and organs, causing damage.

They can be deposited in tissues and organs, causing damage. p.667 Correct

Which of the following can only be identified using PCR after valve surgery? Escherichia coli Staphylococcus aureus Tropheryma whippelii Staphylococcus epidermidis

Tropheryma whippelii The other 3 are able to be cultivated in vitro. Apparently it causes a systemic disease called Whipple's disease...

Borrelia burgdorferi is a microaerophilic spirochete. T/F

True

Both malaria and yellow fever are transmitted by mosquitoes. T/F

True

Muscles aid the flow of venous blood. T/F

True

Plasmodium falciparum causes the most serious form of malaria. T/F

True

The media used to successfully grow Francisella tularensis must contain cysteine. T/F

True

The major virulence factors of Yersinia pestis are carried on a plasmid. T/F

True Apparently on 3 of them.

Both Francisella tularensis and Mycobacterium tuberculosis are able to survive phagocytosis. T/F

True Brucella sp, Fransicella tularemia and Mycobacterium of TB can.

In a malarial infection, only sporozoites can infect the human liver.

True This is why malaria/Plasmodium sp. spread by drug abuse is easier to treat - its just the infection of blood cells, you need the sporozoites from the mosquito bite to infect the liver cells. - bite (sporozoites carried to liver, infect hepatocytes), multiply and change into merozoites that get released into blood stream and infect RBCs, develop into larger motile trophozoite (feeding form), then schizont (reproducing stage) that gives rise to merozoites that get releaesed and infect more RBCs. Some merozoites from gametocytes instead of schizonts and need to be ingested by mosquitoes to become gametes, zygotes and mature into oocysts that release sporozoites into mosquito mouth bits and saliva.

When a person becomes infected with the Epstein-Barr virus (EBV), a member of the herpesvirus family, they are infected for life. They may occasionally suffer reactivation events that may make them infectious to other individuals once again. T/F

True p.679 - EBV is present in saliva for up to 18 months after infectious mononucleosis and then intermittently for LIFE.

Two people are brought to the Emergency Department where you work. The first patient reports fever, abdominal pain, vomiting, and diarrhea. The second patient appears extremely ill. Her family tells you that she also had gastrointestinal signs and symptoms a few days ago. She has now developed severe skin blistering, has a very high fever and is only semi-conscious. When you question the first patient and the family of the second patient, you discover that they know each other and that they have all recently returned from a beach vacation in a major city on the U.S. Gulf Coast. The group tells you that the enjoyed a raw oyster dinner on the last day of their summer vacation. They think that both patients are probably just allergic to seafood, but given the severity of the signs and symptoms of your patients, you suspect that they may have Vibrio vulnificus infection. Lab tests confirm your suspicion. You give the families information on this disease.People with chronic liver disease frequently have elevated levels of iron in their blood. Iron is needed by V. vulnificus for growth. How does it acquire iron from the host? V. vulnificus produces a hemolysin that lyses blood cells to release iron-containing hemoglobin. V. vulnificus produces a hemolysin that lyses white blood cells to release iron-containing hemoglobin AND it produces transferrins that allow it to scavenge iron. V. vulnificus produces a hemolysin that lyses white blood cells to release iron-containing hemoglobin AND it produces lactoferrins that allow it to scavenge iron. V. vulnificus produces a hemolysin that lyses blood cells to release iron-containing hemoglobin AND it produces siderophores that allow it to scavenge iron. V. vulnificus produces siderophores that allow it to scavenge iron.

V. vulnificus produces a hemolysin that lyses blood cells to release iron-containing hemoglobin AND it produces siderophores that allow it to scavenge iron. p.674 Correct

Which statement about the cardiovascular and lymphatic systems is NOT true? The cardiovascular and lymphatic systems are typically sterile. Phagocytes in spleen red pulp remove aging or damaged RBCs, bacteria, and other antigens from the blood. Blood is exposed to immune cells as it passes through the spleen. Veins carry blood away from the heart while arteries carry blood towards the heart. Inflammation of lymphatic vessels is called lymphangitis, which presents as a red streak from an infection site toward the nearest lymph node.

Veins carry blood away from the heart while arteries carry blood towards the heart. Arteries carry blood away, veins carry blood to the heart. Correct

The plague bacillus is known as Plasmodium vivax. Pneumocystis carinii. Streptococcus pyogenes. Yersinia pestis.

Yersinia pestis. Yersinia pestis - member of Enterobacteriaceae - facultative anaerobe, Gram negative rod. - non-motile, grows best at 28 C. - with certain dyes, resembles a safety pin as ends stain darker. - forms biofilms in digestive tract of flea and is transmitted by flea bite.

The spleen, in part, functions to cleanse the lymph. interstitial fluid. cytoplasm. blood.

blood. p.666 - Spleen, left side, behind stomach. Red and white pulp. The red pulp cleans the BLOOD by filtration. Red pulp is also a reserve of monocytes and produces new blood cells in rare situations where the bone marrow is unable to make enough. White pulp - contains B/T lymphocytes - provides an active immune response to microbial invaders.

In order to culture the organism responsible for tularemia, the growth media must contain charcoal. glucose. cysteine. NAD.

cysteine Francisella tularensis -bacteria- non-motile, aerobic Gram negative rod that needs added cysteine to grow in vitro.

Most initial cases of dengue fever are very mild or even asymptomatic. When a second infection with a different serotype of the five known dengue viruses occurs, - the person always develops dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS), which is quickly fatal. - the usual protection from a previous infection is reactivated and quickly eliminates the new virus type from the infected individual. - dengue hemorrhagic fever may develop, due to antibody-dependent enhancement that facilitates viral entry into macrophages. - the two viruses work together to achieve a much more serious infection that is always rapidly fatal.

dengue hemorrhagic fever may develop, due to antibody-dependent enhancement that facilitates viral entry into macrophages.

Which of the following may be transmitted by saliva? infectious mononucleosis rabies plague yellow fever infectious mononucleosis AND rabies

infectious mononucleosis AND rabies Rabies was covered in a different chapter but it is carried by animal in their saliva and we worry about rabies with animal bites. Mono - Kissing disease, saliva

The material released from bacteria that may lead to shock and death in septicemia is exotoxin. protein A. endotoxin. interferon.

endotoxin. = LPS in outer membrane of Gram negative bacteria.

The unique characteristic of Lyme disease is erythema migrans. induration. rash on palms. carbuncle. furuncle.

erythema migrans Bull's eye rash caused by the spreading of LPS and causing an inflammatory response. Borrelia burgdorferi - bacteria- Gram negative, microaerophilic spirochete with many plamsids and a chromosome that is linear and present in multiple copies

Antibody-dependent enhancement (ADE), that explains the pathogenesis of dengue hemorrhagic fever and dengue shock syndrome, can best be described as: - failure of pre-existing anti-dengue antibodies to neutralize a second dengue virus serotype, instead facilitating viral entry into host cells. - the bleeding and shock that occur when the heterophile antibodies made in a nonproductive infection cause blood vessel leakiness. - the lysis of productively infected B cells by antibodies made in response to different dengue viruses during a dengue infection. - the production of large amounts of heterophile antibodies by B cells with a nonproductive dengue infection.

failure of pre-existing anti-dengue antibodies to neutralize a second dengue virus serotype, instead facilitating viral entry into host cells. See you have antibodies from first infection, DHF and DSS occur in person who gets a second infection by a different serotype of the virus - Antibody-dependent enhancement (ADE) means the antibodies from the first infection can't stop the seconds so they create immune complexes that actually facilitate viral entry into cells that have Fc receptors (monocytes/macrophages) where the virus replicates freely so ADE leads to increased numbers of infected cells and a high viral load.

Which species of Plasmodium causes the most serious form of malaria? ovale malariae vivax falciparum

falciparum p.688 - P. falciparum infections are more sever than other types. Can infect ALL RBCs, not just young or old ones, and it encodes a virulence factor called pfEMP1 that causes RBCs to stick to capillary walls, blocking blood flow (if it happens in the brain -> cerebral malaria. Happens in placenta....).

The plague is typically transmitted via the bite of ticks. fleas. lice. mites.

fleas. Y. pestis forms a biofilm in flea guts, they starve and want to bite.

The inflammatory effects of immune complexes lodged in the kidney is called renal phritis. rendema. glomerulonephritis. urethritis.

glomerulonephritis. Correct

The production of heterophile antibody is associated with tularemia. brucellosis. plague. infectious mononucleosis.

infectious mononucleosis. Most B cells get non-productive (latent) infection. EBV activates the B cells, they multiply and make useless antibodies - HETEROPHILE ANTIBODY that can be used to test = Monospot test - causes agglutination when mixed with animal RBCs.

The condition that develops on a previously damaged heart valve is called acute bacterial endocarditis. myocarditis. an aneurysm. infective endocarditis. effective endocarditis.

infective endocarditis Correct

Yops proteins, produced by Yersinia pestis, interfere with phagocytosis. activates plasminogen activator. destroys C3b and C5a. promotes apoptosis.

interfere with phagocytosis. p.670 - Yops (proteins) - interfere with phagocytosis and the immune response. - A variety of Y. pestis outer proteins (Yops) are made and delivered by type III secretion systems to the host cell, they disrupt the host cell cytoskeleton, inhibit phagocytosis, block the production of pro-inflammatory cytokines.

The fluid which bathes and nourishes the tissue cells is the cytoplasm. interstitial fluid. lymph. blood.

interstitial fluid.

Although endotoxemia affects many organs, the organ most seriously and irreversibly affected is the heart. lung. kidney. spleen.

lung. Also seen as, "Although sepsis affects many organs..." endotoxemia = endotoxin in the blood p.668 - still talking about sepsis - Lungs are seriously and irreversibly damaged by tissue-damaging lysosomal enzymes. Lung damage often results in death even if the infection has been cured.

The small bean-shaped bodies into which the lymphatic vessels drain are the lymph nodes. adrenals. subclavian veins. valves.

lymph nodes.

A visible red streak in an infected hand or foot is referred to as septicemia. bacteremia. lymphangitis. edema.

lymphangitis. p.665 - when a hand or a food is infected, a visible red streak may spread up the limb from the infection site toward the nearest lymph node. This is due to inflammation of one or more lympathic vessels, a condition called lymphangitis.

When Gram-negative bacteria are multiplying in the bloodstream, sepsis/septic shock can result. This is due to binding of endotoxin to toll-like receptors (TLRs) on _________ and neutrophils, provoking an uncontrolled release of pro-inflammatory _________ and activating the complement cascade. These events result in a widespread, self-stimulating inflammatory response. macrophages; cells macrophages; cytokines basophils; cells lymphocytes; cytokines

macrophages; cytokines

Which of the following is caused by a protozoan infection? malaria yellow fever tularemia infectious mononucleosis

malaria - protozoa of the genus Plasmodium, transmitted by female mosquitoes of genus Anopheles. - 5 species of Plasmodium involved: P. vivax, P. faciparum, P. malariae, P. ovale and P. knowlesi.

The most common agent(s) causing subacute bacterial endocarditis is/are Streptococcus pyogenes. Pseudomonas aeruginosa. normal skin or mouth flora. Escherichia coli.

normal skin or mouth flora. p.666 - Staphylococcus aureau, Staphylococcus epidermidis, enterococci, variety of Streptococcus species including viridans streptococci from mouth - bacteria Correct

The growth stage of the vector that is mainly responsible for transmitting Lyme disease is the mouse. egg. adult. moulter. nymph stage.

nymph stage Correct

Symptoms of plague appear in two to three months. one to two years. three to six hours. one to six days.

one to six days. p.669 - signs/symptoms depend on how the disease is acquired - through tick bite = bubonic plague - through inhaling respiratory droplets = pneumonic plague - when the causative organisms spreads via bloodstream = septicemic plague

The common name for tularemia is Bang's disease. rabbit fever. Hansen's disease. Chagas' disease.

rabbit fever. Tularemia is a zoonotic disease that occurs among wild animals. Winter months people get it from skinning rabbits. Also called deer fly fever - from bites of infected ticks and deer flies in summer. Can also contract tularemia from eating contaminated meat or from dust arising from mowing or from rodent-infested buildings.

The heart chamber that passes blood to the lungs is the left ventricle. right ventricle. right atrium. left atrium.

right ventricle. Left ventricle send blood to the body Right atrium sends blood to right ventricle Left atrium sends blood to left ventricle

The condition that develops on a previously damaged heart valve is called an aneurysm. acute bacterial endocarditis. myocarditis. subacute bacterial endocarditis.

subacute bacterial endocarditis. Slide 8/p.666 - endocarditis - inflammation inside the heart. Condition develops gradually than it is called SUBACUTE BACTERIAL ENDOCARDITIS. Rapid progression = acute bacterial endocarditis

Acute bacterial endocarditis differs from subacute bacterial endocarditis in the suddenness and severity of onset. population affected. resultant damage. development of exotoxin shock.

suddenness and severity of onset. Subacute is gradual and not as bad. Acute is rapid and bad. - so how sudden and how severe.

Two people are brought to the Emergency Department where you work. The first patient reports fever, abdominal pain, vomiting, and diarrhea. The second patient appears extremely ill. Her family tells you that she also had gastrointestinal signs and symptoms a few days ago. She has now developed severe skin blistering, has a very high fever and is only semi-conscious. When you question the first patient and the family of the second patient, you discover that they know each other and that they have all recently returned from a beach vacation in a major city on the U.S. Gulf Coast. The group tells you that the enjoyed a raw oyster dinner on the last day of their summer vacation. They think that both patients are probably just allergic to seafood, but given the severity of the signs and symptoms of your patients, you suspect that they may have Vibrio vulnificus infection. Lab tests confirm your suspicion. You give the families information on this disease. Patients with V. vulnificus infection are given a combination of synergistic antibiotics. This means that: the action of one antibiotic diminishes the effect of the other(s) in the combination. each antibiotic works independently, but does not inhibit the action of the other antibiotic(s) in the combination. the antibiotics given in combination are always broad spectrum medications. the antibiotics work together to produce a stronger effect than each antibiotic on its own. one antibiotic in the combination is always broad spectrum while the other(s) is/are always narrow spectrum.

the antibiotics work together to produce a stronger effect than each antibiotic on its own. Correct

Development of a dengue vaccine has proved challenging because: - there are five different viral serotypes, so a multivalent vaccine is needed. - dengue viruses, being RNA viruses, have a high mutation rate. - dengue is transmitted by different species of the Aedes mosquito. - dengue viruses are DNA viruses and can integrate into the host genome.

there are five different viral serotypes, so a multivalent vaccine is needed. 4 serotypes, my book says but I still like the answer. Dengue virus is ssRNA of family Flaviviridae.

The development of lymph node enlargement in the region of a skin ulcer after a tick or insect bite or handling of a wild animal suggests brucellosis. endocarditis. septicemia. tularemia.

tularemia. p.676 - Tularemia is a zoonotic disease that occurs among WILD ANIMALS...in the western US infections mostly result from the bites of infected TICKS AND DEER FLIES (insects) Brucellosis is a chronic infection of domestic animals. Zoonosis.

Cytokine(s) released from macrophages in response to exposure to endotoxin is/are tumor necrosis factor. interleukin-1. protein A. alpha-toxin. tumor necrosis factor AND interleukin-1.

tumor necrosis factor AND interleukin-1.

The cytokine released from macrophages that seems to play a major role in endotoxic shock is macrophage factor. tumor necrosis factor. protein A. interferon.

tumor necrosis factor. It's a pro-inflammatory cytokine. The host immune response is activated by TNF-α, as is the subsequent release of cytokines following trauma and infection.

The preferred host of Ixodes scapularis is the moose. wood rat. ground squirrel. white-footed mouse. human.

white-footed mouse.

Which of the following is transmitted by mosquitoes? plague yellow fever malaria tularemia yellow fever AND malaria

yellow fever AND malaria plague is fleas, Y. pestis bacteria tularemia is zoonosis - wild animals, ticks Yellow fever is Aenes mosquitos and a virus malaria is Anopheles mosquitoes and a Plasmodium protozoa

The disease caused by an enveloped single-stranded RNA arbovirus of the flavivirus family is chikungunya. herpes. malaria. yellow fever. brucellosis

yellow fever. AIDS - not arbovirus malaria - protozoa herpes - not arbovirus brucellosis - bacteria - chik is due to the chikungunya virus, enveloped, ssRNA virus of family Togaviridae. Aedes mosquitoes. Yellow fever is caused by an enveloped, ssRNA arbovirus of the family Flaviviridae. - transmitted by bite of infeccted Aedes or Haemagogus mosquitoes, it biological vector. Correct