1.
What virulence factor do ALL Gram-Negative Bacilli have in common?
Correct Answer
A. Endotoxin
Explanation
All contain endotoxin
Large variety of them also have exotoxins, enzymes capsules, fimbreae
2.
T/F: Gram negative bacilli cause the same types of disease..
Correct Answer
B. False
Explanation
False. They differ in the types of diseases they cause
3.
Which of the following are environmental niches that gram-negative bacilli occupy?
Correct Answer
D. All of the above
Explanation
Gram-negative bacilli are a diverse group of bacteria that can occupy various environmental niches. They are commonly found in the intestines, where they play a role in digestion and nutrient absorption. Additionally, they can colonize the respiratory tract, causing infections such as pneumonia. Gram-negative bacilli are also present in soil and water, where they contribute to the decomposition of organic matter and nutrient cycling. Therefore, the correct answer is "all of the above" as gram-negative bacilli can be found in intestines, respiratory tract, soil, and water.
4.
Gram-negative bacilli can be zoonotic.
Correct Answer
A. True
Explanation
Some are Zoonotic, meaning they cause diseases in animals that can be transmitted to us
5.
Which of the following is NOT a Gram-negative coccobacilli?
Correct Answer
F. Clostridium perfringens
Explanation
Clostridium perfringens is a Gram-positive, spore-forming, rod-shaped bacterium. It is not a Gram-negative coccobacilli, which are typically small, oval-shaped bacteria that stain pink in the Gram stain. The other options listed, Haemophilus influenzae, Bordetella pertussis, Francisella tularemia, Brucella species, and Pasteurella multocida, are all Gram-negative coccobacilli.
6.
All gram negative coccobacilli affect both animals and humans equally.
Correct Answer
B. False
Explanation
They differe in Their ability to infect animals as well as humans
7.
Haemophilus influenzae strains can be divided into two groups based upon
Correct Answer
A. Their ability to produce capsules
Explanation
Encapsulated strains produce the capsule
Unencapsulated strains don’t produce the capsule
8.
Antibodies against the capsule show that there are ____different serotypes for Encapsulated strains of Haemophilus influenzae
Correct Answer
C. 6
Explanation
Antibodies against the capsule show that there are 6 different serotypes (a-f)
9.
Which strain of Haemophilus influenzae causes 90% of noninvasive respiratory tract infections
Correct Answer
B. Nonencapsulated
Explanation
Nonencapsulated strains of Haemophilus influenzae are responsible for causing 90% of noninvasive respiratory tract infections. This means that the majority of respiratory infections caused by Haemophilus influenzae are caused by strains that do not have a protective capsule around them. The capsule helps bacteria evade the immune system, so nonencapsulated strains are more easily recognized and eliminated by the body's defenses.
10.
Which encapsulated H. Influenzae serotype causes 95% of invasive disease (meaning the bacteria enters the bloodstream).
Correct Answer
B. B
Explanation
Serotype B (Hib) causes 95% of invasive disease, meaning the bacteria enters the bloodstream
Almost all Hib cases are in young children
11.
Which of the following virulence factors is not produced by H. influenzae
Correct Answer
D. Exotoxin
Explanation
Fimbriae for attachment to respiratory tract cells
Capsule is produced to prevent phagocytosis
Endotoxin which is part of ALL Gram-negative cells
12.
Which virluence factor produced by H. influenzae helps respiratory tract colonization by blocking cilia clearance and Induces inflammation at site of infection
Correct Answer
C. Endotoxin
Explanation
Endotoxin is a virulence factor produced by H. influenzae that helps respiratory tract colonization by blocking cilia clearance and inducing inflammation at the site of infection. Endotoxin is a component of the bacterial cell wall and is released when the bacteria are damaged or destroyed. It activates the immune system and triggers an inflammatory response, leading to the recruitment of immune cells to the site of infection. This inflammation can impair the function of cilia, which are hair-like structures that help to clear mucus and debris from the respiratory tract, allowing the bacteria to colonize and persist in the respiratory tract.
13.
H. . influenzae causes disease by simply being in the environment and sparking inflammation through endotoxin
Correct Answer
A. True
Explanation
H. influenzae is a bacterium that can cause various diseases, including respiratory tract infections, meningitis, and septicemia. It possesses endotoxins, which are molecules that can trigger inflammation in the body. When H. influenzae is present in the environment and enters the body, it can cause an immune response that leads to inflammation. Therefore, the statement that H. influenzae causes disease by simply being in the environment and sparking inflammation through endotoxin is true.
14.
Which infection is a Systemic infection caused by H. influenza?
Correct Answer
A. Meningitis
Explanation
Meningitis is a systemic infection caused by H. influenza. It is an inflammation of the protective membranes covering the brain and spinal cord. H. influenza is one of the common bacteria that can cause meningitis, especially in young children. Symptoms of meningitis include severe headache, fever, stiff neck, and sensitivity to light. If left untreated, meningitis can be life-threatening. Therefore, it is important to diagnose and treat it promptly.
15.
Which of the following is NOT a virulence factor produced by H. influenza?
Correct Answer
D. Exotoxin
Explanation
Exotoxins are not produced by H. influenza. Exotoxins are toxic substances secreted by bacteria that can cause damage to host cells or tissues. While H. influenza produces other virulence factors such as fimbriae, capsule, and endotoxin, it does not produce exotoxins. Exotoxins are commonly produced by other bacteria such as Clostridium tetani (causing tetanus) or Corynebacterium diphtheriae (causing diphtheria).
16.
Haemophilus influenza is easy to grow
Correct Answer
B. False
Explanation
It is Fastidious… this means it is difficult to grow. We must give it lots of growth factors
17.
Haemophilus influenza quickly invades into cells.
Correct Answer
B. False
Explanation
It is an Extracellular pathogen, does not invade into cells
18.
For which gram-negative bacilli is a protective antibody against the capsule the key?
Correct Answer
A. H. influenzae
Explanation
A protective antibody against the capsule is key for H. influenzae. The capsule of H. influenzae is a major virulence factor that helps the bacteria evade host immune responses. Antibodies against the capsule can neutralize the bacteria and prevent infection.
19.
H. influenzae causes disease by simply being in the environment and sparking inflammation through endotoxin
Correct Answer
A. True
Explanation
H. influenzae causes disease by simply being in the environment and sparking inflammation through endotoxin. This means that the mere presence of H. influenzae can lead to inflammation in the body, which can result in various diseases. Endotoxins are substances released by certain bacteria, including H. influenzae, that can trigger an inflammatory response in the host. Therefore, it is true that H. influenzae can cause disease by being in the environment and sparking inflammation through endotoxin.
20.
Which of the following is NOT a gram-negative bacilli?
Correct Answer
E. Pseudomonas aeruginosa
Explanation
Pseudomonas aeruginosa is a gram-negative bacilli, so it is not the correct answer. Haemophilus influenzae, Bordetella pertussis, Francisella tularemia, and Pasturella multocida are all gram-negative bacilli.
21.
At what age do children begin to make their own antibody to sugars and start to make their own protection?
Correct Answer
C. 2 years
Explanation
At around 2 years of age, children begin to make their own antibodies to sugars and develop their own protection. Before this age, infants rely on antibodies passed on from their mothers through breast milk or during pregnancy. As their immune system matures, children gradually start producing their own antibodies, which help fight against infections and provide immunity. This process is an important milestone in the development of a child's immune system.
22.
What causes meningitis?
Correct Answer
A. Encapsulated strain of H. influenzae
Explanation
Meningitis is caused by the encapsulated strain of H. influenzae. This bacterium has a protective capsule that allows it to evade the immune system and invade the meninges, which are the membranes surrounding the brain and spinal cord. Infection with the encapsulated strain of H. influenzae can lead to inflammation of the meninges, resulting in meningitis.
23.
What are primarily caused by unencapsulated strains of H. influenzae?
Correct Answer
B. Local respiratory tract infections
Explanation
Unencapsulated strains of H. influenzae primarily cause local respiratory tract infections. These infections occur in the respiratory tract, such as the nose and throat, and can lead to symptoms like a sore throat, runny nose, and cough. Meningitis, systemic infections, and whooping cough are caused by other factors or pathogens, not specifically unencapsulated strains of H. influenzae.
24.
Which of the following is NOT one of the best drugs active against almost 100 percent of H. influenzae strains?
Correct Answer
D. Ampicillin
Explanation
Ampicillin is not one of the best drugs active against almost 100 percent of H. influenzae strains. This is because H. influenzae has developed resistance to ampicillin over time, making it less effective against the bacteria. Therefore, while azithromycin, fluoroquinolones, and cephalosporin are all effective drugs against H. influenzae, ampicillin is not.
25.
Which gram-negative bacilli is hard to grow like H. influenzae; however, does not specifically require X and V?
Correct Answer
A. Bordetella pertussis
Explanation
Bordetella pertussis is the correct answer because it is a gram-negative bacilli that is difficult to grow, similar to H. influenzae. However, unlike H. influenzae, it does not specifically require X and V factors for growth.
26.
What is the main difference in virulence factors between bordetella pertussis and H. influenzae?
Correct Answer
C. B. pertussis produces exotoxins
Explanation
Bordetella pertussis produces exotoxins, which are toxic substances secreted by the bacteria that can damage host cells and tissues. These exotoxins play a crucial role in the pathogenesis of pertussis (whooping cough) by causing damage to the respiratory tract and impairing the immune response. On the other hand, the main difference in virulence factors with H. influenzae is that B. pertussis does not have fimbrae or endotoxins. Fimbrae are hair-like structures that allow bacteria to attach to host cells, while endotoxins are lipopolysaccharides found in the outer membrane of Gram-negative bacteria that can cause inflammation and other harmful effects.
27.
Bordatella pertussis does most of its damage in the blood stream
Correct Answer
B. False
Explanation
It is non-invasive and It does all its damage where it lands in the respiratory tract
28.
Which of the following are not an exotoxin produced by B. pertussis?
Correct Answer
C. Pore-forming exotoxin
Explanation
The correct answer is "pore-forming exotoxin." This is because all the other options listed (Pertussis toxin, Adenylate Cyclase Toxin, dermonecrotic Toxin, and tracheal cytotoxin) are exotoxins produced by B. pertussis. Exotoxins are proteins secreted by bacteria that can cause damage to host cells. Pore-forming exotoxins, on the other hand, create pores in the host cell membrane, leading to cell lysis.
29.
W hich exotoxin(s) produced by B. pertussis increases cAMP?
Correct Answer
E. Pertussis and Adenylate Cyclase Toxin
Explanation
The correct answer is pertussis and Adenylate Cyclase Toxin. Both of these exotoxins produced by B. pertussis have the ability to increase cAMP levels.
30.
Which gram-negative bacilli causes whooping cough?
Correct Answer
A. Bordetella pertussis
Explanation
Bordetella pertussis causes whooping cough, also known as pertussis. This gram-negative bacilli is responsible for the contagious respiratory infection that affects the airways and causes severe coughing fits. It is transmitted through respiratory droplets and primarily affects infants and young children. The characteristic "whooping" sound occurs when the infected person tries to inhale after a coughing episode.
31.
With B. pertussis the cells must die and release their toxins to cause the symptoms of the disease
Correct Answer
A. True
Explanation
The statement is true because B. pertussis, the bacterium that causes whooping cough, produces toxins that are released when infected cells die. These toxins are responsible for the symptoms of the disease, such as severe coughing fits, difficulty breathing, and the characteristic "whooping" sound. Therefore, for the symptoms to occur, the cells must die and release the toxins.
32.
W hat is the first stage of whooping cough that occurs just as bacteria just start to die and release toxin?
Correct Answer
A. Catarrhal stage
Explanation
The catarrhal stage is the first stage of whooping cough that occurs just as the bacteria start to die and release toxins. During this stage, symptoms such as a runny nose, sneezing, mild cough, and low-grade fever may appear. It is characterized by inflammation and increased mucus production in the respiratory tract. This stage typically lasts for 1-2 weeks before progressing to the paroxysmal stage, where severe coughing fits occur. After the catarrhal and paroxysmal stages, the convalescent stage follows, where the symptoms gradually decrease and the person starts to recover.
33.
Which stage of the Whooping Cough is the MOST contagious stage?
Correct Answer
A. Catarrhal stage
Explanation
i. This is the MOST contagious stage since many bacteria still alive in respiratory tract and all the coughing and sneezing spread live bacteria easily to other children
34.
What is characteristic of the Paroxysmal stage of whooping cough?
Correct Answer
B. Mucous build-up in Lungs causing air blockage
Explanation
During the paroxysmal stage of whooping cough, one of the characteristic symptoms is mucous build-up in the lungs causing air blockage. This can lead to difficulty in breathing and can be a serious complication of the disease. It is important to recognize this stage and seek medical attention to prevent further complications and to ensure proper treatment.
35.
Secondary pneumonia is biggest threat of Whooping Cough
Correct Answer
A. True
Explanation
The statement is true because secondary pneumonia is indeed the biggest threat of whooping cough. Whooping cough, also known as pertussis, is a highly contagious respiratory infection caused by the bacterium Bordetella pertussis. It primarily affects the respiratory system and can cause severe coughing fits, difficulty breathing, and a characteristic "whooping" sound. While whooping cough itself can be dangerous, secondary pneumonia is a common complication that can occur as a result of the infection. Pneumonia is a serious condition that can lead to further complications and even death, particularly in infants, young children, and individuals with weakened immune systems. Therefore, secondary pneumonia poses a significant threat in cases of whooping cough.
36.
Which of the following is not true about the use of Erythromycin in the treatment of whooping cough caused by Bordatella pertussis?
Correct Answer
A. Significantly eases the symptoms of the disease
Explanation
It has no effect on the disease
37.
Which zoonotic gram-negative bacilli causes undulant fever?
Correct Answer
E. Brucella species
Explanation
these medically important species are named for the livestock they commonly come from
38.
W hich of the following is not used in the prevention of disease caused by Brucella species?
Correct Answer
A. Human vaccine
Explanation
just a note: Tetracycline is the drug of choice when treating the disease
39.
Which zoonotic gram-negative bacilli is found in more than 100 species of animals and insect vectors play an important role?
Correct Answer
B. Francisella tularemia
Explanation
especially rabbits
40.
Which of the following are routes of transmission for Francisella tularemia?
Correct Answer
E. All of the above
Explanation
Francisella tularemia can be transmitted through various routes, including infected tissue, inhalation, ingestion, and insect bites. This means that all of the options listed are correct routes of transmission for this bacterium.
41.
Which Clinical syndrome of Franciscella tularensis is the most common?
Correct Answer
A. Ulceroglandular
Explanation
You see an ulcer at the site of inoculation, is commonly seen in hunters that kill rabbits and skin them. This would be the form seen from insect bite as well
42.
Which Clinical syndrome of Franciscella tularensis has the highest mortality rate?
Correct Answer
C. Pneumonic
Explanation
10% mortality if untreated. It is usually transmitted by primary inhalation, secondary spread from other forms.
43.
Which Clinical syndrome of Franciscella tularensis is caused by the ingestion of contaminated meat or water?
Correct Answer
D. TypHoidal
Explanation
The clinical syndrome of Franciscella tularensis caused by the ingestion of contaminated meat or water is typhoidal. This form of tularemia is characterized by symptoms such as high fever, headache, body aches, and gastrointestinal symptoms. It can also involve the lymph nodes, liver, and spleen. Unlike other forms of tularemia, the typhoidal form does not typically present with ulceration or involvement of the eyes or lungs.
44.
Tetracycline is the antibiotic of choice when treating Franciscella tularensis.
Correct Answer
B. False
Explanation
Gentamicin is (it’s a bactericidal antibiotic)
45.
Which zoonotic gram-negative bacilli can cause septicemia and death in infants that are licked in the face by infected dogs or cats?
Correct Answer
C. Pasturella multocida
Explanation
Cellulitis occurs in people that are bitten by infected animals
46.
Which antibiotic is very effective in treating Pasteurella multocida?
Correct Answer
A. Penicillin
Explanation
Penicillin is very effective, which is rare for gram-negative bacteria
47.
What is the most frequent cause of diarrheal disease?
Correct Answer
A. Enterobacteriaceae
Explanation
4 billion infections per year; 3 million deaths per year; More morbidity than any other bacterial group
48.
Which of the following virulence factors of Enterobacteriaceae is important in the cause of diarrheal disease?
Correct Answer
B. Exotoxins
Explanation
Recall that not all enterics produce exotoxins
49.
What is the most important cause of nosocomial infections?
Correct Answer
A. E. coli
Explanation
The most important cause of nosocomial infections is E. coli. This bacterium is commonly found in the intestines of humans and animals and can cause various infections, especially in healthcare settings. It can be transmitted through contaminated food, water, or contact with infected individuals. E. coli infections can lead to urinary tract infections, pneumonia, bloodstream infections, and surgical site infections. Proper hygiene practices and infection control measures are important in preventing the spread of E. coli in healthcare settings.
50.
Which group of E. coli can cause urinary tract infections, septicemia, and neonatal meningitis?
Correct Answer
A. Extra-intestinal E. coli
Explanation
Extra-intestinal E. coli refers to strains of E. coli that can cause infections outside of the intestines. These infections can include urinary tract infections, septicemia (bloodstream infection), and neonatal meningitis. This group of E. coli is able to cause these infections by invading and colonizing tissues outside of the intestines, leading to various clinical manifestations.