A) Influenza has glycoprotein spikes of hemagglutinin (H) and neuraminidase (N) .
B) Antigenic drift changes the antigens to reduce immune recognition.
C) Antigenic shift causes changes in the RNA strands.
D) Influenza B viruses undergo both antigenic drift and antigenic shift.
E) H5N1 is the bird flu strain that may cause a pandemic.
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A) Genetic drift creates a need for an annual flu vaccine to keep up with the seasonal genetic changes,and if Genetic shift occurs,an additional vaccine will have to be administered since the shift creates a different strainof virus.
B) Genetic drift creates a need for an annual flu vaccine to keep up with the seasonal genetic changes,and if a Genetic shift occurs,the same vaccine will be effective against both strains.
C) If a novel strain resulting from antigenic shift appears, it is not necessary to get vaccinated because these strains are typically less pathogenic than seasonal strains.
D) The worst influenza pandemics throughout history have occurred as a result of genetic drift rather than genetic shift.
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A) southeast
B) southwest
C) east and Midwest
D) northeast
E) Rocky Mountains
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A) While RSV is most prevalent in infants 6 months of age and younger, the highest mortality rate is in those children with underlying risk factors such as prematurity.
B) Infants aged 6 months and younger are the most susceptible to infection by RSV; however, adults and older children can also become infected with this virus.
C) RSV infects infants aged 6 months and younger; it is unlikely that a 4-year-old would develop a respiratory disease as a result of this virus.
D) Although RSV is most prevalent in infants aged 6 months and younger, usually by age 2 most children have been exposed to this virus.
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A) Streptococcus pyogenes
B) Aspergillus fumigatus
C) Viruses
D) Both Aspergillus fumigatus and viruses are correct.
E) Both Streptococcus pyogenes and viruses are correct.
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A) influenza
B) rhinitis
C) legionella
D) diphtheria
E) SARS
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A) drift; exchange
B) exchange; drift
C) drift; shift
D) shift; drift
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A) Nasal hairs
B) Cilia
C) Mucus
D) Macrophages
E) All of the choices are correct.
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A) No other kinds of drugs and antibiotics can kill the bacteria causing otitis media other than the broad- spectrum class of drugs.
B) The narrow-spectrum drugs are very toxic as opposed to the rather benign broad-spectrum ones.
C) Otitis media is often caused by a variety of bacteria growing together in a biofilm, and the bacteria often exhibit different susceptibilities to drugs.
D) Fungi are the most common cause of otitis media, and the fungi do not respond well to the narrow-spectrum drugs.
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A) auditory canal
B) sinuses
C) nasal cavity
D) eustachian (auditory) tubes
E) subarachnoid space
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A) Few people have ever received pertussis vaccines because there have been links to autism.
B) The strain of Bordetella pertussis that is now the major cause of pertussis is much more virulent than earlier strains.
C) The pertussis vaccine does not seem to protect for a lifetime, so those who received the vaccine as kids may become susceptible in adulthood.
D) People eat so much refined sugars and starches that our immune systems are much weaker, thereby not being able to adequately protect against pertussis bacteria.
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A) All species are human pathogens.
B) Cell walls have waxy lipids.
C) It is an acid-fast bacterium.
D) It exhibits a very slow growth rate.
E) Cells appear as long, slender rods via microscopy.
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A) primary streptococcal
B) primary viral
C) opportunistic streptococcal
D) endogenous
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A) Infants and children are the high-risk groups, and their mortality rate is higher than for other ages.
B) Both bacteria produce potent exotoxins.
C) They induce autoimmune states in the patients.
D) There are no antibiotics useful for diseases caused by these bacteria.
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A) coronavirus
B) adenovirus
C) rhinovirus
D) herpes simplex virus
E) retrovirus
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A) Aspergillus fumigatus
B) Haemophilus influenzae
C) Candida albicans
D) Corynebacterium diphtheriae
E) Streptococcus pneumoniae
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A) produces several virulence factor enzymes and an exotoxin.
B) integrates its genome into host cell DNA.
C) can survive for 8 months in fine aerosol particles.
D) has a capsule.
E) lives in the soil.
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