Respiratory tract infections 4 Flashcards
which surface glycoprotein is the major one associated with antigenic drift?
hemagluttinin
when you grow a pathogen on a blood agar, the colonies change in color to pink. What pathogen could this be?
moraxella catarrhalis
tamiflu is used to treat the flu by blocking _____
neuraminidase
which influenza strain can undergo reassortment (antigenic shift) ?
only influenza A because there are no animal hosts for influenza B and C
the most common cause of otitis media is _______
moraxella catarrhalis: gram negative diplococci, oxidase positive, strictly aerobic and non motile
influenza type _____ has more ability to result in fatal illnesses and have fatal complications
influenza type B
pandemics result from antigenic drift/shift
SHIFT; it is the sudden reassortment of the eight genetic subunits of the influenza virus
with the flu, what are the additional symptoms you would expect to see in kids?
- higher fever
- GI symptoms
- otits media
- muscle pain
- croup (involvement of larynx and trachea)
- febrile convulsions
local symptoms in the flu results from ________
epithelial damage, including ciliated mucous secreting cells
_______ and _______ target the M2 ion channel protein in influenza type A virus
amantadine and rimantadine
drugs that target the M2 ion channel protein will inhibit _______ in ONLY ______
the uncoating of the virus in only influenza A virus because that is the only one that has the M2 protein
what is the “hockey puck sign” and what pathogen is it seen with?
- when you take a probe to move the colonies, most of the colonies will disintegrate but with hockey puck sign, the entire colony moves l
- seen with MORAXELLA CATARRHALIS
how do you differentiate between the two gram negative diplococci: _____ and _____
moraxella catarrhalis and Neisseria
moraxella is DNase positive and Nitrate reduction positive
the major function of neuraminidase in _____ is ______
influenza; aid in the exist of the virus from the host cell
acute exacerbation of COPD is associated with infection of what pathogen?
moraxella catarrhalis
M2 ion channel is only present in _____ subtype of influenza virus
influenza virus A
influenza C has ________ DNA/RNA segments
7 segments of RNA
hemagglutinin helps the influenza virus attach to the host cell by binding to ________ receptors
sialyloligosaccharide receptors
segmented _____ genome of influenza promotes genetic diversity by _____ and ______
RNA;
mutations and reassortment
Zanamivir and Ostelamivir MOA and use
inhibits neuraminidase and so blocks the release of the virus from the host cell
works on influenza type A and B (not C)
systemic symptoms in the flu is caused by _________
interferon and cytokine response to the virus
influenza type_____ is a disease birds
type A
colonization by _________ depends on age and comorbidities such as COPD
moraxella catarrhalis
describe the biology of moraxella catarrhalis:
- gram +/-
- oxidase +/-
- motile/non motile
gram negative diplococcus
strictly aerobic
oxidase positive
NON motile
influenza A viruses are further classified by subtype on the basis of ____________
surface glycoproteins:
Hemagglutinin (H/HA) and Neuraminidase (N/NA)
migration from the nasopharynx to the Eustachian tube in otitis media is precipitated by ______
viral URI
influenza virus replicates in the ______
nucleus
gram negative diplococci that is nitrate reduction negative; what could it be?
- Neisseria;
moraxella is nitrate reduction positive and DNase positive
the first step in the pathogenesis of otits media caused by moraxella catarhallis is _____
colonization of nasopharynx and then spreads to the middle ear via the Eustachian tube
moraxella catarrhalis targets ________ cells in the respiratory epithelium
type II alveolar cells which then inactivates complement and forms biofilm
what are some things that moraxella catarrhalis can do?
- most common cause of otitis media
- exacerbates COPD
influenza is divided into A, B and C types based on ________
nuclear proteins and matrix proteins
does influenza type B have an animal host?
no. it is an human infection;
__________ (subtype of ______) has 8 RNA segments
influenza A and B
which influenza strain can undergo mutational (antigen ic drift) ?
BOTH influenza A and B
how can you differentiate symptoms of the common cold from those of the flu?
- VERY rapid onset of symptoms in flu
- systemic features are very prominent in the flu (severe headache and malaise)
- fever is present in both adults and kids for the flu (common cold usually only see fever in kids)
- GI symptoms more prominent in flu
which influenza strain is capable of causing epidemics?
A and B
antigenic _____ occurs usually as a the result of co-infection of two difference influenza A strains in a single pig
SHIFT
what pathogens are able to hemagglutinate?
- Adenovirus (fiber protein)
- coronavirus (spike protein)
- influenza virus (H surface glycoprotein)
what are two major gram negative diplococci?
- Neisseria
- Moraxella catarrhalis
what are the 3 ways that moraxella catarrhalis can exacerbate COPD?
- altered mucociliary function
- airway colonization and infection
- triggered by acquisition of new strains
which influenza strain is capable of causing pandemics?
A
what is the MOA of amantadine and rimantadine?
inhibits the M2 protein which inhibits the uncoating of influenza type A
describe the biology of the influenza virus
spherical, enveloped, segmented negative sense ssRNA
which surface glycoprotein is more commonly associated with antigenic shift?
neuraminidase
the acidification and envelope fusion of the receptor mediated endocytose virus is caused by ________
the M2 ion channels which bring in H+ ions into the host cell
what are some symptoms that are common with the common cold but rare with the flu?
- nasal discharge/ runny nose
- sore throat
