UR viral Flashcards
What is the temperature that upper respiratory viruses replicated?
33-35 C
What is the most common viral infection of the upper respiratory tract?
Rhinovirus
What are the symptoms of the common cold? What are not?
Rhinitis
Pharyngitis
No high fever, respiratory tract involvement
What is the incidence of colds?
2-3/year for adults, 6-8/yr for child
What are the three major complications associated with the common cold?
OM
Sinus infection
Asthma exacerbation
What should always be included in the dx for chronic upper respiratory tract infections?
Allergies
What are the four most common causes of the common cold in order?
- Rhinovirus (most)
- Coronavirus
- Other known
- Unidentified
Rhinoviruses are members of what family? What type of genome? What are the three viral species? Are they enveloped?
Picronavirus
+ssRNA
A, B, C
No envelope
How are rhinoviruses spread?
Respiratory secretions
How much virus is needed for inoculation?
Very small amount
What is the incubation period for rhinoviruses?
1-3 days
True or false: rhinoviruses do not exacerbate asthma or COPD?
False
What is the MOA of rhinovirus?
- attach to cilia
- disrupt epithelial cell layer
- fluid outpouring from the LP
What are the treatments for rhinovirus? When are abx indicated?
Symptom management
Abx only if there is an associated bacterial infx
Why is it hard to get immunity to rhinoviruses?
Over 100 serotypes
Is there any vaccine for rhinoviruses? If so, which serotypes?
No–too many serotypes
What is the genomic make up of corona viruses? Enveloped? Where do they replicate?
+ ssRNA
Enveloped.
Replicate in the epithelial cells of the upper respiratory tract
What is the optimal temp for Non-SARS coronaviruses? SARS one? What is the significance of this?
33-35 C for non
37 for SARS
This explains the differing symptoms
Transmission of the coronavirus through what?
Large droplets
What is the incubation period of coronavirus?
3 days
What is the treatment for infx with coronavirus? Is there a vaccine? If so, which serotypes?
symptomatic
No vaccine
What is the only common cold virus that has a DNA genome? Is it enveloped?
Adenovirus (dsDNA)
Non-enveloped
What is the surrounding halo around adenoviruses?
Toxins
What are the most common adenoviruses that cause respiratory disease?
1, 2, and 5
Individuals can shed adenoviruses for how long?
18 months
Where can adenoviruses survive where other viruses cannot? What is the significance of this?
Lymphoid tissue–allows a longer period to shed
Which of the upper respiratory tract viruses have no seasonal pattern of disease?
Adenovirus
What is the cause of pharyngealconjunctival fever?
Adenovirus
Serotypes 40 and 41 or adenovirus cause what diseases?
GI diseases
Are there vaccines to adenovirus? If so, for which serotypes?
yes, one for serotypes 4 and 7
What is the viral cause of croup, bronchiolitis, and penumonia?
Paravirus
Rhinoviruses infect which cells?
The ciliated mucosal epithelial cells.
Early in an infection with rhinovirus, nasal secretions are primarily due to what? Later?
Initially increased vascular permeability
Later d/t increase in lactoferrin, lysozyme, and IgA
The damage caused by viral infections and predispose patients to bacterial infections how? (2)
Interruption of mucociliary escalator
Weakened immune system
Why is it possible to get reinfected with a coronavirus?
We develop poor immunity to the virus
What is the treatment for infection with adenoviruses?
Symptomatic
Do you developed good immunity to adenoviruses?
Yes, but there are so many serotypes
What is the family of coxsackieviruses? Are they enveloped? What is their genetic material?
Subfamily of picornaviruses
Non-enveloped
+ssRNA
Where can coxsackie viruses survive, where other viruses cannot?
GI tract (can survive low pH)
What is the mode of transmission for coxsackie viruses?
Fecal-oral route
Are there vaccines available for the coxsackie virus? If so, which serotypes?
None
What is the prognosis for infection with coxsackie viruses?
Full recovery in a few weeks
What is the viruses that causes herpangina?
Coxsackie virus
What are the symptoms of herpangina? (2)
Abrupt fever
Small vesicles on soft palate.
What are the possible complications associated with herpangina?
Meningitis or encephalitis
What is the virus that causes hand-foot-and mouth disease? Symptoms? (2)
Coxsackie
Fever
Vesicular lesions on the soles of the hands, feet, and in oral areas.
What are all the viruses that cause the common cold? (6)
- Rhinovirus
- Non-SARS corona
- Adenovirus
- Coxsackie
- Parainflu (B &C)
- Respiratory syncytial virus
- Flu
What is the only common cold virus that is not caused by droplets?
Coxsackie
What is the only dsDNA virus that causes the common cold?
Adenovirus
What are the symptoms of croup? (3)
Fever, seal’s bark, inspiratory stridor
What is the prodrome for croup?
Rhinorrhea, mild cough, pharyngitis
What are the complications for croup?
Hypoxia
Why is croup more worrisome in children?
Smaller airway