Rhinovirus Flashcards
T/F. Rhinoviruses are among the most frequent causes of viral infections in humans.
True
Rhinovirus are the major cause of…
Common cold
What is the family of rhinovirus?
Picornaviridae
Mention the three rhinovirus species.
- RV-A
RV-B
RV-C
Receptor used by RV-A and RV-B.
Intercellular adhesion molecule 1 (ICAM-1)
Receptor used only by RV-A.
Low-density lipoprotein (LDL)
Receptor used by RV-C.
Human cadherin-related family member 3 (CDHR3)
T/F. Rhinovirus are enveloped.
False, they are not.
What kind of nucleic acid does rhinovirus has?
Single-straded RNA
Mention the 4 viral proteins of the capsid.
- VP1
- VP2
- VP3
- VP4
Viral protein that contains a canyon that binds to ICAM-1 receptor. It also provides immunogenic surfaces,
VP1
Rhinoviruses are sensitive to commonly used disinfectants like:
- Chlorine
- Iodine
- Hydrogen peroxide
- Ozone
Physical treatments also decrease infectivity; such as:
- Gentle heating
- Desiccation
- Ultraviolet light
What is the global distribution of rhinovirus infections?
Worldwide distribution
In which age group are rhinovirus infections most common?
Infants and young children
T/F. Rhinovirus infections are less frequent in the first 6 months of life.
True
In older adults, which gender has higher infection rates?
Men
During which seasons is rhinovirus more common?
Spring and fall
During peak rhinovirus seasons, what percentage of upper respiratory illnesses are caused by rhinovirus?
Up to 80%
Even during low transmission periods in summer, what percentage of upper respiratory illnesses are caused by rhinoviruses?
50%
What environmental factor has been linked to increased rhinovirus survival and infection rates?
High indoor humidity
Which place increases transmission rates by facilitating close contact among children?
Schools
Where does initial infection occur?
Nasal mucosa or eyes
After inoculation into the nasal cavity, the virus spreads to…
Posterior nasopharynx
T/F. Involvement of the paranasal sinuses may occur.
True
Which cells are primarily affected by rhinovirus infection?
Epithelial ciliated cells
Besides ciliated cells, what other type of cells are involved in rhinovirus infection?
Noncilliated cells
What happens to most rhinovirus-infected cells?
They are likely to shed into nasal secretions
T/F. Rhinoviruses can be found in the lower airway following upper airway infection.
True
These cells are found in both the nasal mucosa and secretions during a rhinovirus infection.
Polymorphonuclear leukocytes
Cytokines that correlate with symptom severity. They decrease as symptoms resolve.
IL-6, IL-8, and IP-10
Thes kinins are found in nasal mucosa during colds. Their concentration correlate with severity and duration of illness.
Bradykinin and lysyl-bradykinin
What regulates the secretory function of nasal seromucous glands?
Parasympathetic innervation
Where does most of the nasal fluid produced during a cold come from?
Nasal seromucous glands and transudation
What are the two main routes of person-to-person transmission for rhinovirus?
- Direct contat
- Aerosol transmission
T/F. Rhinovirus cannot survive on the skin.
False; it can survive for several hours
How does self-inoculation occur in rhinovirus infections?
When contaminated fingers touch the eye or nasal mucosa
What type of aerosols are the main route of rhinovirus aerosol transmission?
Larger particle aerosols from sneezing or coughing
What factors increase the efficiency of rhinovirus transmission?
- Time and closeness of contact
- Children
- Married couples
- Crowded living conditions
- Severity of illness
What is the most frequent illness associated with rhinovirus infection?
Common cold
What is the incubation period for rhinovirus infection?
1-2 days
What are the initial symptoms of a rhinovirus infection?
- Throat discomfort
- Rhinorrhea
- Nasal obstruction
What additional symptoms may occur in rhinovirus infection?
- Hoarseness
- Sneezing
- Headache
- Malaise
- Feverishness
T/F. Fever is present in about one-third of children but is absent in most adults.
True
How long can rhinovirus ilness last?
Between 1 to 33 days. Median of 7 years
What are the main precipitating factors for acute bacterial sinusitis?
- Retrograde propulsion of bacteria into sinuses due to nose blowing
- Occlusion of paranasal ostia and obstruction of ethmoid and infundibulum
What are the key clinical signs of acute bacterial sinusitis?
- Facial swelling, pressure, pain, and tenderness
- Fever
- Persistence of illness beyond the typical 2-week duration of a cold
How do rhinovirus infections contribute to middle ear issues?
Result in eustachian tube dysfunction
What middle ear change is observed in three-fourths of patients with rhinovirus colds?
- Increased middle ear pressures
- Sometimes middle ear effusions
How does rhinovirus impact asthma?
Major cause of wheezing and asthma exacerbations
In which age group are rhinovirus-related asthma episodes particularly significant?
Children older than 2 years
What are the key clinical features of rhinovirus-induced exacerbations of chronic bronchitis?
- Fever
- Increased purulent sputum production
- Deterioration of ventilation
Besides chronic bronchitis, which other respiratory conditions can worsen due to rhinovirus infection?
- Bronchiectasis
- COPD
- Cystic fibrosis
T/F. Rhinovirus can cause pneumonia.
True
What is the preferred method for detecting rhinovirus in current practice?
RT-PCR
What types of samples can be used to detect rhinovirus?
Nasal aspirates, swabs, or washings
This drug binds to the rhinovirus capsid at the hydrophobic pocket formed by VP1, blocking virus attachment, inhibiting ingress, and interfering with the release of viral RNA.
Pleconaril
What is the mechanism of action of Vapendavir (BTA798)?
It binds to VP1 of RV-A and RV-B
This drug is a 3C protease inhibitor that targets the 3C protease of rhinoviruses, which cleaves essential polyproteins for virus replication.
Rupintrivir
Effective in preventing naturally occurring rhinovirus-induced colds (prophylaxis), but ineffective in treatment.
Interferon-α
