SM 179a - Viral Infections Flashcards
How can adenovirus be prevented?
Oral, live, nonattenuated vaccine for types 4, 7, 21
Separate vaccines given separately
Reserved for military recruits (not available to the public)
What kind of nucleic acid does parainfluenza virus (PIV) have?
(-)ssRNA
Whart are the roles of hemaglutinin and neuraminidase in influenza pathogenesis?
Hemaglutinin and neuraminidase play a major role in inluenza A
-
Hemaglutinin
- Binds sialic acid
- Limits species transfer
-
Neuraminidase
- Role in viral release in propagation
What are the signs and symptoms of 2019-nCoV?
Fever
Cough
Shortness of breath
Myalgias, confusion, headache, sore thorat, rhinorrhea
What is antigenic drift?
What causes it?
A minor change based on mutations in a viral genome
Due to mistakes made by RNA polymerase
Which virus is most likely to cause a “barking cough” in children?
PIV 1 and PIV 2
Barking cough = croup, most often occurs in children
Which viruses are most likley to cause pneumonia in adults?
When I have pneumonia, I-RAPSS myself in blankets
- Influenza
- RSV
- Adenovirus
- PIV
- SARS-CoV
- Sin nombre
Why do so many viruses affect the human respiratory tract?
The respiratory tract is in direct contact with the environment
What animals are associated with MERS-CoV?
Camels
Bats
Humans
How is RSV transmitted?
Respiratory droplets or fomities
What animal is linked to novel-Coronavirus (2019-nCoV)?
Bats
Unclear secondary animal source
What is the most effective prevention for influenza?
What is the efficacy?
Flu vaccine
Efficacy = 20-60%
What kind of nuleic acid does rhinovirus have?
Non-segmented ssRNA
Influenza C causes disease in __________
Influenza C causes disease in children
Adults have protective immunity
What is the “steeple sign?”
Which virus/clinical syndrome is it associated with?
The steeple sign is a radiographic finding associated with croup, usually caused by PIV 1 or PIV 2
What animals were associated with SARS-CoV infection?
Palm civet
What complication of influenza are people younger than 19 receiving long-term aspirin therapy at risk for?
Reye syndrome
Vomiting, confusion, may progress to coma
Which country is the origin of the majority of MERS-CoV cases?
Saudi Arabia
Which viruses are most likely to cause pneumonia in children?
- RSV
- PIV
- Influenza
- Rhinovirus*
- Measles*
- CMV*
* = Not likely to cause pneumonia in immunocompetent adults
Describe the clinical presentation of RSV
- Children and older or immunocompromised adults
- Lower respiratory tract
- Pneumonia or bronchiolitis
- Lower respiratory tract
- Everyone else
- Upper respiratory tract (less severe)
May lead to airway reactivity similar to asthma and decreased lung function
Where does baloxavir act?
Site 1
Inhibits mRNA synthesis - prevents viral protein synthesis
Baloxavir is a cap-dependent endonuclease inhibitor
Where in the human body does RSV replicate?
What areas are typically infected?
Replicates in the nasopharynx
Infects the bronchial epithelium - Infection is restricted to the lungs
Which influenza medication is a neuraminidase inhibitor?
What does it do?
Oseltamivir (Tamiflu)
Prevents the release of new virions from infected cells
Where are outbreaks of adenovirus likely to occur?
Close quarters
Dorm rooms, military barracks, etc
How is adenovirus transmitted
Aerosol droplets
Direct inoculation
Fecal-oral
What is the treatment for RSV?
Supportive
Ribavirin may have some benefit in adults, but do not use in children
Where in the body is rhinovirus likely to cause infection?
Why?
Upper respiratory tract (not lower)
Does not replicate well at high temperatures
What is the treatment for adenovirus?
- Supportive: Most cases are self-limiting
- Antivirals
- If disease is severe: pneumonia, organ-invasive
- Cidofovir (very nephrotoxic)
- Brincidofovir
- If disease is severe: pneumonia, organ-invasive
What kind of nucleic acid doe HCoV have?
Nonsegmented ssRNA
How is influenza diagnosed?
PCR aka molecular assay (preferred)
Rapid antigen detection (not as good)
Run the test of you suspect flu (fever, sore throat, cough, myalgia)
What are the two major drugs used to treat influenza?
What are their mechanisms of action?
-
Oseltamivir (Tamiflu) - This one is better
- Neuraminidase inhibitor
- Prevents the release of new virions from infected cells
-
Baloxavir (Xofluza)
- Cap-dependent endonuclease inhibitor
- Prevents viral mRNA synthesis