Viral infections of respiratory system Flashcards
what diseases can respiratory syncytial virus cause?
- Pneumonia
- Croup (inflammation of larynx and trachea)
- Bronchiolitis
- transmission is usually through fomites (direct and indirect contact)
- no treatment or vaccine
- What type of virus is RSV - describe as best as you can, in terms of sense, DNA/RNA, Family name
- Paramyxovirus (family)
- Enveloped RNA Negative sense
Influenza symptoms include:
- high fever
- malaise
- myalgia (pain in muscle or group of muscles)
- headache
where does influenza only affect?
- respiratory epithelium
Primary Viral Pneumonia vs Seecondary Bacterial pnem.
- -> Primary is viral
- fatal
- -> Secondary is bacterial
- less lethal
3 types of influenza:
- A
- B
- C
which type causes the deadliest epidemics and pandemic?
—–> A
- B is milder
- C mild URTI only
which family does the Influenza virus belong to?
Orthomyxovirus
What is the Haemaggluttin Protein (HA) ?
attachment protein found on surface of influenza virus
- 3 types of HA in Influenza type A
- only 1 type in Influenz. B
Haemagglutin is also a fusion protein as well as an attachment protein….. what is meant by fusion protein
- fuses cell membranes together at low pH in endosome
what does haemagglutin (HA) bind to?
binds to Sialic acid ( neuramaic acid)
what are the 3 types of HA found in Influenza type A ?
- H1 , H2, H3
-ONLY HA found in type B
What is Neuraminidase (NA) and where is it found?
it is a cell surface glycoprotein
- it is an enzyme that removes the terminal sialic acid
- important for release of newly formed virions from surface
which types of NA are present in influenza type A and B?
- Type A : N1, N2
- Type 2 : NA only
what does Amantadine do?
- it inhibits the viral uncoating of nucleic acid
- only works on Influenza Type A bcas B doesnt have the M 2+ ion channels
How does the nucleic acid usually uncoat?
- M2 ion channels
- causes protons to enter virus
- therefore nucleic acid can uncoat
