Respiratory Viruses Flashcards
Transmission of respiratory viruses?
Virus particles.
Sneezing/Coughing.
Release of salivary droplets.
Inhalation of contaminated air.
Viruses that cause the common cold?
Rhinoviruses >50%
Coronaviruses 10-30%
Symptoms of a common cold?
Sneezing, rinorrhoea, congestion, sore throat, malaise, cough.
Characteristics of Rhinovirus?
Picornaviridae! (+)ssRNA, naked icos NC, Genus: Enterovirus, Species: human rhinovirus A,B,C
Transmission of Rhinovirus?
Respiratory droplets, in air or deposited on fingers, delivered to nose, eyes.
Treatment and prevention of rhinovirus?
Treatment: Supportive, Pleoconaril to asthmatics.
Prevention: Hand antisepsis
Characteristics of Coronavirus?
Coronaviridae, Alphacoronavirus. (+)ssRNA, helical NC, buds from ER.
Characteristics of coronavirus infection?
Occurs spring, early winter, cause respiratory and enteric disease. SARS
What is Paramyxovirus?
Measles virus! (+)ssRNA, envelope - F protein, H protein.
Measles infection involves:
Prodrome of Fever, conjunctivitis, coryza, cough -> rash of flat macules, descending from head to limbs.
Vaccine for measles?
Live attennuated!! widely administered.
Orthomyxoviridae?
Influenza A, (-)ssRNA, 8 segments, helical NC, enveloped, contains RNAdepRNApol.
Characteristics of influenza infection?
incubation: 1-3 days, high fever, cough, chills, sweating, sore throat, severe headache, muscle and joint pains, weakness, can caause pneumonia.
Differences between influenza types A B and C?
A causes pandemics (severe), B is milder than A, and C has only minor symptoms.
Explain antigenic drift
One subtype can have spontaneous mutations which cause it to alter proteins, leading to immune evasion and possibility of re-infecting the original host.
