MT4 - Orthomyxo/influenza Flashcards
Influenzaviruses have segmented genome
T
HPAI and LPAI strains differ in the number of basal amino acids in the HA protein
T
HA protein of influenza viruses is responsible for the attachment to the cell
T
attachment to the host cell sialic acid (SA)
The M2 protein of influenza viruses serves as an ion channel important in the decapsidation
T
Antigenic drift means serials of point mutations in the HA and NA genes
T
» serial point mutations = antigenic drift → seasonal influenzas
The NA protein in the influenza virus is responsible for the release from the infected cells
T
role in release and spread by digesting the cell surface sialic acid receptors
Enzymatic cleavage of the HA protein is needed for the influenza virus penetration into the cell
T
Genetic reassortment of human and animal influenza viruses result in the occurrence of new human influenza strains
T
Bats have an important role in the epidemiology of influenza
F
Antigenic shift is behind the influenza pandemics
T
Influenza viruses are classified into genera by their HA and NA proteins
F- classified into serotypes
Influenza causes persistent infection in donkey
F
long-term persistence is not known/ not significant
The serotype of influenza viruses is determined by their HA and NA proteins
T
The influenza viruses cause respiratory signs in sea mammals
T
- seals, whales
- horse
- swine
- avian
The host range of influenza virus is determined by the NA protein
F
- HA
The bird to human host switch of influenza virus is mediated by swine
T
The main host of influenza is the swine
F
in humans inactivated vaccines are used for the immunisation against influenza
T
- attenuated
- inactivated
Antigenic drift is behind the seasonal influenza epidemics
T
Antigenic shift means the reassortment of the influenzavirus genome segments
T
Influenzaviruses are sensitive to drying out
T
For the in vitro propagation of influenza viruses embryonated eggs is used
T
virus isolation – embryonated eggs, cell cultures
In horse and van influelnza !
The high virulence of some influenza A viruses is the result of mutations in the HA gene
T
» serial point mutations = antigenic drift → seasonal influenzas
Dogs are susceptible to horse origin influenza strains
T