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