Influenza - 139 Flashcards
Name some of the ‘geriatric giants’
Confusion, falls, poor mobility, collapse, incontinence, not coping
What is delirium?
Disturbance of consciousness with reduced ability to focus, sustain, or shift attention. Usually acute, not due to pre-existing dementia
How would you manage delirium?
Well lit room, same nursing staff if possible, repeated orientation, glasses/hearing aid if worn, identify and treat cause
Why is increased drug use in the elderly a problem?
They have altered drug responses
How are drug responses altered in the elderly?
- First pass metabolism decreases with age -> some drugs (e.g. B-blockers and Ca channel blockers) undergo extensive first pass metabolism and will not be properly metabolism in the elderly.
- achlorhydria increases with age, which affects drug absorption
- Elderly have an increased proportion of body fat and decreased proportion of muscle mass -> leads to increased distribution of lipophilic drugs and decreased distribution of hydrophilic drugs
- Renal function declines with age
What is achlorhydria?
Little or no hydrochloric acid in GI secretions
What is the average incubation period for influenza?
2-3 days
Fever, chills, headache, aching muscles, weakness and anorexia are symptoms of what?
Influenza
How is influenza transmitted?
Airborne and through indirect surface contamination
What are neuraminidase and hemagglutinase molecules? What are their specific roles?
Proteins on the surface of viruses. H mediates virion binding to target cells, N is involved in the release of progeny virions from host cells
Mistakes made during virus replication resulting in the production of a virus with different antigenic proteins describes what phenomenon?
Antigenic drift
What is antigenic drift? Why does it take place?
Mistakes made during virus replication resulting in the production of a virus with different antigenic proteins
RNA viruses do not have proof reading mechanisms
What is antigenic shift?
The formation of a new flu virus due to reassortment of genetic material - can be from 2 different flu types, e.g. human and avian
Influenza pandemics occurs because of what phenomenon?
Antigenic shift
Why are flu pandemics dangerous?
The population has no pre-existing immunity. Human-human transmission is possible
In what age group is H1N1 most common?
5-14 years
What 2 drugs can be given to treat influenza?
Oseltamivir (tamiflu) - within 48 hours
Zanamivir - within 36 hours
When is antiviral treatment indicated?
When flu is circulating, an ‘at risk’ person, if treatment can be started within start time (48 hours latest)
In what exception would antivirals be started after 48 hours?
Life-threatening condition
Who is the influenza vaccine offered to annually?
- 65 + years
- between 6 months - 64 years in ‘at risk’ group
- all those over 2 years and under 18 years
What kind of virus is herpesvirus?
DNA, ds, enveloped
What kind of virus is poliovirus?
RNA virus, +ve stranded, icosahedral
Name 2 viruses that are from the family Paramyxoviridae
Mumps and measles
What kind of viruses are measles and mumps?
RNA, SS
What is the most common route of viral penetration?
Receptor-mediated
What kind of surfaces can undergo surface fusion as their route of penetration?
Enveloped
What infections could aciclovir be used to treat?
HSV and VZV
What infections could ganciclovir be used to treat? What are side effects of this?
CMV.
Can cause neutropenia, or anaemia
Which route is the most common route of viral infection?
Respiratory route
Which cells are thought to be used by many pathogens for entry? Give an example of a virus
M cells of the gut. Reovirus
