Week 139 - Influenza Flashcards
What happens to arteries and vein as you age?
Stiffen
What genetic material are Icosahedral viruses likely to have?
DNA & RNA
What genetic material are Helical viruses likely to have?
RNA only (e.g. rabies, measles)
What genetic material are “Complex” viruses likely to have?
RNA mostly (e.g. smallpox, influenza)
Given an example of an Orthomyxoviridae virus
Influenza
Given an example of a Paramyxoviridae virus
RSV, Parainfluenza, Measles, Mumps
Given an example of a Picornaviridae virus
Polio, Rhinovirus
What viruses can infect by surface fusion?
Enveloped only (ph dependent process)
What can aciclovir be used to treat?
Similar to Guanosine
HSV and VZV only (due to viral thymine kinase)
What can ganciclovir be used for?
CMV (retinitis, pneumonia)
What are the side effects of ganciclovir?
Neutropenia, anaemia, thrombocytopenia
What agents can be used for treatment of influenza?
Oseltamivir (Tamiflu) - within 48hrs
Zanamivir (Relenza) - within 36hrs
Neuraminidase inhibitors
What is a capsid?
Protein coat covering the nucleoprotein core or nucleic acid
What is a capsomere?
Protein clusters making up discrete subunits of a viral protein shell
What are the common causes of delirium?
UTI
Drugs
General anasthetics
What factors change with age that affect absorption of drugs?
↑Achlorhydria (ketoconazole, tetracyclins)
↓First Pass metabolism (β-blockers, Ca channel blockers)
What factors change with age that affect distribution of drugs?
↑Body Fat (↑distribution of lipophilic drugs, ↓hydrophilic drugs)
What is volume of distribution and what do the values mean?
↑Volume of distribution = drugs stays in blood
↓Volume of distribution = drugs goes to tissues
What happens to renal drug metabolism with increasing age?
↓Renal function
Elderly may have “normal” creatinine with poor renal function (due to ↓muscle)
What is Digoxin toxicity characterised by?
Dysrhythmias Nausea and Vomiting Xanthopsia (things look yellow) Exacerbated by hypokalaemia T wave inversion
What is an enterovirus?
A genus of Picornaviridae that preferentially replicate in the mammalian intestinal tract
What is a Herpetic whitlow?
A herpes viral infection that results in a painful blistery eruption on one of the digits
What is antigenic drift?
RNA-dependent RNA polymerase - “no proof reading”
Causing “mistakes”
Immunity to previous influenza provides SOME protection
What is antigenic shift?
Infection of same cell by two different Flu types, often from different species
Reassortment
When is Oseltamivir & Zanamivir recommended?
1) Virus is circulating
2) Person is in “at-risk” group
3) Presentation with illness within 48hrs
How does NICE define a person “at-risk” of Influenza Infection?
Chronic Respiratory Disease Chronic Heart Disease Chronic Renal Disease Chronic Liver Disease Chronic Neurological Conditions Diabetes Mellitus Immunosuppressed >65yrs
Who is Influenza vaccine offered to?
All those >65yrs
All those 6months-64yrs in “clinical risk group”
All those 2-18yrs
What is Type I or α error?
False Positive Result
What is Type II or β error?
False Negative Result
What are the types of RANDOM ERRORS?
Type I and Type II
What are the sources of error in clinical trials?
Bias
Random Error
Confounding
What is Bias and Confounding controlled by in a clinical trial?
Randomisation (for both)
And blinding for Bias
How is Random Error controlled in a clinical trial?
Sample size and Significance level
How can confounding be dealt with?
1) In the design of the study (matching, restriction)
2) In the analysis (stratified analysis)
What is Residual Confounding?
Occurs when all known confounders have been accounted for, but there are other unknown confounders
What is the difference between cumulative incidence and incidence density?
Both incidences
But Cum. Inc. deals with the “number” of people
Whereas Incidence Density accounts for the number of “person-years”
How is an Odd’s ratio calculated?
Odds of getting something in a population
odds diseased/odds healthy = Odds ratio
or ad/bc= odds ratio
How is a Relative Risk calculated?
RR= p.exposed/p.unexposed
Why is Direct Standardisation method better than SMR?
SMR - quick, but does not account for stratification of data
D.S. - BUT need more accurate data
