POC: Infectious Diseases Flashcards
(32 cards)
What components of HIV virus can be measured for detection
Antigen : using Abs specific for target
HIV RNA—- normally via like PCR or some type of DNA amplification
Body’s immune response to virus (our own production of Ab)
What do rapid HIV tests measure
Ab produced against HIV 1/2 proteins
—- detect whether our body has mad Ab to HIV (would indicate infection )
T or F: 1/4 of people are infected with HIV and are unaware
T
T or F: POC rapid tests are as accurate as lab ELISA tests
T
T or F: HIV tests use lateral flow technique like pregnancy tests
T
How do POC HIV tests work
flow through tests
- Ag of HIV on the test film itself
- load sample ( if infected—- will have Ab to HIV protein that will bind to Ag on film)
- as sample loaded + passes through film; binds to Ag
- add detection solution (Ab + detector) that can bind to Ab for HIV ( 2nd Ab)
——-if Ab from our sample present: bind to Ag ; 2nd Ab with detector will then bind to Ab if present (no Ab —- detector just pass through)
What types of samples can be used for HIV testing
blood, serum, plasma, urine or saliva
-varies based on test type
** can get results in mins
T or F: INSTI HIV test is super sensitivity but low specificity
F
high both
—- low false + rate + high LR+ : if +: likely have disease
—- low false - too
What is the main problem with POC HIV tests
expensive
What is pharyngitis
inflammation of throat + surrounding tissues
—- 90% viral; can be B though
What factors increase chance your pharyngitis is B
</=14
season: late fall, winter or early spring
- acute pharyngitis
- tender/enlarged lymph nodes
-fever
- absence of symptoms of URI (cough)
What are some tests pharmacies can use to detect B pharyngitis
Rapids for GAS
immunoassays for GAS Ag
General steps to strep rapids
has 2 different buffers: add 4 drops of each to tube
- get sample + add to solution + spin 5X times
- leave in for 1 min
- dip test strip in + wait 10 seconds
Is a rapid strep test good for ruling out strep
NO — low sensitivity (if -: could still have Bacterial cause)
high specificity though: if + —- you + (good at ruling in)
What are the different things Covid tests can measure
vRNAL uses in PCR (gold standard); good for early detection even if no symptoms (can be + for longer though —- even if not infectious anymore — false +_
vAg: rapid antigen tests
Ab against virus: serological tests
- can tell us who was infected in the past (can’t tell if infected now or past); good to see prevalence of infection in pop
How do rapid covid tests work
lateral flow tests
- include Ab for nucleocapsid protein found on outside of virus
— can detect within 0-7 days of symptoms; more likely to give false - especially during first couple days of infection
— if -: retest in couple days ( 48 hours)
T or F: there are rapid tests that measur spike protein levels (COVID)
F- don’t measure because spike proteins are include in vaccines + a lot of variation bw different strains of virus
Are rapid tests still available for free ON?
yes - for eligible pops (though who can get antivirals)
T or F: pharmacies can do sample collection for covid PCR or in store rapid molecular testing
T- still in scope
—- also allowed to order PCR tests
T or F: pharm, interns, techs are allowed to collect sample for PCR (oral, throat, or nasal)
F- only pharmacists are allowed
- can’t do nasopharyngeal collection
—-if sample for rapid test: all can do
T or F: for rapid covid tests, false - are super common
T- one single - result doesn’t rule out infection (may take a couple days for enough virus to build up in body to a level that can be detected)
false - normally due to testing too early or not good sample collection
What can cause false + (covid)
false + are rare (high specificity)
— could be caused by eating acidic food before, not using enough buffer or leaving test sitting around for too long
T or F: we can improve sensitivity of covid test by swabbing cheek, throat/back of tongue + both nostrils
T
