Product Manual
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SofiaInfluenzaA+BFIA
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Monoclonal antibodies may fail to detect, or detect with less sensitivity, influenza A viruses that have
undergoneminoraminoacidchangesinthetargetepitoperegion.
IfdifferentiationofspecificinfluenzaAsubtypesandstrainsisneeded,additionaltesting,inconsultation
withstateorlocalpublichealthdepartments,isr
equired.
Samplescontaminatedwithwholeblood>4%v/vormucin>0.5%v/vmayinterfereintheinterpretationof
thetest.Visuallybloodyoroverlyviscoussamplesshouldnotbeused.
Theperformance of this test has not been evaluated for use in patients without signs and symptomsof
respiratoryinfection.
EXPECTEDVALUES
Seasonal outbreaks of influenza occur worldwide in both the northern and southern hemispheres causing
widespreadillnesseach winter. The average attackrateof influenza is26‐33cases per 100peopleper year.
Theriskofhospitalizationisroughly1/300ofthoseinfectedamongtheveryyoungandelderly.Overaperiod
of30years,between1976and2006,estimatesofflu‐associatedde
athsintheUnitedStatesrangedfromalow
ofabout3,000toahighofabout49,000people.
2
Ninetypercent(90%)ofdeathsoccurinthose65yearsof
ageandolder.
4
Influenzapandemicsoccurredin1918 ,1957,1968and2009.The1918pandemicresultedinan
estimated 40‐50 million deaths worldwide. The prevalence observed with the reference test (viral culture)
duringthe2011clinicalstudyforSofiaInfluenzaA+BFIAwas15%forinfluenzaAand13%forinfluenzaB.
PERFORMANCECHARACTERISTICS
SofiaInfluenzaA+BFIAPerformancevs.CellCulture
TheperformanceoftheSofiaInfluenzaA+BFIAwascomparedtoviralcellculturemethodsfollowedbyDirect
FluorescentAssay(DFA)inamulti‐centerclinicalfieldstudyduringFebruarythroughMarch2011intheUnited
States. This s tudy was conducted by health care personnel at seventeen (17) distinct professional and CLIA
waivedsites(combin
ed)invariousgeographicalregionswithintheUnitedStates.Inthismulti‐center,point‐of‐
care(POC)fieldtrial,two(2)nasalortwo(2)nasopharyngealswabsornasopharyngealaspirate/washsamples
werecollectedfromeachoftwothousandsixty ‐six(2066)patients.Sixhundredseventy‐one(671)provideda
pairofnasalswabsamples,sevenhun
dredthirty‐four(734) providedapairofnasopharyngealswabsamples,
and six hundred sixty‐one (661) proved a nasopharyngeal aspirate/wash sample. All clinical samples were
collectedfromsymptomaticpatie nts:74%were<6yearsofage,22%6‐21yearsofage,4%22‐59yearsofage,
and1%≥60ye
arsofage.Fifty‐threepercent(53%)weremaleandforty‐sevenpercent(47%)werefemale.
Atotalof2047prospectiveclinicalsamplesweretestedusingtheSofiaInfluenzaA+BFIAandgavevalidresults
duringthisclinicalstudy.TheseresultswereincludedinTables2 ‐6.Theinvalidratewas0.9
%(19/2066)with
95%CI:0.6%to1.4%. The invalidresults wereexcludedfromTables2‐6becausenewpatientsamples were
notcollectedforre‐testing.
On‐site testing of one nasal swab or nasopharyngeal swab, or a portion of nasopharyngeal aspirate/wash
sample, was performed by medi
cal personnel in the physician’s office or hospital facility with the Sofia
Influenza A+B FIA. All samples were freshly collected and tested. The remaining sample was placed in viral
transport media for culturing. The paired swab samples or paired aspirate/wash samples were randomized
with respect to the order of testing in the Sofia Influen
za A+B FIA versus culture. Viral cell culture was
performed either at a local clinical laboratory at the test site, or the samples were transported cold on ice
packs,notfrozen,overnighttoacentrallaboratoryforculturewithin48hours.ResultsarepresentedinTab
les
2‐6.