InEurope,FSME(Tick-borneEncephalitisreferredtoasTBE)andLymeDisease(Borreliosis)arethemostfrequenttick-borneinfections.BorreliosisisverywidespreadbutTBEisconfinedtospecialendemicregions(inSouthernGermany,Thuringia,Austria,Switzerland,Hungary,Sweden,Czech,SlovakRepublics,Croatia,SloveniaaswellassomeregionsofformerSovietUnion,etc.).
Bothinfectionsaresimilarintheirdevelopment,consistingoftwoormorephases.TheviraemicphaseofTBEhasanincubationperiodof3-14dayswithinfluenza-likesymptomsinthefirstphase(1-8days).Afteranon-febrileintervalofaboutoneweektheinfectionmayenterintoasecondphase,characterizedbyneurologicalsymptomsofvaryingintensity.Thisstagemaylastformanyweeks.
Atthebeginningofthesecondsicknessphase,usuallyanti-TBE-IgMantibodiesaredetectable.Antibodylevelsreachtheirpeakafter2-6weeks.Itcantake10monthsforantibodiestofallbelowthelevelofdetection.Anti-TBE-IgGantibodiesaredetectablesimultaneouslyorafewdaysaftertheappearanceofIgM-antibodies.Infectionmeansimmunitywhichmostlylastsalifetime.Vaccinationwillalsopreventthedisease.RegularSEROlogicalchecksestablishwhetherboostersarerequired("vaccinationmanagement").
TBE-specificantibodiesinCerebrospinalFluid(CSF)maybecausedbyadysfunctionofthehemato-encephalicbarrierbeforeorduringanimmuneresponsetoTBEantigensormaybetheresultofalocalimmuneresponse.TheantibodylevelfluctuationsintheCSFmaydifferfromthoseprevalentinserum/plasma.
WithTBEIgMandTBEIgGitispossIBLetodifferentiatebetweenspecificTBEantibodiesoftheIgGandtheIgMclasses.RheumaticfactorsandspecificIgGdonotinterferewithIgMdeterminationduetotheadditionoftheRF/IgG-Absorbent.ThecombinationofbothtestsystemsallowsthedeterminationofthehumoralimmunestatusfollowingTBE-vaccinationorinfection(IgG),earlydiagnosisofprimaryinfectionwithTBE(IgM)andmonitoringofchangesofantibodylevels(IgM/IgG)inhumanserum,plasmaandcerebrospinalfluid.