Rubellainfectionbelongstotheclassicalchildren´sdiseaseswithalife-longimmunity,andthevirusisspreadworldwideendemically.Innon-vaccinatedpopulations,80-90%oftheinfectionsoccurduringthechildhood.Inspiteoftherubellavaccination,introducedin1974,inGermanytherecontinuetoappearconnataldiseases.
ThecausativeagentisageneticallystableRNAvirus,whichbelongstothegenusrubiviruswithinthefamilyoftogaviridae.Humanbeingsaretheonlyknownnaturalhostsfortherubellavirus.Thetransmissionoccursviadropletinfection,withanincubationtimeof14-23days.
Clinicallythediseasemanifestsitselflikealightfluinfection.Thenucalandretroauricallymphnodesareswollen,andamoderateenlargementofthespleenisobserved.Ashortandmediumraiseoftemperatureappearstogetherwitharatherslightsensationofillness.Rubellaisovercomeeasilywithinsignificantandlightsymptomsduringthechildhood,howevermoreattentionisrequiredinthecaseoftheinfectionofnon-immunizedpregnantwomen,becauseofthepossIBLemalformationsofthefoetus,whichcanbegenerated.Astheinfectioncanbetransmittedviatheplacenta,thedevelopingfoetuscansufferseveredamages,thefrequencyandgravityofwhichisdependentonthemomentofinfectionduringpregnancy.Arubellainfectionduringthe1sttill4thmonthcanleadtoaspontaneousabortionorprematurebirth.Sinceaspecificcausaltherapydoesnotexist,thesecondarysignslikefever,arthritisorarthralgiesaretreatedsymptomatically.
Theclinicaldifferentialdiagnosisisproblematic,becausesimilarexanthemsandfeverishillnessesappearalsointhecourseofotherchildren´sdiseaseslikemeasles,scarletandparvovirusitis.
Thefollowinglaboratorymethodsareavailable:hemagglutinationinhibitiontest(HIT),hemolysisin-geltestorELISA.Thedetectionofvirus-specificIgMantibodiesisimportantfortheassessmentoffreshinfections,andtheIgGtestisusedforthedeterminationofimmunity.Inthecaseofsevereconnatalinfections,theisolationoftherubellavirusfrompharyngeallavage,urineandothersecretionscanalsobeperformed.