<prompt> An outbreak of diarrhea in a day care center is suspected to be of rotaviral origin. Which test is most appropriate to diagnose this outbreak?CultureEIAElectron microscopyHistologic examination of biopsy  <response>: EIA b is the best test for clinical diagnosis of rotavirus infection. Culture a is now possible but is not routinely done. Electron microscopy c detects rotavirus infection as well as other viruses that cause gastroenteritis, but EM is not routinely available for clinical diagnosis. Histologic examination of biopsy d would show characteristic changes in the small intestinecaused by rotavirus but the changes are similar to those caused by noroviruses; such an invasive test is unnecessary. Serologye is used for epidemiologic purposes only. See the table below for additional information.CHARACTERISTICS OF VIRUSESTHAT CAUSE GASTROENTERITISaFamilyReoviridaeCaliciviridaeAstroviridacAdenoviridaeVirusRotavirusNorovirus, SapovinisMamastrovirusMastadenovirusGenomebdsRNA ssRNA ssRNAdsDNASerotypes5More than 48 or more2 4041EpidemicitySporadic, outbreak, epidemicEpidemic, outbreakSporadic, epidemicSporadicSeasonNov-AprSummer shipsPeak in winterNoneRisk for clinical diseaseInfants 2years; all ages mildAdults; allagesInfant 2 years; all agesInfants; all agesIncubation period1-3 days12-48 hours1-28-10MajorsymptomsFever, vomiting, watery diarrhea, abdominal painVomiting, nausea, watery diarrhea, stomach pain, feverDiarrhea followed by nausea, vomiting, feverFever, watery diarrhea, vomitingDuration of symptoms 3-8 days24-72 hours3-4 days7-14 daysDiagnosisEIAEIAEMEIA 