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Changestothebacteriathatliveinsideallofusareresponsibleforincreasingthenumberofpeoplewithallergies,suggestsnewresearch.InthisepisodeofHorizon,theshowinvestigatesthisclaimbyconductingauniqueexperimentwithtwoallergicfamiliesinordertofindoutjustwhatitisinthemodernworldthatistoblame.Witharaftofminicameras,GPSunitsan...收起
