Aron Megrelishvili was born in 1900 to a family of Georgian Jews. He was drafted into the Red Army by the Kutaisi conscription office on June 23, 1941 the second day of Operation Barbarossa, as a doctor. In the fall of 1942, when the Germans occupied most of the North Caucasus, he was appointed deputy head of a department in the 11th (North-Caucasian) Administration of Evacuation Centers. In this capacity, Captain of Medical Services Megrelishvili had to carry out a selection among the wounded and sick who were arriving at his evacuation point. He had to separate the more seriously wounded or sick, who were to be transported to a homefront hospital by so-called sanletuchka ("medical flying trains") or by "slow trains," from those who could be or had to be treated on the spot. In many cases, he accompanied such trains, deciding which of the patients had to be most urgently transferred to a local military hospital. During the Red Army offensive in the North Caucasus in February and March 1943 (following the Stalingrad operation), he was responsible for the evacuation of 41,300 wounded and sick soldiers. During his service in Krasnodar in April-May of that year, he selected 27,500 wounded and sick for treatment in the city, while transporting 39,800 to the deeper homefront Megrelishvili's service was difficult physically, as well as emotionally. During the loading of wounded and sick onto the "flying train," he helped carry the stretchers with his own hands, sometimes under enemy bombing and shelling. For example, on May 30, 1943, the railroad station at Krasnodar, where he was preparing a transport of wounded to the rear, suffered from a heavy bombing raid. Captain Megrelishvili and his assistants then had to render first aid to an additional 150 wounded. Accompanying the wounded and sick in the sanletuchka required Megrelishvili to remain awake day and night.
In June 1943, Aron Megrelishvili was recommended for the Order of the Red Star but instead, was given the less prestigious medal For Courage. In 1944 he was awarded the medal For the Defense of the Caucasus.