One woman died Tuesday and at least 23 others are suspected of suffering so-called economy-class syndrome after evacuating from their homes in the wake of last week's deadly earthquakes in Kumamoto Prefecture, authorities said.

The health consequences of the 2016 Kumamoto Earthquake, which refers to a series of quakes, could be far more severe than initially anticipated, as survivors struggle with an unusually large number of powerful quakes as well as prolonged evacuations.

The flurry of quakes includes a magnitude-6.5 "foreshock" that struck Kumamoto Prefecture on Thursday night and the powerful magnitude-7.3 jolt early Saturday morning.