The severe conditions facing evacuees from the series of quakes in Kumamoto Prefecture are starting to take a heavy toll on the health of the residents who were forced to flee their homes. On Wednesday the prefecture reported that 11 people have died of health problems related to evacuation from the quakes. As protracted evacuation appears inevitable given the extensive damage caused by the temblors and the continuing aftershocks, the authorities should take steps to move the evacuees out of the disaster areas to ensure their safety and health.

The reported death of a 51-year-old woman in the city of Kumamoto due to "economy-class syndrome" — or deep-vein thrombosis — points to the potential health risks for the tens of thousands of people taking shelter outside their homes since their residences were either destroyed or damaged or they fear further damage from the aftershocks. The woman was among an unknown number of evacuees who are sleeping in their cars to avoid the overcrowded public shelters.

Nearly a week after the first of the chain of powerful quakes hit Kumamoto on April 14, over 100,000 people in that prefecture alone remain evacuated, though the number has fallen from the peak of roughly 180,000 after the biggest temblor hit early Saturday. The figure may not go down significantly anytime soon, since aftershocks continue with an unusual intensity and frequency. The total number of quakes to hit the area has topped 700 and rising, and the Meteorological Agency says it's hard to forecast the trend of seismic activity in the days ahead.