The eastern part of Japan experienced a magnitude 9.0 earthquake followed by a tsunami on the afternoon of March 11, 2011. A significant number of people were displaced from their homes and began living in temporary shelters. These shelters were located in schools, gymnasiums and 1 community centers, some of which were damaged and had inadequate facilities for the number of people they housed. I Subsequently, many shelters were overcrowded and lacked electricity. Much attention has been focused on the incidence of venous thromboembolism (VTE) after disasters since 2004, when the Mid-Niigata Prefecture Earthquake occurred. Some screening activities were undertaken to prevent the progression of VTE. Portable ultrasound machines play a primary role in screening, enabling efficient screening of at-risk populations who may otherwise have unreliable or no access to medical care. The use of ultrasound machines running on battery power allows for screening in areas without electricity. Monitoring the incidence of deep vein thrombosis and other biological data would enable local government authorities and medical staff to effectively manage shelters and temporary housing.