Kensuke Mitsuda was so zealous about eliminating leprosy that he admitted more patients than the sanatorium could reasonably accommodate.

This led to an atmosphere of unrest, and on August 13, Mitsuda called a meeting of the patients and warned them against misconduct.

Dining hour was thus delayed, and in the middle of the night, patients gathered and got excited; demonstrations took place, with some people refusing to do their assigned work.

After 10 days of heated negotiations with officials from the Interior Ministry, the Police Department of Okayama Prefecture, the Special Police Section and Mitsuda, the patients were permitted to form Jichikai (a patients' association), a kind of self-governing organization.

On May 9, 1988, the mainland and the islands of Nagashima Aiseien and Oku Komyoen were joined upon completion of the Oku-Nagashima-Ohashi Bridge.