Yet another outbreak of hospital-acquired group infection caused by serratia bacteria has occurred. At a hospital in Tokyo's Setagaya Ward, a total of 12 inpatients on the same floor were infected, and seven of them died within a week. This is an extremely serious case of medical error.

Previously, serratia bacteria infection broke out at hospitals in Tokyo's Sumida Ward in 1999 and Sakai in Osaka Prefecture in 2000, leading to the deaths of five and eight inpatients, respectively. Although both of these were very serious incidents, the lessons obviously have not been learned. There must have been a common cause.

An investigation should be thorough and unambiguous, and the results made public without delay. Measures against nosocomial infection must be strengthened at hospitals and clinics throughout the country. If people do not feel safe going to see the doctor, then their trust in medical treatment is going to collapse.