[Special Feature: The COVID Crisis and the University] Records of Nosocomial Infection Control at Keio University Hospital / Naoki Hasegawa

COVID-19, an emerging infectious disease caused by SARS-CoV-2 (novel coronavirus) that originated in Wuhan, Hubei Province, China, in December 2019, was designated as a legal infectious disease. At Keio University Hospital, the decision to establish a response headquarters headed by the Hospital Director was made on February 5, and information gathering and countermeasure planning began. As a cooperating medical institution for infectious disease treatment in Tokyo, our hospital prepared two former negative-pressure tuberculosis beds and established a response system.

In February, our hospital accepted its first mild cases of COVID-19 from the cruise ship Diamond Princess in Yokohama Port. Furthermore, we renovated closed clinical spaces and the emergency department to account for infection control, including patient flow and zoning. We established a medical system based on severity, centered on the Department of Pulmonary Medicine and the Emergency Department, managed pneumonia patients in private rooms, and monitored the number of faculty and staff with fevers at the Health Center and the number of inpatients with fevers at our department. On February 27, through the efforts of the clinical laboratory department, an in-hospital system for PCR testing was established.

Keeping in mind the existence of infectious asymptomatic carriers, we banned international travel for students and medical professionals starting March 9, and from March 18, we banned all returnees from overseas from entering the Shinanomachi Campus for 14 days. However, on March 19, a patient who had transferred to our hospital after confirming they were asymptomatic and had no pneumonia on chest CT tested positive for PCR on the 23rd. Infections were discovered in four patients, including three roommates, and four healthcare workers. We closed other wards and continued medical care in the affected ward with its own staff, but a subsequent investigation revealed that multiple roommates at the previous hospital had developed COVID-19 and were already infected at the time of transfer.

In the midst of this, on March 31, several junior residents developed fevers simultaneously, and one was found to be PCR positive at another hospital. Prepared for the great inconvenience to those involved, the Hospital Director made the bold decision to stop all junior residents from starting work the next day. Furthermore, considering the possibility of contact with them, we temporarily suspended the off-campus work of all doctors at our hospital. Contacting each department and individual lasted late into the night, but as a result, this response—which managed to stop the spread of infection to other facilities originating from our hospital just in time—became the ultimate infection control measure. Later, it was revealed to be a cluster infection among residents via an informal dinner party held by some of them. From these two clusters occurring inside and outside the hospital, we realized the dread of infectious diseases and the difficulty of infection control.

Although outpatient and inpatient medical services were significantly reduced, since there are no vaccines or effective drugs for SARS-CoV-2, we focused on breaking the chain of infection and made thorough efforts to ensure people do not get infected, do not infect others, and do not spread the infection.

For the early detection of infected individuals, we made maximum use of the in-hospital PCR testing system, actively testing all scheduled inpatients and symptomatic individuals; the number of in-house PCR tests performed was among the highest in the country. Stockpiles of personal protective equipment (PPE) essential for infection control were rapidly consumed, and like other hospitals, the shortage was serious. However, we placed them under the management of the Center for Infectious Disease and Infection Control, provided guidance on appropriate use to gain understanding, and proceeded with making handmade gowns processed from plastic bags. Infection through the eyes drew attention, and we ensured thorough eye protection during aerosol generation. While eye guards were also in short supply, we were greatly helped by the provision of face shields with headbands made by 3D printers from related research institutions. Infection control nurses who trained in our department were temporarily assigned to promote training on the correct way to put on and take off PPE.

Since the virus is also contained in saliva, dining and conversations that generate droplets were considered infection risks. We notified both patients and medical staff to wear masks, avoid the so-called "Three Cs" (Closed spaces, Crowded places, Close-contact settings), and practice social distancing, and conducted rounds to ensure compliance. However, as a measure against the virus that survives for a long time on environmental surfaces, hand washing and hand hygiene are fundamental. We are working to ensure this through the setting of reinforcement periods, mutual reminders, and video messages from department heads. For cleaning hospital rooms after discharge, we introduced a disinfection system using ultraviolet radiation.

In addition, self-health management of medical professionals themselves, who are constantly exposed to infection risks, is important. We ensured that people perform self-temperature checks and stay home to consult when they have a fever or feel unwell. Furthermore, the systems department is developing a system for entering temperatures online via the intranet, and we are proceeding with third-party temperature checks and the installation of high-sensitivity, rapid temperature sensors in the outpatient department.

The occurrence of COVID-19 clusters inside and outside the hospital caused great inconvenience and concern to many people, but we would like to express our sincere gratitude and appreciation for the warm words of encouragement and support from many members of the Juku and benefactors. Moving forward, the Hospital Director and all staff will continue to work together on infection control measures, balancing COVID-19 treatment with our duties as an Advanced Treatment Hospital to fulfill our responsibilities.