Infectious Diseases

What we do

The Department of Infectious Diseases provides comprehensive internal medicine care for all types of microbial infections—regardless of age, gender, affected organ, or pathogen type (bacteria, viruses, fungi, or parasites).

In addition to managing complex in-hospital infections and antimicrobial stewardship, our specialized Travel Medicine & Vaccination Clinic supports international travelers, expatriates, and patients with chronic health conditions before and after global travel.

Key Clinical Focus Areas

1. In-Hospital ID Consultations & Co-Management

Specialized Infectious Disease Consultation: We collaborate with primary attending physicians to identify hidden infections, manage severe organ-specific infections (pneumonia, complicated UTIs, catheter infections), and tailor optimal antimicrobial regimens for immunocompromised or complex patients.

Mandatory Blood Culture Co-Management: When blood cultures yield positive results (bacteremia/fungemia), our ID specialists automatically co-manage the patient alongside the primary team. Early intervention prevents progression to severe sepsis, septic shock, and multi-organ failure.

Antimicrobial Stewardship: To combat the global rise of Drug-Resistant Organisms (Superbugs), we promote rational antibiotic use—avoiding empirical overuse, utilizing targeted microbiological diagnostics, and safeguarding last-resort reserve antibiotics.

Specialized Direct Care: Our ID specialists serve as primary attending physicians for high-complexity infectious diseases requiring long-term, expert management, such as HIV/AIDS, Tuberculosis (TB), Malaria, and Dengue Fever.

Hospital Infection Control: In partnership with the Regional Center for Disease Control & Prevention and the Infection Control Team (ICT), we oversee hand hygiene, seasonal influenza control, and environmental infection prevention hospital-wide.

2. Travel Medicine & Vaccination Clinic

Pre-Travel Consultation & Tailored Vaccines: Expert assessment of travel destinations (tropical regions, jungles, high-altitude areas) to recommend and administer required/recommended travel vaccines. (Note: Some vaccine schedules take up to 6 months to complete, so early consultation is encouraged).

Malaria Chemoprophylaxis & Vector Protection: Prescription of malaria preventive medications and vector-borne disease precautions (Dengue, Chikungunya, Zika).

High-Altitude Sickness Prevention: Prophylaxis medications and travel scheduling advice for high-altitude destinations.

Travel with Chronic Conditions & Special Populations: Pre-travel health evaluations and medication timing adjustments (e.g., jet lag management for insulin) for seniors, pregnant women, children, and individuals with chronic diseases (hypertension, diabetes).

Post-Travel Illness & Tropical Medicine: Specialized diagnostic evaluation and treatment for post-travel fevers, diarrhea, or unusual symptoms occurring within 3 months (or longer) after returning to Japan.

Travel Medicine Outpatient Guidance

What to Bring to Your Vaccination Consultation: Please bring your Maternal and Child Health Handbook or previous immunization records if available. This allows our specialists to verify your past vaccination history accurately.

Altitude Sickness Notice: If traveling to regions with elevations exceeding $3,000\text{ meters}$, specialized preventive oral medications can be prescribed prior to departure to minimize headaches, fatigue, and acute mountain sickness (AMS).

Conditions we handle

Diseases Co-Managed with Primary Clinical Teams

Bacteremia, Sepsis & Cardiovascular: Bacteremia, septic shock, infective endocarditis, mediastinitis, septic thrombophlebitis, catheter-related bloodstream infections (CRBSI).

Central Nervous System: Bacterial/viral meningitis, brain abscess, encephalitis, epidural abscess.

Respiratory & Head/Neck: Pneumonia, lung abscess, empyema, pharyngitis, tonsillitis, peritonsillar abscess, malignant otitis externa, endophthalmitis.

Abdominal & Gastrointestinal: Cholecystitis, cholangitis, liver abscess, infectious enteritis, Clostridioides difficile colitis, diverticulitis, appendicitis.

Urinary & Pelvic: Pyelonephritis, cystitis, prostatitis, urethritis, pelvic inflammatory disease (PID).

Musculoskeletal & Soft Tissue: Septic spondylodiscitis, septic arthritis, osteomyelitis, muscle abscess, cellulitis, necrotizing fasciitis, lymphadenitis, pressure ulcer infections, surgical site infections (SSI).

Systemic, Viral & Special Infections: Febrile neutropenia, syphilis, tetanus, nocardiosis, influenza, measles, rubella, varicella (chickenpox), herpes zoster (shingles), cytomegalovirus (CMV), Epstein-Barr virus (EBV).

Number of cases

（2024）
Number of outpatients: about 9,552/year
Number of inpatient: 1,075/year

List of Doctors

Chief, Department of Laboratory Medicine; Chief, Department of Infectious Diseases; Chief, Regional Infectious Disease Surveillance and Prevention Center

Naoto HOSOKAWA

Subspeciality
Department of General Medicine: general internal medicine, general infectious diseases, diseases with fever, diseases caused by microorganisms
Department of Infectious Diseases: diseases caused by microorganisms, travel medicine
Department of Laboratory Medicine: laboratory medicine, management of clinical laboratory
Education of regidents

Department name	Infectious Diseases
Medical School	Nihon University
Special Qualifications	Board Certified Member of the Japanese Society of Internal Medicine, Fellow of the Japanese Society of Internal Medicine (FJSIM), JSIM appointed physician for fellowship training Board Certified Member / Supervising Physician of the Japanese Association for Infectious Diseases Board Certified Member of the Japanese Society of Laboratory Medicine Infection Control Doctor certified by the Japanese Committee for Infection Control Doctors Japanese Antimicrobial Chemotherapy Physician (JACP), Fellow of JACP Certified Physician of the Japanese Society for Clinical Microbiology Medical worker certified by the Japanese Society of Travel and Health M.D., Ph.D.
Education & Career	Mar 1990: Nihon University School of Medicine May 1990: Resident, Nihon University Itabashi Hospital May 1992: Assistant, Division of Pediatrics, Department of Medicine, Nihon University School of Medicine May 1993: Department of Clinical Pathology (currently Department of Clinical Laboratory Medicine), Nihon University School of Medicine May 2005: Joined to Department of Infectious Diseases, Kameda Medical Center Aug 2005: Assistant Chief, Department of Infectious Diseases Jul 2006: Chief, Department of Laboratory Medicine; Assistant Chief, Department of General Medicine / Infectious Diseases Apr 2006: Chief, Department of Laboratory Medicine; Deputy Chief, Department of General Medicine / Infectious Diseases Feb 2009: Chief, Department of Laboratory Medicine; Deputy Chief, Department of General Medicine / Infectious Diseases; Chief, Infection Control Room Apr 2010: Chief, Department of Laboratory Medicine; Chief, Department of General Medicine / Infectious Diseases; Chief, Infection Control Room Jul 2013: Chief, Department of Laboratory Medicine; Chief, Department of General Medicine / Infectious Diseases; Chief, Regional Infectious Disease Surveillance and Prevention Center pr 2014: Chief, Department of Laboratory Medicine; Chief, Department of Infectious Diseases; Chief, Regional Infectious Disease Surveillance and Prevention Center Jun 2023: Chief, Department of Laboratory Medicine; Chief, Department of Infectious Diseases; Chief, Regional Infectious Disease Surveillance and Prevention Center

Chief, Department of Infectious Diseases (being seconded to other hospital)

Ryota HASE

Subspeciality
Infectious Disease，General Medicine，Outpatient Parenteral Antimicrobial Therapy（OPAT）

Department name	Infectious Diseases
Medical School	Kanazawa University
Special Qualifications	Board Certified Member of the Japanese Society of Internal Medicine, Fellow of the Japanese Society of Internal Medicine (FJSIM) Board Certified Member of the Japanese Association for Infectious Diseases Certificate in Travel Health, International Society of Travel Medicine Infection Control Doctor certified by the Japanese Committee for Infection Control Doctors
Education & Career	Mar 2005: Graduated from School of Medicine, Kanazawa University Apr 2005: Junior Resident, Teine Keijinkai Hospital Apr 2008: Joined Kameda Medical Center as Senior Resident, Department of General Medicine / Infectious Diseases Apr 2010 : Fellow, Department of General Medicine / Infectious Diseases Apr 2012: Staff Physician, Department of General Medicine / Infectious Diseases Apr 2014: Assistant Chief, Department of General Medicine / Infectious Diseases Apr 2014: Deputy Chief, Department of Infectious Diseases Jul 2015: Seconded to Japanese Red Cross Narita Hospital Apr 2016: Chief, Department of Infectious Diseases; Being seconded to Japanese Red Cross Narita Hospital Jun 2023: Chief, Department of Infectious Diseases; Being seconded to Japanese Red Cross Narita Hospital

Chief, Department of Infectious Diseases

Ryosuke OSAWA

Subspeciality
General infectious diseases, transplant infectious diseases, tuberculosis

Department name	Infectious Diseases
Medical School	Tokyo University
Special Qualifications	ABIM Board Certified in Internal Medicine ABIM Board Certified in Infectious Diseases Certificate in Travel Health, International Society of Travel Medicine Board Certified Member / Supervising Physician of the Japanese Association for Infectious Diseases Board Certified Member of the Japanese Society of Internal Medicine Completed “Clinical Training Instructor Workshop” hosted by the Ministry of Health, Labour and Welfare
Education & Career	Mar 2001: Graduated from Faculty of Medicine, Tokyo University Apr 2001: Medical Intern, US Naval Hospital Yokosuka Jun 2002: Resident, Department of Internal Medicine, The University of Tokyo Hospital Jul 2003: Resident, Department of Internal Medicine, Beth Israel Medical Center Jul 2006: Chief Resident, Department of Internal Medicine, Beth Israel Medical Center Jul 2007: Fellow, Department of Infectious Diseases, University of Pittsburgh Jul 2008: Master of Science in Clinical Research, University of Pittsburgh School of Medicine Jul 2009: Fellow, Department of Transplant Infectious Diseases, University of Pittsburgh Aug 2010: Assistant Professor, Department of Internal Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo Aug 2010: Staff, Department of Infectious Diseases, Buffalo General Medical Center Aug 2010: Staff, Department of Infectious Diseases, Roswell Park Comprehensive Cancer Center Jan 2013: Medical co-Director, Erie County Department of Health (ECDOH) Tuberculosis (TB) Clinic Sep 2018: Joined Kameda Medical Center as Deputy Chief, Department of Infectious Diseases Sep 2019: Chief, Department of Infectious Diseases Jun 2023: Chief, Department of Infectious Diseases

Deputy Chief, Department of Infectious Diseases

Yosuke EBISU

Subspeciality
Internal medicine, infectious diseases, transplant infectious diseases

Department name	Infectious Diseases
Medical School	Kyoto Prefectural University of Medicine
Special Qualifications	Board Certified Member of the Japanese Society of Internal Medicine Board Certified Member of the Japanese Society of Internal Medicine, General Internal Medicine Board Certified Member of the Japanese Association for Infectious Diseases ABIM Board Certified in Internal Medicine ABIM Board Certified in Infectious Diseases
Education & Career	Mar 2005: Graduated from Kyoto Prefectural University of Medicine, School of Medicine Apr 2005: Junior Resident, Shonan Kamakura General Hospital Apr 2007: Department of General Medicine / Infectious Diseases, Kameda Medical Center Apr 2010: Department of Internal Medicine, Awa Regional Medical Center Apr 2011: Medical Intern, US Naval Hospital Yokosuka Apr 2012: Department of Internal Medicine, Nerima Hikarigaoka Hospital Jul 2013: Fellowship program, Department of Infectious Diseases, University of New Mexico Jul 2015: Residency program, Department of Internal Medicine, University of New Mexico Jul 2018: Fellowship program, Department of Transplant Infectious Diseases, Jackson Memorial Hospital, University of Miami Aug 2019: Joined Kameda Medical Center as Deputy Chief, Department of General Medicine Aug 2022: Deputy Chief, Department of Infectious Diseases Jun 2023: Deputy Chief, Department of Infectious Diseases

Assistant Chief, Department of Infectious Diseases

Takeru YAMAMOTO

Subspeciality
Infectious diseases, internal medicine

Department name	Infectious Diseases
Medical School	Aichi Medical University
Special Qualifications	Fellow of the Japanese Society of Internal Medicine (FJSIM)
Education & Career	Mar 2007: Graduated from School of Medicine, Aichi Medical University Apr 2007: Junior Resident, Seirei Mikatahara General Hospital Apr 2009: Sinior Resident, Department of General Medicine / Infectious Diseases, Kameda Medical Center Jul 2013: Research Fellow, Department of Infectious Diseaseas, Mount Sinai Beth Israel Aug 2016: Department of General Medicine, Aichi Medical University Hospital Sep 2019: Fellowship, Department of Infectious Diseases, University of Missouri-Kansas City Jan 2022: Joined Kameda Medical Center as Staff Physician, Department of Infectious Diseaseas Apr 2022: Assistant Chief, Department of Infectious Diseaseas Jun 2023: Assistant Chief, Department of Infectious Diseaseas