{
  "abstract": "Objective This study aims to describe the characteristics of hospitalised COVID-19 patients in a tertiary care hospital close to an international airport in Japan and to compare these characteristics among different waves during the pandemic.Design Retrospective observational study.Setting Tertiary care centre in Japan.Participants All patients diagnosed with COVID-19 who were hospitalised between January 2020 and April 2022 were included.Measurements Clinical characteristics, characteristics of admission, treatments and outcomes were investigated and compared among six pandemic waves.Results A total of 827 patients were included. The median age was 58.0 years. More than half of the patients (58.3%) had at least one comorbidity. The majority of patients (89.0%) were domestically infected patients admitted under the Infectious Diseases Law, while the remaining patients (11.0%) were those diagnosed during airport quarantine and admitted under the Quarantine Act. Hospital-acquired COVID-19 infection occurred in 7.0% of cases, and mainly during the sixth wave. Overall, some form of oxygen therapy, high-flow oxygen devices, invasive mechanical ventilation (IMV) and extracorporeal membrane oxygenation was provided in 46.3%, 10.4%, 4.5% and 1.5% of cases, respectively. Only 1.8% of patients were treated in the intensive care unit (ICU), and 59.5% of patients on IMV were managed in the non-ICU ward. The in-hospital mortality rate was 5.8%. Median age, percentages of some comorbidities, vaccination coverage, medications for COVID-19, types of supportive care and ICU admissions differed significantly among waves.Conclusions This study suggests that patient characteristics, vaccination coverage, standard of treatment and severity of illness changed across waves during the COVID-19 pandemic. Intensive care delivery in non-ICU wards was unavoidable due to limited ICU capacity, which may be a key consideration when preparing for future pandemics.",
  "authors": [
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Infectious Diseases, Kameda Medical Center, Kamogawa, Chiba, Japan"
      ],
      "name": "Ryota Hase"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Infectious Diseases, Kameda Medical Center, Kamogawa, Chiba, Japan"
      ],
      "name": "Rika Kurata"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of General Internal Medicine, Matsuyama Red Cross Hospital, Matsuyama, Ehime, Japan"
      ],
      "name": "Yu Niiyama"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Embassy of Japan in Nigeria, Abuja, Nigeria"
      ],
      "name": "Naoya Matsuda"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Emergency Medicine and General Internal Medicine, Fujita Health University School of Medicine, Toyoake, Aichi, Japan"
      ],
      "name": "Hideki Ueda"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Infectious Diseases, Teine Keijinkai Hospital, Sapporo, Hokkaido, Japan"
      ],
      "name": "Koki Kikuchi"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Infectious Diseases, Kameda Medical Center, Kamogawa, Chiba, Japan"
      ],
      "name": "Keiko Ishida"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Emergency and Critical Care Medicine, National Hospital Organization Nagasaki Medical Center, Omura, Nagasaki, Japan"
      ],
      "name": "Yoshifumi Kubota"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Infectious Diseases, Kameda Medical Center, Kamogawa, Chiba, Japan",
        "Department of Intensive Care Medicine, Kameda Medical Center, Kamogawa, Chiba, Japan"
      ],
      "name": "Motoki Fujii"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Infectious Diseases, Institute of Science Tokyo, Bunkyo, Tokyo, Japan"
      ],
      "name": "Takashi Kurita"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan"
      ],
      "name": "Emiri Muranaka"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Internal Medicine/Infectious Diseases, Omachi Municipal General Hospital, Omachi, Nagano, Japan"
      ],
      "name": "Hiroki Sasazawa"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan"
      ],
      "name": "Haruki Mito"
    },
    {
      "affiliations": [
        "Department of Infectious Diseases, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Internal Medicine, Sekishinkan Hospital, Komatsushima, Tokushima, Japan"
      ],
      "name": "Yudai Yano"
    },
    {
      "affiliations": [
        "Department of Emergency and Critical Care Medicine, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Critical Care Medicine, Japanese Red Cross Kumamoto Hospital, Kumamoto, Japan"
      ],
      "name": "Reiko Oku"
    },
    {
      "affiliations": [
        "Department of Emergency and Critical Care Medicine, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Department of Emergency and Critical Care Medicine, Chiba Kaihin Municipal Hospital, Chiba, Japan"
      ],
      "name": "Yoshihisa Tateishi"
    },
    {
      "affiliations": [
        "Department of Neonatology, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan"
      ],
      "name": "Satoshi Toishi"
    },
    {
      "affiliations": [
        "Department of Obstetrics and Gynecology, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan"
      ],
      "name": "Shintaro Obata"
    },
    {
      "affiliations": [
        "Department of Pediatrics, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan"
      ],
      "name": "Yasushi Noguchi"
    },
    {
      "affiliations": [
        "Department of Emergency and Critical Care Medicine, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan",
        "Meiseikai Toyo Clinic Airport, Tomisato, Chiba, Japan"
      ],
      "name": "Kazuya Nakanishi"
    },
    {
      "affiliations": [
        "Department of Pediatrics, Japanese Red Cross Narita Hospital, Narita, Chiba, Japan"
      ],
      "name": "Shosuke Sunami"
    }
  ],
  "title": "Clinical characteristics, treatments and outcomes of hospitalised COVID-19 patients across pandemic waves at a tertiary acute care hospital in Narita, Japan: a single-centre retrospective observational study",
  "uid": "a682bfdc-b304-534c-9f4e-f9ea989c3789"
}