[Outcomes of COVID-19 due to omicron variant infection complicated with hematological disorders].

When the omicron variant became the most dominant severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) variant causing coronavirus disease 2019 (COVID-19) in Japan, 11 patients with hematological diseases infected with this new variant were treated at our institution. Among them, four of the five patients who had been treated with chemotherapy progressed to moderate-II COVID-19, and two of them died. In contrast, five of the six patients who did not receive the treatment remained at mild to moderate-I stage of COVID-19, except for a single case progressing to moderate-II COVID-19. While all four patients infused with anti-coronavirus monoclonal antibodies within 8 days after the onset survived, the other two patients, being withheld from treatment or treated later, died. In these two cases, anti-SARS-Cov-2 immunoglobulin G antibodies remained at low titers. Although the omicron variant is considered a less harmful SARS-Cov-2 variant, patients with hematological disorders, particularly those who are immunosuppressed caused by chemotherapy, should be continuously cared for as they remain at a higher risk of severe COVID-19 due to insufficient or delayed anti-viral humoral immunity development. Thus, the rapid introduction of antiviral monoclonal antibodies together with anti-viral reagents may rescue these patients.

Nationwide descriptive epidemiological study of patients with COVID-19 evacuated from Wuhan, China, to Japan from January to February 2020.

We investigated epidemiological findings regarding the route of coronavirus disease 2019 (COVID-19) and infection prevention and control (IPC) measures among returnees in the emergent evacuation from Wuhan, China to Japan under the COVID-19 outbreak in 2020. A total of 12 of 14 returnees (median age [range]: 49.5 years [29-65 years]; 9 men [75%]) were confirmed COVID-19. The proportions of returnees with COVID-19 were 12/566 (2.1%) in the 1-3 flights and 2/263 (0.8%) in the 4-5 flights. Six patients were asymptomatic on admission, while three patients developed symptoms thereafter. None reported a specific history of contact with animals, going to seafood markets, or visiting medical facilities. Two patients contacted with an individual confirmed or suspected to have COVID-19, respectively. Most patients resided in hotels in the center of Wuhan city, taking taxis and trains to work and supermarkets. Patients relatively adhered to IPC measures such as wearing a mask and hand hygiene. However, emphasis on IPC measures such as universal masking and more rigorous avoidance of exposure risk may have been necessary to prevent infection. In addition, forced social distancing due to lockdown might contribute to the lower infection rates in Flights 4 and 5, compared to Flights 1-3.

Number of Patients with Influenza and COVID-19 Coinfection in a Single Japanese Hospital during the First Wave.

An individual may contract coronavirus disease 2019 (COVID-19) and influenza simultaneously; hence, adequate measures must be undertaken for the next winter in Japan. In preparation for the future, this study aimed to clarify the incidence of influenza coinfection in patients with COVID-19 during the previous winter. We conducted a retrospective study of the medical records of 193 patients diagnosed with COVID-19 between January 31, 2020, and April 23, 2020, in a single hospital. We evaluated the incidence of COVID-19 and influenza coinfection. Using rapid diagnostic testing, we found that no patient with COVID-19 was coinfected with influenza. Coinfection with influenza and COVID-19 was rare during the past winter in Japan.

Proactive Engagement of the Expert Meeting in Managing the Early Phase of the COVID-19 Epidemic, Japan, February-June 2020.

To deal with the risk of emerging diseases with many unknowns, close and timely collaboration and communication between science experts and policymakers are crucial to developing and implementing an effective science-based intervention strategy. The Expert Meeting, an ad hoc medical advisory body, was established in February 2020 to advise Japan's COVID-19 Response Headquarters. The group played an important role in the policymaking process, promoting timely situation awareness and developing science-based proposals on interventions that were promptly reflected in government actions. However, this expert group may have been overly proactive in taking on the government's role in crisis management. For the next stage of managing the coronavirus disease pandemic and future pandemics, the respective roles of the government and its advisory bodies need to be clearly defined. Leadership and strategic risk communication by the government are key.

Development of a Risk Prediction Score to Identify High-Risk Groups for the Critical Coronavirus Disease 2019 (COVID-19) in Japan.

Coronavirus disease 2019 (COVID-19) emerged in mid-December 2019 and has rapidly spread worldwide. We conducted a retrospective analysis of data from patients with COVID-19 to construct a simple risk prediction score to be implemented in prehospital settings. Patients were classified into critical and non-critical groups based on disease severity during hospitalization. Multivariate analysis was performed to identify independent risk factors and develop a risk prediction score. A total of 234 patients were included in the study. The median age of the critical group was significantly older than that of the non-critical group (68.0 and 44.0 years, respectively), and the percentage of males in the critical group was higher than that in the non-critical group (90.2% and 60.6%, respectively). Multivariate analysis revealed that factors such as age ≥ 45 years, male sex, comorbidities such as hypertension and cancer, and having fever and dyspnea on admission were independently associated with the critical COVID-19 infection. No critical events were noted in patients with a total risk factor score of ≤ 2. Contrastingly, patients with a total risk factor score ≥ 4 were more likely to have critical COVID-19 infection. This risk prediction score may be useful in identifying critical COVID-19 infections.

An analysis of the radiological factors associated with respiratory failure in COVID-19 pneumonia and the CT features among different age categories.

PURPOSE: To investigate CT patterns of COVID-19 pneumonia associated with respiratory failure (RF) focused on the distribution of lesions. MATERIALS AND METHODS: Eighty-five patients with COVID-19 pneumonia were reviewed. CT findings were classified as follows: Type A; patchy ground glass attenuation (GGA) with/without air-space consolidation, Type B; non-segmental GGA with/without air-space consolidation in both the central and peripheral lung portions especially with subpleural spare, and Type C; non-segmental GGA with/without air-space consolidation predominantly distributed in the peripheral lung portion without subpleural spare. We analyzed CT patterns and clinical factors associated with RF, including age categories. RESULTS: The number of patients with Type A, B and C was 31 (37%), 24 (28%) and 30 (35%), respectively. Type C and hypertension were independently associated with RF. On comparing between Types B and C, the frequency of traction bronchiectasis was higher in Type C than in Type B (P < 0.001). The ratio of Type C in patients ≥ 65 years old (66%) was higher than in patients < 40 years old (P < 0.001) and 40-49 years old (P = 0.001). CONCLUSION: The Type C, increasing with age, was associated with RF. Traction bronchiectasis in the lesion was more frequent in Type C than in Type B. Secondary abstract A lesion adjacent to the pleura and hypertension is associated with respiratory failure in patients with COVID-19. The frequency of a lesion adjacent to the pleura increased with age. The distribution of lesions is a useful parameter to predict respiratory failure.

Prevalence of thromboembolic events and status of prophylactic anticoagulant therapy in hospitalized patients with COVID-19 in Japan.

INTRODUCTION: One of the most prominent and concerning complications associated with coronavirus disease 2019 (COVID-19) is venous and arterial thromboembolisms. The aim of the present study was to delineate the prevalence of thromboembolic events and the current status of prophylactic anticoagulation therapy in patients with COVID-19 in Japan. METHODS: Between February 1 and August 31, 2020, we performed a dual-center, retrospective cohort study based on data obtained from the medical charts of COVID-19 patients admitted to healthcare facilities in Japan. The primary outcome was any thromboembolic event including pulmonary embolism (PE), deep vein thrombosis (DVT), myocardial infarction, ischemic stroke and other systemic thromboemboli. RESULTS: During the study period, we extracted 628 consecutive patients admitted for COVID-19. Prophylactic anticoagulant therapy was administered in 63 (10%) patients of whom 20 (31.7%) were admitted to the intensive care unit (ICU). Thromboembolic events occurred in 18 (2.9%) patients (14.3% of patients in ICU and 2.2% of patients in the general wards). DVT were detected in 13 (2.1%) patients, PE in 11 (1.8%), and both DVT and PE in 6 (0.96%) patients. An increasing prevalence in thromboembolic events was noted with progressive clinical severity. Overall in-hospital mortality was 4.8%. CONCLUSIONS: Prophylactic anticoagulation therapy was administered in only 10% of all hospitalized COVID-19 patients. The prevalence of any thromboembolic events was 2.9% in COVID-19 patients with most events occurring in severe and critical patients. Therefore, prophylactic anticoagulation therapy may be warranted in severe and critical patients but in asymptomatic to moderate patients the practice remains controversial.

Characteristics and outcomes of coronavirus disease 2019 (COVID-19) patients with cancer: a single-center retrospective observational study in Tokyo, Japan.

BACKGROUND: Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused an international outbreak of coronavirus disease 2019 (COVID-19), data on the clinical characteristics of COVID-19 patients with cancer are limited. This study aimed to evaluate the clinical characteristics and outcomes including mortality and viral shedding period in COVID-19 patients with cancer in Japan. METHODS: We retrospectively analyzed 32 patients with a history of cancer who were referred to our hospital between January 31, 2020 and May 25, 2020. We evaluated the association between clinical outcomes and potential prognostic factors using univariate analyses. RESULTS: The median age was 74.5 (range 24-90) years and 22 patients (69%) were men. A total of 11 patients (34%) died. Our analyses demonstrated that the mortality was significantly associated with lymphocyte count, albumin, lactate dehydrogenase, serum ferritin, and C-reactive protein on admission. The median period between illness onset and the first effective negative SARS-CoV-2 PCR result was 22 days (interquartile range 18-25) in survivors. Of four patients with hematological malignancy who developed COVID-19 within the rest period of chemotherapy, three died and the other patient, who received bendamustine plus rituximab therapy, had the longest duration of viral shedding (56 days). CONCLUSION: Our study suggested that the risk factors for mortality previously reported in general COVID-19 patients, including lymphocytopenia, were also effective in cancer patients. Patients who received cytotoxic chemotherapy recently or were treated with chemotherapy, which can lead to lymphocyte reduction, had poor prognosis and prolonged periods of viral shedding.

SARS-CoV-2 Screening Test for Japanese Returnees From Wuhan, China, January 2020.

BACKGROUND: Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) was found to be the causative microorganism of coronavirus disease 2019 (COVID-19), which started to spread in Wuhan, China. This study was to evaluate the effectiveness of questionnaire, symptoms-based screening, and polymerase chain reaction (PCR) screening of returnees from COVID-19-endemic areas on a chartered flight, to examine the proportion of infected persons and the proportion of asymptomatic persons among infected persons who returned from Wuhan. METHODS: A retrospective cohort study was done in 7 tertiary medical institutions in Japan. A total of 566 Japanese who returned from Wuhan participated in the study. RESULTS: Overall, 11 of the 566 passengers had a positive SARS-CoV-2 PCR result for pharyngeal swabs and 6 were asymptomatic. Only fever differed between SARS-CoV-2-positive and -negative individuals (P < .043). Six of the 11 PCR-positive individuals were asymptomatic; 4 remained positive on day 10, and 1 asymptomatic person tested positive up to day 27. Two of the 11 were negative on the first PCR test and positive on the second. CONCLUSIONS: Our results will be important insights on screening returnees from locked-down cities, as well as providing important data on the proportion of asymptomatic individuals infected with SARS-CoV-2. A 13-day observation period and a second round of PCR may be effective to screen patients, including asymptomatic infections.