Transition of antibody titers after the SARS-CoV-2 mRNA vaccine in Japanese healthcare workers.

Since February 2021, healthcare workers in Japan have been preferentially vaccinated with a messenger RNA vaccine (BNT162b2/Pfizer) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While many studies have confirmed that this vaccine is highly effective in reducing hospitalizations and deaths from coronavirus disease 2019 (COVID-19), antibody titers tend to decline at 3 months, leading to a risk of breakthrough infections. Thus, information is needed to support decision making regarding the third vaccination. In this study, we investigated transition of the anti-SARS-CoV-2 spike protein receptor-binding domain (RBD) IgG and neutralizing antibody titers of 37 vaccinated Japanese healthcare workers. Samples were collected six times starting prevaccination until 6 months after the second vaccination. Anti-SARS-CoV-2 RBD IgG levels peaked at 1 week after the second vaccination, then declined over time and decreased to <10% at 6 months after the second vaccination. Additionally, approximately one third of subjects at 6 months after the second vaccination were seronegative for the Omicron variant. Workers with low anti-SARS-CoV-2 RBD IgG levels also had low neutralizing antibody titers. These data support the active use of boosters for healthcare workers, especially for those with low anti-SARS-CoV-2 RBD IgG levels.

Sensitivity and specificity analyses of COVID-19 screening protocol for emergency medical services: A STARD-compliant population-based retrospective study.

During the novel coronavirus disease (COVID-19) pandemic, emergency medical services (EMS) has borne a huge burden in transporting emergency patients. However, the protocol's effect on identifying emergency patients who are likely to have COVID-19 is unknown. We aimed to evaluate the diagnostic accuracy of a prehospital COVID-19 screening protocol for EMS. We conducted this population-based retrospective study in Nara Prefecture, Japan. The Nara Prefectural Government implemented a screening protocol for COVID-19 comprising the following symptom criteria (fever, cough, sore throat, headache, malaise, dysgeusia, or anosmia) and epidemiological criteria (contact history with confirmed COVID-19 cases or people with upper respiratory symptoms, or travel to areas with high infection rate). A patient meeting at least one criterion of each class was considered positive. We evaluated all 51,351 patients from the regional EMS database of the Nara Prefecture (emergency Medical Alliance for Total Coordination of Healthcare) who were registered from June 15, 2020 to May 31, 2021 and had results of COVID-19 reverse transcription polymerase chain reaction (RT-PCR) tests. We assessed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of this protocol. We also assessed how these outcomes changed by adding vital signs and conducted a 10-fold and 100-fold prevalence simulation. The screening protocol was used for 246/51351 patients (0.5%). Among them, 31 tested positive after EMS transportation. This protocol's sensitivity, specificity, PPV, and NPV were 40.8%, 99.6%, 12.6%, and 99.9%, respectively. With the addition of ≥2 vital signs (body temperature ≥37.5 °C, respiratory rate ≥20 breaths/minute, and oxygen saturation <90%), sensitivity and PPV changed to 61.8% and 1.0%, respectively, while NPV remained 99.9%. With a 10-fold and 100-fold increase in disease, the protocol PPV would be 59.0% and 94.3%, and NPV would be 99.1% and 90.7%, respectively, and with additional vital signs, PPV would be 8.9% and 53.1%, and NPV would be 99.4% and 93.2%, respectively. This COVID-19 screening protocol helped enable EMS transport for patients with COVID-19 with a PPV of 12.6%. Adding other vital sign variables may improve its diagnostic value if the prevalence rate increases.

The balance of comprehensive coagulation and fibrinolytic potential is disrupted in patients with moderate to severe COVID-19.

Coagulation and fibrinolytic mechanisms are enhanced in patients with coronavirus (COVID-19), but disturbances in the balance of both functions in COVID-19 patients remain unclear. We assessed global coagulation and fibrinolysis in plasma from 167 COVID-19 patients (mild/moderate/severe: 62/88/17, respectively) on admission using clot-fibrinolysis waveform analysis (CFWA). Maximum coagulation velocity (|min1|) and maximum fibrinolysis velocity (|FL-min1|) were expressed as ratios relative to normal plasma. Ten patients (6.0%) developed thrombosis, 5 (3.0%) had bleeding tendency, and 13 (7.8%) died during admission. FDP levels increased with severity of COVID-19 symptoms (mild/moderate/severe; median 2.7/4.9/9.9 µg/mL, respectively). The |min1| ratios were elevated in all categories (1.27/1.61/1.58) in keeping with enhanced coagulation potential, with significant differences between mild cases and moderate to severe cases. The |FL-min1| ratios were also elevated in all groups (1.19/1.39/1.40), reflecting enhanced fibrinolytic potential. These data identified coagulation dominance in moderate to severe cases, but balanced coagulation and fibrinolysis in mild cases. There were significant differences in FDP and TAT, but no significant differences in |min1| or |FL-min1| ratios, between patients with and without thrombosis. CFWA monitoring of coagulation and fibrinolysis dynamics could provide valuable data for understanding hemostatic changes and disease status in COVID-19 patients.

Tocilizumab and Baricitinib for Recovery From Acute Exacerbation of Combined Pulmonary Fibrosis and Emphysema Secondary to COVID-19 Infection: A Case Report.

Pneumonia secondary to coronavirus disease 2019 (COVID-19) is exacerbated by a disproportionate increase in the systemic inflammatory response and cytokine storm due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Herein, we report the successful treatment of severe COVID-19 pneumonia using a combination of tocilizumab and baricitinib in a patient with combined pulmonary fibrosis and emphysema (CPFE). A 67-year-old male with type 2 diabetes mellitus and CPFE presented with fever and dyspnea and was diagnosed with COVID-19. Upon admission, his respiratory failure was managed using high-flow nasal cannula (HFNC) therapy; however, despite treatment with remdesivir and systemic steroids, his respiratory failure continued to worsen. Therefore, baricitinib was administered from the ninth day of hospitalization for 14 days. Furthermore, his blood interleukin-6 (IL-6) levels showed an increase until day 13. Thus, tocilizumab was administered on the 13th day, which led to symptomatic improvement by day 18. The patient was discharged from our hospital on day 42. This case indicates that combination therapy with tocilizumab and baricitinib improves the efficacy of COVID-19 treatment in patients with comorbidities.

Statement from the Japanese Respiratory Society: Working diagnosis and initial management of COPD during the COVID-19 pandemic.

The Japanese Respiratory Society (JRS) has recommended spirometry for the diagnosis of respiratory diseases. It is indispensable for the confirmation of airflow obstruction by spirometry in chronic obstructive pulmonary disease (COPD) diagnosis. However, the coronavirus disease 2019 (COVID-19) pandemic has made it difficult for many clinics to perform spirometry as it may lead to possible aerosol infections. Thus, the diagnosis of COPD, especially in the early stage, has become difficult. To overcome this situation, JRS issued a "Flowchart of Working Diagnosis and Management of COPD during the COVID-19 Pandemic". This flowchart may help physicians provisionally diagnose COPD patients without performing spirometry, offering them appropriate intervention even in epidemic and pandemic situations.