COVID-19 vaccine effectiveness against severe COVID-19 requiring oxygen therapy, invasive mechanical ventilation, and death in Japan: A multicenter case-control study (MOTIVATE study).

INTRODUCTION: Since the SARS-CoV-2 Omicron variant became dominant, assessing COVID-19 vaccine effectiveness (VE) against severe disease using hospitalization as an outcome became more challenging due to incidental infections via admission screening and variable admission criteria, resulting in a wide range of estimates. To address this, the World Health Organization (WHO) guidance recommends the use of outcomes that are more specific to severe pneumonia such as oxygen use and mechanical ventilation. METHODS: A case-control study was conducted in 24 hospitals in Japan for the Delta-dominant period (August-November 2021; "Delta") and early Omicron (BA.1/BA.2)-dominant period (January-June 2022; "Omicron"). Detailed chart review/interviews were conducted in January-May 2023. VE was measured using various outcomes including disease requiring oxygen therapy, disease requiring invasive mechanical ventilation (IMV), death, outcome restricting to "true" severe COVID-19 (where oxygen requirement is due to COVID-19 rather than another condition(s)), and progression from oxygen use to IMV or death among COVID-19 patients. RESULTS: The analysis included 2125 individuals with respiratory failure (1608 cases [75.7%]; 99.2% of vaccinees received mRNA vaccines). During Delta, 2 doses provided high protection for up to 6 months (oxygen requirement: 95.2% [95% CI:88.7-98.0%] [restricted to "true" severe COVID-19: 95.5% {89.3-98.1%}]; IMV: 99.6% [97.3-99.9%]; fatal: 98.6% [92.3-99.7%]). During Omicron, 3 doses provided high protection for up to 6 months (oxygen requirement: 85.5% [68.8-93.3%] ["true" severe COVID-19: 88.1% {73.6-94.7%}]; IMV: 97.9% [85.9-99.7%]; fatal: 99.6% [95.2-99.97]). There was a trend towards higher VE for more severe and specific outcomes. CONCLUSION: Multiple outcomes pointed towards high protection of 2 doses during Delta and 3 doses during Omicron. These results demonstrate the importance of using severe and specific outcomes to accurately measure VE against severe COVID-19, as recommended in WHO guidance in settings of intense transmission as seen during Omicron

CT-guided automated cutting needle biopsy by a combined method for accurate specific diagnosis of focal lung lesions

Purpose: The purpose of our study was to evaluate a method of automated cutting needle biopsy (ACNB) that combines the use of a long-throw needle, higher mean number of needle passes, and tandem system, in terms of the accuracy of specific diagnosis of small and large lung lesions and the safety of the procedure. Materials and Methods: Fifty-seven ACNBs were performed under computed tomography guidance using a tandem system with a 20-gauge and 18-gauge (through non-aerated lung) automated cutting needle with a throw length of 23 mm. We classified the nodules into 21 small nodules (≤2 cm) and 36 large nodules (>2 cm). All ACNB diagnoses were divided into three groups: specific, non-specific, and false diagnoses. All of the complications were recorded. Results: The mean number of ACNB specimens obtained was 2.0. Of the 35 ACNB procedures for malignant lesions, 33 yielded a specific malignant diagnosis (33/35, 94%). Of the 22 procedures for benign lesions, 17 gave a specific benign diagnosis (17/22, 77%). The diagnostic accuracy for small nodules was no lower than that for large nodules. Postbiopsy pneumothorax occurred in 18 patients (32%). Conclusion: The diagnostic accuracy of the combined method is as high for small lung nodules as for large ones. The procedure has high diagnostic accuracy for the subtypes of lung cancer and an acceptable complication rate.Link_to_subscribed_fulltex