Effectiveness of mRNA COVID-19 vaccines against symptomatic SARS-CoV-2 infections during the SARS-CoV-2 Omicron BA.1 and BA.2 epidemic in Japan: vaccine effectiveness real-time surveillance for SARS-CoV-2 (VERSUS).

BACKGROUND: Evaluating COVID-19 vaccine effectiveness (VE) domestically is crucial for assessing and determining national vaccination policy. This study aimed to evaluate VE of mRNA COVID-19 vaccines in Japan. METHODS: We conducted a multicenter test-negative case-control study. The study comprised individuals aged ≥16 visiting medical facilities with COVID-19-related signs or symptoms from 1 January to 26 June 2022, when Omicron BA.1 and BA.2 were dominant nationwide. We evaluated VE of primary and booster vaccination against symptomatic SARS-CoV-2 infections and relative VE of booster compared with primary. RESULTS: We enrolled 7,931 episodes, including 3,055 test positive. The median age was 39, 48.0% were male, and 20.5% had underlying medical conditions. In individuals aged 16 to 64, VE of primary vaccination within 90 days was 35.6% (95% CI, 19.0-48.8%). After booster, VE increased to 68.7% (60.6-75.1%). In individuals aged ≥65, VE of primary and booster was 31.2% (-44.0-67.1%) and 76.5% (46.7-89.7%), respectively. Relative VE of booster compared with primary vaccination was 52.9% (41.0-62.5%) in individuals aged 16 to 64 and 65.9% (35.7-81.9%) in individuals aged ≥65. CONCLUSIONS: During BA.1 and BA.2 epidemic in Japan, mRNA COVID-19 primary vaccination provided modest protection. Booster vaccination was necessary to protect against symptomatic infections.

Effectiveness of Messenger RNA Coronavirus Disease 2019 Vaccines Against Symptomatic Severe Acute Respiratory Syndrome Coronavirus 2 Infections During the Delta Variant Epidemic in Japan: Vaccine Effectiveness Real-time Surveillance for SARS-CoV-2 (VERSUS).

BACKGROUND: Although high vaccine effectiveness of messenger RNA (mRNA) coronavirus disease 2019 (COVID-19) vaccines has been reported in studies in several countries, data are limited from Asian countries, especially against the Delta (B.1.617.2) variant. METHODS: We conducted a multicenter test-negative case-control study in patients aged ≥16 years visiting hospitals or clinics with signs or symptoms consistent with COVID-19 from 1 July to 30 September 2021, when the Delta variant was dominant (≥90% of SARS-CoV-2 infections) nationwide in Japan. Vaccine effectiveness of BNT162b2 or mRNA-1273 against symptomatic SARS-CoV-2 infections was evaluated. Waning immunity among patients aged 16-64 years was also assessed. RESULTS: We enrolled 1936 patients, including 396 test-positive cases and 1540 test-negative controls for SARS-CoV-2. The median age was 49 years, 53.4% were male, and 34.0% had underlying medical conditions. Full vaccination (receiving 2 doses ≥14 days before symptom onset) was received by 6.6% of cases and 38.8% of controls. Vaccine effectiveness of full vaccination against symptomatic SARS-CoV-2 infections was 88.7% (95% confidence interval [CI], 78.8%-93.9%) among patients aged 16-64 years and 90.3% (95% CI, 73.6%-96.4%) among patients aged ≥65 years. Among patients aged 16-64 years, vaccine effectiveness was 91.8% (95% CI, 80.3%-96.6%) within 1-3 months after full vaccination, and 86.4% (95% CI, 56.9%-95.7%) within 4-6 months. CONCLUSIONS: mRNA COVID-19 vaccines had high effectiveness against symptomatic SARS-CoV-2 infections in Japan during July-September 2021, when the Delta variant was dominant nationwide.

Impaired Consciousness in a Coronavirus Disease 2019 Patient Caused by Low Serum Sodium: A Case Report.

A 30 year-old man with a high fever (37.5°C-40°C), vomiting, slurred speech, and mild cognitive impairment was admitted to our Emergency Department. He had traveled from Spain to the UK on business at the end of February 2020. A nasopharyngeal swab was positive by RT-PCR for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but a cerebrospinal fluid (CSF) sample was negative. His neurological abnormalities recovered completely on saline infusion to normalize his low serum sodium level. Although neurological abnormalities in patients with COVID-19 are rare, it is important to distinguish the etiologies including encephalitis, meningitis, or merely electrolyte abnormalities.

Evaluation of Surgical Instruments With Radiofrequency Identification Tags in the Operating Room.

BACKGROUND: Surgical instrument retention and instrument breakage compromise surgery quality and lead to medical malpractice. We developed an instrument tracking system that could alert surgeons to instrument retention during surgery and monitor instrument use to reduce the risk of breakage. METHODS: This prospective, experimental clinical trial included 15 patients undergoing inguinal hernia surgery or lumpectomy under general anesthesia at Saiseikai Kurihashi Hospital. Radiofrequency identification (RFID)-tagged surgical instruments were used, and a detection antenna was placed on a mayo stand during the operation. We analyzed the 1-loop detection ratio (OLDR)-that is, the capability of the antenna to detect devices in a single reading-and the total detection rate (TDR)-that is, the data accumulated for the duration of the operation-of the RFID-tagged instruments. RESULTS: Data analysis revealed that the OLDR was 95% accurate, whereas the TDR was 100% accurate. The antenna could not detect the RFID tag when there was interference from electrocautery noise radiation, and 6% of instrument movement was undetected by the antenna; however, the TDR and instrument use were detected at all times. CONCLUSIONS: Surgical instruments can be tracked during surgery, and this tracking can clarify the usage rate of each instrument and serve as a backup method of instrument counting. However, this study was conducted on a small scale, and RFID tags cannot be attached to small surgical instruments used in complex operations such as neurosurgery. Further efforts to develop a tracking system for these instruments are warranted.

Management of surgical instruments with radio frequency identification tags.

PURPOSE: To prevent malpractices, medical staff has adopted inventory time-outs and/or checklists. Accurate inventory and maintenance of surgical instruments decreases the risk of operating room miscounting and malfunction. In our previous study, an individual management of surgical instruments was accomplished using Radio Frequency Identification (RFID) tags. The purpose of this paper is to evaluate a new management method of RFID-tagged instruments. DESIGN/METHODOLOGY/APPROACH: The management system of RFID-tagged surgical instruments was used for 27 months in clinical areas. In total, 13 study participants assembled surgical trays in the central sterile supply department. FINDINGS: While using the management system, trays were assembled 94 times. During this period, no assembly errors occurred. An instrument malfunction had occurred after the 19th, 56th, and 73 th uses, no malfunction caused by the RFID tags, and usage history had been recorded. Additionally, the time it took to assemble surgical trays was recorded, and the long-term usability of the management system was evaluated. ORIGINALITY/VALUE: The system could record the number of uses and the defective history of each surgical instrument. In addition, the history of the frequency of instruments being transferred from one tray to another was recorded. The results suggest that our system can be used to manage instruments safely. Additionally, the management system was acquired of the learning effect and the usability on daily maintenance. This finding suggests that the management system examined here ensures surgical instrument and tray assembly quality.

Validation of cleaning evaluation of surgical instruments with RFID tags attached based on cleaning appraisal judgment guidelines.

In medical institutions, the threat of infection is closely focused, in particular, inspections regarding surgical site infections (SSI) are carried out. In this study, development of the application of Radio frequency identification (RFID) tags for surgical instrument has been promoted. It enables traceability and individual management of surgical instruments. An experiment was carried out following the cleaning Appraisal guidelines, which contaminated surgical instruments, and using the washer-disinfector (WD) as the main cleaner for surgical instruments with developed RFID tags attached to them. As a result, all of the instruments with RFID tags, the amount of residual protein was less than the recommended acceptable level of 100µg. If WD is used correctly, a sufficient cleaning effect can be expected. From this result, it became evident that the secondary infection risk is low from surgical instrument with RFID tags attached.