著者

Yoko Takayama Toshiaki Komatsu Tatsuhiko Wada Shin Nihonyanagi Takayuki Hoshiyama Tatsumi Moriya Shizue Shimamura Naoko Kajigaya Masanori Naito Osamu Takeuchi Yuki Bando Masahiko Watanabe Masatsugu Iwamura Hideaki Hanaki

出版者

The Medical Association of Nippon Medical School

雑誌

Journal of Nippon Medical School (ISSN:13454676)

巻号頁・発行日

vol.89, no.5, pp.513-519, 2022-10-25 (Released:2022-11-09)

参考文献数

33

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Background: Antibody testing is essential for accurately estimating the number of people infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This study aimed to investigate the influence of background factors on seroprevalence by testing for anti-SARS-CoV-2 antibodies in blood samples obtained from the staff of three hospitals. Methods: This cross-sectional observational study was conducted from June 8 to July 4, 2020, as part of a mandatory health examination. Leftover blood samples collected during the health examinations at each hospital were used to test for the presence of anti-SARS-CoV-2 antibodies. The Elecsys Anti-SARS-CoV-2 RUO assay was used for antibody detection. The relationship between staff age, gender, body mass index, blood pressure, work environments with different exposure risks, place of residence, and campus location and seroprevalence was investigated. The data were anonymized prior to analysis. Results: A total of 3,677 individuals were included in the study, comprising 2,554 females (69.5%) and 1,123 males (30.5%). Anti-SARS-CoV-2 antibody (immunoglobulin G) was detected in 13 participants (0.35%). Seroprevalence was slightly higher in males than females (0.62% vs. 0.23%, P=0.08). By occupation, anti-SARS-CoV-2 antibodies were found in 6 (0.75%) physicians, 6 (0.31%) nurses, and one individual (0.11%) in the medical personnel group, with slightly higher levels in physicians. No significant difference was noted in the seroprevalence in terms of all background factors. Conclusions: Our study shows that the background factors do not impact seropositivity rates. Thorough daily infection control and adherence to recommended health guidelines were found to reduce infection risk.

著者

Takayuki Hoshiyama Tatsuhiko Wada Shin Nihonyanagi Ryo Kameda Minako Yamaoka-Tojo Michinari Fukuda Jyunya Ako Kunihiro Yamaoka Yoko Takayama

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

pp.5601-20, (Released:2020-11-02)

参考文献数

42

被引用文献数

6

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Objective To describe the clinical features and clinical course of individuals diagnosed with asymptomatic SARS-CoV-2 infection or mild COVID-19. Patients The study participants consisted of 7 crewmembers of the passenger cruise-liner, Diamond Princess, who were admitted to our hospital after becoming infected with SARS-CoV-2 aboard the ship. Methods The data on patient background and biochemical test results were obtained from the patients' medical records. All patients had a chest X-ray, and a throat swab and sputum samples were sent for culture on admission. Results The median age of the 7 patients, of whom 4 were male and 3 were female, was 39 years (range: 23-47 years). On admission, none of them had fever, but 4 (57%) had a cough. None of them showed any signs of organ damage on laboratory testing. Chest X-ray showed pneumonia in one individual, which resolved spontaneously, while the other 6 had normal chest X-ray findings. Culture of throat swabs and sputum samples revealed that 4 patients (57%) had bacterial upper respiratory infections (Haemophilus influenzae, Klebsiella pneumoniae, and Staphylococcus aureus). The period from a positive PCR test to negative conversion ranged from 5 to 13 days, with a median of 8 days. Conclusion Healthy young adults without risk factors who acquire SARS-CoV-2 infection may have an asymptomatic infection or may experience mild COVID-19. In addition to obesity, an older age, underlying illness, and being overweight can lead to a risk of exacerbation; thus, hospital management for such individuals may be desirable. Culturing respiratory samples may be useful for diagnosing secondary bacterial pneumonia.