著者

Masahiro Ishikane Yusuke Miyazato Satoshi Kustuna Tetsuya Suzuki Satoshi Ide Keiji Nakamura Shinichiro Morioka Harutaka Katano Tadaki Suzuki Norio Ohmagari

出版者

National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee

雑誌

Japanese Journal of Infectious Diseases (ISSN:13446304)

巻号頁・発行日

pp.JJID.2020.240, (Released:2020-05-29)

参考文献数

14

被引用文献数

1

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We report a case of patient in Japan with Coronavirus disease 2019 (COVID-19) with false-negative of reverse transcription polymerase chain reaction for Severe Acute Respiratory Syndrome Coronavirus 2 of pharyngeal swab, from a Chinese traveller returning from Wuhan, Hubei Province, China. If a patient is clinically or epidemiologically suspected of COVID-19, appropriate infection and prevention control measures such as standard, contact, and droplet precaution are needed until the patient is proven to be true-negative.

著者

Kango TATEMOTO Keita ISHIJIMA Yudai KURODA Milagros Virhuez MENDOZA Yusuke INOUE Eunsil PARK Hiroshi SHIMODA Yuko SATO Tadaki SUZUKI Kazuo SUZUKI Shigeru MORIKAWA Ken MAEDA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.22-0236, (Released:2022-05-31)

被引用文献数

7

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The present study investigated severe fever with thrombocytopenia syndrome virus (SFTSV) infection in raccoons in Wakayama Prefecture from 2007 to 2019. To perform surveillance, an enzyme-linked immunosorbent assay (ELISA) was established, and the sensitivity and specificity of the ELISA were 100% in comparison with a 50% focus-reduction neutralization assay. Using the established ELISA, we performed serosurveillance of SFTSV infection in 2,299 raccoons in Tanabe region, Wakayama Prefecture from 2007 to 2019. The first anti-SFTSV-positive raccoon was captured in October 2009. The seroprevalence of SFTSV infection was <10% between April 2009 and March 2013, 23.9% between April 2013 and March 2014, 37.5% between April, 2014 and March 2015, and over 50% from April 2015. Next, we performed detection of SFTSV genes in sera of raccoons captured in Wakayama Prefecture after April 2013. The results indicated that 2.4% of raccoons were positive for SFTSV genes and that the frequency of SFTSV infection among raccoons between January and March (0.7%) was lower than that between April and June (3.4%). In addition, virus genes were detected from many specimens, including sera and feces of two raccoons, and viral antigens were detected in lymphoid cells in lymphoid follicles in the colon by immunohistochemical staining. In conclusion, SFTSV had recently invaded the area and had rapidly spread among wild animals. The first patient in this area was reported in June 2014, indicating that raccoons are good sentinels for assessing the risk of SFTSV in humans.

著者

Yuta Chiba Rie Kawakita Katsuya Mitamura Kenta Takahashi Tadaki Suzuki Kazuo Nakamichi Kenta Suzuki Asahiro Morishita Hideki Kobara Kazushi Deguchi Tsutomu Masaki

出版者

The Japanese Society of Internal Medicine

雑誌

Internal Medicine (ISSN:09182918)

巻号頁・発行日

pp.3023-23, (Released:2024-01-02)

参考文献数

12

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An 84-year-old Japanese woman presented with left hemiplegia 8 months after completing chemotherapy for mantle cell lymphoma. Brain magnetic resonance imaging (MRI) revealed a hyperintense lesion extending from the right parietal lobe to the left parietal lobe. Compared with these MRI results, 18F-THK5351 PET revealed more extensive accumulation. A brain biopsy showed progressive multifocal leukoencephalopathy (PML). Immunohistochemistry and John Cunningham virus (JCV) DNA-polymerase chain reaction indicated JCV infection. Therefore, a diagnosis of PML was made. 18F-THK5351 PET, indicative of activated astrocytes, clearly depicted PML lesions composed of reactive and atypical astrocytes. 18F-THK5351 PET may capture fresh progressive PML lesions better than MRI.

著者

Yuki Higashimoto Masaru Ihira Yoshiki Kawamura Masato Inaba Kazuya Shirato Tadaki Suzuki Hideki Hasegawa Tsutomu Kageyama Yohei Doi Tadayoshi Hata Tetsushi Yoshikawa

出版者

Fujita Medical Society

雑誌

Fujita Medical Journal (ISSN:21897247)

巻号頁・発行日

pp.2022-003, (Released:2022-07-22)

参考文献数

38

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Objectives: To establish a point-of-care test for coronavirus disease 2019 (COVID-19), we developed a dry loop-mediated isothermal amplification (LAMP) method to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA.Methods: We carried out reverse transcription (RT)-LAMP using the Loopamp SARS-CoV-2 Detection kit (Eiken Chemical, Tokyo, Japan). The entire mixture, except for the primers, is dried and immobilized inside the tube lid.Results: To determine the specificity of the kit, 22 viruses associated with respiratory infections, including SARS-CoV-2, were tested. The sensitivity of this assay, determined by either a real-time turbidity assay or colorimetric change of the reaction mixture, as evaluated by the naked eye or under illumination with ultraviolet light, was 10 copies/reaction. No LAMP product was detected in reactions performed with RNA from any pathogens other than SARS-CoV-2. After completing an initial validation analysis, we analyzed 24 nasopharyngeal swab specimens collected from patients suspected to have COVID-19. Of the 24 samples, 19 (79.2%) were determined by real-time RT-PCR analysis as being positive for SARS-CoV-2 RNA. Using the Loopamp SARS-CoV-2 Detection kit, we detected SARS-CoV-2 RNA in 15 (62.5%) of the 24 samples. Thus, the sensitivity, specificity, positive predictive value, and negative predictive values of the Loopamp 2019-CoV-2 detection reagent kit were 78.9%, 100%, 100%, and 55.6%, respectively.Conclusions: The dry LAMP method for detecting SARS-CoV-2 RNA is fast and easy to use, and its reagents can be stored at 4°C, solving the cold chain problem; thus, it represents a promising tool for COVID-19 diagnosis in developing countries.

著者

Shin-ichi Tamura Akira Ainai Tadaki Suzuki Takeshi Kurata Hideki Hasegawa

出版者

National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee

雑誌

Japanese Journal of Infectious Diseases (ISSN:13446304)

巻号頁・発行日

vol.69, no.3, pp.165-179, 2016 (Released:2016-05-20)

参考文献数

98

被引用文献数

23 33

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Influenza is a contagious, acute respiratory disease caused by the influenza virus. The mucosal lining in the host respiratory tract is not only the site of virus infection, but also the site of defense; it is at this site that the host immune response targets the virus and protects against reinfection. One of the most effective methods to prevent influenza is to induce specific antibody (Ab) responses in the respiratory tract by vaccination. Two types of influenza vaccines, intranasal live attenuated influenza virus (LAIV) vaccines and parenteral (injectable) inactivated vaccines, are currently used worldwide. These vaccines are approved by the European Medicines Agency (EMA) and the US Food and Drug Administration. Live attenuated vaccines induce both secretory IgA (S-IgA) and serum IgG antibodies (Abs), whereas parenteral vaccines induce only serum IgG Abs. However, intranasal administration of inactivated vaccines together with an appropriate adjuvant induces both S-IgA and IgG Abs. Several preclinical studies on adjuvant-combined, nasal-inactivated vaccines revealed that nasal S-IgA Abs, a major immune component in the upper respiratory tract, reacted with homologous virus hemagglutinin (HA) and were highly cross-reactive with viral HA variants, resulting in protection and cross-protection against infection by both homologous and variant viruses, respectively. Serum-derived IgG Abs, which are present mainly in the lower respiratory tract, are less cross-reactive and cross-protective. In addition, our own clinical trials have shown that nasal-inactivated whole virus vaccines, including a built-in adjuvant (single-stranded RNA), induced serum hemagglutination inhibition (HI) Ab titers that fulfilled the EMA criteria for vaccine efficacy. The nasal-inactivated whole virus vaccines also induced high levels of nasal HI and neutralizing Ab titers, although we have not yet evaluated the nasal HI titers due to the lack of official criteria to establish efficacy based on this parameter. Data suggest that adjuvant-combined nasal-inactivated vaccines have advantages over the current injectable vaccine because the former induce both S-IgA and serum IgG Abs. In addition, nasal-inactivated vaccines seem to be superior to the LAIV vaccines, because non-infectious preparations could be used in high-risk groups. Thus, the development of intranasal inactivated vaccines is recommended, because such vaccines are expected to improve the efficacy of influenza vaccines.

著者

Kiyoko Okamaoto Kazuya Shirato NagaNaganori Nao Shinji Saito Tsutomu Kageyama Hideki Hasegawa Tadaki Suzuki Shutoku Matsuyama Makoto Takeda

出版者

National Institute of Infectious Diseases, Japanese Journal of Infectious Diseases Editorial Committee

雑誌

Japanese Journal of Infectious Diseases (ISSN:13446304)

巻号頁・発行日

pp.JJID.2020.108, (Released:2020-04-30)

参考文献数

11

被引用文献数

13 33

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The COVID-19 outbreak caused by SARS-CoV-2 in Wuhan (China) in December 2019 is currently spreading rapidly and globally. We recently reported a laboratory diagnostic protocol for SARS-CoV-2 based on real-time RT-PCR assays using two primer sets, N and N2. On 30–31 January 2020, the protocol and reagents for these assays were distributed to local public health institutes and quarantine depots in Japan, and nationwide, SARS-CoV-2 diagnostic testing was started. For further validation, the assays were compared with the commercially available kits using SARS CoV-2 viral RNA and the clinical specimens obtained from COVID19-suspected individuals. The LightMix Modular SARS and Wuhan CoV E-gene (LN S&W-E) assay was highly sensitive for SARS-CoV-2, as was the N2 set, and both assays had perfectly consistent results with the clinical specimens. While the LM S&W-E set targets the highly conserved region of the E gene in SARS-CoV and SARS-CoV-2, the N2 set was designed to target the unique region in the SARS-CoV-2 N gene. Thus, the N2 set has high specificity and sensitivity for SARS-CoV-2 detection. These indicate that the protocol using the N and N2 sets is comparable to commercially available kits and is reliable for the laboratory diagnosis of COVID-19.