Survey of the current status of subclinical coronavirus disease 2019 (COVID-19)
JOURNAL OF INFECTION AND CHEMOTHERAPY
Authors: Matsuba, Ikuro; Hatori, Nobuo; Koido, Norihiko; Watanabe, Yoshiyuki; Ebara, Futoshi; Matsuzawa, Yoko; Nishikawa, Tetsuo; Kunishima, Tomoyuki; Degawa, Hisakazu; Nishikawa, Masanori; Ono, Yoshiaki; Kanamori, Akira
Abstract
Objectives: We investigated relationships between subclinical COVID-19 (coronavirus disease 2019) and background factors. Methods: We determined SARS-CoV-2 antibody (IgG) prevalence in 1603 patients, doctors, and nurses in 65 medical institutions in Kanagawa Prefecture, Japan and investigated their background factors. Antibodies (IgG) against SARS-CoV-2 were analyzed by Immunochromatographic test. Results: The 39 subjects (2.4%) were found to be IgG antibody-positive: 29 in the patient group (2.9%), 10 in the doctor/nurse group (2.0%), and 0 in the control group. After adjustment for age, sex, and the antibody prevalence in the control group, antibody prevalence was 2.7% in the patient group and 2.1% in the doctor/nurse group. There was no significant difference between the antibody-positive subjects and the antibody-negative subjects in any background factors investigated including overseas travel, contact with overseas travelers, presence/absence of infected individuals in the living area, use of trains 5 times a week or more, BCG vaccination, and use of ACE inhibitor and ARB. Conclusions: Antibody prevalence in the present survey at medical institution is higher than that in Tokyo and in Osaka measured by the government suggesting that subclinical infections are occurring more frequently than expected. No background factor that influenced antibody-positive status due to subclinical infection was identified. (c) 2020 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
VaxiPatch (TM), a novel vaccination system comprised of subunit antigens, adjuvants and microneedle skin delivery: An application to influenza B/Colorado/06/2017
VACCINE
Authors: Ellison, Thomas J.; Talbott, George C.; Henderson, Daniel R.
Abstract
This work introduces VaxiPatch, a novel vaccination system comprised of subunit glycoprotein vaccine antigens, adjuvants and dermal delivery. For this study, rHA of influenza virus B/Colorado/06/2017 was incorporated into synthetic virosomes, and adjuvant liposomes were formed with QS-21 from Saponaria quillaja, with or without the synthetic TLR4 agonist 3D - (6-acyl) PHAD. These components were concentrated and co-formulated into trehalose with dye. Dermal delivery was achieved using an economical 37-point stainless steel microneedle array, designed for automated fill/finish by microfluidic dispensers used for mass production of immunodiagnostics. Vaccine and adjuvant are deposited to form a sugar glass in a pocket on the side of each of the tips, allowing skin penetration to be performed directly by the rigid steel structure. In this study, Sprague Dawley rats (n = 6 per group) were vaccinated by VaxiPatches containing 0.3 mu g of rHA, 0.5 mu g QS-21 and 0.2 mu g 3D - (6-acyl) PHAD and dye, resulting in antigen-specific IgG titers 100-fold higher than 4.5 mu g of FluBlok (p = 0.001) delivered intramuscularly. Similarly, hemagglutination inhibition titers in these animals were 14-fold higher than FluBlok controls (p = 0.01). Non-adjuvanted VaxiPatches were also compared with rHA virosomes injected intramuscularly. Accelerated shelf life studies further suggest that formulated virosomal antigens retain activity for at least two months at 60 degrees C. Further, co-formulation of a dye could provide a visible verification of delivery based on the temporary pattern on the skin. A room-temperature-stable vaccination kit such as VaxiPatch has the potential to increase vaccine use and compliance globally. (C) 2020 The Author(s). Published by Elsevier Ltd.