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Although vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease 2019 (COVID-19) induce effective immune responses, vaccination with booster doses is necessary because of waning immunity. We conducted an open-label, non-randomized, single-arm study in adults in Japan to assess the immunogenicity and safety of a single booster dose of the KD-414 purified whole-SARS-CoV-2-virion inactivated vaccine candidate after vaccination with a primary series of BNT162b2. The primary endpoint was serum neutralizing activity at 7 days after booster injection compared with the primary series of BNT162b2. The SARS-CoV-2-structural protein-binding antibody level and T cell response against SARS-CoV-2-Spike (S) peptides were also examined as secondary endpoints, and safety profile assessments were conducted. Twenty subjects who participated in a previous study declined an injection of KD-414 (non-KD-414 group) and received a booster dose of BNT162b2 instead. The non-KD-414 group was compared to the KD-414 group as a secondary outcome. A single dose of KD-414 induced lower serum neutralizing activity against the wild-type virus within 7 days compared to after the primary series of BNT162b2 but significantly induced anti-SARS-CoV-2-S1-receptor-binding domain-binding immunoglobulin G (IgG) antibodies and SARS-CoV-2-S peptide-specific CD4 + and CD8 + T cell responses. Local or systemic symptoms were significantly lower in the participants who received KD-414 than in those who received BNT162b2 as the third COVID-19 vaccine dose. The present data indicate that a single booster dose of KD-414 induces a substantial immune response in BNT162b2-primed individuals and has a good safety profile, thereby supporting further clinical trials to identify rational targets.

The aim of the study was to investigate the protective effect provided by immunization with commercial erysipelas vaccines in mice and conventional pigs to challenge with the field strains (serotype 1a) of Erysipelothrix rhusiopathiae. Sequence analysis of surface protective antigen (spaA) gene revealed that the strains were different from those reported previously. A total of 150 mice immunized subcutaneously with live or inactivated vaccines were protected against challenge exposure to one reference and four field strains. Seven conventional pigs immunized intramuscularly with inactivated vaccines developed specific antibodies against the SpaA protein of E. rhusiopathiae and were protected against challenge with two field strains. Our study is the first to demonstrate that the commercially available vaccines could protect animals against challenge with the most recently isolated SpaA-type strains of E. rhusiopathiae. [ABSTRACT FROM AUTHOR]

Asian sea bass, Lates calcarifer (Bloch), exhibited strong immune responses against a single injection of the formalin-inactivated red-spotted grouper nervous necrosis virus (RGNNV), a betanodavirus originally isolated in Japan. Fish produced neutralizing antibodies at high titre levels from days 10 (mean titre 1:480) to 116 (1:1280), with the highest titre at day 60 post-vaccination (1:4480). When fish were challenged with the homologous RGNNV at day 54 post-vaccination, there were no mortalities in both the vaccinated and unvaccinated control fish. However, a rapid clearance of the virus was observed in the brains and kidneys of vaccinated fish, followed by a significant increase in neutralizing-antibody titres. Furthermore, the vaccine-induced antibodies potently neutralized Philippine betanodavirus isolates (RGNNV) in a cross-neutralization assay. The present results indicate the potential of the formalin-inactivated RGNNV vaccine against viral nervous necrosis (VNN) of Asian seabass. [ABSTRACT FROM AUTHOR]

An inactivated equine influenza virus (EIV) vaccine and a live equine herpesvirus type 1 (EHV-1) vaccine are usually administered concurrently to Thoroughbred racehorses in Japan. The objective of this study was to evaluate whether concurrent administration of an inactivated EIV vaccine and a live EHV-1 vaccine in Thoroughbred racehorses influences the antibody response against EIV. We compared the antibody response against EIV in horses administered both vaccines on the same day (Group A; n = 27) and the response in horses administered an inactivated EIV vaccine first and then a live EHV-1 vaccine 1-2 weeks later (Group B; n = 20). In both groups, geometric mean hemagglutination inhibition (HI) titers against A/equine/Ibaraki/1/2007 and A/equine/Yokohama/aq13/2010 increased significantly after EIV vaccination. However, the percentage of horses that showed a twofold increase or greater in HI titers against A/equine/Yokohama/aq13/2010 was significantly higher in Group B (75%) than in Group A (37%; P = .02). These results suggest that the concurrent use of an inactivated EIV vaccine and a live EHV-1 vaccine reduced the immune response against EIV to some extent, and it would be better to use these vaccines consecutively, especially for naïve horses or horses whose vaccination history is incomplete., (Copyright © 2020. Published by Elsevier Inc.)

Background: Adjuvants used in inactivated vaccines often upregulate type 2 immunity, which is dominant in allergic diseases. We hypothesised that cumulative adjuvant exposure in infancy may influence the development of allergies later in life by changing the balance of type 1/type 2 immunity. We examined the relationship between immunisation with different vaccine types and later allergic disease development., Methods: We obtained information regarding vaccinations and allergic diseases through questionnaires that were used in The Japan Environment and Children's Study (JECS), which is a nationwide, multicentre, prospective birth cohort study that included 103,099 pregnant women and their children. We examined potential associations between the initial vaccination before 6 months of age and symptoms related to allergies at 12 months of age., Results: Our statistical analyses included 56,277 children. Physician-diagnosed asthma was associated with receiving three (aOR 1.395, 95% CI 1.028-1.893) or four to five different inactivated vaccines (aOR 1.544, 95% CI 1.149-2.075), compared with children who received only one inactivated vaccine. Similar results were found for two questionnaire-based symptoms, i.e. wheeze (aOR 1.238, 95% CI 1.094-1.401; three vaccines vs. a single vaccine) and eczema (aOR 1.144, 95% CI 1.007-1.299; four or five vaccines vs. a single vaccine)., Conclusions: Our results, which should be cautiously interpreted, suggest that the prevalence of asthma, wheeze and eczema among children at 12 months of age might be related to the amount of inactivated vaccine exposure before 6 months of age. Future work should assess if this association is due to cumulative adjuvant exposure. Despite this possible association, we strongly support the global vaccination strategy and recommend that immunisations continue., Trial Registration: UMIN000030786 .

Background: Equine herpesvirus type 1 (EHV-1) infection is a major cause of pyrexias in winter among Japanese racehorses. In 2014-2015, the Japan Racing Association (JRA) changed the EHV-1 vaccine from an inactivated vaccine to a live vaccine (both produced by Nisseiken). To evaluate the effect of changing the vaccines, the capacities of these vaccines to induce virus-neutralizing (VN) antibodies were compared, and an epizootiological investigation of EHV-1 was performed at the JRA Ritto Training Center during epizootic periods from 2010-2011 to 2016-2017., Results: Three-year-old horses that received the first dose of live vaccine showed higher geometric mean (GM) VN titers (205 and 220) than those that received inactivated vaccine (83, P < 0.05). The response rates after vaccination with the live vaccine (76 and 90%) were higher than that after vaccination with inactivated vaccine (42%, P < 0.05). Four-year-old horses from 2015 to 2017 that had received the live vaccine in the previous epizootic periods had higher GM titers (205 to 246) than those from 2011 to 2014, which had received the inactivated vaccine (139 to 164, P < 0.05). The estimated numbers of horses infected with EHV-1 or EHV-4, or both, in 2011-2012 (29 [95%CI: 21-37]) and 2013-2014 (37 [95%CI: 27-47]) were higher than those in the other periods (7 [95%CI: 2-12] to 16 [95%CI: 9-23]). Likewise, the seroconversion rates to EHV-1 in horses that stayed at the training center in 2011-2012 (66.0%) and 2013-2014 (52.0%) were higher than those in the other periods (12.0 to 28.6%)., Conclusions: The live EHV-1 vaccine is highly immunogenic and provides greater VN antibody responses than the inactivated vaccine. Unlike the period when the policy was to use inactivated vaccine, there was no detectable epizootic EHV-1 infection at the training center during three consecutive periods after the introduction of the live vaccine. These results suggest that the replacement of inactivated vaccine with live vaccine, together with the achievement of high vaccination coverage, reinforced the herd effect, and contributed to better control of EHV-1 epizootics in the training center.