• IMMUNE NETWORK
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• v.23 no.6
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• pp.47.1-47.16
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• 2023

Scrub typhus, a mite-borne infectious disease, is caused by Orientia tsutsugamushi. Despite many attempts to develop a protective strategy, an effective preventive vaccine has not been developed. The identification of appropriate Ags that cover diverse antigenic strains and provide long-lasting immunity is a fundamental challenge in the development of a scrub typhus vaccine. We investigated whether this limitation could be overcome by harnessing the nanoparticle-forming polysorbitol transporter (PST) for an O. tsutsugamushi vaccine strategy. Two target proteins, 56-kDa type-specific Ag (TSA56) and surface cell Ag A (ScaA) were used as vaccine candidates. PST formed stable nano-size complexes with TSA56 (TSA56-PST) and ScaA (ScaA-PST); neither exhibited cytotoxicity. The formation of Ag-specific IgG2a, IgG2b, and IgA in mice was enhanced by intranasal vaccination with TSA56-PST or ScaA-PST. The vaccines containing PST induced Ag-specific proliferation of CD8⁺ and CD4⁺ T cells. Furthermore, the vaccines containing PST improved the mouse survival against O. tsutsugamushi infection. Collectively, the present study indicated that PST could enhance both Ag-specific humoral immunity and T cell response, which are essential to effectively confer protective immunity against O. tsutsugamushi infection. These findings suggest that PST has potential for use in an intranasal vaccination strategy.

• Health Policy and Management
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• v.25 no.2
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• pp.140-148
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• 2015

Vaccination is the most powerful and useful preparation against infectious diseases. However, developing vaccines costs a lot and requires extensive long-term efforts. Therefore, the government should research and develop vaccines with a national-level policy. To greatly enhance the success rate of vaccine development, the policy should be set up considering priorities such as the current status of domestic research, the importance for public health, the urgency of research. The Delphi technique was utilized to draft this survey, through a brainstorming stage, then two inquiries, and finally the final panel meeting where unresolved items were discussed, to draw the conclusion. Among the results, firstly, the highest ranked item on centralized fields for vaccine development by the Ministry of Health was 'self-sufficiency of vaccines.' Secondly, 'emerging infectious disease' was most highly ranked in prioritized fields of vaccine development and research. Thirdly, for the vaccine that needs to be improved and developed further by the government to improve its efficacy and safety, BCG (Bacille de Calmette) for tuberculosis was ranked the highest on both types (intradermal and subcutaneous injection) from National Immunization Programme (NIP) and non-NIP. As for the high risk pathogens, 'anthrax' and 'smallpox' were first and second, consecutively. Lastly, 'development and control of vaccine candidates' was ranked the highest for the area in need for technique development in order to improve domestic vaccine's research level. The results of this study will be put to good use as basic data for the national vaccine research and development (R&D) policy of the country. This study was first step and more studies should be carried out for the final decision of the national vaccine R&D priority.

• Journal of Yeungnam Medical Science
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• v.29 no.1
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• pp.1-8
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• 2012

Streptococcus pneumonia is a very important pathogen for children and elderly people. Two types of pneumococcal vaccines are available in the market: pneumococcal polysaccharide vaccine (PPSV) and pneumococcal conjugate vaccine (PCV). PPSVs have been used for more than 30 years, and PCVs for about 10 years. There have been many reports concerning the evaluation of the vaccines' efficacies in preventing pneumococcal diseases such as meningitis, pneumonia, and otitis media and bacteremia, but the clinical trials had been performed with different conditions, such as diverse vaccine valencies, age groups, races, target outcomes, immunological cut-off values, and follow-up periods. PPSV is recommended for elderly people and chronic disease patients such as asthma, diabetes mellitus, chronic renal failure, and hyposplenic patients. According to the data from several systemic reviews and population-based surveillances, PPSV is effective for pneumococcal pneumonia and vaccine-type bacteremia among healthy adults. Until now, however, there is insufficient evidence of the effectiveness of PPSV among high-risk adults. PCV is very effective in preventing vaccine-type invasive pneumococcal disease (IPD) among children, but its efficacy for pneumonia is very low among children. The incidence of vaccine-related or non-vaccine-type IPDs is increasing after the introduction of 7-valent PCV (PCV7) as a routine immunization for children. Recently, 10- and 13-valent PCVs have been used for children, instead of PCV7. Therefore, continuous surveillance for serotype change among pneumococcal diseases is necessary to evaluate the vaccines' efficacy.

• Clinical and Experimental Vaccine Research
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• v.12 no.3
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• pp.193-208
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• 2023

One of the most significant medical advancements in human history is the development of vaccines. Progress in vaccine development has always been greatly influenced by scientific human innovation. The main objective of vaccine development would be to acquire sufficient evidence of vaccine effectiveness, immunogenicity, safety, and/or quality to support requests for marketing approval. Vaccines are biological products that enhance the body's defenses against infectious diseases. From the first smallpox vaccine to the latest notable coronavirus disease 2019 nasal vaccine, India has come a long way. The development of numerous vaccines, driven by scientific innovation and advancement, combined with researcher's knowledge, has helped to reduce the global burden of disease and mortality rates. The Drugs and Cosmetics Rules of 1945 and the New Drugs and Clinical Trials Rules of 2019 specify the requirements and guidelines for CMC (chemistry, manufacturing, and controls) for all manufactured and imported vaccines, including those against coronavirus infections. This article provides an overview of the regulation pertaining to the development process, registration, and approval procedures for vaccines, particularly in India, along with their brief history.

• Clinical and Experimental Vaccine Research
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• v.12 no.3
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• pp.209-215
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• 2023

Purpose: The delay in acceptance or refusal to get vaccinated despite the availability of services is called vaccine hesitancy. The Global Polio Eradication Initiative in Pakistan faced consistent barriers preventing the eradication of the disease in the country. Similarly with the advent of the coronavirus disease 2019 (COVID-19) pandemic mass vaccination drives were initiated to a vaccine hesitant population. The aim of this study is to explore the prevalence and reasons for COVID-19 vaccine hesitancy in the Pakistani population. Materials and Methods: Cross-sectional study conducted during July to September 2021 using a snowball sampling technique targeting the adult population of Pakistan. The modified version of the vaccine hesitancy questionnaire related to the Strategic Advisory Group of Experts on Immunization Vaccine Hesitancy matrix was distributed online. Results: Out of 973 participants, 52.4% were immediately willing to take the vaccine and constituted the acceptance group whereas the remaining 47.6% who were still not sure formed the hesitant group. Support from leaders was found to be statistically significant for the difference between the hesitant and acceptance groups (p-value=0.027). Hesitant people were concerned about the effectiveness of the vaccine (60.9%) and potential side effects (57.9%) as it was not sufficiently tested prior to launch (44.7%). Age and education were significant factors affecting the acceptance of vaccination. The most trusted source of information regarding vaccination was health care workers (43.8%). Conclusion: A moderately high prevalence of vaccine hesitancy was reported in Pakistan. To overcome it, policymakers need to address the reasons for it. Leaders, celebrities, and healthcare workers can play an instrumental role in dispelling conspiracy theories regarding vaccines and making the vaccination drive a success.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.53-60
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• 2008

We have investigated efficiency of a recombinant subunit Pasteurella multocida toxin (PMT) that was mixed with a vaccine consisted of inactivated whole cells of Bordetella bronchiseptica, P. multocida (types A and D). For verification of the efficacy of the vaccine, all experimental pigs (suckling piglets, sow and gilts) in the three farms were vaccinated. Antibody titers against B. bronchiseptica and P. multocida type A of the vaccinated pigs by microplate agglutination were significantly higher than those of the control pigs (p < 0.05). Similar patterns were observed in the analysis of anti- PMT neutralizing antibody by serum neutralizing method using Vero cell (p < 0.05). Anti- P. multocida type D antibody titer of the vaccinated sows and gilts by ELISA showed significant differences with those of the non-vaccinated pigs (p < 0.05). Although antibody titers increased, it was unable to find out the difference in the clinical signs between the vaccinated and non-vaccinated pigs. However, the increase in body weight of the vaccinated piglets was observed in comparison with the non-vaccinated piglets on a farm. At slaughtering of the pigs, pathological lesions in the turbinate bones of the vaccinated pigs were significantly lower than those of the non-vaccinated pigs (p < 0.001). These results suggested that efficacy of the vaccine in pigs demonstrated to protect against atrophic rhinitis in Korea.

• Journal of Preventive Medicine and Public Health
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• v.41 no.3
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• pp.153-158
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• 2008

Objectives : This study describes a plan that was designed to prevent a measles outbreak that showed a changed outbreak pattern. This study is based on the epidemiological investigation of a measles outbreak in a preschool in Incheon, Korea, 2006. Methods : The subjects were 152 students at a preschool where a measles outbreak occurred. A questionnaire survey was conducted and serological testing for measles-specific IgM was preformed. Results : Of the fifteen confirmed, identified cases, eleven patients had been vaccinated with one dose, one patient had received two doses and three patients were unvaccinated. The three unvaccinated cases consisted of one 5-year-old child, one 3-year-old child and one 16-month-old infant. For the cases with one dose of the vaccination, there were 11 cases, which consisted of six 5-year-old children, two 4-year-old children, two 3-year-old children and one 2-year-old child. The case with two doses of the vaccination was one 4-year-old child. The attack rate of measles was 100% in the 0-dose group, 11.2% in the 1-dose group and 2.0% in the 2-dose group. The vaccine's efficacy was 88.8% in the 1-dose group and 98.0% in the 2-dose group. The vaccine effectiveness for the 2-dose group was higher than that of the 1-dose group. Conclusions : High coverage with a 2-dose vaccination should be maintained, and the vaccination should be given at the suitable time to prevent a measles outbreak with a changed outbreak pattern.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.4
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• pp.634-639
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• 2020

Objective: This study was conducted to investigate the effect of heating of foot-and-mouth disease (FMD) vaccine before injection, on the incidence of lesions at the injection site (pork butt), amount of discarded meat, and economical benefit. Methods: In total, 101,086 piglets raised in 30 farms, were vaccinated in the neck with 2 mL of FMD vaccine at 56 d and 84 d of age using a commercial syringe. The heat treatment group (48,511 pigs) was injected with the FMD vaccine after it had been heated in a water bath at 40℃ for 20 min. After slaughter, the incidence of lesions on the pork butt was inspected, and the subsequent amount of discarded meat was recorded. Results: Heat treatment of FMD vaccine reduced the incident rate of lesions on the pork butt (p<0.01). Overall, 17.81% of the pigs in the heat treatment group had lesions, while the incident rate in the control group was 21.70%. The amount of discarded meat per head of total pigs and per head of pigs with lesions were significantly lower in the heat treatment group than the control group (p<0.01). Thus, the proportion of discarded meat to dressed carcass was lower in the heat treatment group (0.249%) compared with the control group (0.338%) (p<0.01). Farms that rear 1,000 sows can gain 1,863,289 KRW (1,600 USD) in one year when they adopt heat treatment of FMD vaccine before injection. Conclusion: Heat treatment of FMD vaccine using simple heat equipment (water bath) can be effective in reducing lesions caused by FMD vaccination and increase the economic benefits in pig farms.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.725-732
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• 2018

The vaccination for foot-and-mouth disease (FMD) is an effective way to control FMD. However, the injection of FMD vaccine causes abnormalities in pork meat by the incidence of lesions at the injection site. This study was conducted to investigate the inhibition effects of dietary bromelain, a natural protease derived from pineapple stems, on the incidence of lesions at the vaccination site on pigs. A total of 335 pigs (LYD [Landrace ${\times}$ Yorkshire ${\times}$ Duroc]; 7-week-old) were randomly allotted to two dietary treatments: control (basic diet) and bromelain treatment (diet supplemented with bromelain 1 kg/ton). The injection of FMD vaccine was conducted on 56- and 84-day-old pigs. Pigs with the bromelain treatment were fed a diet supplemented with bromelain for 14 days from 5 days before the vaccine injection. After slaughtering the pigs, the number of carcasses that had abnormal meat at the injection site of the vaccine and the amount of abnormal meat, discarded meat, and trimmings were recorded. Pork from the bromelain treated pigs had a lower incidence of abnormal meat caused by vaccine injection as well as a lower amount of abnormal meat, discarded meat, and trimmings than those of the control (p < 0.05). Our result suggests that dietary bromelain could improve the quality of pork meat by inhibiting incidence of lesions at the vaccine injection site.

• Biomolecules & Therapeutics
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• v.31 no.3
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• pp.350-358
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• 2023

Hand-foot-and-mouth disease (HFMD) is a viral infectious disease that occurs in children under 5 years of age. Its main causes are coxsackievirus (CV) and enterovirus (EV). Since there are no efficient therapeutics for HFMD, vaccines are effective in preventing the disease. To develop broad coverage against CV and EV, the development of a bivalent vaccine form is needed. The Mongolian gerbil is an efficient and suitable animal model of EV71 C4a and CVA16 infection used to investigate vaccine efficacy following direct immunization. In this study, Mongolian gerbils were immunized with a bivalent inactivated EV71 C4a and inactivated CVA16 vaccine to test their effectiveness against viral infection. Bivalent vaccine immunization resulted in increased Ag-specific IgG antibody production; specifically, EV71 C4a-specific IgG was increased with medium and high doses and CVA16-specific IgG was increased with all doses of immunization. When gene expression of T cell-biased cytokines was analysed, Th1, Th2, and Th17 responses were found to be highly activated in the high-dose immunization group. Moreover, bivalent vaccine immunization mitigated paralytic signs and increased the survival rate following lethal viral challenges. When the viral RNA content was determined from various organs, all three doses of bivalent vaccine immunization were found to significantly decrease viral amplification. Upon histologic examination, EV71 C4a and CVA16 induced tissue damage to the heart and muscle. However, bivalent vaccine immunization alleviated this in a dose-dependent manner. These results suggest that the bivalent inactivated EV71 C4a/CVA16 vaccine could be a safe and effective candidate HFMD vaccine.