Vaccination Purposes Research Articles

Tetanus Vaccine Knowledge, Beliefs, and Attitudes Among Syrian Pregnant Women in Türkiye: A Qualitative Study

Background: In this qualitative study, we aimed to evaluate the knowledge, beliefs, and attitudes of Syrian pregnant women living in Türkiye toward tetanus vaccination, vaccine hesitations, and the perceived benefits and harms of the tetanus vaccine. Methods: In face-to-face, in-depth interviews, an open-ended, semi-structured interview guide was used by an interviewer and translator who spoke Arabic, which is the mother tongue of the participants. Codes, themes, and subthemes were created. Results: In the study, face-to-face in-depth interviews were conducted with a total of 16 pregnant women. The median age of the pregnant women was 26.5 years (18.0–41.0). The median time since they arrived in Türkiye as migrants was 8.5 years (3.0–10.0). The themes were “Beliefs about vaccines”, “Information about vaccines”, “Knowledge, beliefs and attitudes about tetanus vaccine”, “Reasons for vaccination desire”, “Reasons for not being vaccinated”, and “Problems experienced while receiving health services”. Pregnant women mostly mentioned that vaccines have benefits. Most of the women stated that tetanus vaccine is needed to protect from diseases. There were no women thinking that vaccines are harmful. Some of them only mentioned the minor side effects observed after vaccination. Participants mentioned that they get information about vaccines from relatives such as family and friends, health professionals, television, and social media. However, some women talked about the fact that they had no knowledge about vaccines. A lack of knowledge and not visiting the health institution were the reasons for not being vaccinated. Conclusions: Although participants mostly believed that vaccination is necessary and has benefits, some women had no idea about the exact purpose of vaccines. This lack of knowledge may cause vaccine hesitancy and refusal.

Optimization of Enterovirus-like Particle Production and Purification Using Design of Experiments

Hand, foot, and mouth disease (HFMD) represents an emerging health concern whose main causative agents are Coxsackievirus A6 (CVA6) and enterovirus A71 (EV71). The lack of a CVA6 vaccine and the rise of new HFMD-causing strains due to the containment of established HFMD-causing viruses necessitates the search for alternative vaccine technologies, including virus-like particle (VLP) vaccine candidates. While studies have demonstrated that production of enterovirus-like particles in various organisms can be achieved by expression of the viral P1 structural proteins and the 3CD protease, optimization based on the interplay between the three most commonly altered infection parameters (multiplicity of infection (MOI), viable cell density at the time of infection (VCD), and the infection period) is often not investigated. To address this challenge, we have performed Design of Experiments (DoE) to optimize the production of CVA6 and EV71 VLPs. Our results indicate that CVA6 VLP production peaks at high MOI, high VCD, and long infection periods. Our subsequent downstream purification processes yielded 38 mg and 158 mg of purified CVA6 and EV71 VLPs from 1 L crude harvest, respectively. This translates into thousands of potential vaccine doses and highlights the economic potential of enterovirus-like particles for vaccine purposes.

Pulmonary Delivery of Nonviral Nucleic Acid-Based Vaccines With Spotlight on Gold Nanoparticles.

Nucleic acid-based vaccines are leading-edge tools in developing next-generation preventative care. Much research has been done to convert vaccine gene therapy from an invasive to a noninvasive administration approach. The lung's large surface area and permeability make the pulmonary route a promising noninvasive delivery option for vaccines, with systemic and local applications. This review summarizes the challenges and the approaches that have been carried out to optimize the delivery of nucleic acids through the pulmonary route for vaccination purposes in recent years, with a spotlight on gold nanoparticles (AuNPs). Nonviral delivery systems have been widely explored, and AuNPs with their unique properties are emerging as promising tools for nucleic acid vaccines due to surface functionalization with mucus-penetrating polymers and targeting moieties that can bypass the barriers in pulmonary delivery and successfully deliver nucleic acids to the cells of interest. However, while promising, several challenges remain including selectively overcoming the lungs' immunological surveillance and adhesive mucus.

Perception Analysis of Breastfeeding Mother Behavior in Implementing the Covid-19 Vaccine at the Campurejo Health Center

Perception is a model of individual health beliefs in determining whether or not to carry out health behavior. This could be one of the reasons why breastfeeding mothers do not want to be vaccinated. In addition, the lack of understanding of breastfeeding mothers regarding the purpose and benefits of vaccination will cause breastfeeding mothers not to want to be vaccinated. The aim of the study was to determine the effect of Perception on the Behavior of Breastfeeding Mothers in implementing the Covid-19 Vaccine. The research design used was analytical observational with a cross sectional approach. The population in this study were all breastfeeding mothers at Campurejo health centers. The sample size is 30 respondents. Sample selectedusing purposive sampling technique. Then analyzed using the ordinal regression test withα ≤ 0.05.

Multiparameter Flow Cytometric Analysis of the Conventional and Monocyte-Derived DC Compartment in the Murine Spleen.

Dendritic cells (DCs) are present in almost all tissues, where they act as sentinels involved in innate recognition and the initiation of adaptive immune responses. The DC family consists of several cell lineages that are heterogenous in their development, phenotype, and function. Within these DC lineages, further subdivisions exist, resulting in smaller, less characterized subpopulations, each with its unique immunomodulatory capabilities. Given the interest in utilizing DC for experimental studies and for vaccination purposes, it becomes increasingly crucial to thoroughly classify and characterize these diverse DC subpopulations. This understanding is vital for comprehending their relative contribution to the initiation, regulation, and propagation of immune responses. To facilitate such investigation, we here provide an easy and ready-to-use multicolor flow cytometry staining panel for the analysis of conventional DC, plasmacytoid DC, and monocyte-derived DC populations isolated from mouse spleens. This adaptable panel can be easily customized for the analysis of other tissue-specific DC populations, providing a valuable tool for DC research.

Efficacy of Chitosan-N-Arginine Chitosomes in mRNA Delivery and Cell Viability Enhancement.

Cationic lipid-based carriers are recognized for their ability to complex with mRNA and effectively deliver the mRNA for vaccination and therapeutic purposes. However, the significant cytotoxicity of these carriers often restricts their practical application. In the present study, polymer-lipid hybrid nanoparticles, termed chitosomes, incorporating chitosan-N-arginine (CSA) with the DOTAP cationic lipid and the DOPE helper lipid, were synthesized and evaluated. The addition of CSA to the lipid formulations improved their physicochemical stability and enhanced mRNA complexation, resulting in high transfection rates in the HeLa and HEK293T cell lines. However, the transfection efficiency was low in the NIH-3T3 cell line, indicating a cell type-specific response to chitosomes. Importantly, CSA significantly reduced the cytotoxicity typically associated with DOTAP. Overall, the present study indicated that optimizing the ratio of CSA to DOTAP is crucial for developing mRNA nanocarriers to achieve high transfection efficiency and reduce cytotoxicity across different cell lines.

“Vaccines protect both you and your newborn:” A discourse analysis of risk and uncertainty in information about vaccination in pregnancy

Health governance during pregnancy is grounded in cultural norms about good mothering, which centre around self-sacrifice and perceived conflicts between maternal and fetal bodies. Nonetheless, many health choices in pregnancy should have mutual benefits and risks for maternal and fetal bodies, including vaccination during pregnancy. This manuscript presents results from a discourse analysis of 440 texts about vaccines that are recommended in pregnancy in Canada, including inactivated influenza, tetanus-diphtheria-acellular-pertussis, and COVID-19 vaccines. Texts include publicly available online information (e.g., webpages, printouts, posters, videos, and other materials) developed by various authoritative institutions (e.g., public health services, professional organizations, vaccine manufacturers). This study contributes to feminist and risk theorist critiques of public health discourse by exploring how texts deploy emotionally laden technical discourses that govern pregnant individuals towards divergent goals. Specifically, they are governed towards socially desirable health decisions (e.g., vaccination acceptance) and towards agonizing over decision-making as “good mothers.” I analyze how texts pursue this divergent governance in three ways, by deploying discourses that reify conflict between maternal and fetal bodies, organizing the work of making choices around gendered power relations, and activating emotions around mothering responsibilities. My analysis compares how such governance differs across products by available evidence and by the intended purpose of vaccination to protect maternal and/or fetal bodies. I conclude by discussing the value of combining governmentality and cultural approaches to risk theory to understand how the interface of public health and mothering discourses reproduce power relations, and suggest recommendations on how to lessen that reproduction.

Motivation, Cues to Action, and Barriers to COVID-19 Vaccine Uptake: A Qualitative Application of the Health Belief Model among Women in Rural Zambia.

Vaccine hesitancy has played a major role in slowing the global COVID-19 response. Using cross-sectional, primarily qualitative data collected in four rural districts in Zambia, we aimed to explore community perceptions of COVID-19 disease and vaccines, including perceived motivators, cues to action, benefits, and barriers to vaccine uptake as guided by the Health Belief Model. In-depth interviews (IDIs) were conducted in late 2021 with women of reproductive age who were enrolled in an early childhood development study. Although two-thirds of the 106 respondents reported low perceived risk of catching COVID-19, they expressed concern that the COVID-19 pandemic had impacted their daily lives and feared effects of the disease. They had generally positive beliefs that the vaccine would be accepted among their communities when it became more widely available. Reported motivators to vaccine uptake included desire for protection against COVID-19 and understanding vaccine purpose, due to ongoing education from health personnel, neighbors, friends, radio, and church leaders. Misinformation or reported bad experiences served as cues away from vaccine uptake. Examples of misinformation included the vaccine causing COVID-19 or another disease and death and vaccines being associated with the devil and against Christian beliefs. Accounts of pain after receiving the vaccine also discouraged uptake. Perceived benefits included a desire to be protected from the disease, belief in the effectiveness of the vaccine, fear of catching COVID-19, and belief the vaccine would limit negative effects. Health system implementers and policy makers should consider recipient motivators and cues to action to further increase vaccination rates.

An Overview of the Types of Adjuvants Used in the Vaccination Industry And Their Mechanisms of Action.

The widespread use of efficient vaccines against infectious diseases is regarded as one of the most significant advancements in public health and techniques for preventing and protecting against infectious diseases and cancer. Because the purpose of vaccination is to elicit an appropriate, powerful, and long-lasting immune response against the pathogen, compounds such as adjuvants must be used to enhance these responses. Adjuvants have been widely used since their discovery to boost immune responses, prevent diseases, and activate protective immunity. Today, several types of adjuvants with varying properties are available for specific applications. Adjuvants are supramolecular substances or complexes that strengthen and prolong the immune response to antigens. These compounds have long-term immunological effects and are low in toxicity. They also lower the amount of antigen or the number of immunogenic reactions needed to improve vaccine efficacy and are used in specific populations. This article provides an overview of the adjuvants commonly used in the vaccination industry, their respective mechanisms of action, and discusses how they function to stimulate the immune system. Understanding the mechanisms of action of adjuvants is crucial for the development of effective and safe vaccines.

Zoonoses and pet owners: A survey on risk perception in Northern Italy

Veterinary and human medicine are focused on the issue of emerging and re-emerging diseases, which are especially represented by zoonosis that could be a threat for public health. Zoonotic risk may come from pets: some canine and/or feline viral, bacterial, parasitic, protozoal or mycotic diseases can be transmitted directly to humans. There are several strategies to prevent the transmission of such zoonosis, and among them vaccination plays an important role. Through a survey carried out in Northern Italy aimed to collect information regarding owners’ knowledge and perception of the zoonotic risks associated with three zoonoses (rabies, leptospirosis, and dermatophytosis), it was demonstrated that dog owners tend to adhere more consistently to their pets’ vaccination schedules and are more receptive to changes in vaccination scheduling compared to cat owners. This study also suggests that cat owners predominantly visit veterinarians for vaccination purposes, whereas dog owners seek veterinary services for a variety of reasons. The survey highlighted the ongoing need to enhance owners’ understanding of zoonoses affecting their pets and also the protective role of vaccines. Veterinarians should undertake the responsibility of educating, reassuring, and informing pet owners about the significance of vaccines for their pets and for public health.

What sources do individuals use to validate arguments in scientific discourses today? An exploratory study of YouTube comments on vaccination

PurposeThis study aims to explore scientific discourses on vaccination in YouTube comments using the Connectivism theory as a foundational guide in the inquiry of understanding knowledge seeking and sharing. The authors sought to understand how individuals share and seek information by using external sources through URL links to validate their arguments.Design/methodology/approachUsing content analysis, the authors extracted and analysed 584 random comments with URL links from eight YouTube videos scientifically addressing the purpose of vaccines. The comments were coded by stance (pro, anti, and neutral) and the type of resource to observe how their links were used.FindingsThe results showed that URL links were composed of quotes, questions, and opinions. Many sources came from research papers, conspiracy websites, or other videos. Some of the comments did not accurately reflect the information from research papers and showed little scientific reasoning. This suggests the need for critical evaluation among individuals when finding information online.Research limitations/implicationsThe findings can be expanded to explore different types of information literacy practices in the comment section of social media for both informal and formal environments.Practical implicationsYouTube is useful in fostering scientific discourse and information-seeking/sharing practices among individuals. However, considering the inaccuracy of content deliverance, educators and individuals will need to consider how to teach/conduct information literacy skills when implementing social media for educational purposes.Originality/valueOnly a few studies have conducted research on comments using URL links, the originality of sources and how the sources were used in argumentation.

NMR-based metabolomic investigation of dogs with acute flaccid paralysis due to tick paralysis.

Acute flaccid paralysis (AFP) is a complex clinical syndrome with various aetiologies. If untreated, AFP may lead to death due to failure of respiratory muscles. Tick paralysis, which is a noninfectious neurologic syndrome of AFP, occurs following tick attachment, engorgement, and injection of tick saliva toxins. There is no specific diagnostic test for tick paralysis, and mortality increases as definitive diagnosis is delayed. Although metabolomic investigation of tick saliva was conducted, there is a lack of research on metabolomic evaluation of hosts affected by tick paralysis. Thus, the aim of this study is to investigate metabolomic changes in serum samples of dogs with tick paralysis due to Rhipicephalus sanguineus using NMR-based metabolomics and to identify potential diagnostic/prognostic markers. Forty dogs infested with R. sanguineus, with clinical findings compatible with AFP and with a confirmed tick paralysis diagnosis ex juvantibus, constituted the Paralysis Group. Ten healthy dogs, which were admitted either for vaccination and/or check-up purposes, constituted the Control Group. After the confirmation tick paralysis, medical history, vaccination and nutritional status, body surface area and estimated tick numbers of all the dogs were noted. Physical examination included body temperature, heart and respiratory rate, capillary refill time evaluation and Modified Glasgow Coma Scale calculation. Serum samples were extracted from venous blood samples of all the dogs and were prepared for NMR analysis, and NMR-based metabolomics identification and quantification were performed. NMR-based serum metabolomics of the present study revealed distinct up/down-regulated expressions, presenting a promising avenue. Moreover, it was observed that energy metabolism and especially liver functions were impaired in dogs with tick paralysis, and not only the respiratory system but also the kidneys were affected. It was concluded that the present approach may help to better understand the pathological mechanisms developing in cases of AFP due to tick paralysis.

A Pilot Study on the Knowledge, Attitude, and Practice of Mothers About Their Children's Vaccination in a Medical Institute in Jharkhand, India.

Introduction Immunisation is one of the key public health instruments to combat childhood morbidity and mortality. However, the lack of mothers' knowledge and motivation to vaccinate their children has affected vaccination programs and vaccination coverage rate in the state of Jharkhand. Therefore, addressing this knowledge gap, our study aims to evaluate the extent of mothers' understanding of the effects and aspects of vaccination for their children. Materials and method This is a cross-sectional study conductedat the paediatric vaccination clinic of Rajendra Institute of Medical Sciences (RIMS), Ranchi between October 2022 and September 2023. The sample population included 200 mothers as participants (18 years and above). The survey was done with a self-administered questionnaire of questions about socio-demographic factors, mothers' knowledge, and mothers' practices, and answers were consolidated in the form of a table. Results The majority of participants in this study were below 25 years of age and were literate. The missed vaccination percentage was also significantly higher among illiterates, mothers below 30 years of age, and unemployed ones. Among the respondents, 73.3% of illiterate mothers, 56% of those below 30 years of age, and 64% of unemployed mothers missed their children's vaccination schedule. Among the mothers, 75% did not know the names of vaccine-preventable diseases. Of the respondents, 50% believed intercurrent illnesses like fever and the common cold to be side effects and contraindications of vaccines. Among the mothers, 65% never posed any questions to the paediatrician. Of the mothers, 97% safely kept the vaccination card and 82% relied on government or public health centres for vaccination purposes. Conclusion The majority of our population was in favour of vaccinating their children but there existed a huge lacuna in their knowledge about vaccination. This study concludes that firmer measures have to be exercised to bridge this knowledge gap. Only this can improve the vaccination coverage rate.

Nanoemulsions and nanocapsules as carriers for the development of intranasal mRNA vaccines

The global emergency of coronavirus disease 2019 (COVID-19) has spurred extensive worldwide efforts to develop vaccines for protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our contribution to this global endeavor involved the development of a diverse library of nanocarriers, as alternatives to lipid nanoparticles (LNPs), including nanoemulsions (NEs) and nanocapsules (NCs), with the aim of protecting and delivering messenger ribonucleic acid (mRNA) for nasal vaccination purposes. A wide range of prototypes underwent rigorous screening through a series of in vitro and in vivo experiments, encompassing assessments of cellular transfection, cytotoxicity, and intramuscular administration of a model mRNA for protein translation. As a result, two promising candidates were identified for nasal administration. One of them was a NE incorporating a combination of an ionizable lipid (C12-200) and cationic lipid (DOTAP), both intended to condense mRNA, along with DOPE, which is known to facilitate endosomal escape. This NE exhibited a size of 120 nm and a highly positive surface charge (+ 50 mV). Another candidate was an NC formulation comprising the same components and endowed with a dextran sulfate shell. This formulation showed a size of 130 nm and a moderate negative surface charge (-16 mV). Upon intranasal administration of mRNA encoding for ovalbumin (mOVA) associated with optimized versions of the said NE and NCs, a robust antigen-specific CD8 + T cell response was observed. These findings underscore the potential of NEs and polymeric NCs in advancing mRNA vaccine development for combating infectious diseases.Graphical

Intravenous Immunization with Triple Auxotrophs of Mycobacterium tuberculosis : A novel vaccine strategy against tuberculosis.

Tuberculosis, caused by Mycobacterium tuberculosis ( Mtb ), remains a leading infectious cause of mortality worldwide despite widespread use of the BCG vaccine and the availability of sterilizing pharmacopoeia. Recent research indicates that the intravenous administration of BCG confers sterilizing immunity against Mtb pulmonary challenge in non-human primates. However, while BCG is relatively safe, complications such as disseminated BCGosis have been observed in immunocompromised individuals. Double auxotrophic mutants of Mtb lacking the ability to synthesize leucine and pantothenate are safe and sterilized in immunocompromised mice and SIV-infected Rhesus macaques. We examined how immunization with a Mtb triple auxotrophic strain, mc 2 7902, which cannot synthesize leucine, pantothenate, and arginine, protects immunocompetent mice from a virulent Mtb infection. The route of immunization was a crucial factor for protection with mc 2 7902 with intravenous immunization being 100 times more effective in protecting immunocompetent mice from Mtb challenge when compared to conventional subcutaneous vaccination with BCG. To further increase the safety of the attenuated auxotroph for vaccine purposes, the type VII secretion system Esx1 responsible for BCG attenuation was deleted in mc 2 7902. When tested by prime-boost immunization of immunocompetent mice followed by aerosol challenge with virulent Mtb , mc 2 7902 Δ esx1 provided similar protection to mc 2 7902. This robust protection against Mtb infection conferred by mc 2 7902 and mc 2 7902 Δ esx1 in a mouse model paves the way for new TB vaccine development using highly attenuated, auxotrophic Mtb strains.

Uncertainties beyond preparedness: COVID-19 vaccination in Senegal.

Vaccination is one of the most recognised strategies in public health for preventing the spread of epidemics, and the availability of a vaccine is often expected by health actors to be a 'game-changer'. However, the COVID-19 (coronavirus disease 2019) vaccine in Senegal was not the magic bullet that the international community expected. A very low vaccination coverage rate (less than 10% by April 2023) was observed in this country, once considered a model in West Africa for its epidemic response. Beyond the population's alleged hesitancy to be vaccinated, was a lack of preparedness to blame? Previous analyses show that outbreak preparation limited to standard interventions is not sufficient in the face of the social, cultural, and political configurations of each epidemic context and that uncertainty limits response capacity. This paper examines the social life of the COVID-19 vaccine to identify the forms and contextual dimensions of uncertainty related to immunisation in Senegal. The authors explore how vaccination was implemented and compare experiences with the preparedness process, to offer insight on uncertainties. Using Stirling's theoretical model that defines various expressions of incertitude, the authors identify four nexuses at various stages of the social life of COVID-19 vaccine in Senegal: (1) material uncertainty related to vaccine availability, (2) ambiguity of the population about the purpose of vaccination and the risks of the disease, (3) uncertainty related to side effects, and (4) uncertainty about vaccination strategies shared by scientific and health authorities. These uncertainties were only partly considered in the preparedness process, for they are related to systemic structural dimensions and reflect the impact of global/regional powers on the local level. The findings of this research are relevant not only to support better communication around vaccines in Senegal but also more generally to the prevention of emerging epidemics shaped by human behaviours.

Humoral and Cellular Immune Response on COVID-19 Patients and Sinovac Vaccine Participants

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 is a new SARS-CoV virus. A person who is infected with this virus will induce both humoral and cellular immune responses. Herd immunity can be achieved through vaccination. The purpose of vaccination is the formation of antibodies capable of neutralizing coronavirus against the receptor binding domain. This study aimed to determine the differences between humoral and cellular immune responses between confirmed COVID-19 patients and Sinovac vaccine participants. This observational analytic study with a prospective cohort approach was conducted between March to October 2021. Fifty subjects (25 officers who had received vaccinations for COVID-19 patients and 25 COVID-19 patients treated at the Dr. Moewardi General Hospital) and met the inclusion and exclusion criteria were enrolled. Different tests were carried out to see the difference between the levels of CD8+ T cells and anti-SARS-CoV-2 antibodies in the vaccine group and the COVID-19 patient group. There was no significant difference in humoral immune response (anti-SARS-CoV-2) between the vaccine group and COVID-19 patient group [33.93 (0.4–196.6) U/L vs. 101.28±158.59 U/L; p=0.409], but there was a significant difference in cellular immune response (CD8+) between the vaccine group and COVID-19 patient group [878.52±47368 cells/µL vs. 270.16±213.64 cells/µL; p=0.001]. CD8 assay can be used as a parameter to differentiate the cellular immune response between COVID-19 patients and COVID-19 vaccine recipients.

The mechanical properties of lipid nanoparticles depend on the type of biomacromolecule they are loaded with.

For drug delivery systems, the mechanical properties of drug carriers are suspected to play a crucial role in the delivery process. However, there is a lack of reliable methods available to measure the mechanical properties of drug carriers, which hampers the establishment of a link between delivery efficiency and the mechanical properties of carriers. Lipid nanoparticles (LNPs) are advanced systems for delivering nucleic acids to target cell populations for vaccination purposes (mRNA) or the development of new drugs. Hence, it is crucial to develop reliable techniques to measure the mechanical properties of LNPs. In this article, we used AFM to image and probe the mechanical properties of LNPs which are loaded with two different biopolymers either pDNA or mRNA. Imaging the LNPs before and after indentation, as well as recording the retraction curve, enables us to obtain more insight into how the AFM tip penetrates into the particle and to determine whether the deformation of the LNPs is reversible. For pDNA, the indentation by the tip leads to irreversible rupture of the LNPs, while the deformation is reversible for the mRNA-loaded LNPs. Moreover, the forces reached for pDNA are higher than for mRNA. These results pave the way toward the establishment of the link between the LNP formulation and the delivery efficiency.

Deciphering the human antibody response against Burkholderia pseudomallei during melioidosis using a comprehensive immunoproteome approach.

The environmental bacterium Burkholderia pseudomallei causes the often fatal and massively underreported infectious disease melioidosis. Antigens inducing protective immunity in experimental models have recently been identified and serodiagnostic tools have been improved. However, further elucidation of the antigenic repertoire of B. pseudomallei during human infection for diagnostic and vaccine purposes is required. The adaptation of B. pseudomallei to very different habitats is reflected by a huge genome and a selective transcriptional response to a variety of conditions. We, therefore, hypothesized that exposure of B. pseudomallei to culture conditions mimicking habitats encountered in the human host might unravel novel antigens that are recognized by melioidosis patients. In this study, B. pseudomallei was exposed to various stress and growth conditions, including anaerobiosis, acid stress, oxidative stress, iron starvation and osmotic stress. Immunogenic proteins were identified by probing two-dimensional Western blots of B. pseudomallei intracellular and extracellular protein extracts with sera from melioidosis patients and controls and subsequent MALDI-TOF MS. Among B. pseudomallei specific immunogenic signals, 90 % (55/61) of extracellular immunogenic proteins were identified by acid, osmotic or oxidative stress. A total of 84 % (44/52) of intracellular antigens originated from the stationary growth phase, acidic, oxidative and anaerobic conditions. The majority of the extracellular and intracellular protein antigens were identified in only one of the various stress conditions. Sixty-three immunoreactive proteins and an additional 38 candidates from a literature screening were heterologously expressed and subjected to dot blot analysis using melioidosis sera and controls. Our experiments confirmed melioidosis-specific signals in 58 of our immunoproteome candidates. These include 15 antigens with average signal ratios (melioidosis:controls) greater than 10 and another 26 with average ratios greater than 5, including new promising serodiagnostic candidates with a very high signal-to-noise ratio. Our study shows that a comprehensive B. pseudomallei immunoproteomics approach, using conditions which are likely to be encountered during infection, can identify novel antibody targets previously unrecognized in human melioidosis.

Shift in dominant genotypes of Japanese encephalitis virus and its impact on current vaccination strategies.

Japanese encephalitis (JE) is a zoonotic ailment from the Japanese encephalitis virus (JEV). JEV belongs to the flavivirus genus and is categorized into a solitary serotype consisting of five genetically diverse genotypes (I, II, III, IV, and V). The JEV genotype III (GIII) was the prevailing strain responsible for multiple outbreaks in countries endemic to JEV until 1990. In recent years, significant improvements have occurred in the epidemiology of JE, encompassing the geographical expansion of the epidemic zone and the displacement of prevailing genotypes. The dominant genotype of the JEV has undergone a progressive shift from GIII to GI due to variations in its adaptability within avian populations. From 2021 to 2022, Australia encountered an epidemic of viral encephalitis resulting from infection with the GIV JEV pathogen. The current human viral encephalitis caused by GIV JEV is the initial outbreak since its initial discovery in Indonesia during the late 1970s. Furthermore, following a time frame of 50 years, the detection and isolation of GV JEV have been reported in Culex mosquitoes across China and South Korea. Evidence suggests that the prevalence of GIV and GV JEV epidemic regions may be on the rise, posing a significant threat to public safety and the sustainable growth of animal husbandry. The global approach to preventing and managing JE predominantly revolves around utilizing the GIII strain vaccine for vaccination purposes. Nevertheless, research has demonstrated that the antibodies generated by the GIII strain vaccine exhibit limited capacity to neutralize the GI and GV strains. Consequently, these antibodies cannot protect against JEV challenge caused by animal GI and GV strains. The limited cross-protective and neutralizing effects observed between various genotypes may be attributed to the low homology of the E protein with other genotypes. In addition, due to the GIV JEV outbreak in Australia, further experiments are needed to evaluate the protective efficiency of the current GIII based JE vaccine against GIV JEV. The alteration of the prevailing genotype of JEV and the subsequent enlargement of the geographical extent of the epidemic have presented novel obstacles in JE prevention and control. This paper examines the emerging features of the JE epidemic in recent years and the associated problems concerning prevention and control.