Search Results (907)

Background: Men who have sex with men (MSM) using HIV pre-exposure prophylaxis (PrEP) experience a high burden of human papillomavirus (HPV) infection and related diseases, yet data on HPV vaccination among this group in Brazil remain limited. Aims: The aims of this study were to estimate the prevalence of complete HPV vaccination and to identify factors associated with vaccination completion among MSM using PrEP in Brazil. Methods: We conducted a cross-sectional online survey between May and September 2025 among MSM aged ≥18 years, residing in Brazil and currently using oral PrEP. Participants were recruited through virtual snowball sampling and targeted advertisements on social media and a gay geosocial networking application. Data were collected using a structured, self-administered questionnaire hosted on REDCap^®. Complete HPV vaccination was defined as self-reported receipt of all doses recommended according to the participant’s age and clinical condition. Sociodemographic characteristics, relationship patterns, sexual behaviors, lubricant use during sexual activity, and history of sexually transmitted infections (STIs) were assessed. Adjusted prevalence ratios (aPRs) and 95% confidence intervals (95% CIs) were estimated using Poisson regression with robust (sandwich) variance. Results: A total of 872 MSM using PrEP were included, of whom 59.4% reported complete HPV vaccination. In adjusted analyses, complete vaccination was more frequent among participants reporting both steady and casual partners (aPR = 1.90; 95% CI: 1.36–2.65) or only casual partners (aPR = 1.72; 95% CI: 1.24–2.39), those reporting lubricant use during sexual activity (aPR = 1.41; 95% CI: 1.23–1.61), and those with a diagnosis of chlamydia and/or gonorrhea in the previous 12 months (aPR = 1.22; 95% CI: 1.08–1.36). Conclusions: Although HPV vaccination coverage among MSM using PrEP in Brazil is higher than that reported for MSM in general, it remains incomplete in a population with regular contact with specialized health services. Integrating systematic assessment and delivery of HPV vaccination into PrEP care may help increase vaccination completion and reduce missed opportunities for prevention. Full article

Background: Salmonella is a major zoonotic foodborne pathogen. Conventional poultry vaccines may present limitations in terms of efficacy, safety, and practicality. Objectives: This study focuses on enhancing the immunogenicity and improving the safety of a novel oral vaccination employing inducible toxin–antitoxin (TA) systems, which lead to self-destruction of virulent Salmonella Enteritidis. Methods: A Hok/Sok (HS) TA system was designed to induce cell death upon absence of arabinose. Point mutations were introduced to the Hok toxin promoter to moderate toxin production. A combination of HS and CeaB/CeiB (CC) TA systems was designed to induce cell death both in low di-cation levels or anaerobic conditions. Survival of Salmonella-carrying TA systems was tested in culture and in the Raw264.7 macrophage cell line. One-day old chicks were inoculated with Salmonella carrying the TA system to evaluate bacterial persistence and induction of a protective immune response. Results: Attenuation of the Hok toxin promoter prolonged bacterial survival in vitro. Salmonella carrying the combined TA systems was eliminated completely both in vitro and in inoculated chickens, eliciting high levels of antibodies and conferring protection against challenge with wild-type Salmonella. Conclusions: These findings highlight the potential of the adaptable TA-based vaccination platform to generate safe and efficacious Salmonella vaccines for poultry, contributing to reduced transmission in the food chain. Full article

This study successfully developed an oral vaccine for Type 1 Diabetes utilizing recombinant Lactococcus lactis expressing the GAD65 autoantigen. We conducted an in-depth investigation into its protective mechanisms in NOD mice, with a particular focus on its effects on the gut microbiota and metabolome. The administration of the GAD65-L. lactis vaccine resulted in a significant delay in diabetes onset and the preservation of pancreatic function. Our analyses revealed notable alterations in the gut microbial ecosystem, enhancing its diversity and the abundance of beneficial bacteria. Metabolomic profiling indicated time-dependent changes in metabolic pathways, with a marked enrichment of pyrimidine metabolism at 16 weeks and arachidonic acid metabolism at 24 weeks after vaccination by both GAD65-L. lactis and NZ9000-L. lactis. Integrated correlation analysis identified specific microbiota–metabolite interactions, including associations between Ruminiclostridium and lipid species in the GAD65-L. lactis group. These modifications in the microbial community and metabolic landscape were accompanied by enhanced immunoregulatory responses in intestinal LPLs, including expanded Treg populations and suppressed CD8⁺ T cells, a rising trend in IL-10-producing naive dendritic cells, and increased concentrations of TGF-β. Full article

Microneedle (MN) technologies have emerged as a groundbreaking platform for transdermal and intradermal drug delivery, offering a minimally invasive alternative to oral and parenteral routes. Unlike passive transdermal systems, MNs allow the permeation of hydrophilic macromolecules, such as peptides, proteins, and vaccines, by penetrating the stratum corneum barrier without causing pain or tissue damage, unlike hypodermic needles. Recent advances in materials science, microfabrication, and biomedical engineering have enabled the development of various MN types, including solid, coated, dissolving, hollow, hydrogel-forming, and hybrid designs. Each type has unique mechanisms, fabrication techniques, and pharmacokinetic profiles, providing customized solutions for a range of therapeutic applications. The integration of 3D printing technologies and stimulus-responsive polymers into MN systems has enabled patches that combine drug delivery with real-time physiological sensing. Over the years, MN applications have grown beyond vaccines to include the delivery of insulin, anticancer agents, contraceptives, and various cosmeceutical ingredients, highlighting the versatility of this platform. Despite this progress, broader clinical and commercial adoption is still limited by issues such as scalable and reliable manufacturing, patient acceptance, and meeting regulatory expectations. Overcoming these barriers will require coordinated efforts across engineering, clinical research, and regulatory science. This review thoroughly summarizes MN technologies, beginning with their classification and drug-delivery mechanisms, and then explores innovations, therapeutic uses, and translational challenges. It concludes with a critical analysis of clinical case studies and a future outlook for global healthcare. By comparing technological progress with regulatory and commercial hurdles, this article highlights the opportunities and limitations of MN systems as a next-generation drug-delivery platform. Full article

Glaesserella parasuis (G. parasuis) is a key pathogen responsible for swine respiratory disease, and the development of broadly protective vaccines is hampered by its high antigenic diversity. The iron-acquisition protein TbpB is a conserved vaccine candidate, but the cellular immune responses it elicits, particularly T-cell subset dynamics during immunization and challenge, remain insufficiently defined. This study characterized these responses after oral immunization of colostrum-deprived piglets with the TbpB^Y167A mutant. Ten colostrum-deprived piglets were allocated to immunized and non-immunized (PBS) groups, immunized at days 15 and 30 of life and subsequently challenged with G. parasuis (45 days old); peripheral blood mononuclear cells were collected at baseline, after each immunization, and at 1 and 3 days post-infection. Multiparametric flow cytometry was used to quantify major leukocyte subsets and T-cell phenotypes defined by sIgM, CD172a, CD3, TCRγδ, CD8α/β, CD4 and CD27 expression. Booster immunization induced significant expansion of B cells (p < 0.01), TCRγδ T cells (p < 0.01), CD8⁺ αβ T cells (p < 0.001) and CD4⁺ memory T cells (p < 0.01) in immunized piglets compared with controls. After challenge, CD8⁺ cytotoxic T cells in immunized animals rapidly shifted from naïve to memory phenotypes, peaking at 48–72 h (p < 0.01). These biphasic T-cell dynamics are consistent with the protective efficacy previously demonstrated for this vaccine in colostrum-deprived piglets, and support a key contribution of TCRγδ, CD8⁺ cytotoxic and CD4⁺ memory T cells to immunity against G. parasuis and to the design of next-generation vaccines. Full article

Background/Objectives: Toxoplasma gondii (T. gondii) dense granule antigen 14 (GRA14) is a parasitophorous vacuole membrane protein that plays a critical role in the development of chronic-stage cysts. However, its potential as a vaccine antigen and long-term immunity have not been evaluated using a virus-like particle (VLP) platform. Methods: influenza matrix protein (M1)-based VLPs displaying GRA14 were generated. Female BALB/c mice were intranasally immunized with the VLP vaccine and orally challenged with lethal ME49 cysts either 10 weeks or 32 weeks after prime vaccination for short-term and long-term immunity evaluation, respectively. Results: GRA14 VLP vaccination elicited higher levels of T. gondii-specific IgG, IgG1, and IgG2a antibody responses in sera compared to non-immunized controls. Upon challenge infection, elevated IgG- and IgA-secreting plasma cells, germinal center B cells, and memory B cells were observed, and CD4⁺, CD8⁺ T-cells, as well as both Th1 (IFN-γ) and Th2 (IL-4, IL-5) cytokines, were also increased. For the short-term immunity study, vaccinated mice exhibited suppressed cerebral inflammation, significantly reduced brain cyst burdens, maintained stable body weight, and achieved 100% survival. For the long-term study, GRA14 VLPs sustained elevated IgG and IgG1 levels as well as conferred partial yet significant protection, with lower cyst loads and 83% survival. Conclusions: GRA14 VLPs induce durable, balanced humoral and cellular immunity and provide both short-term and long-term protection against lethal chronic toxoplasmosis, supporting their potential as promising vaccine candidates. Full article

The COVID-19 pandemic accelerated vaccine innovation but also exposed weaknesses in global access and manufacturing. Yeast-based platforms, particularly Saccharomyces cerevisiae and Pichia pastoris, also known as Komagataella phaffii, offer a practical complement to vector systems. These eukaryotic microorganisms combine safety, scalability, and cost-effectiveness with the ability to express complex antigens and assemble virus-like particles. Building on the success of the recombinant hepatitis B vaccine, recent advances in glycoengineering, CRISPR-based host optimization, and surface display technologies have expanded the utility of yeast-based platforms for the rapid development of vaccines. Yeast-derived SARS-CoV-2 receptor-binding domain (RBD) subunit vaccines, such as Corbevax and Abdala (CIGB-66), demonstrate that affordable, immunogenic, and thermostable products are feasible at scale. Emerging innovations in glycan humanization, thermostable formulations, and oral or mucosal delivery highlight the potential of yeast-based vaccines for decentralized manufacturing and equitable pandemic preparedness. This review summarizes recent technical and clinical progress in yeast-based vaccine research, positioning these platforms as accessible and adaptable tools for future outbreak responses and global immunization strategies. Full article

Background: Non-typhoidal Salmonella (NTS) is a major foodborne pathogen, with poultry products, especially eggs, being the primary source of human infections. Current serovar-specific poultry vaccines effectively reduce targeted Salmonella serovars but may inadvertently promote the emergence of untargeted serovars within poultry flocks. Therefore, novel vaccine candidates providing broad cross-serovar protection are needed to improve overall effectiveness of Salmonella control programs. Objectives: This study evaluated the immunogenicity of the novel subunit vaccine candidate InvG and assessed its ability to reduce Salmonella colonization in vaccinated laying hens and their progeny through maternally derived antibodies transferred via egg yolk. Methodology: Three experiments were performed. Experiment I evaluated the immunogenicity of purified recombinant InvG by (a) measuring anti-InvG antibodies using an enzyme-linked immunosorbent assay (ELISA) and (b) completing transcriptomic profiling of immune responses in vaccinated chickens. Vaccinated chickens were subsequently challenged with Salmonella Enteritidis to assess the efficacy of anti InvG antibodies in reducing intestinal colonization of Salmonella. Experiment II involved immunizing hens with InvG, to evaluate passive transfer of antibodies via egg yolk and the protective efficacy of maternally derived antibodies against Salmonella challenge. Passive transfer was assessed by measuring IgY antibodies in hen serum, egg yolk, and progeny serum, as well as secretory IgA (sIgA) antibodies in progeny intestinal washings using ELISA. Protective efficacy was evaluated by orally challenging one-day-old chicks with three different Salmonella serovars. Experiment III assessed the persistence of anti-InvG antibodies in the serum of vaccinated hens and their transfer into eggs following two doses of InvG. Results: InvG vaccination induced robust IgY antibody responses in hens, with efficient maternal antibody transfer to progeny via egg yolk. A statistically significant reduction in Salmonella colonization was observed in both vaccinated hens and their progeny. Conclusions: These findings demonstrate that InvG represents a promising subunit vaccine candidate for Salmonella control in poultry and warrants further investigation towards development as a broadly protective commercial poultry vaccine against Salmonella. Full article

Transmissible gastroenteritis (TGE), caused by the TGE virus (TGEV), is a highly contagious enteric disease characterized by vomiting, dehydration, and watery diarrhea. It mainly endangers piglets within two weeks of age, with a 100% mortality rate, inflicting severe economic losses on the global swine industry. Since enteric tropism of the virus and mucosa serves as the first line of defense against viral invasion, an oral vaccine inducing sufficient secretory immunoglobulin A (SIgA) antibodies in animals should be developed. Being a generally recognized as safe (GRAS) microorganism, Bacillus subtilis can form endospores under extreme environmental conditions, which confer resistance to the hostile gastric environment and have been widely employed as delivery vehicles for oral vaccines owing to their immunoadjuvant activity and non-specific antidiarrheal effects. In this study, the AD antigenic epitope of the TGEV S protein was selected as the immunogen. The mature peptide of the B subunit of the heat-labile enterotoxin from enterotoxigenic Escherichia coli served as a mucosal adjuvant, and B. subtilis WB800N was used as the delivery host to construct the recombinant strain pHT43-LTB-AD/WB800N. After confirming the successful expression of the target protein, oral immunization was performed using mice as a model. The results demonstrated that this recombinant strain induced robust mucosal, humoral, and cellular immunity, along with considerable levels of neutralizing antibodies. These findings indicate that recombinant B. subtilis could serve as an oral vaccine candidate to combat TGEV infections. Full article

Porcine reproductive and respiratory syndrome virus (PRRSV) remains a major cause of economic loss in the swine industry, and highly pathogenic variants such as NADC34-like PRRSV highlight the need for antiviral strategies that complement vaccination. In this field study, we evaluated the efficacy of AlimenWOW, a rottlerin–lipid formulation, in grower–finisher pigs under commercial conditions using AI-based respiratory monitoring. A total of 2000 pigs were assigned to four groups: AlimenWOW G1 (PRRSV-stable source farm), AlimenWOW G2 (PRRSV-unstable source farm), Control 1 (antibiotic), and Control 2 (antipyretic). Respiratory Health Status (ReHS) and a derived Clinical Cough Index (CCI = 100 − ReHS) were continuously recorded with SoundTalks^®, and oral fluid PRRSV load, serology, clinical outcomes, and productivity were assessed over 4 weeks. AlimenWOW G2 showed a marked improvement in ReHS from severely compromised baseline values to levels comparable with healthy status, while both control groups remained low; CCI was significantly lower in AlimenWOW G2 than in controls from day 14 onward (p ≤ 0.0001). AlimenWOW treatment was associated with reduced PRRSV titers in oral fluid, lower mortality and wasting rates, and improved feed conversion with lower feed costs compared with controls. These findings indicate that AlimenWOW, integrated with AI-based acoustic monitoring, can improve respiratory health and mitigate PRRSV-associated clinical and economic losses, supporting its use as a complementary tool in PRRSV control programs. Full article

Group A rotaviruses (RVAs) remain the leading cause of acute gastroenteritis (AGE) in young children in low- and middle-income countries. In Brazil, the oral attenuated RVA vaccine (Rotarix^®), monovalent genotype G1P[8], is distributed by the national immunization program and has drastically reduced morbidity and mortality associated with RVA etiology. In this study, Rotarix^® G1P[8] was detected using specific qRT-PCR from the fecal shedding of children living in the Amazon region, and 18.3% (29/158) were positive and 75.8% (22/29) presented with AGE. The VP4 (VP8*) gene of these sheddings, submitted to Sanger nucleotide sequencing, showed an occurrence of mutations, including the silent mutation at 144C > G (one child) and the following missense mutations— 499T > C (F167L) (two children), 644G > C (C215S) (one child), and 787G > A (E263K) (one child). These mutations had no impact on the protein model structure in silico deduced from the VP4 (VP8*) mutants. The in silico protein model deduced from the VP4 (VP8*) nucleotide sequences, bound to type 1H sugar antigens (H1) and its precursor Lac-para-N-biose (LNB), had a stronger binding to the G1P[8] genotype, when compared to G3P[8]. Rotarix^® shedding was higher in HBGA secretors than in non-secretors (79.3%; 23/29). A total of 11.4% (18/158) of children with Rotarix^® G1P[8] shedding were unvaccinated, indicating the occurrence of indirect protection. Stability evidence of Rotarix^® VP4 (VP8*) spike protein from samples collected in vivo is presented. Full article

Background: Women’s empowerment has been significantly associated with improved child health outcomes. Cambodia, amid a rapid socioeconomic transition, offers a critical setting to examine how advancements in women’s empowerment over the past decade have influenced child immunization completion within the first two years of life. Methods: Data from the Cambodia Demographic and Health Surveys conducted in 2010, 2014, and 2021–22, encompassing 9222 women with recent births, were analyzed. Empowerment was measured across literacy and information access, employment, and decision-making domains. Multinomial logistic regression assessed associations between empowerment factors and completion of oral polio (OPV), diphtheria–tetanus–pertussis (DTP), pneumococcal conjugate (PCV), and measles–rubella (MR) vaccines, adjusting for demographic and socioeconomic variables. Results: Between 2010 and 2022, women’s empowerment in Cambodia improved significantly, marked by higher literacy rates, nearly half of women completing primary education, and expanded digital access, with 82.4% owning mobile phones and approximately 50% using the internet daily. While non-working women slightly increased, agricultural employment declined by 20%, and cash earnings rose from 48.7% to 82.5%. Most women participated in major household decision-making, either independently or jointly. Completion rates for OPV, DTP, and PCV ranged from 79% to 83%, while just over half of children were fully vaccinated against measles. Higher maternal education and cash earnings were positively associated with OPV, DTP, and PCV completion but negatively associated with measles vaccination. Women in agricultural work were less likely to complete measles vaccination for their children than non-working women. Joint decision-making regarding the use of respondents’ income was associated with a higher likelihood of measles non-completion (OR = 2.26, 95% CI: 1.13–4.51), whereas joint decision-making about respondents’ health care was associated with a higher likelihood of measles completion (OR = 0.42, 95% CI: 0.21–0.83). Conclusions: Women’s empowerment remains a key determinant of vaccination outcomes in Cambodia. The distinct pattern observed for measles suggests that vaccines scheduled for older ages encounter greater structural and behavioral barriers. To overcome these challenges, strategies should focus on enhancing defaulter tracking, implementing reminder systems, expanding outreach and catch-up programs, and improving the convenience of vaccination services. Full article

Objective: To explore the problems with non-National Immunization Program vaccinations in Hubei Province and to provide the basis for follow-up vaccination and management. Methods: Vaccination data on non-NIP/NIP vaccine doses were extracted from the Hubei Provincial Immunization Planning Information Management System. Descriptive epidemiological analyses were conducted to examine dose administration, vaccine-type composition, regional distribution, and substitution patterns. The trend χ² test was used to assess temporal significance. Multistage regression analysis was performed using Joinpoint software. Results: From 2011 to 2024, a total of 91,009,259 doses (annual average: 6,500,661) with 35 types of non-NIP vaccines were administered in Hubei Province, China. The top five vaccines by doses administered were influenza vaccine, rabies vaccine, Hemophilus influenzae type b conjugate vaccine, varicella attenuated live vaccine, and enterovirus 71 inactivated vaccine. Before 2024 (2011–2023), vaccine utilization showed a long-term upward trend: per 10,000, population usage rose from 657.07 (2011) to a peak of 2393.21 (2023) (Increase: 264.22%, χ² = 138.62, p < 0.05) (AAPC = 10.92%, p < 0.05) and non-NIP’s share of total vaccines increased from 25.52% (2011) to 65.95% (2023), (Increase: 154.33%, χ² = 89.47, p < 0.05) (AAPC = 8.74%, p < 0.05). A notable reversal occurred in 2024. Non-NIP doses dropped from 13,971,544 (2023) to 10,238,861 (2024) with population usage falling from 2393.21 (2023) to 1755.03 (2024) (decrease: 26.66%) per 10,000, with the top three declines being in inactivated polio vaccine (IPV) (decrease: 49.53%), influenza vaccine (decrease: 44.21%), and oral rotavirus attenuated live vaccine (decrease: 43.50%). The total number of substitutive non-National Immunization Program (non-NIP) vaccine doses administered reached 16,618,755, with an overall substitution rate of 10.10%. This rate showed a steady upward trend from 5.57% in 2011 to 24.74% in 2023 (trend χ² = 15.11, p < 0.05), yet it increased to 28.03% in 2024. Conclusions: Non-NIP vaccines and NIP-substitute use grew steadily for over a decade, then contracted sharply in 2024. Decision-makers should investigate the sudden dip, differentiate discretionary from replacement demand, and reallocate funds to sustain equity and prevent further erosion of coverage. Full article

Tetanus is a life-threatening neurological disease affecting vertebrate species, including primates. Here, we present a case of severe generalized tetanus in a juvenile male chimpanzee (Pan troglodytes) that was rescued from the illegal wildlife trade and admitted to a rehabilitation center in the Republic of Congo. Upon arrival, the chimpanzee presented with deep, contaminated constrictive wounds, trismus, generalized rigidity, and stimulus-induced tonic spasms accompanied by transient apnea, while remaining conscious. A presumptive clinical diagnosis was made, after which integrated care began immediately. This included meticulous wound debridement and irrigation, passive immunization with antitoxin, initiation of active immunization, metronidazole with adjunctive penicillin G, diazepam-based spasm control, multimodal analgesia, and low-stimulation nursing with oxygen supplementation, enteral nutrition, and temporary urinary catheterization. Aerobic wound culture yielded mixed flora, and a Gram stain of the feces showed large Gram-positive rods with terminal spores. Hematology tests revealed leucopenia with neutropenia and severe thrombocytopenia. The spasms ceased by day 5, at which point the diazepam dose was reduced and oral intake was increased. By week 8, he had made a full clinical recovery and was successfully reintegrated into his group. This case supports the use of pragmatic, sanctuary-adapted protocols and systematic vaccination. Full article

Background: Clínica Esperanza/Hope Clinic (CEHC), a free clinic for low-income, uninsured, Spanish-speaking patients, located in Providence, RI, piloted an intervention to improve vaccination rates. This program, named “Oportuna Vacuna” (OV) aimed to assess vaccine hesitancy in the post-pandemic period and measure improvements to vaccine uptake after integrating healthcare provider (HCP) and patient education with vaccine workflow adjustments. Methods: OV was initiated in January 2023. Culturally attuned and linguistically appropriate vaccine-focused educational programs were developed and provided to patients and HCPs, while workflow modifications to streamline vaccine administration were implemented during clinic visits. Structured pre- and post-intervention chart reviews were conducted and (oral- and) paper-based knowledge, attitudes, and practices surveys were administered to selected staff and patients to assess knowledge, attitudes, and vaccine confidence before and after the interventions. A total of 816 charts were reviewed prior to the intervention; 709 charts were reviewed post-intervention. A total of 72 patient and 10 HCP pre- and post- intervention surveys were completed. Vaccine uptake was compared to the uptake in 2022. Results: Overall vaccination rates at the clinic increased by more than 400% compared to the prior year. Patients and HCPs demonstrated increased vaccine knowledge and confidence, particularly with respect to COVID-19 and HPV vaccines. In contrast, chart reviews of individual patients revealed only a slight improvement in vaccination completion rates for patients over the 1-year period. Conclusion: Substantial increases in vaccine administration rates across multiple vaccine types highlight the effectiveness of OV, mainly for first time patients, at CEHC. Clinic workflow modifications improved vaccination efficiency and increased vaccine uptake. Educational sessions on vaccines were well received by patients and staff. Overall knowledge about vaccines improved during the intervention among staff and HCPs. Patients reported higher trust in HCPs compared to other sources for vaccine information. Full article