Vaccine最新文献

Avian infectious bronchitis virus (IBV) is responsible for a highly contagious disease that poses a significant threat to the poultry industry due to its high rates of evolution. The occurrence of vaccination failure can frequently be attributed to the emergence of novel strains that exhibit antigenic divergence from conventional vaccine strains. This study aims to evaluate the safety and efficacy of the Eg/1212B-based live attenuated virus vaccine indicated for immunization of chickens against nephropathogenic GI-23 variant strains reported globally. Studies were designed in compliance with European Pharmacopeia Ph. Eur. 0442. The attenuated vaccine virus did not exhibit any tendency to revert or increase in virulence after five back-passages in SPF chickens. Ciliostasis scores and kidney lesions (histology) were comparable between vaccinated and control birds. No chicken showed clinical signs of an infection with IBV or died from causes attributable to the vaccine after receiving a 10× overdose. A single vaccination was able to protect the birds in a challenge model with a recent European wild-type IBV strain. The study demonstrated an onset of immunity of 21 days and a duration of immunity lasting up to 56 days. Vaccination administered individually through the ocular route resulted in a protection rate of 100 % to 85 %, whereas mass application by spraying offered a protection rate of 85 % to 80 %. In conclusion, the safety and efficacy data confirm a positive benefit/risk balance, and the investigated product can be considered a suitable vaccine candidate for controlling avian infectious bronchitis nephropathogenic variant strains related to GI-23.

The development of a protective HIV vaccine remains a challenge given the high antigenic diversity and mutational rate of the virus, which leads to viral escape and establishment of reservoirs in the host. Modern antigen design can guide immune responses towards conserved sites, consensus sequences or normally subdominant epitopes, thus enabling the development of broadly neutralizing antibodies and polyfunctional lymphocyte responses. Conventional epitope vaccines can often be impaired by low immunogenicity, a limitation that may be overcome by using a carrier system. In this work, Virus-Like Particles (VLPs) of the B19 human parvovirus were used as a carrier system for multiple HIV-1 epitopes displayed on the surface. Epitopes were selected based on being the binding site of broadly neutralizing antibodies (bnAbs) in patients. Full capsid assembly was confirmed by dynamic light scattering and morphology was confirmed by transmission electron imaging. The resulting chimeric VLPs were termed "VLP-MHIV-A". Antigenicity was confirmed by HIV+ patient sera binding to the chimeric VLP-MHIV-A. To evaluate immunogenicity, female C57bl/6 mice were immunized with the chimeric VLPs either via the intramuscular or subcutaneous route, specific humoral and cellular responses were evaluated, and neutralizing activity was measured in an in vitro reporter cell system. Substantial antibodies against whole-VLPs were induced in serum and vaginal lavages for both immunization routes. Antibody responses against the CD4 binding site, V3 loop and several epitopes of gp41 were detected. Both immunization routes demonstrated neutralizing activity; however, the I.M. route was more effective, showing significant neutralizing activity with up to 50 % inhibition of a tier 1 clade B virus infection. Taken as a whole, these results show that chimeric VLPs are an effective antigen capable of inducing HIV-1 specific antibodies with neutralizing activity.

In Brazil, at least four lineages of influenza A virus circulate pig population: 2009 H1N1 flu pandemic (pH1N1), human-seasonal origin H3N2, H1N1 and H1N2 (huH1 lineages) viruses. Studies related to the occurrence of swine influenza A virus (SIAV) in Brazilian herds have been detecting an increase of occurrence of huH1 lineages. This study aimed to construct recombinant vaccines against the huH1N1 virus and test the immunogens in a murine model. The virus was constructed by reverse genetics using plasmids encoding the HA and NA sequences from a wild huH1N1 virus isolated from an infected pig. Amplified virus was inactivated, and oil-in-water (OW) and gel polymer (GP) adjuvants were used to formulate the vaccines. C57Bl6 mice received two doses with 3 weeks interval by the intramuscular route. Animals were randomly divided into 8 groups (G1-G8): G1 received OW vaccine and G2 PBS plus OW adjuvant; G3 received GP vaccine and G4 PBS plus GP adjuvant; G5 received the live virus by the intranasal route while G6 only PBS; G7 and G8 did not receive any treatment. Serum samples were collected before vaccination and after the first and second dose. Except for G8, three weeks post boost animals were challenged with a wild huH1N1 virus and observed for weight changes. After infection, bronchoalveolar lavage fluid (BALF) and lungs were collected from animals of each group for viral titers and immunohistochemistry (IHC) analysis, respectively. After booster, vaccinated groups seroconverted and the vaccines induced protection upon challenge. Reverse Genetics technique can be used to produce new and quickly updated swine influenza vaccines which is promising to control the virus in Brazilian herds. Future studies may focus on using the technology to produce multivalent recombinant vaccines against distinct strains of SIAVs circulating in Brazilian pig herds.

Vaccines and diagnostic tools stand out as among the most influential advancements in public health, credited with averting an estimated 6 million deaths annually and substantially alleviating the burden of infectious disease. Despite this progress, the global imperative to prevent, detect, and combat infectious disease persists. Regrettably, hundreds of thousands of lives are still lost due to inadequate access to vaccines and diagnostics. A critical obstacle in accessibility lies in the requirement of reliable cold chain for their transportation and storage, a resource that remains inadequate in many regions, particularly in the developing world. Various factors, including socio-economic disparities, biological complexities, and manufacturing processes, exert significant influence on the availability and integrity of vaccines and diagnostic materials. This review aims to explore the multifaceted issue of inequality in access to disease control tools, examining the vulnerabilities of vaccines and diagnostics while also investigating recent advancements that offer promising solutions to improve thermal stability.

Objective: To evaluate whether children with type 1 diabetes mellitus (T1DM) have optimal humoral immune response to pneumococcal polysaccharide vaccination (PPSV23) and to study factors affecting that response.

Methods: In this prospective pilot study, we recruited 29 children with T1DM who were vaccine naïve to PPSV23 and assessed serum-serotype specific IgG at baseline and 4-6 weeks post-immunization. We tested association between independent variables (age, gender, body mass index (BMI), hemoglobin A1c (HbA1c), glucose variability, and time in range assessed by continuous glucose monitors (CGM), insulin dose and outcome (log-2-fold change of immunoassay response between pre- and post-immunization testing) using linear regression.

Results: Eighty-eight percent of children (22/25) who completed the study had overall appropriate response with a median 4.2-fold change following immunization. When assessing PPSV23-exclusive serotypes, there was a statistically significant correlation between increasing age and greater response (0.16 log2-fold change per year, 95 % CI (0.014 to 0.3), p = 0.033). Higher BMI for age (p = 0.085) and a lower coefficient of glucose variation from CGM following immunization (p = 0.067) also coincided with greater vaccine response, with correlation statistically significant for certain pneumococcal serotypes for both.

Conclusions: Response to pneumococcal vaccination has not previously been assessed in children with T1DM, and our study demonstrates robust humoral immune response to PPSV23 vaccination in these children. Larger studies with a diverse representation and longer follow up to assess how humoral seroconversion correlates with clinical response to PPSV23 in this vulnerable population are warranted.

Background: The introduction of the 10-valent pneumococcal conjugate vaccine (PCV10) for nationwide childhood immunization in 2010 led to a significant reduction in colonization and invasive pneumococcal disease (IPD) by vaccine serotypes in young. However, non-vaccine serotypes have emerged, and serotype 19A is now the leading cause of IPD in Brazil.

Methods: We analyzed 32 serotype 19A isolates of Streptococcus pneumoniae recovered from children and adults who attended different health facilities in the state of Rio de Janeiro, Brazil, between 2010 and 2023. The capsular types of the isolates were determined by sequential multiplex PCR or by cpsB gene sequencing. All isolates were subjected to antimicrobial susceptibility testing and MLST.

Results: Of the 32 serotype 19A isolates, 29 (90.6 %) isolates were recovered from children aged ≤5 years and three (9.4 %) isolates were recovered from adults. Nineteen (59.4 %) isolates were associated with colonization, and 13 (40.6 %) isolates were from diseases. All isolates were susceptible to chloramphenicol, levofloxacin, linezolid, rifampin, and vancomycin. The highest frequencies of non-susceptibility (intermediate + resistant) were observed for sulfamethoxazole-trimethoprim (n = 30; 93.8 %), penicillin (n = 24; 75 %), and erythromycin (n = 23; 71.9 %). Twenty-two (68.8 %) isolates were multidrug resistant (MDR). MICs for penicillin among penicillin-non-susceptible pneumococci (PNSP) ranged from 0.12 to 8.0 μg/mL. MICs for erythromycin ranged from 0.064 to >256 μg/mL. MICs for ceftriaxone ranged from 0.023 to 4 μg/mL. The most common genetic lineages were ST733 (n = 7; 21.9 %), mostly found before and in the early years of PCV10 introduction, and CC320 (n = 25; 78.1 %), mostly found in the late-PCV10 period. All 25 isolates within CC320 were PNSP and mostly (n = 22; 88 %) MDR.

Conclusions: We observed a shift in antimicrobial susceptibility profiles and genetic lineages after long-term use of PCV, mostly PCV10, for routine childhood immunization, characterized by clonal expansion of the MDR lineage CC320.

Background: Trust in governments has been decreasing in recent years, especially during the Covid-19 pandemic, where low-trust societies showed reduced compliance with disease control measures. Few studies have examined how trust in authorities changed over the pandemic. This study investigated the trajectory of public trust in the Singapore government's vaccine recommendations during this period.

Methods: 1138 participants completed three online surveys between June 2021 and April 2022. Variables included traditional and online media use, sense of duty to follow government recommendations, self-efficacy in protecting oneself without vaccination, perceived vaccine benefits and trust in government vaccine advice. Growth models were used to examine trends in trust over time.

Results: Trust in government vaccine advice decreased during the pandemic. Traditional media use was positively related to trust in government while online media use showed a negative association. Respondents who viewed following government vaccine recommendations as their choice were less likely to trust the government longitudinally than those who perceived it as their duty. Traditional media users who viewed following advice as their duty had the highest trust across time, while the lowest trust was observed for online media users who viewed following recommendations as their choice. While respondents with higher self-efficacy in protecting against Covid-19 without vaccination showed less trust in the government initially, they showed a smaller decrease in trust over time than those with lower self-efficacy. Stronger beliefs in vaccine benefits were associated with slower decrease in trust over time.

Conclusions: This is one of the first studies to investigate government trust longitudinally in Asia during a crisis. Findings indicate that governments of high-trust societies cannot be complacent during health crises. Messaging strategies that cultivate civic mindedness may promote positive vaccination beliefs and government trust. More attention should be paid to mitigating effects of online media information-seeking on government trust during crises.

To address the challenges posed by influenza, its associated complications, and economic burden, the World Health Organization recommends a vaccination rate exceeding 75 % for populations at elevated risk of severe diseases. Presently, vaccination rates in Germany severely lag behind. To augment these rates, pilot projects have been initiated, allowing community pharmacists to administer vaccines. This study aimed to investigate the the acceptability of pharmacy-led influenza vaccinations among clients and pharmacists, clients' motivations to get vaccinated in community pharmacies, and the rate of adverse events during this process. Data were obtained through anonymous questionnaires from influenza vaccination pilot projects in various German regions between 2020 and 2023. The questionnaire consisted of two sections: one for the vaccinating pharmacist to record and document the vaccination process and one for the recipient, focusing on their experiences and views. In total 11,571 responses were evaluated. Notably, 44 % of participants mentioned they would not have sought vaccination outside a pharmacy setting. This percentage was higher (65 %) in those receiving their first influenza vaccination. Vaccinees reported high levels of satisfaction with the supplied information (88.5 %) and vaccination procedure (93.8 %). Furthermore, clients declared a high willingness to repeat the vaccination (93.9 %) and the possibility of receiving other vaccinations in pharmacies (79.7 %). Among all surveyees, only nine reported adverse reactions post pharmacy-administered vaccination, with none necessitating emergency intervention. Pharmacy-led influenza vaccinations were identified as safe, well-received by vaccinees and effective in increasing vaccination acceptability with the potential to enhance vaccination rates across diverse demographics in Germany.