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Due to long-term use of immunosuppressant, poor immune function and a higher risk of critical diseases after novel coronavirus pneumonia in kidney transplant recipients, it is of significance to deliver prophylactic vaccination for this high-risk population. Studies have shown that the immune reaction of kidney transplant recipients to novel coronavirus vaccine is significantly lower than that of healthy counterparts. Standard vaccination program in the United States, such as 2 doses of messenger RNA (mRNA) vaccine, fails to provide sufficient protection for kidney transplant recipients. Many studies have proven that increasing the frequency of vaccination for kidney transplant recipients may enhance the vaccine efficacy. Nevertheless, the role of adjusting immunosuppressive therapy in increasing vaccine efficacy remains to be elucidated. In this article, the importance, effectiveness and particularity of novel coronavirus vaccine for kidney transplant recipients and the effect of immunosuppressive therapy on the efficacy of novel coronavirus vaccine were reviewed, aiming to provide reference on the vaccination for kidney transplant recipients.
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Purpose: The existing panels of COVID-19 vaccines are based on the spike protein of an earlier SARS-CoV-2 strain that emerged in Wuhan, China. However, the evolving nature of SARS-CoV-2 has resulted in the emergence of new variants, thereby posing a greater challenge in the management of the disease. India faced a deadlier second wave of infections very recently, and genomic surveillance revealed that the B.1.617 variant and its sublineages are responsible for the majority of the cases. Hence, it's crucial to determine if the current vaccines available can be effective against these variants. Methods: To address this, we performed molecular dynamics (MD) simulation on B.1.617 along with K417G variants and other RBD variants. We studied structural alteration of the spike protein and factors affecting antibody neutralization and immune escape via In silico docking. Results: We found that in seven of the 12 variants studied, there was a structural alteration in the RBD region, further affecting its stability and function. Docking analysis of RBD variants and wild-type strains revealed that these variants have a higher affinity for the ACE2 (angiotensin 2 altered enzymes) receptor. Molecular interaction with CR3022 antibody revealed that binding affinity was less in comparison to wild type, with B.1.617 showing the least binding affinity. Conclusions: The results of the extensive simulations provide novel mechanistic insights into the conformational dynamics and improve our understanding of the enhanced properties of these variants in terms of infectivity, transmissibility, neutralization potential, virulence, and host-viral replication fitness.
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Immunization with regulatory T cell (Treg) epitope peptides to activate and induce Tregs, by which to suppress pathological autoimmune responses and reconstitute a new homeostasis, is a promising therapeutic regimen for autoimmune rheumatic diseases. However, it is usually hard to induce potent peptide-specific immune responses in vivo with small molecular peptides. Bacterial flagellin is one of the agonists triggering innate immune responses. When used as carrier, it shows strong adjuvant activity to its conjugated antigens. In some particular situations, bacterial flagellin can also activate and induce Tregs. Thus if Treg epitope peptides are covalently conjugated to a bacterial flagellin, the conjugates should be able to effectively enhance the Treg-based immune responses via flagellin itself and the adjuvanticity of flagellin to Treg epitope peptides, and thereby enhance the immunotherapeutic effects on autoimmune rheumatic diseases.
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In this study, the swabs were collected among patients with an influenza-like illness (ILI) admitted to 2 sentinel surveillance hospitals of Yantai from April 2014 to August 2017. All specimen were cultured and identified by hemagglutination inhibition assay. Complete sequences of Hemagglutinin (HA) of influenza A were amplified, sequenced and analyzed using molecular and phylogenetic methods. The potential vaccine efficacy were calculated using Pepitope model. The results showed that the antigenicity of A (H3N2) had changed greatly. 8 strains of influenza A (H1N1) pdm09 belonged to subclade 6B.1 and 14 strains clustered in 6B.2. 12 strains of influenza A (H3N2) fell into subgroup 3C.3a and 33 strains clustered in 3C.2a. Several residues at antigen sites and potential glycosylation sites had changed in influenza A strains. Vaccine efficacy of influenza A (H1N1) pdm09 in 2015/2016 and 2016/2017 seasons were 77.29% and 79.11% of that of a perfect match with vaccine strain, meanwhile vaccine efficacy of influenza A (H3N2) in 2014/2015, 2015/2016 and 2016/2017 were-5.18%, 16.97% and 42.05% separately. In conclusion, the influenza A virus circulated in Yantai from 2014 to 2017 presented continual genetic variation. The recommended vaccine strains still afforded protection against influenza A (H1N1) pdm09 strains and provided suboptimal protection against influenza A (H3N2) strains.
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Objective To evaluate the effectiveness and safety of varicella attenuated live vaccine ( VarV) produced by A Co. Ltd. Methods We selected 3 provinces in China and enrolled 15 002 children aged 3-<11 in this random, multicenter study. Participants were randomly divided into two groups: the ex-perimental group and the control group. Every varicella case was collected and recorded to calculate the vac-cine efficacy. Vaccine safety was assessed by means of spontaneous report and regular follow-up visits. Re-sults During the observation period, the incidence of varicella was 0. 147% in the experimental group and 1. 155% in the control group (P<0. 001). The vaccine efficacy was 87. 27%. The adverse reaction rate af-ter vaccination was lower than the rates reported in other literatures. Conclusion The VarV produced by A Co. , Ltd. in China was effective and safe in preventing varicella.
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A Newcastle disease virus (NDV) isolate designated IBS002 was isolated from a commercial broiler farm in Malaysia. The virus was characterised as a virulent strain based on the multiple basic amino acid motif of the fusion (F) cleavage site 112RRRKGF117 and length of the C-terminus extension of the hemagglutinin-neuraminidase (HN) gene. Furthermore, IBS002 was classified as a velogenic NDV with mean death time (MDT) of 51.2 h and intracerebral pathogenicity index (ICPI) of 1.76. A genetic distance analysis based on the full-length F and HN genes showed that both velogenic viruses used in this study, genotype VII NDV isolate IBS002 and genotype VIII NDV isolate AF2240-I, had high genetic variations with genotype II LaSota vaccine. In this study, the protection efficacy of the recombinant genotype VII NDV inactivated vaccine was also evaluated when added to an existing commercial vaccination program against challenge with velogenic NDV IBS002 and NDV AF2240-I in commercial broilers. The results indicated that both LaSota and recombinant genotype VII vaccines offered full protection against challenge with AF2240-I. However, the LaSota vaccine only conferred partial protection against IBS002. In addition, significantly reduced viral shedding was observed in the recombinant genotype VII-vaccinated chickens compared to LaSota-vaccinated chickens.
Subject(s)
Animals , Amino Acids, Basic , Chickens , Genetic Variation , Genotype , Malaysia , Newcastle disease virus , Newcastle Disease , Vaccination , Vaccines , Virulence , Virus SheddingABSTRACT
Human papillomavirus (HPV) is associated with cervical cell changes, genital warts, recurrent respiratory papillomatosis, laryngeal papillomatosis, head and neck cancer, and cervical cancer. Two commercial HPV vaccines have successfully been made available in the clinical field. This review covers the progress of cervical disease by understanding the nature of HPV infection, as well as the relationship between the host factors and HPV vaccine effectiveness. Among these host factors, microbiota has been revealed to influence the development and function of both the innate and adaptive immune systems. Therefore, the composition of the microbiome may ultimately affect vaccine efficacy. Understating the relationship between host factors and HPV infection/vaccine efficacy may prove to be useful in earlier diagnosis, as well as disease prophylaxis.
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Humans , Condylomata Acuminata , Diagnosis , Head and Neck Neoplasms , Immune System , Microbiota , Papilloma , Papillomavirus Infections , Papillomavirus Vaccines , Probiotics , Uterine Cervical NeoplasmsABSTRACT
Although measles is a vaccine preventable disease, its occurrence and outbreaks are common in India. Four remote and inaccessible hamlets, inhabited by the Dukpa tribe, at Buxa Hills under Kalchini Block of Jalpaiguri District, West Bengal experienced a measles outbreak during the months of April-June, 2011. The authors conducted an investigation to assess vaccine coverage, vaccine effi cacy (VE) and to describe the patterns of measles outbreaks in this community. The over-all attack rate was 14.3%; that among males and females were 12.6% and 16.0% respectively (P = 0.189). Attack rate was highest (40%) in 0 to <5 years followed by that in the 5 to <15 years (36.5%). VE was 66.3% (95% of the confi dence interval 46.9-78.6%). There is an urgent need to increase the vaccination coverage through special tactics for reaching the unreached.
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The field of vaccinology was born from the observations by the fathers of vaccination, Edward Jenner and Louis Pasteur, that a permanent, positive change in the way our bodies respond to life-threatening infectious diseases can be obtained by specific challenge with the inactivated infectious agent performed in a controlled manner, avoiding the development of clinical disease upon exposure to the virulent pathogen. Many of the vaccines still in use today were developed on an empirical basis, essentially following the paradigm established by Pasteur, "isolate, inactivate, and inject" the disease-causing microorganism, and are capable of eliciting uniform, long-term immune memory responses that constitute the key to their proven efficacy. However, vaccines for pathogens considered as priority targets of public health concern are still lacking. The literature tends to focus more often on vaccine research problems associated with specific pathogens, but it is increasingly clear that there are common bottlenecks in vaccine research, which need to be solved in order to advance the development of the field as a whole. As part of a group of articles, the objective of the present report is to pinpoint these bottlenecks, exploring the literature for common problems and solutions in vaccine research applied to different situations. Our goal is to stimulate brainstorming among specialists of different fields related to vaccine research and development. Here, we briefly summarize the topics we intend to deal with in this discussion.
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Humans , Vaccines/immunology , Biomedical Research/trends , Drug DesignABSTRACT
In a large Phase III trial conducted in 10 Latin American countries, the safety and efficacy of the live attenuated monovalent rotavirus vaccine RIX4414 was evaluated in 15,183 healthy infants followed up during the first two years of life. Belém was the only site in Brazil included in this multicentre trial. The study in Belém included a subset of 653 infants who were followed up until 24 months of age for protection against severe rotavirus gastroenteritis. These subjects were randomly assigned in a 1:1 ratio to receive two doses of vaccine (n = 328) or two doses of placebo (n = 325) at approximately two and four months of age. Of the 653 enrolled infants, 23 dropped out during the study period. For the combined two-year period, the efficacy of RIX4414 was 72.3% [95% confidence interval (CI) 37.5-89.1%] against severe rotavirus-related gastroenteritis, reaching a protection rate of 81.8% (95% CI 36.4-96.6%) against circulating wild-type G9 rotavirus strains. It is concluded that two doses of RIX4414 are highly efficacious against severe rotavirus gastroenteritis in Belém during the first two years of life and provide high protection against the worldwide emergence and spread of G9P[8] strains.
Subject(s)
Child, Preschool , Female , Humans , Infant , Male , Antibodies, Viral/immunology , Gastroenteritis/prevention & control , Rotavirus Infections/prevention & control , Rotavirus Vaccines/administration & dosage , Administration, Oral , Antibodies, Viral/genetics , Double-Blind Method , Genotype , Gastroenteritis/virology , Rotavirus Infections/virology , Rotavirus Vaccines/adverse effects , Rotavirus Vaccines/immunology , Severity of Illness Index , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/adverse effects , Vaccines, Attenuated/immunologyABSTRACT
OBJECTIVES: During March-May, 2000, a measles outbreak occurred at Youngduk, Korea. This county is divided into two areas with different historical and socioeconomic background. The outbreak occurred in one of these areas. We conducted a comparative epidemiologic study on the two areas in order to evaluate the factors related to the epidemic. MATERIALS AND METHODS: We selected two groups, grades 3 and 5 in a primary schools in each area. We investigated outbreak-related factors using parent-questionnaires, the vaccination history from the students health record and the records concerning the recent measles-outbreak from the local health center. Serologic test on measles-IgG and -IgM antibody was done. RESULTS: The infection rate was 31.6% for the epidemic area and 3.7% for non-the epidemic area according to clinical or serological criteria (p<0.001). No difference was seen in the measles vaccination rate, residence at the time of vaccination or past measles infection history between the two areas. In the epidemic area, the attack rate for the 4-6 year-old MMR booster group(20.5%) was higher than the non-booster group(32.4%), but was not found significantly. Vaccine efficacy was 29.6% in the epidemic area and 87.0% in the non-epidemic area (p<0.001). The IgG level and positive rate were significantly different between the two areas (median 10727 IU/ml, 98.9% in epidemic area; median 346 IU/ml, 85.9% in the non-epidemic area, p<0.001). However, the IgG level and positive rate between the measles-cases and non-cases were not significantly different. CONCLUSIONS: This outbreak took place in mostly vaccinated children. These results suggest that a reduction of herd immunity for immunity failure after vaccination may be one of the feasible factors related to the outbreak pattern in the two areas. The results of the IgG level and positive rate suggest that re-establishment of a normal value for IgG level and of a qualitative method for IgG are needed.
Subject(s)
Child , Humans , Epidemiologic Studies , Immunity, Herd , Immunoglobulin G , Korea , Measles , Reference Values , Serologic Tests , VaccinationABSTRACT
Several measures for vaccine effectiveness have been proposed which go beyond the direct effectiveness measurement which measures the benefit of vaccination to the recipient. In this study, a Micropopulation, Monte-Carlo model of nursing home outbreaks was used to evaluate the different vaccine measures. Simulation sets at five different vaccination levels: 0%. :5%. 50%, 75% and 100% vaccinated were run. Each simulation set was a 1000 outbreaks at a medium influenza level of .08 and an underlying vaccine efficacy of .5. The indirect measures show clearly how the population benefits as the percentage of vaccination increases. The average vaccine effectiveness measure, which compares the vaccinated attack rate with what would have been expected had no vaccine been given, showed a vaccine effectiveness of .540 at 25% vaccination; .759 at 50% vaccination: .866 at 75% vaccination; and .925 at 100% vaccination. These experiments show the usefu1ness of simulation models in presenting interrelated complex information in an understandable format.
Subject(s)
Disease Outbreaks , Influenza, Human , Nursing Homes , VaccinationABSTRACT
PURPOSE: There was marked decline of measles outbreak in the world since the first measles vaccine had been introduced. Recently, however, measles outbreak in the vaccinated children have been reported worldwide, which was ascribed to the possibilities of primary or secondary vaccine failure. We investigated the incidence in the school-aged children in the Kyong-gi Do area, the larger district which covers the urban and rural area, by the questionnaire. METHODS: The questionnaires which were asked to the students' parents of 14 elementary schools in and nearest Sungnam city, Kyong-Gi Do for their present age, experience of measles attack and vaccination, and the age of measles attack. The answers of this questionnaire were analysed by SAS computer program. RESULTS: 1) Measles vaccination rate at 9 months was 70.5% and MMR vaccination rate at 15 months was 91.3%. 2) Measles attack rate among unvaccinated group was 53.8%, and 16.1% in vaccinated group. There was significant low risk of measles attack among vaccinated group than unvaccinated group(relative risk=3.35, p<0.001). 3) Vaccine efficacy of measles in this age group was 69%. 4) Age distribution of measles outbreak reveals bimodal pattern, the graph shows two peak incidence of 1 year-old and 6 years-old. 5) There were no significant differences of measles incidence in the different medical care service center that measles vaccination had been done. CONCLUSIONS: Despite high rate of measles vaccine coverage in Sungnam, the attack rate of measles in the vaccinated population was relatively high. There may be due to primary, secondary vaccine failure or the other factors. The policy of measles vaccination in Korea should be reestablished as soon as possible.