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Human Vaccines & Immunotherapeutics Dec 2024The primary objective of this paper is to serve as a valuable resource for policymakers who are confronted with the evolving landscape of the coronavirus disease 2019... (Review)
Review
The primary objective of this paper is to serve as a valuable resource for policymakers who are confronted with the evolving landscape of the coronavirus disease 2019 (COVID-19), considering both free and cost-based vaccination approaches. The potential consequences of shifting from free to cost-based vaccination are explored, encompassing its impact on global vaccine equity and prioritization, economic well-being, healthcare systems and delivery, public health policies, and vaccine distribution strategies. Examining past studies on willingness to pay for the initial COVID-19 vaccine dose and booster shots provides insights into how individuals value COVID-19 vaccinations and underscores the significance of addressing issues related to affordability. If COVID-19 vaccinations incur expenses, using effective communication strategies that emphasize the importance of vaccination and personal health benefits can increase willingness to pay. Making COVID-19 vaccines accessible through public health programs or health insurance can help alleviate financial barriers and increase vaccination rates.
Topics: Humans; COVID-19 Vaccines; COVID-19; Pandemics; Vaccination; Immunization, Secondary
PubMed: 38359815
DOI: 10.1080/21645515.2024.2313860 -
International Journal of Surgery... May 2024
Topics: Humans; Pakistan; Meningococcal Vaccines; Immunization Programs; Meningococcal Infections
PubMed: 38353754
DOI: 10.1097/JS9.0000000000001196 -
Human Vaccines & Immunotherapeutics Dec 2024Meningococcal vaccination strategies in China are intricate, including multiple vaccines targeting different serogroups. The current National Immunization Program (NIP)...
Meningococcal vaccination strategies in China are intricate, including multiple vaccines targeting different serogroups. The current National Immunization Program (NIP) includes two polysaccharide vaccines for serogroups A and C (MPV-A and MPV-AC), covering limited serogroups and requiring adaptation. This study aims to evaluate the cost-effectiveness of replacing the current strategy with alternative strategies utilizing non-NIP vaccines to inform policy decisions. From a societal perspective, a decision tree-Markov model was constructed to simulate the economic and health consequences of meningococcal disease in a 2019 birth cohort with four vaccination strategies. Epidemiology, vaccine efficacy, cost, and other parameters were derived from previous studies. We conducted sensitivity analyses to assess the robustness of the findings and explored prices for non-NIP vaccines that enable cost-effective strategies. Compared to the current strategy, alternative strategies using quadrivalent polysaccharide vaccine (MPV-4), bivalent conjugate vaccine (MCV-AC), and quadrivalent conjugate vaccine (MCV-4) could avoid 91, 286, and 455 more meningococcal cases. The ICERs were estimated at approximately $250 thousand/QALY, $450 thousand/QALY, and $1.5 million/QALY, all exceeding the threshold of three times GDP per capita. The alternative strategies were not cost-effective. However, if vaccine prices were reduced to $3.9 for MPV-4, $9.9 for MCV-AC, and $12 for MCV-4, the corresponding strategy would be cost-effective. The current meningococcal vaccination strategy in China could effectively prevent the disease at a low cost, but with limited serogroup coverage. Strategies using MPV-4, MCV-AC, or MCV-4 could increase health benefits at a substantial cost, and might become cost-effective if vaccine prices decrease.
Topics: Child; Humans; Cost-Effectiveness Analysis; Vaccines, Conjugate; Cost-Benefit Analysis; Meningococcal Infections; Vaccination; Meningococcal Vaccines; China; Polysaccharides
PubMed: 38348600
DOI: 10.1080/21645515.2024.2313872 -
Journal of Global Health Feb 2024
Topics: Adult; Humans; Respiratory Syncytial Virus, Human; Respiratory Syncytial Virus Infections
PubMed: 38343348
DOI: 10.7189/jogh.14.03008 -
Molecular & Cellular Proteomics : MCP Mar 2024Antigen-antibody interactions play a key role in the immune response post vaccination and the mechanism of action of antibody-based biopharmaceuticals. 4CMenB is a...
Antigen-antibody interactions play a key role in the immune response post vaccination and the mechanism of action of antibody-based biopharmaceuticals. 4CMenB is a multicomponent vaccine against Neisseria meningitidis serogroup B in which factor H binding protein (fHbp) is one of the key antigens. In this study, we use hydrogen/deuterium exchange mass spectrometry (HDX-MS) to identify epitopes in fHbp recognized by polyclonal antibodies (pAb) from two human donors (HDs) vaccinated with 4CMenB. Our HDX-MS data reveal several epitopes recognized by the complex mixture of human pAb. Furthermore, we show that the pAb from the two HDs recognize the same epitope regions. Epitope mapping of total pAb and purified fHbp-specific pAb from the same HD reveals that the two antibody samples recognize the same main epitopes, showing that HDX-MS based epitope mapping can, in this case at least, be performed directly using total IgG pAb samples that have not undergone Ab-selective purification. Two monoclonal antibodies (mAb) were previously produced from B-cell repertoire sequences from one of the HDs and used for epitope mapping of fHbp with HDX-MS. The epitopes identified for the pAb from the same HD in this study, overlap with the epitopes recognized by the two individual mAbs. Overall, HDX-MS epitope mapping appears highly suitable for simultaneous identification of epitopes recognized by pAb from human donors and to thus both guide vaccine development and study basic human immunity to pathogens, including viruses.
Topics: Humans; Epitope Mapping; Neisseria meningitidis; Deuterium; Bacterial Proteins; Meningococcal Infections; Carrier Proteins; Deuterium Exchange Measurement; Complement Factor H; Meningococcal Vaccines; Antigens, Bacterial; Epitopes; Antibodies, Monoclonal; Hydrogen Deuterium Exchange-Mass Spectrometry
PubMed: 38342408
DOI: 10.1016/j.mcpro.2024.100734 -
NPJ Vaccines Feb 2024A decade ago, we described a new approach to discover next generation adjuvants, identifying small-molecule immune potentiators (SMIPs) as Toll-like receptor (TLR)7... (Review)
Review
A decade ago, we described a new approach to discover next generation adjuvants, identifying small-molecule immune potentiators (SMIPs) as Toll-like receptor (TLR)7 agonists. We also optimally formulated these drugs through adsorption to aluminum salts (alum), allowing them to be evaluated with a range of established and early-stage vaccines. Early proof-of-concept studies showed that a TLR7 agonist (TLR7a)-based SMIP, when adsorbed to alum, could perform as an effective adjuvant for a variety of different antigens, in both small and large animals. Studies in rodents demonstrated that the adjuvant enhanced immunogenicity of a recombinant protein-based vaccine against Staphylococcus aureus, and also showed potential to improve existing vaccines against pertussis or meningococcal infection. Extensive evaluations showed that the adjuvant was effective in non-human primates (NHPs), exploiting a mechanism of action that was consistent across the different animal models. The adjuvant formulation (named AS37) has now been advanced into clinical evaluation. A systems biology-based evaluation of the phase I clinical data with a meningococcal C conjugate vaccine showed that the AS37-adjuvanted formulation had an acceptable safety profile, was potent, and activated the expected immune pathways in humans, which was consistent with observations from the NHP studies. In the intervening decade, several alternative TLR7 agonists have also emerged and advanced into clinical development, such as the alum adsorbed TLR7/8 SMIP present in a widely distributed COVID-19 vaccine. This review summarizes the research and early development of the new adjuvant AS37, with an emphasis on the steps taken to allow its progression into clinical evaluations.
PubMed: 38332005
DOI: 10.1038/s41541-024-00810-6 -
The Lancet. Infectious Diseases May 2024The UK transition from a 2 + 1 to a 1 + 1 infant immunisation schedule with the 13-valent pneumococcal conjugate vaccine (PCV13) on Jan 1, 2020, coincided with... (Observational Study)
Observational Study
Invasive pneumococcal disease 3 years after introduction of a reduced 1 + 1 infant 13-valent pneumococcal conjugate vaccine immunisation schedule in England: a prospective national observational surveillance study.
BACKGROUND
The UK transition from a 2 + 1 to a 1 + 1 infant immunisation schedule with the 13-valent pneumococcal conjugate vaccine (PCV13) on Jan 1, 2020, coincided with the start of the COVID-19 pandemic. We describe the epidemiology of invasive pneumococcal disease (IPD) in England over 6 financial years (April 1 to March 31) between 2017-18 and 2022-23.
METHODS
We used prospective national surveillance data, including serotyping and whole-genome sequencing of invasive isolates, to analyse IPD trends in England by age and financial year. We compared breakthrough infections and vaccine failure rates in 2022-23 among children eligible for the 1 + 1 schedule with rates in cohorts of children eligible for the 2 + 1 schedule between 2017-18 and 2019-20. We assessed genomic changes over time by comparing Global Pneumococcal Sequencing Clusters and multilocus sequence types among PCV13 serotypes causing IPD.
FINDINGS
There were 4598 laboratory-confirmed IPD cases in 2022-23, 3025 in 2021-22, 1240 in 2020-21, and 5316 in 2019-20. IPD incidence in 2022-23 was 14% lower than in 2019-20 (incidence rate ratio [IRR] 0·86, 95% CI 0·81-0·91; p<0·001). IPD incidence in 2022-23 compared with 2019-20 was 34% higher in children (aged <15 years) (378 cases vs 292 cases; IRR 1·34, 95% CI 1·08-1·68; p=0·009) and 17% lower in adults (aged 15 years and older; 4220 vs 5024; 0·83, 0·78-0·88; p<0·001). The proportion of PCV13-type IPD increased from 19·4% (95% CI 18·2-20·4; 957 of 4947) in 2019-20 to 29·7% (28·3-31·0; 1283 of 4326) in 2022-23, mainly due to serotype 3, but also serotypes 19F, 19A, and 4, alongside a decrease in non-PCV13 serotypes 8, 12F, and 9N. The increase in IPD incidence due to serotypes 3, 19A, and 19F was driven by clonal expansion of previously circulating strains, whereas serotype 4 expansion was driven by newer strains (ie, sequence types 801 and 15603). Breakthrough infections and vaccine failure rates were similar in children eligible for the 1 + 1 (1·08 per 100 000 person-years) and 2 + 1 (0·76 per 100 000 person-years; IRR 1·42, 95% CI 0·78-2·49; p=0·20) PCV13 schedules.
INTERPRETATION
Overall, IPD incidence in England was lower in 2022-23, 2 years after removal of pandemic restrictions, than in 2019-20. Breakthrough and vaccine failure rates were not significantly different between children who received the 1 + 1 compared with the 2 + 1 PCV13 immunisation schedule. The post-pandemic increase in childhood IPD incidence and especially PCV13-type IPD will require close monitoring.
FUNDING
None.
Topics: Humans; Pneumococcal Vaccines; Pneumococcal Infections; England; Prospective Studies; Infant; Child, Preschool; Child; Streptococcus pneumoniae; Adolescent; Immunization Schedule; Male; Female; Adult; Incidence; Vaccines, Conjugate; Serogroup; SARS-CoV-2; COVID-19; Middle Aged; Young Adult; Whole Genome Sequencing; Aged
PubMed: 38310905
DOI: 10.1016/S1473-3099(23)00706-5 -
Infectious Diseases and Therapy Feb 2024Invasive meningococcal disease (IMD) is a potentially life-threatening disease caused by Neisseria meningitidis infection. We reviewed case reports of IMD from newborns,... (Review)
Review
INTRODUCTION
Invasive meningococcal disease (IMD) is a potentially life-threatening disease caused by Neisseria meningitidis infection. We reviewed case reports of IMD from newborns, infants, children, and adolescents, and described the real-life clinical presentations, diagnoses, treatment paradigms, and clinical outcomes.
METHODS
PubMed and Embase were searched for IMD case reports on patients aged ≤ 19 years published from January 2011 to March 2023 (search terms "Neisseria meningitidis" or "invasive meningococcal disease", and "infant", "children", "paediatric", pediatric", or "adolescent").
RESULTS
We identified 97 publications reporting 184 cases of IMD, including 25 cases with a fatal outcome. Most cases were in adolescents aged 13-19 years (34.2%), followed by children aged 1-5 years (27.6%), children aged 6-12 years (17.1%), infants aged 1-12 months (17.1%), and neonates (3.9%). The most common disease-causing serogroups were W (40.2%), B (31.7%), and C (10.4%). Serogroup W was the most common serogroup in adolescents (17.2%), and serogroup B was the most common in the other age groups, including children aged 1-5 years (11.5%). The most common clinical presentations were meningitis (46.6%) and sepsis (36.8%).
CONCLUSIONS
IMD continues to pose a threat to the health of children and adolescents. While this review was limited to case reports and is not reflective of global epidemiology, adolescents represented the largest group with IMD. Additionally, nearly half of the patients who died were adolescents, emphasizing the importance of monitoring and vaccination in this age group. Different infecting serogroups were predominant in different age groups, highlighting the usefulness of multivalent vaccines to provide the broadest possible protection against IMD. Overall, this review provides useful insights into real-life clinical presentations, treatment paradigms, diagnoses, and clinical outcomes to help clinicians diagnose, treat, and, ultimately, protect patients from this devastating disease.
PubMed: 38285269
DOI: 10.1007/s40121-023-00906-x -
Lancet (London, England) Feb 2024Randomised controlled trials of typhoid conjugate vaccines among children in Africa and Asia have shown high short-term efficacy. Data on the durability of protection...
BACKGROUND
Randomised controlled trials of typhoid conjugate vaccines among children in Africa and Asia have shown high short-term efficacy. Data on the durability of protection beyond 2 years are sparse. We present the final analysis of a randomised controlled trial in Malawi, encompassing more than 4 years of follow-up, with the aim of investigating vaccine efficacy over time and by age group.
METHODS
In this phase 3, double-blind, randomised controlled efficacy trial in Blantyre, Malawi, healthy children aged 9 months to 12 years were randomly assigned (1:1) by an unmasked statistician to receive a single dose of Vi polysaccharide conjugated to tetanus toxoid vaccine (Vi-TT) or meningococcal capsular group A conjugate (MenA) vaccine. Children had to have no previous history of typhoid vaccination and reside in the study areas for inclusion and were recruited from government schools and health centres. Participants, their parents or guardians, and the study team were masked to vaccine allocation. Nurses administering vaccines were unmasked. We did surveillance for febrile illness from vaccination until follow-up completion. The primary outcome was first occurrence of blood culture-confirmed typhoid fever. Eligible children who were randomly assigned and vaccinated were included in the intention-to-treat analyses. This trial is registered at ClinicalTrials.gov, NCT03299426.
FINDINGS
Between Feb 21, 2018, and Sept 27, 2018, 28 130 children were vaccinated; 14 069 were assigned to receive Vi-TT and 14 061 to receive MenA. After a median follow-up of 4·3 years (IQR 4·2-4·5), 24 (39·7 cases per 100 000 person-years) children in the Vi-TT group and 110 (182·7 cases per 100 000 person-years) children in the MenA group were diagnosed with a first episode of blood culture-confirmed typhoid fever. In the intention-to-treat population, efficacy of Vi-TT was 78·3% (95% CI 66·3-86·1), and 163 (129-222) children needed to be vaccinated to prevent one case. Efficacies by age group were 70·6% (6·4-93·0) for children aged 9 months to 2 years; 79·6% (45·8-93·9) for children aged 2-4 years; and 79·3% (63·5-89·0) for children aged 5-12 years.
INTERPRETATION
A single dose of Vi-TT is durably efficacious for at least 4 years among children aged 9 months to 12 years and shows efficacy in all age groups, including children younger than 2 years. These results support current WHO recommendations in typhoid-endemic areas for mass campaigns among children aged 9 months to 15 years, followed by routine introduction in the first 2 years of life.
FUNDING
Bill & Melinda Gates Foundation.
Topics: Child; Humans; Infant; Typhoid Fever; Salmonella typhi; Vaccines, Conjugate; Typhoid-Paratyphoid Vaccines; Malawi; Randomized Controlled Trials as Topic
PubMed: 38281499
DOI: 10.1016/S0140-6736(23)02031-7 -
Emerging Infectious Diseases Feb 2024The rising incidence of invasive meningococcal disease (IMD) caused by Neisseria meningitidis serogroup W in Western Australia, Australia, presents challenges for...
The rising incidence of invasive meningococcal disease (IMD) caused by Neisseria meningitidis serogroup W in Western Australia, Australia, presents challenges for prevention. We assessed the effects of a quadrivalent meningococcal vaccination program using 2012-2020 IMD notification data. Notification rates peaked at 1.8/100,000 population in 2017; rates among Aboriginal and Torres Strait Islander populations were 7 times higher than for other populations. Serogroup W disease exhibited atypical manifestations and increased severity. Of 216 cases, 20 IMD-related deaths occurred; most (19/20) were in unvaccinated persons. After the 2017-2018 targeted vaccination program, notification rates decreased from 1.6/100,000 population in 2018 to 0.9/100,000 population in 2019 and continued to decline in 2020. Vaccine effectiveness (in the 1-4 years age group) using the screening method was 93.6% (95% CI 50.1%-99.2%) in 2018 and 92.5% (95% CI 28.2%-99.2%) in 2019. Strategic planning and prompt implementation of targeted vaccination programs effectively reduce IMD.
Topics: Humans; Western Australia; Meningococcal Vaccines; Bacterial Vaccines; Australia; Meningococcal Infections; Vaccination; Neisseria meningitidis
PubMed: 38270172
DOI: 10.3201/eid3002.230144