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A malaria vaccine which has been developed with the help of Oxford University scientists is up to 78% effective in the youngest children, new data suggests.
Last year the R21/Matrix-M vaccine was recommended for use by the World Health Organisation (WHO).
New data from a phase 3 trial in African children confirms the jab is effective and safe.
Researchers immunised more than 4,800 young children in a trial in Burkina Faso, Kenya, Mali and Tanzania and found on average 78% efficacy in the five to 17-month age group over the first year.
The Lancet study on R21/Matrix-M phase 3 trials marks a significant advancement in our battle against this global threat
Adar Poonawalla, Serum Institute of India
The experts say that so far no other vaccine has reported more than 55% effectiveness in the same age group.
According to the findings, published in The Lancet, a booster dose at a year maintained good efficacy over the following six to 12 months.
The overall efficacy was between 68% and 75% for children aged five to 36-months-old.
So far, 25 million doses have been manufactured and made ready for roll-out by the Serum Institute of India (SII) in the next three to four months.
Significantly increased immune responses to the vaccine, and slightly higher vaccine efficacy, were observed in five to 17-month-olds compared to 18 to 36-month-olds, supporting planned vaccine deployment initially from five months of age in African children.
Malaria is the largest cause of death in young African children, with 600,000 dying every year.
Two vaccines have recently achieved and completed WHO pre-qualification, and initial deployments are starting early this year.
Professor Adrian Hill, chief investigator of the R21/Matrix-M phase 3 trial, said: The continued high efficacy of this new vaccine in field trials is very encouraging, and consistent with the high efficacy and excellent durability observed in a smaller four-year phase 2b trial.
Audrey Duncanson, innovations transition manager at Wellcome, said: Malaria still remains a huge global health risk for nearly half of the worlds population, with the burden of this disease predominantly in African countries causing approximately 600,000 deaths in children under the age of five years.
The results from this recent phase 3 trial of the malaria vaccine, R21, holds huge potential for a transformative impact on malaria in children.
This is an important step towards getting a highly effective, safe, readily accessible affordable vaccine to protect children from malaria in African countries.
Adar Poonawalla, chief executive of SSI, said: The Lancet study on R21/Matrix-M phase 3 trials marks a significant advancement in our battle against this global threat.
We are dedicated to making this vaccine available, especially in Africa, where malaria poses a substantial threat to millions of lives, bringing us closer to a malaria-free world.
The vaccine is cheap, costing between two US dollars (1.65) and four dollars (3.30) per dose.
At least 28 countries in Africa plan to introduce a WHO-recommended malaria jab as part of their national immunisation programmes.
Matrix-M adjuvant is manufactured by Novavax AB and provided to SII for formulation into the final vaccine drug product.
An adjuvant is an ingredient used in some vaccines to enhance the bodys immune response, which helps them to work better.
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The clinics will be open in Hallowell and Presque Isle. An insurance card is not needed to receive the vaccines.
Author: newscentermaine.com
Published: 6:32 PM EST February 4, 2024
Updated: 6:32 PM EST February 4, 2024
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4 February 2024
Image source, Getty Images
Vaccine rates in Newcastle, Middlesbrough and Hartlepool are too low, health officials have warned
Health bosses are urging parents to rebook any missed mumps, measles and rubella vaccine (MMR) appointments.
Data showed the North East and north Cumbria had the highest uptake in England, but second doses fell below what is required to avoid outbreaks.
Parts of Newcastle, Middlesbrough and Hartlepool are at risk because numbers are "not high enough".
One health chief said measles is a highly infectious disease but "completely preventable".
Dangers including blindness, deafness and swelling of the brain.
Children require two doses of the MMR vaccine, the first dose given around their first birthday and the second dose given at three years and four months old.
Both doses are needed to ensure full and lasting protection against MMR, according to the NHS.
NHS North of England Care System Support (NECS) data shows in 2022-23, of the 33,937 five- years-olds in the North East and north Cumbria, 96% received their first MMR vaccination however, only 91% received their second.
Dr Neil O'Brien, medical director at the North East and North Cumbria Integrated Care Board, said: "Spending just 15 minutes or more in direct contact with someone infected is enough to catch measles, making it one of the most infectious diseases in the world."
Dr O'Brien added: "Whilst overall MMR rates in our region are good, there are still some localised places where it is not high enough to prevent a rapid spread of measles; including areas of Newcastle, Middlesbrough and Hartlepool."
Cumbria's director of public health Colin Cox said: "Measles can be a very serious illness but getting vaccinated is safe, free of charge and offers the best possible protection."
ROCHESTER, N.Y. (WROC) The Center for Disease Control and Prevention told News 8 Friday they recently sent out a notice to healthcare providers after more than 150 reports of the wrong RSV vaccinations was given to pregnant women and children.
News 8 inquired with the CDC after a caller was wondering why she wasnt able to get the RSV vaccine after getting a prescription from her OB-GYN.
After a response from the CDC said the vaccine is administered from September to January, they also said their vaccine tracker system, Vaccine Adverse Event Reporting System, reported more than 150 children and pregnant women were given the wrong vaccine by doctors offices and pharmacies.
With the RSV vaccine only recently being approved for pregnant women. If they choose to, they are supposed to receive a dose of the maternal RSV vaccine abrysvo.
During weeks 32 through 36 of pregnancy, administered before or during RSV season. Instead, they were receiving the GSK vaccine, Arexvy which is not approved for use during pregnancy.
An OB-GYN with Rochester Regional Health who told News 8 while there were no mix-ups in their healthcare system, she explained the importance of receiving the correct vaccine.
The biggest issue would be that they wouldnt be able to protect their baby, Dr. Fran Haydanek with Rochester Regional Health. Through vaccination of the pregnant patient, we still have ways to protect babies once theyre born. There are medications for babies, and I know a little less about that since thats not my area of expertise. So, there would still possibly be the opportunity to protect babies that way once theyre born, but they just wouldnt be able to pass that immunity on through pregnancy.
The CDC said in their statement to News 8 that while it is rare, vaccine administration errors are known to occur and have the potential to increase after a new vaccine is introduced and reiterated, they have reached out to administrators to educate them.
While rare, vaccine administration errors are known to occur and may increase after a new vaccine or product is introduced. To prevent mix-ups, CDC has reached out to clinicians to educate them about the proper administration of the new RSV vaccines and to alert them that misadministrations, while uncommon, have occurred. Education and additional vigilance will reduce the likelihood of errors.
Overview of the 2023-24 COVID-19 Vaccine
In the ongoing battle against COVID-19, the effectiveness of vaccination remains a central focus. A recent study published in the Morbidity and Mortality Weekly Report (MMWR) brings into light insights about the updated 2023-24 COVID-19 vaccine. The study aims at understanding the impact of the updated monovalent XBB.1.5 vaccine against symptomatic COVID-19 infection, including the new JN.1 lineage.
According to the study, the updated vaccine provides approximately 54% protection against symptomatic illness. The estimated vaccine effectiveness (VE) is 57% in the 18-49 age group and 46% among individuals aged 50 and older. The VE was also estimated at 58% and 49% among people tested 7-59 and 60-119 days after receiving the updated vaccine, respectively.
The primary focus of the study was to ascertain the effectiveness of the updated COVID-19 vaccine against symptomatic SARS-CoV-2 infection, including the JN.1 and other circulating lineages. The effectiveness of the vaccine against severe disease and its expected waning over time were also analyzed. The study found that the updated COVID-19 vaccines provide approximately 54% increased protection against symptomatic SARS-CoV-2 infection compared to no receipt of the updated vaccine.
However, its vital to note that the study suggests the VE will likely wane with time since vaccination, especially against less severe outcomes. This finding is consistent with other studies that show vaccine-induced immunity tends to decrease over time, necessitating regular updates to the vaccine and possible booster shots.
The findings of the study have important implications for public health and vaccine strategies. The CDCs Advisory Committee on Immunization Practices recommends that all persons aged 6 months and older should receive the updated COVID-19 vaccine. This recommendation is particularly crucial considering the introduction of new SARS-CoV-2 lineages and the potential for decreased vaccine effectiveness over time.
The MMWR study is one among many public health resources providing crucial information on topics such as asthma, travel-related diagnoses, e-cigarette sales, COVID-19 vaccine effectiveness, HIV behavioral surveillance among transgender women, and CDC guidelines for the prevention and treatment of anthrax. Such reports underline the importance of ongoing research and timely vaccination in managing the COVID-19 pandemic.
The updated 2023-24 COVID-19 vaccine shows promising effectiveness against symptomatic infection, including the JN.1 lineage. However, as with all vaccines, the effectiveness is expected to wane over time, underscoring the importance of staying updated with vaccinations. As research continues to evolve with the pandemic, it is crucial to rely on credible sources for information, like the MMWR, and follow recommended vaccination schedules to safeguard individual and public health.
In a recent modeling and meta-analysis study published in the journal Nature Communications, researchers evaluated if maternal immunization against pertussis, a highly contagious bacterial respiratory infection, experienced reduced efficacy (blunting) due to prolonged use. They reviewed four studies with up to six years of follow-up and designed a novel mathematical model to evaluate immunizations short- and long-term effects on disease transmission dynamics. While incapable of ruling out minor reductions in vaccine effectiveness (VE), their findings highlight that maternal immunizations are (and will continue to be) essential in preventing pertussis transmission and, more importantly, saving the lives of unvaccinated newborns.
Study: Maternal pertussis immunization and the blunting of routine vaccine effectiveness: a meta-analysis and modeling study. Image Credit:Kateryna Kon/ Shutterstock
Pertussis, colloquially called whooping cough, is a highly contagious respiratory illness caused by the bacteria Bordetella pertussis. Its symptoms included chronic or severe cough, general fatigue and fever, nausea, and difficulty breathing. It is characterized by its severe hacking cough from which the name whooping is obtained. Pertussis infections are most severe in children, especially newborns, and were a significant cause of childhood mortality before the 1940s.
Thankfully, pertussis is easily preventable via vaccines. Global large-scale immunization efforts in the 1940s reduced transmission rates by 90% in most countries. Unfortunately, for reasons hitherto unknown, pertussis has been staging a comeback over the past two decades. This has prompted a resurgence into pertussis-centric research aimed at evaluating the mechanisms underpinning rising transmission rates.
Infants, especially newborns, are the cohort most vulnerable to the disease, given their suboptimal immune development and lack of immunization. To counter this, numerous nations (since 2012) and the World Health Organization (since 2015) have recommended and initiated maternal immunization programs. Vaccinating women during the gestation period has been clinically revealed to transfer its protective effects to their unborn infants, resulting in an estimated 70% reduction in newborn mortality.
However, the downstream consequences of maternal immunization, when infants receive their routine pertussis vaccines, are poorly understood. Specifically, there has been long-standing concern regarding potential immunological blunting, i.e., the interference of maternally transferred antibodies with the infant immune response.
Understanding if current vaccination protocols are resulting in immunization blunting, and if so, to what extent, will allow for the revision of present immunization policies and may require an overhaul of the vaccines used or the process itself.
In the present study, researchers conducted a meta-analysis to investigate if prolonged (2012 to 2023) maternal immunization has reduced vaccine effectiveness (VE). The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
Data collection was initiated by collating relevant publications from three online databases (PubMed, Web of Science, and Scopus) from database initiation till August 25, 2023. This search revealed 374 articles across databases, 146 of which were duplicate records. Of the 228 remaining publications, abstract screening revealed 69 potential articles, which full-text screening further narrowed down to the final sample set four.
To be included in our review, studies had to provide an estimate of the relative risk (RR) of pertussis in infants having received at least one dose of their primary immunization from vaccinated vs. unvaccinated mothers. We selected only those studies that used laboratory-confirmed diagnosis of pertussis.
Each of the four included studies reported at least five pertussis relative risk estimates in comparing vaccinated and unvaccinated mothers. Study analyses were carried out using two steps Firstly, to account for different metrics used in the included studies, standard relative risks were calculated and applied to each included metric. Secondly, the meta-analyses were carried out. The meta-regression used herein was corrected to account for population as a random intercept.
Finally, researchers devised a novel mathematical model based on the Susceptible-Exposed-Infected-Recovery (SEIR) model, explicitly testing for VE accounting for immunization blunting. The model had two outcome measures 1. failure in take (if the primary vaccine failed), and 2. failure in duration (loss or reduction of vaccine protection). The model works in a hierarchical compartmentalization framework comprising three levels, each with their own paths.
Level 1: These three possible paths or compartments start from their mothers immunization status during pregnancy, followed by an infant immunization schedule that resembles that of the empirical studies. Level 2: newborns can be born in three possible compartments: from vaccinated mothers whose immunization succeeded, mothers whose immunization failed (i.e., who received the vaccine but whose infant remained unprotected), or unvaccinated mothers. Level 3: Each of the three compartments is followed by a compartment for successful primary infant immunization and a compartment for failed primary infant immunization, thereby becoming susceptible, or no immunization thereby also becoming susceptible.
Exploring the historical landscape of VE in infant pertussis via the novel model revealed that infant (maternal) immunization substantially decreased disease incidence. However, consistent with global reports, this was followed by a gradual rebound in pertussis persistence. This is consistent with the previously described end-of-honeymoon effect and is expected in most diseases managed using imperfect yet highly efficient vaccines. These results validate model reliability.
Analyzing the sample dataset using this model revealed that the first vaccine dose in infants following maternal immunization is highly effective against pertussis contraction, but the second and third doses are much more uncertain, consistent with previous uncertainty regarding blunting effects. The model demonstrated the presence of a decade-long lag phase following the introduction of maternal immunization, during which time blunting effects are liable to be underestimated in trial studies.
Encouragingly, quantifying the blunting effects suggests that they are minor and pale compared to the infant mortality-saving that maternal immunization provides. These findings support the public health decisions of many countries (55 as of 2021) to continue maternal immunization efforts and recommend that other nations follow suit.
The present study conducted a meta-regression analysis of four epidemiological publications to investigate the potential blunting effect of decade-long maternal immunization efforts. They further devised and implemented a mathematical model to interpret pertussis relative risk while explicitly accounting for vaccine efficacy blunting.
Their findings reveal the presence of a transient decade-long lag phase following maternal immunization, characterized by the masking and underestimation of blunting effects, thereby explaining previous inconsistencies in the literature. More importantly, the study highlights that while moderate levels of VE loss via blunting do exist, they are far outweighed by the infant mortality savings that maternal vaccination provides.
Journal reference:
Phase 3 Trial data results of The R21/Matrix-M vaccine developed by Oxford University and Serum Institute of India Pvt Ltd, leveraging Novavaxs Matrix-M adjuvant has confirmed high efficacy and supported regulatory approvals and licensure in several African countries. The R21/Matrix-M vaccine was designed in 2011 as a potential improvement on the RTS, S/AS01 malaria vaccine designed in the 1980s. A phase II trial in Burkina Faso, reporting in 2021, was the first to show that R21/Matrix-M could reach the WHO-specified target of 75% efficacy in African children. Recent WHO endorsement will lead to the initial rollout of R21/Matrix-M in the coming months. The new results are published inThe Lancettoday.
The trial investigators immunised over 4800 young children in a trial in Burkina Faso, Kenya, Mali and Tanzania and found on average 78% vaccine efficacy over the first year of follow-up across all sites in the 5-17-month-old age group, the age range group which is studied for most malaria vaccines. Efficacy over this period was broadly similar across sites and in different transmission settings. Safety data from the trial have been reassuring with no serious adverse events linked to immunisation. No other vaccine has reported over 55% efficacy in the same age group. A booster dose at a year maintained good efficacy over the following 6-12 months. The vaccine also reduced infection rates in children measured at 12 and 18 months after vaccination suggesting a potentially beneficial effect in reducing malaria transmission.
R21/Matrix-M vaccine was well tolerated, with injection site pain and fever as the most frequent adverse events. Number of adverse events of special interest and serious adverse events did not significantly differ between the vaccine groups. There were no treatment-related deaths.
Malaria is the largest cause of death in young African children with over 600,000 deaths globally each year. Two vaccines have recently achieved and completed World Health Organization (WHO) prequalification and initial deployments are starting early this year.
Professor Adrian Hill, chief investigator of the R21/Matrix-M phase 3 trial saidThe continued high efficacy of this new vaccine in field trials is very encouraging, and consistent with the high efficacy and excellent durability observed in a smaller four-year phase IIb trial. These data support an important role for the unique high-density nanoparticle display of the conserved repeat region of the malaria parasite circumsporozoite protein, a feature in the design of the R21 vaccine, in providing such high vaccine efficacy and, thereby, an important new tool for malaria control.
Significantly increased immune responses to the R21/Matrix-M vaccine and slightly higher vaccine efficacy were observed in 5-17-month-olds compared to 18-36-month-olds malaria vaccines, supporting planned vaccine deployment initially from 5 months of age in young African children.
The vaccine is licensed to the Serum Institute of India (SII), the worlds largest vaccine manufacturer and a long-term partner of the University of Oxford. This is critical because vaccinating those at high risk of malaria will be important in stemming the spread of the disease, as well as protecting the vaccinated. Matrix-M adjuvant is manufactured by Novavax AB and provided to Serum Institute of India for formulation into the final vaccine drug product.
Adar Poonawalla, CEO, Serum Institute of India, said,"The Lancet study on R21/Matrix-M Phase 3 trials mark a significant advancement in our battle against this global threat. Our collaboration with the University of Oxford has been instrumental in developing the R21/Matrix-M malaria vaccine. We are dedicated to making this vaccine available, especially in Africa, where malaria poses a substantial threat to millions of lives, bringing us closer to a malaria-free world."
Professor Alassane Dicko, Principal Investigator in Mali of the R21/Matrix-M vaccine saidIt has been very exciting to generate high efficacy data with the new R21/Matrix-M vaccine so quickly. I predict that this vaccine should be very impactful in preventing malaria deaths in African children.
John C Jacobs, CEO of Novavax commentedApproximately 1,300 children die from malaria every day, a staggering statistic for a preventable disease. The R21/Matrix-M Phase 3 efficacy data published in The Lancet reinforce the potential of R21/Matrix-M vaccine to protect children against this disease. We are proud of the role of Novavax's patented saponin-based Matrix-M adjuvant, which has been demonstrated to enhance the immune response, in the outcome of this clinical trial and are eager to see the realized impact of the vaccine when it is rolled out globally.
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In a recent study published in Morbidity and Mortality Weekly Report, researchers estimated the effectiveness of the 2023-24 updated coronavirus disease 2019 (COVID-19) vaccine.
The Advisory Committee on the Immunization Practices of the United States (US) Centers for Disease Control and Prevention (CDC) recommended on September 12, 2023, that all individuals aged six months or older receive the 2023-24 updated monovalent COVID-19 vaccine. The updated vaccine contains a component from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron XBB.1.5 lineage and lacks ancestral strain components.
The JN.1 lineage was identified in the US in September 2023, which harbors 30 additional mutations in the spike (S) protein compared to XBB.1.5. Real-time reverse-transcription polymerase chain reaction (RT-PCR) results can help distinguish some SARS-CoV-2 lineages. S-gene target failure (SGTF) is detected in JN.1 and other BA.2.86 lineages, whereas S-gene target presence (SGTP) is detected in most lineages from 2023, including XBB.
Study: Early Estimates of Updated 20232024 (Monovalent XBB.1.5) COVID-19 Vaccine Effectiveness Against Symptomatic SARS-CoV-2 Infection Attributable to Co-Circulating Omicron Variants Among Immunocompetent Adults Increasing Community Access to Testing Program, United States, September 2023January 2024. Image Credit:New Africa/ Shutterstock
In the present study, researchers estimated the effectiveness of the 2023-24 updated COVID-19 vaccine against symptomatic infection. They included tests conducted between September 21, 2023, and January 14, 2024, among adults reporting at least one symptom. Cases were individuals with a positive nucleic acid amplification test (NAAT).
Controls were individuals with a negative NAAT. The team excluded tests from Janssen vaccine recipients, Novavax recipients, immunocompromised individuals, those who received the most recent vaccine dose within a week preceding testing, and those with a positive COVID-19 test within the past 90 days.
Vaccine effectiveness (VE) against symptomatic COVID-19 was estimated by comparing the odds of receipt of the updated vaccine versus non-receipt among cases and controls. Multivariable logistic regression was used to estimate odds ratios. VE was computed separately by SGTP and SGTF status. Test-positive samples with reduced or null S-gene amplification were deemed to have an SGTF, whereas those without SGTF were considered SGTP.
Of over 9,200 NAAT results for individuals with symptoms of COVID-19-like illness, 3,295 tested SARS-CoV-2-positive. Around 1,125 individuals received the updated COVID-19 vaccine seven days earlier. More controls received the updated vaccine than cases. The median time from the last dose among updated vaccine recipients was 60 days for cases and 51 days for controls.
Nearly 8,100 individuals did not receive the updated vaccine. Of these, 30% were non-vaccinated and 70% were vaccinated. Among the vaccinated, the median time since vaccination was 378 days for cases and 363 days for controls. The estimated VE was 57% in the 1849 age group and 46% among those aged 50. VE was estimated at 58% and 49% among people tested 759 and 60119 days after receiving the updated vaccine, respectively.
There were 679 tests available with S-gene target results. Of these, 258 showed SGTF, and 421 exhibited SGTP. VE was not precise for tests with SGTF during the 759 days post-receipt of the updated vaccine, given the emergence of JN.1 in the US. VE during the 60119 days post-receipt of the updated vaccine was 60% for tests with SGTP and 49% for those with SGTF.
The study provided early efficacy estimates of the updated monovalent XBB.1.5 vaccine against symptomatic infection and the first VE estimates against the JN.1 lineage. These VE estimates include data up to 119 days post-vaccination. However, VE will likely wane with time since vaccination, as observed after the original monovalent or bivalent COVID-19 vaccination. Prior infection history, medical conditions, and vaccination status were self-reported, thereby subject to recall bias.
Besides, the VE estimates were computed for a population that opted to be tested for COVID-19; therefore, the estimates are subject to selection biases. Further, coverage of the updated vaccine is low among adults and varies by age. Taken together, the updated monovalent vaccine provided 54% protection from symptomatic illness. Waning of the VE is expected over time, especially against less severe outcomes.
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