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Vaccine Sep 2023From 2008 to 2019, France has experienced a resurgence of measles epidemics. Surveillance data have shown that the proportion of cases vaccinated with two doses of... (Observational Study)
Observational Study
BACKGROUND
From 2008 to 2019, France has experienced a resurgence of measles epidemics. Surveillance data have shown that the proportion of cases vaccinated with two doses of measles-containing vaccine (MCV) increased with age, raising concerns about the duration of vaccine protection. Our objectives were to investigate age-stratified vaccine effectiveness (VE) for the second dose of MCV (MCV2) and to quantify protection levels over time.
METHODS
We analyzed data on measles cases aged 2-31 years, reported via mandatory notification to the French measles surveillance system from October 2017 to September 2019. We estimated an age-stratified VE for MCV2 using the screening method, which compares the vaccination status of cases with that of the general population. We improved this method by accounting for natural immunity, exploring four scenarios with four possible levels of natural immunity in the population. In addition, we quantified the decay rate of protection over time, by fitting an exponential decay model among individuals vaccinated in early life.
RESULTS
In the baseline analysis (absence of natural immunity), VE estimates were high in all age groups and decreased with age, from 99.6 % (95 % confidence interval: 99.3-99.8) in 2-5 years old to 91.4 % (85.1-95.0) in 26-31 years old. Accounting for natural immunity increased VE in the older age group to 93.2-99.2 % depending on the scenario. We estimated that VE was slowly decreasing over time, with an exponential decay rate of 0.0022/year (0.0017-0.0028), leading to VE of 96.7 % (96.0-97.4) 16 years after MCV2 vaccination. This decline was most compatible with scenario 2, a scenario of 4.4 % naturally immunized, non-vaccinated individuals in the 26-31 years old.
CONCLUSION
Our study confirms the continued high effectiveness of two doses of MCV with only slight degradation, decades after immunization. These findings support the importance of achieving a very high vaccination coverage with 2 doses of MCV.
Topics: Humans; Aged; Child, Preschool; Adult; Measles Vaccine; Vaccine Efficacy; Measles; Epidemics; France
PubMed: 37586955
DOI: 10.1016/j.vaccine.2023.08.018 -
Nature Medicine Aug 2019
Topics: Humans; Immunity, Herd; Measles; Measles Vaccine; Public Health; Vaccination
PubMed: 31227810
DOI: 10.1038/s41591-019-0515-2 -
Human Vaccines & Immunotherapeutics Nov 2022Nigeria has one of the highest measles burdens in the world. While measles-containing vaccine is proven to be effective in reducing measles cases, empirical studies on... (Observational Study)
Observational Study
Nigeria has one of the highest measles burdens in the world. While measles-containing vaccine is proven to be effective in reducing measles cases, empirical studies on the correlation between measles incidence and measles vaccine coverage in Nigeria has been limited. The aim of this study was to conduct a detailed analysis on measles incidence, measles vaccine coverage, and their correlation between 2012 and 2021. A retrospective observational study was conducted based on the Integrated Disease Surveillance and Response (IDSR) data for the measles incidence in each Nigerian state over time, District Health Information System, V.2 (DHIS2) and Nigeria Demographic and Health Survey (DHS) for the coverage of the first dose of measles containing vaccine (MCV1) over time (2012-2021). We observed the trend of measles incidence and measles vaccine coverage, as well as their correlation. Out of the study period from 2012 to 2021, we found that the majority of measles outbreaks occurred in the northeastern states in recent years after 2019, especially in Borno state, where Boko Haram insurgency has negatively impacted health service delivery, including routine vaccination. We observed a significant negative correlation between measles incidence and measles vaccine coverage across Nigerian states. However, there was no sudden drop in measles vaccine coverage before the recent outbreak in Borno state in 2019, which could be due to various factors other than the overall vaccine coverage.
Topics: Humans; Infant; Measles; Measles Vaccine; Vaccination Coverage; Vaccination; Disease Outbreaks; Incidence; Nigeria
PubMed: 36041074
DOI: 10.1080/21645515.2022.2114697 -
Lancet (London, England) May 2024Microneedle patches (MNPs) have been ranked as the highest global priority innovation for overcoming immunisation barriers in low-income and middle-income countries.... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Microneedle patches (MNPs) have been ranked as the highest global priority innovation for overcoming immunisation barriers in low-income and middle-income countries. This trial aimed to provide the first data on the tolerability, safety, and immunogenicity of a measles and rubella vaccine (MRV)-MNP in children.
METHODS
This single-centre, phase 1/2, double-blind, double-dummy, randomised, active-controlled, age de-escalation trial was conducted in The Gambia. To be eligible, all participants had to be healthy according to prespecified criteria, aged 18-40 years for the adult cohort, 15-18 months for toddlers, or 9-10 months for infants, and to be available for visits throughout the follow-up period. The three age cohorts were randomly assigned in a 2:1 ratio (adults) or 1:1 ratio (toddlers and infants) to receive either an MRV-MNP (Micron Biomedical, Atlanta, GA, USA) and a placebo (0·9% sodium chloride) subcutaneous injection, or a placebo-MNP and an MRV subcutaneous injection (MRV-SC; Serum Institute of India, Pune, India). Unmasked staff ransomly assigned the participants using an online application, and they prepared visually identical preparations of the MRV-MNP or placebo-MNP and MRV-SC or placebo-SC, but were not involved in collecting endpoint data. Staff administering the study interventions, participants, parents, and study staff assessing trial endpoints were masked to treatment allocation. The safety population consists of all vaccinated participants, and analysis was conducted according to route of MRV administration, irrespective of subsequent protocol deviations. The immunogenicity population consisted of all vaccinated participants who had a baseline and day 42 visit result available, and who had no protocol deviations considered to substantially affect the immunogenicity endpoints. Solicited local and systemic adverse events were collected for 14 days following vaccination. Unsolicited adverse events were collected to day 180. Age de-escalation between cohorts was based on the review of the safety data to day 14 by an independent data monitoring committee. Serum neutralising antibodies to measles and rubella were measured at baseline, day 42, and day 180. Analysis was descriptive and included safety events, seroprotection and seroconversion rates, and geometric mean antibody concentrations. The trial was registered with the Pan African Clinical Trials Registry PACTR202008836432905, and is complete.
FINDINGS
Recruitment took place between May 18, 2021, and May 27, 2022. 45 adults, 120 toddlers, and 120 infants were randomly allocated and vaccinated. There were no safety concerns in the first 14 days following vaccination in either adults or toddlers, and age de-escalation proceeded accordingly. In infants, 93% (52/56; 95% CI 83·0-97·2) seroconverted to measles and 100% (58/58; 93·8-100) seroconverted to rubella following MRV-MNP administration, while 90% (52/58; 79·2-95·2) and 100% (59/59; 93·9-100) seroconverted to measles and rubella respectively, following MRV-SC. Induration at the MRV-MNP application site was the most frequent local reaction occurring in 46 (77%) of 60 toddlers and 39 (65%) of 60 infants. Related unsolicited adverse events, most commonly discolouration at the application site, were reported in 35 (58%) of 60 toddlers and 57 (95%) of 60 infants that had received the MRV-MNP. All local reactions were mild. There were no related severe or serious adverse events.
INTERPRETATION
The safety and immunogenicity data support the accelerated development of the MRV-MNP.
FUNDING
Bill & Melinda Gates Foundation.
Topics: Humans; Double-Blind Method; Gambia; Female; Male; Rubella Vaccine; Infant; Measles Vaccine; Adult; Adolescent; Rubella; Young Adult; Measles; Needles; Antibodies, Viral
PubMed: 38697170
DOI: 10.1016/S0140-6736(24)00532-4 -
Journal of Medical Virology Feb 2022In 2017, the Regional Verification Commission for Measles and Rubella Elimination (RVC) of the World Health Organization confirmed that measles elimination was sustained...
In 2017, the Regional Verification Commission for Measles and Rubella Elimination (RVC) of the World Health Organization confirmed that measles elimination was sustained in Montenegro, and the previous endemic transmission remained interrupted. However, the RVC was extremely concerned over the continuing low vaccination coverage reported for this country. In this study, we describe the most recent measles epidemic in Montenegro using the epidemiological data collected from January 1 to July 31, 2018. The outbreak is largely attributable to a dangerous accumulation of susceptible subjects across the country and represents a high-risk factor for re-establishing endemic transmission in the Balkan area. This study showed how a vaccine-preventable communicable disease outbreak can have a dramatic impact and severe consequences on regional public health system performance in terms of the sanitary spending point of view. A detailed update is provided on the epidemiological situation in this Central European area, not available until now.
Topics: Adolescent; Adult; Child; Child, Preschool; Disease Eradication; Disease Outbreaks; Female; Humans; Infant; Logistic Models; Male; Measles; Measles Vaccine; Montenegro; Risk Factors; Vaccination Coverage; Young Adult
PubMed: 34617629
DOI: 10.1002/jmv.27377 -
The Journal of Infectious Diseases Sep 2021In 2019, the United States (US) experienced the highest number of measles importations and cases in the postelimination era. More than a quarter of imported cases...
In 2019, the United States (US) experienced the highest number of measles importations and cases in the postelimination era. More than a quarter of imported cases entered the US through California. Measles surveillance efforts in California resulted in the identification of 26 importations, 6 outbreaks, and 72 cases in 2019. Only genotype B3 and D8 measles strains were detected. Genotype-specific differences were noted in the incidence of vaccine failures, hospitalizations, and severe complications among cases. A targeted whole genome sequencing approach provided higher-resolution discrimination between epidemiologically linked and sporadically introduced strains than conventional N450 sequencing. Our report underscores the importance of ensuring appropriate measles vaccination status, especially prior to international travel to measles-endemic regions, and highlights the value of a strong measles surveillance system in minimizing outbreaks and preserving measles elimination status in the US.
Topics: Adolescent; Adult; Aged; California; Child; DNA-Directed RNA Polymerases; Disease Outbreaks; Female; Genotype; Humans; Male; Measles; Measles Vaccine; Measles virus; Middle Aged; Molecular Epidemiology; Phylogeny; Sequence Analysis, DNA; United States; Young Adult
PubMed: 33528506
DOI: 10.1093/infdis/jiab059 -
Mayo Clinic Proceedings Aug 2020In addition to the vaccines due in the first year of life, the US Advisory Committee on Immunization Practices recommends that children continue to receive vaccines... (Review)
Review
In addition to the vaccines due in the first year of life, the US Advisory Committee on Immunization Practices recommends that children continue to receive vaccines regularly against a variety of infectious diseases. Starting at 12 to 15 months of life, these include the two-dose measles-mumps-rubella vaccine series and the two-dose varicella vaccine series. Also in the second year of life, infants should begin the two-dose hepatitis A vaccine series and complete the Haemophilus influenzae type B vaccine series as well as the pneumococcal conjugate vaccine series. Before 19 months of life, infants should receive the third dose of the poliovirus vaccine and the fourth dose of diphtheria-tetanus-acellular pertussis (DTaP) vaccine. The final doses of poliovirus and tetanus-diphtheria-acellular pertussis vaccines are both due at 4 to 6 years of life. Before each influenza season, every child should receive the influenza vaccine. Those less than 9 years of age who previously received less than two doses need two doses a month apart. At 11 to 12 years of life, all should get two doses of the human papillomavirus vaccine, the adolescent/adult version of the tetanus-diphtheria-acellular pertussis vaccine, and begin a two-dose series of meningococcal ACWY vaccine. Each of these vaccines is due when the vaccine works to protect against both an immediate risk as well as to provide long-term protection. Each vaccine-preventable disease varies in terms of the nature of exposure, the form of the morbidity, the risk of mortality, and potential to prevent or ameliorate its harm.
Topics: Adolescent; Age Factors; Chickenpox Vaccine; Child; Child, Preschool; Diphtheria-Tetanus-Pertussis Vaccine; Female; Hepatitis A Vaccines; Humans; Infant; Influenza Vaccines; Male; Measles Vaccine; Meningococcal Vaccines; Mumps Vaccine; Papillomavirus Vaccines; Rubella Vaccine; Sex Factors; Vaccines
PubMed: 32753151
DOI: 10.1016/j.mayocp.2020.06.004 -
Vaccine May 2021In North America, the first dose of a measles-containing vaccine (MCV1) is administered at ≥12 months of age. However, MCV1 may be given to infants <12 months living... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
In North America, the first dose of a measles-containing vaccine (MCV1) is administered at ≥12 months of age. However, MCV1 may be given to infants <12 months living in highly endemic areas or traveling to these areas. Although an early dose of MCV1 leads to immediate protection, it remains unclear how this impacts long-term immunity.
METHODS
This systematic review and meta-analysis evaluates the impact of MCV1 given at <12 months vs. ≥12 months of age on long-term immunogenicity and vaccine effectiveness, with long-term defined as at least one-year post-vaccination. PubMed, EMBASE, Global Health, Web of Science and Scopus were searched on October 31st, 2019. Studies were included if they included a cohort of infants vaccinated <12 months of age and evaluated long-term immunogenicity, vaccine efficacy, or effectiveness.
RESULTS
A total of 51 texts were identified: 23 reported outcomes related to vaccine effectiveness and 30 to immunogenicity. Infants vaccinated with MCV1 < 12 months of age showed an overall higher risk of measles compared to ≥12 months of age (RR = 3.16, 95% CI: 2.00, 5.01; OR = 2.46, 95% CI: 1.40, 4.32). Risk of measles decreased with increasing age at first vaccination, with those vaccinated with one dose ≥15 months at a lesser risk compared to 12-14 months or <12 months. Measles seroconversion and seropositivity was not affected by age at first vaccination, but antibody levels were significantly lower in the MCV1 < 12-month group (MD = -0.40, 95% CI: -0.71, -0.09).
CONCLUSION
Long-term measles seroconversion and seropositivity did not appear to be affected by age at MCV1, while vaccine effectiveness decreased with younger age. There was not enough evidence to look at the effect of age at MCV1 on immune blunting.
Topics: Antibodies, Viral; Humans; Immunization Schedule; Infant; Measles; Measles Vaccine; Measles virus; North America; Vaccination
PubMed: 33926750
DOI: 10.1016/j.vaccine.2021.04.012 -
The Pan African Medical Journal 2020In October 4, 2018, a measles outbreak was declared in Madagascar. This study describes the epidemiology of the outbreak and determines public health implications for...
INTRODUCTION
In October 4, 2018, a measles outbreak was declared in Madagascar. This study describes the epidemiology of the outbreak and determines public health implications for measles elimination in Madagascar.
METHODS
Data have been collected using line list developed for the outbreak. Serum samples were collected within 30 days of rash onset for laboratory testing; confirmation was made by detection of measles immunoglobulin M (IgM) antibody.
RESULTS
A total of 2,930 samples were analysed in the laboratory among which 1,086 (37%) were laboratory confirmed. Measles cases age ranged from a minimum of 1 month to a maximum of 88 years. The median and the mean were 7 years and 9 years respectively. Children between 1 to 9 years accounted for 50.6% of measles cases. Attack rate (39,014 per 1,000,000 inhabitants) and case fatality rate (1.2%) were highest among children aged 9-11 months. A total of 67.2% cases were unvaccinated. As of March 14, 2019, all the 22 regions and 105 (92%) health districts out of 114 were affected by the measles outbreak in Madagascar.
CONCLUSION
Measles outbreak in Madagascar showed that the country is not on the track to achieve the goal of measles elimination by 2020.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Disease Outbreaks; Female; Humans; Immunoglobulin M; Infant; Madagascar; Male; Measles; Measles Vaccine; Middle Aged; Public Health; Young Adult
PubMed: 32537087
DOI: 10.11604/pamj.2020.35.84.19630 -
Human Vaccines & Immunotherapeutics May 2020Today, the United States and countries throughout the world are experiencing measles outbreaks that have sickened thousands of children. From the Disneyland outbreak in...
Today, the United States and countries throughout the world are experiencing measles outbreaks that have sickened thousands of children. From the Disneyland outbreak in 2014 to today, some states have responded with changes in laws on vaccine requirements and exemptions. In this article, we examine the history of vaccine laws, and using our 2015 survey data, explore to what extent the news coverage of the Disneyland outbreak altered parents' attitudes toward required vaccination and non-medical exemptions. We explore those results in the context of today's increasing polarized and politicalized battle over vaccine laws, and consider how health care providers and policy makers can work to improve public attitudes about vaccines.
Topics: Attitude; Child; Disease Outbreaks; Humans; Measles; Measles Vaccine; Parents; United States; Vaccination; Vaccines
PubMed: 31403354
DOI: 10.1080/21645515.2019.1646578