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Rubella virus is a leading cause of vaccine-preventable birth defects. Infection during pregnancy can result in miscarriage, fetal death, stillbirth or a constellation of birth defects, known as congenital rubella syndrome (CRS), which includes cataracts, deafness, heart defects and developmental delay. A single dose of rubella-containing vaccine can provide lifelong protection against rubella. The Global Vaccine Action Plan 2011-2020 set a target to achieve elimination of rubella in at least 5 of the 6 WHO regions by 2020, and rubella elimination is a critical goal of the Immunization Agenda 2030. This report updates a previous report and describes progress towards rubella and CRS elimination in 2012-2022. During this period, the number of WHO Member States that included rubella-containing vaccine (RCV) in their immunization schedules increased from 132 (68%) to 175 (90%), and the percentage of the world's infants were vaccinated against rubella increased from 40% to 68%. The reported number of rubella cases decreased by 81%, from 93 816 in 2012 to 17 407 in 2022. Verification of rubella elimination was achieved in 98 (51%) of 194 countries by 2022, an increase from 84 (43%) countries in 2019. Despite significant progress in introduction of RCV into routine immunization programmes worldwide, nearly 25 million infants annually still do not receive RCV. Nevertheless, the increasing number of countries that have achieved and sustained rubella elimination, even in complex settings, represents progress towards global rubella elimination. L'infection par le virus de la rubeole est l'une des principales causes de malformations congenitales evitables par la vaccination. Lorsqu'elle survient pendant la grossesse, elle peut entrainer une fausse couche, la mort foetale, une mortinaissance ou une constellation de malformations congenitales (notamment cataracte, surdite, malformations cardiaques et retards de developpement) connue sous le nom de syndrome de rubeole congenitale (SRC). Une dose unique de vaccin a valence rubeole peut conferer une protection a vie contre la rubeole. Parmi les cibles fixees dans le Plan d'action mondial pour les vaccins 2011-2020 figurait l'elimination de la rubeole dans au moins 5 des 6 Regions de l'OMS a l'horizon 2020. L'elimination de la rubeole fait en outre partie des objectifs cles du Programme pour la vaccination a l'horizon 2030. Le present rapport actualise les informations fournies dans le rapport precedent et decrit les progres accomplis vers l'elimination de la rubeole et du SRC dans la periode 2012-2022. Au cours de cette periode, les nombre d'Etats Membres de l'OMS ayant inclus le vaccin a valence rubeole (RCV) dans leur calendrier de vaccination a progresse, passant de 132 (68%) a 175 (90%); et le pourcentage de nourrissons dans le monde vaccines contre la rubeole est passe de 40% a 68%. Le nombre de cas notifies de rubeole a recule de 81%, passant de 93 816 en 2012 a 17 407 en 2022. En 2022, l'elimination de la rubeole avait ete verifiee dans 98 (51%) des 194 Etats Membres de l'OMS, contre 84(43%) en 2019. Toutefois, meme si l'introduction du RCV dans les programmes de vaccination systematique a fortement progresse a l'echelle mondiale, pres de 25millions de nourrissons sont encore prives de ce vaccin chaque annee. Le nombre croissant de pays ayant reussi a eliminer durablement la rubeole, meme parmi ceux confrontes a des situations complexes, temoigne neanmoins des progres realises vers l'elimination de cette maladie a l'echelle mondiale., Introduction Rubella virus is a leading cause of vaccine-preventable birth defects and can cause epidemics. Rubella virus infection usually produces a mild febrile rash illness in children and adults; however, [...]

Measles is a highly contagious, vaccine-preventable disease that requires high population immunity in order for transmission to be interrupted. All 6 WHO regions have committed themselves to eliminating measles; however, no region has achieved and sustained elimination. This report describes progress in measles elimination during 2000-2022. Estimated coverage with the first dose of measles-containing vaccine (MCV) worldwide increased from 72% to 86% between 2000 and 2019 and then decreased to 81% in 2021 during the coronavirus disease 2019 (COVID-19) pandemic, the lowest coverage rate since 2008. In 2022, MCV1 coverage increased to 83%. Only 72 (50%) of 144 countries that reported measles cases achieved the measles surveillance indicator target of >2 discarded cases per 100 000 population in 2022. During 2021-2022, estimated measles cases increased by 18%, from 7 802 000 to 9 232 300, and the number of countries experiencing large or disruptive outbreaks increased from 22 to 37. The estimated number of measles deaths increased by 43% during 2021-2022, from 95 000 to 136 200. Nonetheless, an estimated 57 million measles deaths were averted by vaccination during 2000-2022. In 2022, measles vaccination coverage and global surveillance showed some recovery from the setbacks during the COVID-19 pandemic; however, coverage decreased in low-income countries, and, globally, years of suboptimal immunization coverage left millions of children unprotected. Setbacks in coverage during the COVID-19 pandemic must be reversed by renewed efforts to vaccinate all children with 2 MCV doses, strengthen surveillance, prevent outbreaks and accelerate progress towards elimination. La rougeole est une maladie a prevention vaccinale qui est hautement contagieuse et dont la transmission ne peut etre interrompue qu'en presence d'une forte immunite collective. Les 6 Regions de l'OMS se sont toutes engagees a eliminer la rougeole, mais a ce jour, aucune d'entre elles n'a atteint durablement cet objectif. Le present rapport decrit les progres accomplis vers l'elimination de la rougeole au cours de la periode 2000-2022. La couverture mondiale de la vaccination par la premiere dose de vaccin a valence rougeole (MCV) a progresse entre 2000 et 2019, passant de 72% a 86%, mais a ensuite recule pendant la pandemie de COVID-19 pour s'etablir a 81% en 2021, soit le taux le plus faible enregistre depuis 2008. En 2022, la couverture par le MCV1 est remontee a 83%. En 2022, seuls 72 (50%) des 144 pays ayant signale des cas de rougeole ont atteint la cible de l'indicateur de surveillance de la rougeole relatif au nombre de cas ecartes, a savoir >2 cas ecartes pour 100 000 habitants. Dans la periode 2021-2022, le nombre de cas de rougeole signales a augmente de 18%, passant de 7 802 000 a 9 232 300, et, le nombre de pays confrontes a des flambees epidemiques de grande ampleur ou perturbatrices de rougeole est passe de 22 a 37, et le nombre estime de deces dus a la rougeole a augmente de 43%, passant de 95 000 a 136 200. Neanmoins, on estime qu'entre 2000 et 2022, la vaccination a permis d'eviter 57 millions de deces dus a la rougeole. En 2022, on a constate des signes de relevement de la couverture vaccinale et de la surveillance mondiale de la rougeole apres les revers subis lors de la pandemie de COVID-19; la couverture vaccinale a toutefois diminuee dans les pays a faible revenu et, apres des annees de couverture sousoptimale, des millions d'enfants dans le monde restent sans protection contre la maladie. Il est urgent d'inverser le recul de la couverture enregistre pendant la pandemie de COVID-19 en redoublant d'efforts pour vacciner tous les enfants par 2 doses de MCV, renforcer la surveillance, prevenir les flambees epidemiques et accelerer les progres vers l'elimination., Introduction All 6 WHO regions have committed themselves to eliminating measles. (1) The Immunization Agenda 2030 (IA2030) 2 includes measles elimination as a core indicator of impact. IA2030 highlights the [...]

In 2013, the 11 Member States of the WHO South-East Asia Region (1) (SEAR) adopted the goals of measles elimination and control of rubella and congenital rubella syndrome (CRS) (2) [...]

Measles vaccination effectively prevents measles, a highly contagious disease that can cause severe complications and death and requires high population immunity to interrupt transmission. This report describes measles elimination progress during 2000-2023. During 2000-2023, an estimated 60.3 million measles deaths were averted by vaccination. However, despite commitment from all six World Health Organization regions to eliminate measles, no region has successfully achieved and maintained measles elimination as of the end of 2023. During the COVID-19 pandemic, estimated global coverage with the first dose of measles-containing vaccine (MCV1) declined to 81%, the lowest level since 2008. MCV1 coverage improved to 83% in 2022 but was unchanged in 2023. From 2022 to 2023, estimated measles cases increased 20% worldwide, from 8,645,000 to 10,341,000; the number of countries experiencing large or disruptive outbreaks increased from 36 to 57. Estimated measles deaths decreased 8%, from 116,800 in 2022 to 107,500 in 2023, primarily because an increased number of cases occurred in countries with lower risk for death. The stagnation in MCV1 coverage means millions of children remain unprotected, leading to increases in cases and outbreaks. Coverage with measles-containing vaccine (MCV) is lower, and measles incidence is higher, in low-income countries and countries experiencing fragile, conflict-affected, and vulnerable settings, which exacerbate inequities. Urgent and targeted efforts are needed to ensure that all children receive 2 MCV doses and that surveillance is strengthened to hasten progress toward measles elimination. [ABSTRACT FROM AUTHOR]

In 2012, the World Health Assembly (WHA) endorsed the Global Vaccine Action Plan (GVAP), (1) with the objective of eliminating measles (2) in 5 of the 6 WHO regions by [...]

Introduction: The incidence of varicella in Canada has decreased by almost 99% since vaccination was introduced. However, variation in the timing and eligibility of vaccination programs across the country has resulted in some cohorts being under-vaccinated and therefore potentially susceptible to infection. Methods: We used nationally representative specimens from the Biobank of Statistics Canada's Canadian Health Measures Survey (CHMS) as well as residual specimens from Ontario collected between 2009–2014 to estimate population immunity across age-groups and geography, and identify any groups at increased risk of varicella infection. Results: The weighted proportion of specimens with antibody levels above the threshold of protection was 93.6% (95% CI: 92.4, 95.0). Protection was lowest among those aged 3–5 years (54.3%; 95% CI: 47.3, 61.4), but increased with age. Individuals born outside Canada had more than twice the odds of varicella susceptibility than those born in Canada (aOR: 2.7; 95% CI: 1.4, 5.0; p = 0.004). There were no differences by sex or geography within Canada, and there were no statistically significant differences when Ontario CHMS sera were compared to Ontario residual sera, apart from in participants aged 12–19 year age-group, for whom the CHMS estimate (91.2%; 95% CI: 86.7, 95.7) was significantly higher (p = 0.03) than that from residual specimens (85.9%, 95% CI: 81.1, 90.8). Discussion: Varicella immunity in Canada is changing. Children appear to have low population immunity, placing them at greater risk of infection and at increased risk of severe disease as they age. Our results underscore the importance of performing periodic serosurveys to monitor further population immunity changes as the proportion of vaccine-eligible birth-cohorts increases, and to continually assess the risk of outbreaks. [ABSTRACT FROM AUTHOR]

Since the World Health Assembly (WHA) in 2012 endorsed the Global Vaccine Action Plan (GVAP), which included regional measles and rubella elimination goals by 2020, global progress towards verification of measles and rubella elimination has been incremental. Even though the 2020 elimination goals were not achieved, commitment towards achieving measles and rubella elimination has been firmly established in the Immunization Agenda 2030 (IA2030) and the Measles and Rubella Strategic Framework (MRSF) 2021–2030. In 2023, the six Regional Verification Commissions for measles and rubella elimination (RVCs) reviewed data as of 31 December 2022 and confirmed that 82 (42%) Member States have been verified for measles elimination, and 98 (51%) Member States have been verified for rubella elimination. The six RVCs are composed of independent public health and immunization experts who are well-placed to support accelerating measles and rubella elimination. RVCs should be leveraged not only to review elimination documents but also to advocate for and champion public health programming that supports measles and rubella activities. The verification of elimination process is one of many tools that should be deployed to reinforce and accelerate efforts towards achieving a world free of measles and rubella. [ABSTRACT FROM AUTHOR]

Background Randomized trials conducted in low- and middle-income settings demonstrated efficacy of influenza vaccination during pregnancy against influenza infection among infants <6 months of age. However, vaccine effectiveness (VE) estimates from settings with different population characteristics and influenza seasonality remain limited. Methods We conducted a test-negative study in Ontario, Canada. All influenza virus tests among infants <6 months from 2010 to 2019 were identified and linked with health databases to ascertain information on maternal-infant dyads. VE was estimated from the odds ratio for influenza vaccination during pregnancy among cases versus controls, computed using logistic regression with adjustment for potential confounders. Results Among 23 806 infants tested for influenza, 1783 (7.5%) were positive and 1708 (7.2%) were born to mothers vaccinated against influenza during pregnancy. VE against laboratory-confirmed infant influenza infection was 64% (95% confidence interval [CI], 50%–74%). VE was similar by trimester of vaccination (first/second, 66% [95% CI, 40%–80%]; third, 63% [95% CI, 46%–74%]), infant age at testing (0 to <2 months, 63% [95% CI, 46%–75%]; 2 to <6 months, 64% [95% CI, 36%–79%]), and gestational age at birth (≥37 weeks, 64% [95% CI, 50%–75%]; < 37 weeks, 61% [95% CI, 4%–86%]). VE against influenza hospitalization was 67% (95% CI, 50%–78%). Conclusions Influenza vaccination during pregnancy offers effective protection to infants <6 months, for whom vaccines are not currently available. [ABSTRACT FROM AUTHOR]

Measles is a highly infectious disease leading to high morbidity and mortality impacting people's lives and economies across the globe. The measles vaccine saves more lives than any other vaccine in the Essential Programme of Immunization and is also the most cost-effective vaccine, with an extremely high return on investment. This makes achieving measles elimination through vaccination a key child health intervention, particularly in low-income countries, where the overwhelming majority of measles deaths continue to occur. All countries and regions of the world have committed to achieving measles elimination, yet many have faced challenges securing political commitment at national and global levels and predictable, timely, and flexible support from global donors, and experienced setbacks during the COVID-19 pandemic. This has happened against a backdrop of stagnant measles vaccination coverage and declining enthusiasm for vertical programmes, culminating in a World Health Organization Strategic Advisory Group of Experts (WHO SAGE) review of the feasibility of measles eradication in 2019. Sustaining the elimination of measles long term is extremely difficult, and some countries have lost or nearly lost their measles elimination status in the face of ongoing importation of cases from neighbouring or closely connected countries in which elimination had been delayed. Thus, a widening equity gap in measles immunisation coverage creates challenges for all countries, not just those facing the greatest burden of measles morbidity and mortality. Delaying elimination of measles in some countries makes it cumulatively harder for all countries to succeed for three principal reasons: increased inequity in measles immunisation coverage makes outbreaks more likely to happen and to be larger; political will is very difficult to sustain; and immunity may wane to a point that transmission is re-established. New strategies are needed to support countries and regions in their vision for a world without measles, including ways to galvanise domestic, regional and global resources and ignite the political will that is essential to make the vision a reality. [ABSTRACT FROM AUTHOR]

In 2010, the World Health Assembly (WHA) set the following 3 milestones for measles control to be achieved by 2015: 1) increase routine coverage with the first dose of measles-containing [...]

Because of the rapid growth of air travel and immigration, more travelers worldwide are exposed to nonendemic infectious diseases (e.g., Zika, measles, malaria) than ever before (1-3). In Ontario, Canada, [...]

An underestimation of pertussis burden has impeded understanding of transmission and disallows effective policy and prevention to be prioritized and enacted. Capture-recapture analyses can improve burden estimates; however, uncertainty remains around incorporating health administrative data due to accuracy limitations. The aim of this study is to explore the impact of pertussis case definitions and data accuracy on capture-recapture estimates. We used a dataset from March 7, 2010 to December 31, 2017 comprised of pertussis case report, laboratory, and health administrative data. We compared Chao capture-recapture abundance estimates using prevalence, incidence, and adjusted false positive case definitions. The latter was developed by removing the proportion of false positive physician billing code-only case episodes after validation. We calculated sensitivity by dividing the number of observed cases by abundance. Abundance estimates demonstrated that a high proportion of cases were missed by all sources. Under the primary analysis, the highest sensitivity of 78.5% (95% CI 76.2–80.9%) for those less than one year of age was obtained using all sources after adjusting for false positives, which dropped to 43.1% (95% CI 42.4–43.8%) for those one year of age or older. Most code-only episodes were false positives (91.0%), leading to considerably lower abundance estimates and improvements in laboratory testing and case report sensitivity using this definition. Accuracy limitations can be accounted for in capture-recapture analyses using different case definitions and adjustment. The latter enhanced the validity of estimates, furthering the utility of capture-recapture methods to epidemiological research. Findings demonstrated that all sources consistently fail to detect pertussis cases. This is differential by age, suggesting ascertainment and testing bias. Results demonstrate the value of incorporating real time health administrative data into public health surveillance if accuracy limitations can be addressed. [ABSTRACT FROM AUTHOR]