Progress of Measles and Rubella Surveillance in the Context of Measles Elimination in the WHO Eastern Mediterranean Region, 2019-2022.

In 2015, the 62nd session of the Regional Committee [RC] of the Eastern Mediterranean Region [EMR] endorsed the Eastern Mediterranean Vaccine Action Plan 2016-2020 (EMVAP) that included postponement of the measles elimination target to before 2020. However, the EMR does not have a regional rubella control or elimination goal. We reviewed the progress of measles and rubella surveillance in context of measles elimination in the Eastern Mediterranean Region during 2019-2022.

Global challenges and solutions to achieving and sustaining measles and rubella elimination.

Measles and rubella have long been recognized as priorities for disease prevention because of their devastating consequences for child health; hence, all World Health Organization (WHO) regions currently have a goal to eliminate measles and four out of six WHO regions have a goal to eliminate rubella. Significant global progress has been made in the twenty-first century, with more than 40% of countries in the world verified by a Regional Verification Commission as having eliminated measles and more than 50% of countries having sustained rubella elimination. Making further progress will require addressing fundamental gaps in health systems, a particular challenge in the current global context where many countries face multiple barriers to both sustaining and achieving measles and rubella elimination.

Progress Toward Measles Elimination - Worldwide, 2000-2023.

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.

Burden of infant group B disease and impact of maternal screening and antibiotic prophylaxis in Ontario, Canada: a population-based cohort study.

Background: Group B (GBS) significantly contributes to neonatal sepsis and meningitis, with varying disease rates reported globally and limited population-based data. We estimated infant GBS disease burden in Ontario, Canada and assessed the association of maternal GBS screening (35-37 weeks' gestation) and intrapartum antibiotic prophylaxis (IAP) provision with infant disease rates.

Methods: Our population-based cohort study included pregnant individuals and their offspring from April 2012 to March 2018, utilising the provincial birth registry linked to health administrative data.

Report from the World Health Organization's immunization and vaccines-related implementation research advisory committee (IVIR-AC) ad hoc meeting, 28 June - 1 July 2024.

The World Health Organization's Immunization and Vaccines-related Implementation Research Advisory Committee (IVIR-AC) serves to independently review and evaluate vaccine-related research to maximize the potential impact of vaccination programs. From 28 June - 1 July 2024, IVIR-AC was convened for an ad hoc meeting to discuss new evidence on criteria for rubella vaccine introduction and the risk of congenital rubella syndrome. This report summarizes background information on rubella virus transmission and the burden of congenital rubella syndrome, meeting structure and presentations, proceedings, and recommendations.

Global Status Report for the Verification of Measles and Rubella Elimination, 2022.

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.

Population immunity to varicella in Canada: A Canadian Immunization Research Network (CIRN) study.

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.

The Problem with Delaying Measles Elimination.

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.

Effectiveness of Influenza Vaccination During Pregnancy Against Laboratory-Confirmed Seasonal Influenza Among Infants Under 6 Months of Age in Ontario, Canada.

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.

Progress Toward Rubella and Congenital Rubella Syndrome Elimination - Worldwide, 2012-2022.

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, including cataracts, deafness, heart defects, and developmental delay, known as congenital rubella syndrome (CRS). A single dose of rubella-containing vaccine can provide lifelong protection against rubella.

Measuring waning protection from seasonal influenza vaccination during nine influenza seasons, Ontario, Canada, 2010/11 to 2018/19.

BackgroundWaning immunity from seasonal influenza vaccination can cause suboptimal protection during peak influenza activity. However, vaccine effectiveness studies assessing waning immunity using vaccinated and unvaccinated individuals are subject to biases.AimWe examined the association between time since vaccination and laboratory-confirmed influenza to assess the change in influenza vaccine protection over time.

Progress Toward Measles Elimination - World Health Organization Eastern Mediterranean Region, 2019-2022.

In 2015, all 22 World Health Organization Eastern Mediterranean Region (EMR) countries and areas (countries) pledged to achieve measles elimination by 2020. Despite success in several countries, most countries in the region still have not eliminated measles. This report updates a previous report and describes progress toward measles elimination in EMR during 2019-2022.

Validating pertussis data measures using electronic medical record data in Ontario, Canada 1986-2016.

Background: Pertussis is a reportable disease in many countries, but ascertainment bias has limited data accuracy. This study aims to validate pertussis data measures using a reference standard that incorporates different suspected case severities, allowing for the impact of case severity on accuracy and detection to be explored.

Methods: We evaluated 25 pertussis detection algorithms in a primary care electronic medical record database between January 1, 1986 and December 30, 2016.

Improving estimates of pertussis burden in Ontario, Canada 2010-2017 by combining validation and capture-recapture methodologies.

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.

Progress Toward Measles Elimination - Worldwide, 2000-2022.

Measles is a highly contagious, vaccine-preventable disease that requires high population immunity for transmission to be interrupted. All six World Health Organization regions have committed to eliminating measles; however, no region has achieved and sustained measles elimination. This report describes measles elimination progress during 2000-2022.

Maternal varicella antibodies in children aged less than one year: Assessment of antibody decay.

Objectives: To investigate maternal antibody levels to varicella in infants <12 months of age in Ontario, Canada.

Study Design: In this study, we included specimens from infants <12 months of age, born at ≥37 weeks gestational age, who had sera collected at The Hospital for Sick Children (Toronto, Canada) between 2014-2016. We tested sera using a glycoprotein-based enzyme-linked immunosorbent assay (gpELISA).

Uptake of pertussis immunization in pregnancy and determinants of vaccination in Toronto, Canada.

Introduction: Pertussis causes significant morbidity and mortality in infants aged <6 months. Maternal pertussis vaccination during pregnancy has been recommended in Canada since 2018 to reduce these negative outcomes. In the absence of routine immunization coverage data, our objective was to evaluate uptake in Toronto, Canada.

Country ownership as a guiding principle for IA2030: A case study of the measles and rubella elimination programs in Nepal and Nigeria.

Country-owned, as opposed to donor-driven, is a principle within the development sector that recognizes the centrality of countries' leadership, systems, and resources in executing programs and achieving sustainable development. In alignment with this notion, the Immunization Agenda 2030 was developed with country ownership as one of four core principles of the ambitious ten-year plan. This means that the success of immunization programs, including those with eradication and elimination goals such as polio, measles, and rubella, and those with broader equity goals to "leave no one behind" on immunization, would be largely driven by country systems.

Immunity of Canadians and risk of epidemics workshop - Conference report.

On November 18-19, 2019, the Immunity of Canadians and Risk of Epidemics (iCARE) Network convened a workshop in Toronto, Ontario, Canada. The objectives of the workshop were to raise the profile of sero-epidemiology in Canada, discuss best practice and methodological innovations, and strategize on the future direction of sero-epidemiology work in Canada. In this conference report, we describe the presentations and discussions from the workshop, and comment on the impact of the COVID-19 pandemic on serosurveillance initiatives, both in Canada and abroad.

Population-Level Risk Factors Related to Measles Case Fatality: A Conceptual Framework Based on Expert Consultation and Literature Review.

A better understanding of population-level factors related to measles case fatality is needed to estimate measles mortality burden and impact of interventions such as vaccination. This study aimed to develop a conceptual framework of mechanisms associated with measles case fatality ratios (CFRs) and assess the scope of evidence available for related indicators. Using expert consultation, we developed a conceptual framework of mechanisms associated with measles CFR and identified population-level indicators potentially associated with each mechanism.

Progress Toward Rubella Elimination - World Health Organization South-East Asia Region, 2013-2021.

During 2013, the 11 countries of the World Health Organization (WHO) South-East Asia Region* (SEAR) adopted the goals of measles elimination and rubella and congenital rubella syndrome (CRS) control by 2020. During 2019, SEAR countries declared a broader goal for eliminating both measles and rubella by 2023 (1). Before 2013, only five SEAR countries had introduced rubella-containing vaccine (RCV).

Comparison of measles IgG enzyme immunoassays (EIA) versus plaque reduction neutralization test (PRNT) for measuring measles serostatus: a systematic review of head-to-head analyses of measles IgG EIA and PRNT.

Background: As countries move towards or achieve measles elimination status, serosurveillance is an important public health tool. However, a major challenge of serosurveillance is finding a feasible, accurate, cost-effective, and high throughput assay to measure measles antibody concentrations and estimate susceptibility in a population. We conducted a systematic review to assess, characterize, and - to the extent possible - quantify the performance of measles IgG enzyme-linked assays (EIAs) compared to the gold standard, plaque reduction neutralization tests (PRNT).

Evaluating the Impact of Statin Use on Influenza Vaccine Effectiveness and Influenza Infection in Older Adults.

Background: Older adults are recommended to receive influenza vaccination annually, and many use statins. Statins have immunomodulatory properties that might modify influenza vaccine effectiveness (VE) and alter influenza infection risk.

Methods: Using the test-negative design and linked laboratory and health administrative databases in Ontario, Canada, we estimated VE against laboratory-confirmed influenza among community-dwelling statin users and nonusers aged ≥66 years during the 2010-2011 to 2018-2019 influenza seasons.

Evaluation of the effectiveness of maternal immunization against pertussis in Alberta using agent-based modeling: A Canadian immunization research network study.

Introduction: The re-emergence of pertussis has occurred in the past two decades in developed countries. The highest morbidity and mortality is seen among infants. Vaccination in pregnancy is recommended to reduce the pertussis burden in infants.

Trends and characteristics of Tdap vaccination during pregnancy in Ontario, Canada: a retrospective cohort study.

Background: In February 2018, Canada's National Advisory Committee on Immunization (NACI) recommended tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccination during pregnancy to protect newborns against pertussis infection. We sought to describe pre- and postrecommendation trends in Tdap vaccination coverage among pregnant Ontario residents.

Methods: Using linked health administrative databases, we conducted a population-based retrospective cohort study of all pregnant individuals who gave birth in Ontario hospitals between April 2012 and March 2020.