Search Results (81)

Background: Despite ongoing global elimination efforts, measles remains a persistent public health threat. Methods: This retrospective observational study examines trends in crude measles incidence and vaccination coverage from 1948 to 2024 in the northern region of Serbia—Autonomous Province of Vojvodina (AP Vojvodina)—which accounts for 26.9% of the national population. This study further explores measles vaccination coverage across the province’s seven districts, along with the number of reported measles cases, age distribution, and vaccination status of affected individuals from 2000 to 2024. Data were obtained from official annual immunization records maintained by public health institutions within the framework of Serbia’s national mandatory immunization program. Results: A notable resurgence of measles occurred in Serbia during 2017–2018, following a decline in vaccination coverage. In AP Vojvodina, outbreaks were recorded in 2007, 2014–2015, and 2017–2018, predominantly affecting unvaccinated children and adults aged 20–39 years. Since 2019, the measles incidence has significantly declined. During the 2018 outbreak, the highest incidence was observed among children aged 1–4 years (40.6 per 100,000), followed by infants under 1 year (17.3 per 100,000) and adults aged 20–39 years (12.5 per 100,000). An analysis of the data from 2000 to 2024 revealed substantial age- and dose-related differences in measles incidence, particularly among unvaccinated individuals, those who had received one or two doses of a measles-containing vaccine (MCV), and those with unknown vaccination status. During the 2017–2018 epidemic, unvaccinated children under 1 year and those aged 1–4 years were the most affected. A marked increase in cases among single-dose recipients was noted in 2018, especially in adults aged 20–39 years (9.5%) and those ≥40 years (13.5%). A considerable proportion of measles cases in these age groups had unknown vaccination status: 33.1% among individuals aged 20–39 years and 18.2% among those aged ≥ 40 years. Epidemiological investigation linked the 2007 and 2014–2015 outbreaks in AP Vojvodina to importations from Bosnia and Herzegovina. No specific source was identified for the 2017–2018 outbreak, suggesting possible endemic transmission. Conclusions: These findings underscore the impact of fluctuating vaccination coverage on measles resurgence. Sustaining high two-dose MCV coverage, strengthening routine immunization programs, enhancing surveillance systems, and ensuring timely outbreak preparedness are critical measures for achieving effective measles control. Full article

Between 2018 and 2019, Israel experienced one of its largest measles outbreaks in recent decades, with over 4300 reported cases and more than 100 documented importation events. Despite high national vaccination coverage, the prolonged nature of the outbreak posed a risk to the country’s measles elimination status. Traditional epidemiological investigations and genotyping based on the N450 region lacked sufficient resolution to differentiate between sustained local transmission and multiple independent introductions. To address this, we performed whole-genome sequencing on 123 measles virus samples representing both imported and locally acquired cases from diverse geographic regions. Phylogenetic analysis revealed multiple, distinct transmission chains, several of which could be linked to separate importation events. The MF non-coding region (MF-NCR) not only showed the highest genetic variability, but also contained many of the phylogenetic cluster-defining mutations, though informative changes were found throughout the whole genome. These findings demonstrate the value of whole-genome sequencing in resolving complex transmission dynamics and highlight the importance of integrating genomic epidemiology into routine measles surveillance. Such integration can enhance outbreak investigations and better inform public health responses to protect elimination status. Full article

Measles is a highly contagious viral disease and remains a global health challenge despite the availability of effective vaccines. Although many regions have successfully eliminated measles, outbreaks continue to occur owing to vaccine hesitancy, inadequate coverage, and imported cases. Differences in epidemiology, vaccination policies, and immunity assessment influence measles control across countries. This paper compares measles epidemiology, vaccination policies, and immunity assessment approaches in the United States and Japan. Data were obtained from surveillance reports, national immunization programs, and peer-reviewed literature. The introduction of the measles vaccine led to substantial reductions in incidence. The United States eliminated measles in 2000 but continues to experience outbreaks due to vaccine hesitancy and imported cases. Japan implemented a two-dose policy in 2006, reducing case numbers; however, sporadic outbreaks among adults persist. In the United States, immunity is primarily assessed using documented vaccination history, whereas in Japan, enzyme immunoassay is commonly used to evaluate immunity status. Despite progress in measles elimination, achieving high vaccination coverage and addressing vaccine hesitancy remain critical challenges. Variations in immunity assessment methods impact surveillance accuracy and outbreak control. Strengthening international collaboration, standardizing assessment protocols, and enhancing public health education are crucial for sustained measles elimination. Full article

Mpox is a zoonotic disease caused by the Mpox virus (MPXV). The rapid and accurate diagnosis of MPXV is essential for the timely and effective prevention, control, and treatment of the disease. In this study, we combined Multienzyme Isothermal Rapid Amplification (MIRA) (at 42 °C) and Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 12b(CRISPR/Cas12b) (at 60 °C) to develop a single-tube two-step assay for rapid MPXV detection, leveraging the distinct physical states of tricosane at these temperatures. MIRA amplification primers and CRISPR/cas12b SgRNA were designed based on the MPXV F3L gene. After screening the primers and sgRNAs, the reaction conditions were optimized, and the performances of the assay were evaluated. The detection limit (LOD) of this single-tube two-step MIRA-CRISPR/Cas12b assay for MPXV is four copies of DNA molecules. No cross-reactivity with other pathogens (herpes simplex virus (HSV), Epstein–Barr virus (EBV), Coxsackievirus A16 (CVA16), Enterovirus A71 (EV-A71), and measles virus (MeV)) was found. The assay also showed good consistency with quantitative real-time PCR (qPCR) (Kappa = 0.9547, p < 0.05, n = 100) in the detection of clinical samples, with a sensitivity of 98.5% and a specificity of 97.0%. The single-tube two-step MIRA-CRISPR/Cas12b assay permits the rapid (within 45 min), sensitive, and specific detection of MPXV. The lack of need for opening the reaction tube eliminates the risk of product contamination. Full article

The COVID-19 pandemic has led to significant increases in morbidity, mortality, and energy consumption, primarily due to infection control measures. Hospitals, as frontline responders, are particularly vulnerable to infection risks due to dense populations and numerous viral carriers. Integrating natural ventilation to optimize air-conditioning systems is crucial for mitigating these risks while balancing energy efficiency. However, existing research has predominantly focused on mechanical ventilation upgrades, with limited attention given to the effective integration of natural ventilation. This study presents an innovative air-conditioning system that incorporates easily installable automatic window control units into existing fresh-air-handling units and fan coil unit systems. This approach allows for multi-zone simultaneous control, making it suitable for both new and retrofitted hospitals. Additionally, the study proposes an optimal multi-zone ventilation strategy aimed at reducing infection risks while enhancing energy efficiency. The performance of the proposed system and ventilation strategy is evaluated considering five common respiratory diseases, with their seasonal transmission characteristics across a wide range of climatic conditions integrated into a revised version of the traditional Wells–Riley equations. The results demonstrate that conventional systems, following China’s GB55015-2021 standard, incur high infection risks during peak-season hours for COVID-19 (1347 h), influenza (470 h), and measles (1386 h). In contrast, the proposed multi-zone ventilation strategy eliminates infection risks while only increasing energy consumption by 3–10%, utilizing outdoor wind pressure as a key resource. This solution not only enhances hospital resilience but also provides valuable technical guidance for the design and retrofitting of hospital buildings, ensuring enhanced infection control and energy efficiency across diverse climates. Full article

Objectives: The objectives of this study were as follows: to determine mean percentages of measles vaccination coverage with zero, one and two doses of vaccine and anti-measles herd immunity levels in World Health Organization (WHO) regions in 2023; to assess variations in measles vaccination coverage and anti-measles herd immunity-related indicators from 2019 to 2023; and to assess whether zero-dose measles vaccination coverage indicators were on track to achieve the Immunization Agenda 2030 objective. Methods: Mean percentages of vaccination coverage with two, one and zero doses of measles vaccine in WHO regions in 2023 were calculated using data from the WHO/UNICEF global and regional immunization information system. Results: In 2023, the global mean two-dose measles vaccination coverage was 65.3%, and mean two-dose vaccination coverage was lower than 95% in all WHO regions; the mean prevalence of measles-protected individuals in the target vaccination population was 87.6%, and anti-measles herd immunity levels in the target vaccination population were sufficient to block the transmission of measles viruses with greater transmissibility (R_o ≥ 15) only in the Western Pacific and European WHO regions. The global mean two-dose measles vaccination coverage decreased by 3.7% from 2019 to 2023. In 2023, the mean zero-dose measles coverage and number of zero-dose measles children were, respectively, 36.7% and 40.6% greater than the values required to be on track to achieve the 2030 objective. Conclusion: This study found that all measles-vaccination-coverage-related indicators worsened from 2019 to 2023, and the zero-dose measles vaccination coverage and number of zero-dose measles children in 2023 were not on track to achieve the AI2030 objective. Interventions to increase routine two-dose measles vaccination coverage should be developed in all WHO regions. Full article

Background: The vaccination programmes after the 2nd World War and the application of safe and effective vaccines were expected to eliminate infectious diseases within the World Health Organization (WHO) European Region. However, epidemiological indexes show isolated cases and local epidemiology outbreaks of viral measles, that draw attention to re-evaluate the effectiveness and obstacles of infectious disease eradication programmes. Methodology: This study analyses the available Polish governmental epidemiological data concerning the WHO European Region for the years 2003–2014 and evaluates the effectiveness of the WHO Measles Eradication Programme implementation, since 2001. Most of these epidemiological data are either available in Polish or scattered in governmental reports only. Thus, we have compiled selected available data to present an overview focusing on Poland’s measles epidemiological situation. Results: The analysis of the available data clearly shows that infection cases of measles are on the rise in the European Region or are steady at a relatively high level depending on the country. The critical factors to prevent measles are maintaining a vaccination level at a minimum of 95% using two doses of MMR, adequate infection detection, rapid reporting, controlling and enforcing identification, and mass media campaigns to inform societies about the necessity of measles vaccination and the safety of using MMR. Conclusions: Besides the current SARS-CoV-2 pandemics, measles is possibly the most dominating infectious disease on the rise in the European Region, including Poland. The eradication programme modifications to increase its effectiveness are of upmost importance, as measles is one of the most infectious diseases with acute syndromes, especially affecting children. Full article

Background/Objectives: Spain has been in a measles elimination phase since 2014. No evidence exists about the distribution of measles cases among the population born outside Spain. The aim of this study was thus to describe the epidemiological situation of measles, stratified by place of birth, during the post-elimination period in Spain. Methods: This is a retrospective study of confirmed measles cases reported to RENAVE between 2014 and 2022. A descriptive analysis of case characteristics (sex, age group, vaccination status, imported case) was performed, was well as an analysis of temporal trends and geographic distribution in measles incidence rate (IR; cases/million inhabitants). All analyses were stratified by place of origin (Spain born vs. born outside Spain). We then performed a sensitivity analysis of those born outside Spain, with the representation of Kaplan–Meier curves taking into account the year of arrival in the country until the onset of measles. Results: Between 2014 and 2022, 951 measles cases were reported in Spain (overall IR: 2.3). Among these, 18.6% (177 cases, IR: 3.0) were born outside Spain. The IRs show differences (p < 0.001) in terms of distribution by age group and origin. By age group, children under 5 years had the highest IR, but adults aged 30 years and older reported the highest proportion of cases. The incidence rate ratio (IRR) was 5-fold higher among foreign-born children under 5 years than among native-born children. The measles time trend shows the highest peak in 2019 for foreign-born and native-born (IR: 8.6 and 5.4, respectively), consistent with the European-wide scenario, while only one case of measles was reported in 2022. Geographical variability in incidence rates by region was observed: Catalonia and the Valencian Community accumulated the highest proportion of cases throughout the study period. Among those born outside Spain, the median time from arrival to onset of rash was 6 years. Conclusions: The incidence of measles is 40% higher in Spain’s foreign-born population than in its native-born population. Taking into account the increasing migrant population in Spain, we consider that public health efforts need to be directed towards susceptible groups of people. In this context of advanced elimination, specific interventions for identifying and attending the most vulnerable populations should be designed and implemented. Full article

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. We compiled data on coverage, reported cases, surveillance indicators, incidence, and genotypes. We conducted an age-cohort analysis to estimate the size of the susceptible population using coverage and SIAs coverage data. We reviewed the dossiers of countries that applied to the Regional Verification Commission [RVC] for the verification of measles and rubella elimination. Between 2019 and 2022, the regional coverage of the vaccine against measles and rubella was stable at 83% for the first dose [MCV1] and increased from 75% to 78% for the second dose [MCV2] after a dip during COVID-19. In the EMRO, eighteen countries are using MR (measles–rubella) and/or measles–mumps–rubella (MMR) vaccines and four are using measles vaccines. The reported regional measles incidence per 1,000,000 was 23.3 in 2019, decreased to 7.4 in 2020, and re-increased to 50 in 2022, with two main genotypes–D8 and B3–in circulation. Both genotypes are considered to be actively circulating in eighteen countries, with different circulating variants of each genotype. There were no genotyping data available from four countries. Measles and rubella surveillance indicators deteriorated in the region. The number of susceptible individuals exceeded one birth cohort in nine of the 22 countries. In 2019–2022, Bahrain, Egypt, Iran, and Oman were verified to have eliminated measles and rubella. While four countries eliminated measles and rubella and another five progressed toward measles and rubella elimination, however, immunity gaps and reported incidence increased in eleven countries. Countries approaching elimination need to prepare verification dossiers, while others need to increase their routine coverage, conduct follow-up campaigns, and improve surveillance. Submission of progress reports to the RVC will measure progress toward the goal. Full article

Background: The Measles–Rubella Microarray Patch (MR-MAP) is an important technology that is expected to reduce coverage and equity gaps for measles-containing vaccines (MCVs), reach zero-dose children, and contribute to elimination of measles and rubella. MR-MAPs are anticipated to be easier to deploy programmatically and could be delivered by lesser-trained health workers, thereby increasing immunization coverage. The most advanced MR-MAP has reached clinical proof-of-concept through a Phase I/II trial in the target population of infants and young children. The World Health Organization (WHO) and partners have developed the Phase III clinical trial framework for MR-MAPs presented in this article. Objectives and Methods: The purpose of such framework is to inform the considerations, design and approach for the pivotal clinical trial design, while considering the anticipated data requirements to inform regulatory approval, WHO prequalification, and policy decision. Results: The proposed Phase III trial would compare the immunogenicity and safety of an MR-MAP with MR vaccine delivered subcutaneously in 9- to 10-month-old infants. An analysis of non-inferiority (NI) of immunogenicity would occur six weeks after the first dose. Should regulatory agencies or policy makers require, a proportion of infants could receive a second dose of either the same or alternate MR vaccine presentation six months after the first dose, with those children returning six weeks after the second dose for a descriptive assessment of immunogenicity, and then followed up six months after the second dose for evaluation of safety and immunogenicity. It is anticipated that this proposed pivotal Phase III trial framework would generate the required clinical data for regulatory licensure and WHO prequalification (PQ) of MR-MAPs. However, the trial design would need to be reviewed and confirmed by a national regulatory authority (NRA) that will assess the product for regulatory licensure and the WHO PQ team. Additional research will likely be required to generate data on concomitant vaccine delivery, the safety and immunogenicity of MR-MAPs in other age groups such as children 1–5 years and infants younger than 9 months of age, and the impact of MR-MAPs on coverage and equity. Such studies could be conducted during or after clinical MR-MAP development. Full article

Background: Measles elimination strategies include supplementary immunization activities (SIAs) to rapidly fill immunity gaps. Post-campaign coverage surveys (PCCSs) are recommended to assess SIA coverage. We characterized selected PCCSs performed following recent SIAs, highlighting specific challenges and strengths, and provide recommendations for improvement. Methods: We extracted national SIA data from the global measles/MR SIA database for the period of 2020–2023 and reviewed PCCS reports available at the World Health Organization headquarters. We extracted selected information on PCCS implementation, including information about the implementer, sampling, and main results. Results: Only 15 of 66 countries (23%) with a national-level SIA performed since 2020 had a PCCS report available. We reviewed those reports, plus six more, following three 2019 SIAs with a delayed PCCS and two PCCSs following large subnational SIAs (Kenya 2021 and Yemen 2023). All 24 PCCS reports available were from Gavi-eligible countries, with 15 from South Saharan Africa (Cameroon, the Democratic Republic of the Congo, and Ethiopia had two PCCSs). Eleven (45.8%) PCCSs were conducted within three months of the end of the SIA. All included sampling information and most had percentage of participation. Description of the interviewers’ profiles varied but was limited. PCCS coverage was lower than administrative data in all but two instances. All PCCSs collected data on previous measles vaccination status that would allow exploring indicators on the SIA reaching previously measles zero-dose children. Of the 12 PCCSs reporting coverage among previously measles zero-dose children, nine reported coverage among this group of more than 50% (range: 12% and 91.6%). Conclusion: Even though a PCCS following an SIA is recommended and a requirement in Gavi-supported countries, most SIAs are not followed by a PCCS and, when performed, the timeliness of survey implementation needs improvement. Recent PCCSs were independently conducted and reports included basic survey information, but analysis and presentation of survey results vary particularly for measles zero-dose-related indicators. More guidance and technical support on how to implement PCCSs, including standardization of reports and more in-depth PCCS analyses, may help improve reporting and use of available PCCS data. Full article

Background: Prior to measles vaccine introduction in 1963, measles virus caused hundreds of thousands of annual reported cases, which led to substantial US morbidity, mortality, and costs. Similarly, congenital rubella syndrome (CRS) led to highly visible and tragic lifelong disability for thousands of Americans, before rubella vaccine introduction in 1969. The US certified national virus transmission elimination of indigenous measles in 2000 and rubella in 2004. Methods: Applying an existing integrated transmission and economic model, this analysis characterizes the net benefits of US investments in measles (1963–2030) and rubella (1969–2030) immunization assuming continued high routine immunization coverage. Due to importation risks, the US maintains two doses of both vaccines in its routine immunization schedule. Results: This analysis estimates total US costs of 8.1 billion (economics reported in 2023 US dollars) for measles immunization for 1963–2023 and 14.1 billion for rubella immunization for 1969–2023. The analysis estimates an additional approximately 1.2 billion for measles immunization and 1.5 billion for rubella immunization expected for 2024–2030. Historical and future US investments prevented an estimated approximately 237 million measles infections, 228,000 measles deaths, 193 million rubella infections, and 166,000 CRS cases. These investments imply net benefits (from avoided treatment costs minus immunization costs) of approximately 310 billion for measles and 430 billion for rubella and CRS, even without incorporating avoided productivity losses and intangible costs. Conclusions: US investments in measles and rubella immunization continue to provide enormous savings of human and financial costs and to prevent substantial mortality and morbidity. Full article

The South-East Asia (SEA) Region of the World Health Organization (WHO), through a Regional Committee resolution in 2013, adopted the goal of “measles elimination and rubella control by 2020”. The goal was revised in 2019 to “measles and rubella elimination by 2023”. Countries of the Region have made significant efforts to achieve the goal. Progress has been made in the Region, with five of the 11 countries of the Region having been verified for having eliminated measles and rubella. Surveillance and immunization program performance for measles and rubella has shown an improvement since 2013. This progress has been possible due to a high level of political and programmatic commitment in the countries of the Region, as well as due to the alliances and infrastructures established for disease elimination initiatives in the past, notably for polio, being utilized effectively to implement strategies for measles and rubella elimination. The unforeseen COVID-19 pandemic had a detrimental effect on the immunization and surveillance efforts, leading to a delay in the achievement of measles and rubella elimination in the Region. Challenges to achieve the goal remain; however, efforts are ongoing in countries to not only protect the gains made so far but also to make further progress towards the goal of measles and rubella elimination. Full article

Despite the availability of an effective vaccine for several decades, the measles virus continues to spread worldwide. From 2018 to 2019, several countries experienced large measles outbreaks with genotype B3, including Tunisia. We analyzed 66 samples collected from serologically confirmed measles cases during this outbreak. Fifty-five percent were aged less than 12 months and had not received a measles vaccine. Phylogenetic analysis using the 450 nucleoprotein (N450) window revealed that all strains belonged to genotype B3, with five different variants identified. The N450 sequence of the predominant one, which circulated all through the epidemic period, was identical to the named strain MVs/Kabul.AFG/20.14/3. For better molecular discrimination, the amplification and sequencing of 1018 nucleotides in the non-coding region between the M and F genes (MF-NCRs) revealed higher variability with at least nine clusters. A phylogeographic study using Bayesian methods suggested the Governorate of Kasserine (on the borders of Algeria) as the introduction point with a TMRCA (Time to Most Recent Common Ancestor) for the 2019 sequences estimated around October 2018. These findings emphasize the crucial role of advanced molecular investigations in tracing measles transmission pathways which, together with good vaccine coverage, will help the final success of the global measles elimination program. Full article

Background: Microarray patches (MAPs) are innovative, needle-free vaccine delivery systems, suitable for administration by minimally trained health care workers or trained community health workers. Their introduction may transform immunization programmes, particularly for vaccines where high coverage is required for population immunity, such as measles, and where vaccine delivery is challenging, such as in low- and middle-income countries. Recognizing the need to understand how best to tailor these products to reflect country priorities, workshops on measles and rubella MAPs (MR-MAPs) were conducted in multiple regions to collect insights on needs and preferences from relevant stakeholders at country level. Methods: The CAPACITI Innovation Framework was used to structure stakeholder discussions in nine countries in the period from August 2022 to July 2023. The discussions, building on the findings from a situation analysis on the barriers related to measles and rubella vaccine delivery, followed the four-step process outlined in the framework. Results: Key barriers hindering delivery of measles and rubella vaccines across the countries were in the categories of human resource management, service delivery, and demand generation. MR-MAP attributes that stakeholders believed would reduce or eliminate these barriers included ease of preparation and administration, improved thermostability, fewer (ancillary) components, and single-dose presentation. Some attributes such as the site of administration, wear time, and storage volume could exacerbate certain barriers. Based on an understanding of key barriers, product attributes, and underserved populations, stakeholders identified several potential use cases for MR-MAPs: (i) delivery at a fixed health post, (ii) delivery through outreach sessions conducted by health workers, and (iii) administration by community health workers. To enable robust national decision making about the introduction of MR-MAPs and successful implementation, global and national evidence on feasibility and acceptability of MR-MAPs should be generated. To prepare for the potential introduction of MR-MAPs, immunization programmes should evaluate their immunization policies based on their preferred use cases and modify them if needed, for example, to enable community health workers to administer vaccines, along with making programmatic adjustments to waste management and training. Conclusions: MR-MAPs have the potential to reduce key barriers to MR delivery. Yet, their future impact depends on the ability of global stakeholders to steer the development of MR-MAPs to be responsive to country needs and preferences. The generation of evidence to enable robust decision making, timely modification of vaccine policies, and addressing programmatic considerations will be key to successful uptake. Full article