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Vaccines Jun 2024Mongolia experienced a nationwide measles outbreak during 1 March 2015-31 December 2016, with 49,077 cases reported to the WHO; many were among vaccinated young adults,...
Mongolia experienced a nationwide measles outbreak during 1 March 2015-31 December 2016, with 49,077 cases reported to the WHO; many were among vaccinated young adults, suggesting a possible role of vaccine failure. Advanced laboratory methods, coupled with detailed epidemiological investigations, can help classify cases as vaccine failure, failure to vaccinate, or both. In this report, we conducted a study of cases to identify risk factors for breakthrough infection for a subset of laboratory-confirmed measles cases. Of the 193 cases analyzed, only 19 (9.8%) reported measles vaccination history, and 170 (88%) were uncertain. Measles-specific IgG avidity testing classified 120 (62%) cases as low IgG avidity, indicating no prior exposure to measles. Ten of these cases with low IgG avidity had a history of measles vaccination, indicating primary vaccine failure. Overall, sixty cases (31%) had high IgG avidity, indicating breakthrough infection after prior exposure to measles antigen through vaccination or natural infection, but the IgG avidity results were highly age-dependent. This study found that among young children aged 9 months-5 years, breakthrough infection was rare (4/82, 5%); however, among young adults aged 15-25 years, breakthrough infection due to secondary vaccine failure (SVF) occurred on a large scale during this outbreak, accounting for the majority of cases (42/69 cases, 61%). The study found that large-scale secondary vaccine failure occurred in Mongolia, which highlights the potential for sustained outbreaks in post-elimination settings due to "hidden" cohorts of young adults who may have experienced waning immunity. This phenomenon may have implications for the sustainability of measles elimination in countries that remain vulnerable to the importation of the virus from areas where it is still endemic. Until global measles elimination is achieved, enhanced surveillance and preparedness for future outbreaks in post- or peri-elimination countries may be required.
PubMed: 38932425
DOI: 10.3390/vaccines12060695 -
Vaccines Jun 2024The elimination of both measles and rubella remains a priority for all 53 Member States of the World Health Organization (WHO) European Region. To provide an update on...
The elimination of both measles and rubella remains a priority for all 53 Member States of the World Health Organization (WHO) European Region. To provide an update on the epidemiological status of measles and rubella in the Region, we reviewed surveillance data on both diseases for 2023 submitted monthly by national surveillance institutions. We analyzed the cases of measles and rubella for 2023 by age group, case classification, vaccination, hospitalization, and importation status and report on measles-related deaths. In 2023, 60,860 measles cases, including 13 fatal cases, were reported in 41 countries. Most cases (95%; n = 57,584) were reported by six countries: Azerbaijan, Kazakhstan, Kyrgyzstan, Romania, the Russian Federation, and Türkiye. Of the 60,848 cases with data on age, 19,137 (31%) were 1-4 years old and 12,838 (21%) were 5-9 years old. A total of 10,412 (17%) were 20 years and older. The genotypes identified in the Region were largely dominated by D8 variants (n = 1357) and the remainder were B3 variants (n = 221). In 2023, 345 rubella cases were reported by 17 countries, mostly from Poland, Kyrgyzstan, Tajikistan, Türkiye, and Ukraine. A total of 262 cases (76%) were classified as clinically compatible and 79 (23%) were laboratory-confirmed. To achieve the elimination of measles and rubella in the Region, political commitment needs to be revived to enable urgent efforts to increase vaccination coverage, improve surveillance and outbreak preparedness, and respond immediately to outbreaks.
PubMed: 38932424
DOI: 10.3390/vaccines12060696 -
Vaccines Jun 2024The worldwide elimination of measles and rubella is feasible, but not without overcoming the substantial challenge of vaccine hesitancy. This challenge is complicated by... (Review)
Review
The worldwide elimination of measles and rubella is feasible, but not without overcoming the substantial challenge of vaccine hesitancy. This challenge is complicated by the spread of misinformation and disinformation fueled by rapidly progressing technologies and evolving forms of online communication. The recent COVID-19 pandemic has only added further complexity to this challenge. However, considerable progress has been made in understanding the scope of the problem and the complex factors that influence vaccine hesitancy. Our understanding of evidence-based strategies for addressing vaccine hesitancy has grown significantly, including evidence for effective communication and behavioral interventions. In this article, we review measles and rubella vaccines and vaccine hesitancy. We then provide an overview of evidence-based strategies for addressing vaccine hesitancy, including communication strategies and behavioral interventions. This article is relevant to healthcare professionals, health system leaders, public health professionals, policymakers, community leaders, and any individuals who have a role in addressing vaccine hesitancy in their communities. Finally, we review future directions and major areas of research need.
PubMed: 38932423
DOI: 10.3390/vaccines12060694 -
Vaccines Jun 2024This article describes the arc of global measles and rubella elimination since 2000 from the perspective of the founding partners of the Measles Initiative. The Measles...
This article describes the arc of global measles and rubella elimination since 2000 from the perspective of the founding partners of the Measles Initiative. The Measles Initiative was formed in 2001 as a partnership among the American Red Cross, the Centers for Disease Control and Prevention, UNICEF, the United Nations Foundation, and the World Health Organization with the aim to reduce measles deaths in low-income countries. Recognizing rubella as the leading infectious disease cause of congenital abnormalities globally and achievement of measles and rubella elimination in the region of the Americas, the partnership was renamed the Measles and Rubella Initiative (MRI) in 2012. The goals of the MRI were at least a 95% reduction in global measles mortality and elimination of measles and rubella in at least five of the six WHO regions. In January 2023, the membership of the partnership was expanded to include the Bill and Melinda Gates Foundation (BMGF) and Gavi the Vaccine Alliance, and its name changed to the IA2030 Measles and Rubella Partnership. We describe the role the partnership has had in measles partner effectiveness and its impact on measles and rubella disease burden, including how the partnership has strategically adapted to the evolving immunization landscape. We conclude with lessons learned regarding the role global partnerships can play in furthering the impact of disease control programs within the current global immunization environment.
PubMed: 38932422
DOI: 10.3390/vaccines12060693 -
Vaccines Jun 2024Global measles cases are on the rise following disruptions to routine immunisation programs during the COVID-19 pandemic, with devastating consequences. According to the...
Global measles cases are on the rise following disruptions to routine immunisation programs during the COVID-19 pandemic, with devastating consequences. According to the World Health Organization, the behavioural and social drivers of vaccination include what people think and feel about vaccines, social processes, motivation to vaccinate and practical barriers to vaccination. However, the drivers of measles vaccine uptake are not necessarily the same as those for other childhood vaccines, and we lack data on how these drivers specifically have changed during and since the COVID-19 pandemic. Without accurately measuring the behavioural and social drivers for measles vaccination, and ideally measuring them serially over time, countries cannot design, target and implement interventions that effectively increase and sustain measles vaccine coverage. This paper outlines what is and is not known about the behavioural and social drivers of measles vaccination and provides recommendations for improving their post-pandemic assessment.
PubMed: 38932421
DOI: 10.3390/vaccines12060692 -
Vaccines Jun 2024This report reviews national data from all Member States on measles, rubella, and congenital rubella syndrome (CRS) elimination in the Region of the Americas during... (Review)
Review
This report reviews national data from all Member States on measles, rubella, and congenital rubella syndrome (CRS) elimination in the Region of the Americas during 2019-2023. It includes an analysis of compliance with vaccination coverage, surveillance indicators, and measles outbreaks, as well as an analysis of the response capacity of the laboratory network and a country case study that meets all indicators. The sources of information were the integrated epidemiological surveillance system for measles and rubella of the Pan American Health Organization (PAHO)/World Health Organization (WHO) and the Joint Reporting Form (eJRF), among others. From 2020 to 2022, regional coverage with first (MMR-1) and second doses (MMR-2) decreased to rates below 90%. The regional suspected case notification rate was maintained above the minimum expected 2.0 suspect cases per 100,000 population, except in 2021. During 2019 to 2023, 18 countries experienced outbreaks, with two of the outbreaks resulting in re-established endemic transmission. In conclusion, two countries in the Americas have not maintained measles elimination, but by the end of 2023 no country showed endemic measles transmission. One of the countries that lost its certification of elimination in 2018 managed to be reverified in 2023; the other is pending reverification. All countries maintained rubella elimination. Despite these challenges, the sustainability of the elimination of these diseases remains a health priority in the Region.
PubMed: 38932419
DOI: 10.3390/vaccines12060690 -
Vaccines May 2024Measles seroprevalence data have potential to be a useful tool for understanding transmission dynamics and for decision making efforts to strengthen immunization... (Review)
Review
BACKGROUND
Measles seroprevalence data have potential to be a useful tool for understanding transmission dynamics and for decision making efforts to strengthen immunization programs. In this study, we conducted a systematized review and bias assessment of all primary data on measles seroprevalence in low- and middle-income countries (as defined by World Bank 2021 income classifications) published from 1962 to 2021.
METHODS
On 9 March 2022, we searched PubMed for all available data. We included studies containing primary data on measles seroprevalence and excluded studies if they were clinical trials or brief reports, from only health-care workers, suspected measles cases, or only vaccinated persons. We extracted all available information on measles seroprevalence, study design, and seroassay protocol. We conducted a bias assessment based on multiple categories and classified each study as having low, moderate, severe, or critical bias. This review was registered with PROSPERO (CRD42022326075).
RESULTS
We identified 221 relevant studies across all World Health Organization regions, decades, and unique age ranges. The overall crude mean seroprevalence across all studies was 78.0% (SD: 19.3%), and the median seroprevalence was 84.0% (IQR: 72.8-91.7%). We classified 80 (36.2%) studies as having severe or critical overall bias. Studies from country-years with lower measles vaccine coverage or higher measles incidence had higher overall bias.
CONCLUSIONS
While many studies have substantial underlying bias, many studies still provide some insights or data that could be used to inform modelling efforts to examine measles dynamics and programmatic decisions to reduce measles susceptibility.
PubMed: 38932314
DOI: 10.3390/vaccines12060585 -
Vaccines May 2024Due to the COVID-19 pandemic, many children missed their routine vaccinations globally. There is insufficient evidence on the trends in vaccination coverage in the...
Due to the COVID-19 pandemic, many children missed their routine vaccinations globally. There is insufficient evidence on the trends in vaccination coverage in the private healthcare sector in South Africa. This study explored the changes in childhood vaccination patterns (non-COVID vaccines) in the private healthcare sector in South Africa using medicine claim data. Using the information on medication claims from a South African pharmaceutical benefit management (PBM) company, we performed a quantitative cross-sectional analysis comparing the period before (2018-2019) and during the COVID-19 pandemic (2020-2021). All patients who made claims within the study period were included. This study included 67,830 children aged two years and younger. In particular, from 2018 to 2021, boys (52%) outnumbered girls (48%). Pharmacists consistently held the predominant prescriber role before and during the COVID-19 pandemic. The proportion of children receiving non-COVID-19 vaccines was higher before the pandemic (60%) than during the pandemic (55%). Furthermore, there was a notable decline of 5% in measles vaccination rates during the children's first year of life, while a notable increase was observed for measles (5%), hepatitis A (7.7%), and the pentavalent vaccine (5%) during the second year of life. Governments and private healthcare providers must take action to enhance vaccination coverage rates for children in their first year of life to prevent a resurgence of vaccine-preventable diseases. The results obtained in this study underscore the significance of implementing vaccine catch-up campaigns to address missed vaccination opportunities arising from the impact of the COVID-19 pandemic. Moreover, pharmacists emerged as the predominant healthcare providers responsible for administering vaccinations within the private healthcare sector in South Africa, both prior and during the COVID-19 pandemic. Their pivotal role in the vaccination process warrants due recognition and should not be underestimated.
PubMed: 38932311
DOI: 10.3390/vaccines12060582 -
Vaccine Jun 2024Globally, migrant populations usually experience lower vaccine coverage than the general population. In Finland, the MMR vaccination coverage of Somalis has not been...
"If the nurse tells me this is a good thing, I trust her completely" - Exploring health system enablers of MMR vaccine uptake in the Finnish Somali community: A mixed method study.
BACKGROUND
Globally, migrant populations usually experience lower vaccine coverage than the general population. In Finland, the MMR vaccination coverage of Somalis has not been studied specifically, but existing evidence suggests that the MMR vaccination coverage is high. The aim of this study was to examine both vaccination coverage of Somali children and factors associated with the MMR vaccine uptake of Somali children living in Finland.
METHODS
Twenty-seven mothers and seventeen public health nurses were interviewed using a semi-structured interview protocol. Audio-recorded interviews were transcribed and translated and analysed thematically after coding. The personal identity code of Somali children born in 2015 and 2020 were extracted from the Population Information System (PIS), and their vaccination coverage data was extracted from the national vaccination register (NVR) to calculate MMR vaccination coverage for Somali children.
RESULTS
96 % of Somali children born in 2015 and 81 % of those born in 2020 received their MMR vaccination. In contrast, the national average MMR vaccine uptake for children born in 2015 was 95 %, while 94 % of those born in 2020 were vaccinated against MMR. Somali mothers had poor knowledge of the MMR vaccine and the diseases it protects against. Trust towards the Finnish healthcare system, perceived benefits of vaccinating, positive attitudes towards vaccines, nurses' systematic approach to vaccine introduction, and nurses taking into account the cultural background of the clients were recognised as enablers positively affecting MMR vaccination uptake.
CONCLUSION
Despite limited knowledge of vaccines, Somali immigrant mothers believe in the benefits of vaccination, and they displayed strong trust towards public health nurses. Further investigation is needed to understand why MMR vaccination coverage has declined among the younger Somali population.
PubMed: 38926069
DOI: 10.1016/j.vaccine.2024.06.054 -
Expert Review of Vaccines 2024The global measles incidence has decreased from 145 to 49 cases per 1 million population from 2000 to 2018, but evaluating the economic benefits of a second...
INTRODUCTION
The global measles incidence has decreased from 145 to 49 cases per 1 million population from 2000 to 2018, but evaluating the economic benefits of a second measles-containing vaccine (MCV2) is crucial. This study reviewed the evidence and quality of economic evaluation studies to guide MCV2 introduction.
METHODS
The systematic review of model-based economic evaluation studies was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search yielded 2231 articles, with 876 duplicates removed and 1355 articles screened, with nine studies included for final analysis.
RESULTS
Six studies reported a positive benefit-cost ratio with one resulting in net savings of $11.6 billion, and two studies estimated a 2-dose MMR vaccination program would save $119.24 to prevent one measles case, and a second dose could prevent 9,200 cases at 18 months, saving $548.19 per case. The most sensitive variables were the discount rate and vaccination administration cost.
CONCLUSIONS
Two MCV doses or a second opportunity with an additional dose of MCV were highly cost-beneficial and resulted in substantial cost savings compared to a single routine vaccine. But further research using high-quality model-based health economic evaluation studies of MCV2 should be made available to decision-makers.
PROSPERO REGISTRATION
CRD42020200669.
Topics: Humans; Cost-Benefit Analysis; Immunization Programs; Immunization, Secondary; Measles; Measles Vaccine; Measles-Mumps-Rubella Vaccine; Vaccination
PubMed: 38924461
DOI: 10.1080/14760584.2024.2367451