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Epidemiology and Infection May 2024Until the early twentieth century, populations on many Pacific Islands had never experienced measles. As travel to the Pacific Islands by Europeans became more common,...
Until the early twentieth century, populations on many Pacific Islands had never experienced measles. As travel to the Pacific Islands by Europeans became more common, the arrival of measles and other pathogens had devastating consequences. In 1911, Rotuma in Fiji was hit by a measles epidemic, which killed 13% of the island population. Detailed records show two mortality peaks, with individuals reported as dying solely from measles in the first and from measles and diarrhoea in the second. Measles is known to disrupt immune system function. Here, we investigate whether the pattern of mortality on Rotuma in 1911 was a consequence of the immunosuppressive effects of measles. We use a compartmental model to simulate measles infection and immunosuppression. Whilst immunosuppressed, we assume that individuals are vulnerable to dysfunctional reactions triggered by either (i) a newly introduced infectious agent arriving at the same time as measles or (ii) microbes already present in the population in a pre-existing equilibrium state. We show that both forms of the immunosuppression model provide a plausible fit to the data and that the inclusion of immunosuppression in the model leads to more realistic estimates of measles epidemiological parameters than when immunosuppression is not included.
Topics: Measles; Humans; Disease Outbreaks; Child; Infant; Child, Preschool; Adolescent; Fiji; History, 20th Century; Male; Adult; Young Adult; Female; Middle Aged; Immunosuppression Therapy
PubMed: 38736255
DOI: 10.1017/S095026882400075X -
Microbes and Infection Feb 2018
Topics: Cause of Death; Child, Preschool; Developing Countries; Humans; Infant; Infant, Newborn; Measles; Measles Vaccine; Subacute Sclerosing Panencephalitis; United States; Vaccination; World Health Organization
PubMed: 29126876
DOI: 10.1016/j.micinf.2017.10.004 -
The Lancet. Global Health Aug 2023WHO recommends at least 95% population coverage with two doses of measles-containing vaccine (MCV). Most countries worldwide use routine services to offer a first dose...
Health effects of routine measles vaccination and supplementary immunisation activities in 14 high-burden countries: a Dynamic Measles Immunization Calculation Engine (DynaMICE) modelling study.
BACKGROUND
WHO recommends at least 95% population coverage with two doses of measles-containing vaccine (MCV). Most countries worldwide use routine services to offer a first dose of measles-containing vaccine (MCV1) and later, a second dose of measles-containing vaccine (MCV2). Many countries worldwide conduct supplementary immunisation activities (SIAs), offering vaccination to all people in a specific age range irrespective of previous vaccination history. We aimed to estimate the relative effects of each dose and delivery route in 14 countries with high measles burden.
METHODS
We used an age-structured compartmental dynamic model, the Dynamic Measles Immunization Calculation Engine (DynaMICE), to assess the effects of different vaccination strategies on measles susceptibility and burden during 2000-20 in 14 countries with high measles incidence (containing 53% of the global birth cohort and 78% of the global measles burden). Country-specific routine MCV1 and MCV2 coverage data during 1980-2020 were obtained from the WHO and UNICEF Estimates of National Immunization Coverage database for all modelled countries and SIA data were obtained from the WHO summary of measles and rubella SIAs. We estimated the incremental health effects of different vaccination strategies using prevented cases of measles and deaths from measles and their efficiency using the incremental number needed to vaccinate (NNV) to prevent an additional measles case.
FINDINGS
Compared with no vaccination, MCV1 implementation was estimated to have prevented 824 million cases of measles and 9·6 million deaths from measles, with a median NNV of 1·41 (IQR 1·35-1·44). Adding routine MCV2 to MCV1 was estimated to have prevented 108 million cases and 404 270 deaths, whereas adding SIAs to MCV1 was estimated to have prevented 256 million cases and 4·4 million deaths. Despite larger incremental effects, adding SIAs to MCV1 (median incremental NNV 6·02, 5·30-7·68) showed reduced efficiency compared with adding routine MCV2 (5·41, 4·76-6·11).
INTERPRETATION
Vaccination strategies, including non-selective SIAs, reach a greater proportion of children who are unvaccinated and reduce measles burden more than MCV2 alone, but efficiency is lower because of the wide age range targeted by SIAs. This analysis provides information to help improve the health effects and efficiency of measles vaccination strategies. The interplay between MCV1, MCV2, and SIAs should be considered when planning future measles vaccination strategies.
FUNDING
Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation.
Topics: Child; Humans; Infant; Immunization Schedule; Immunization Programs; Immunization; Measles Vaccine; Measles; Vaccination
PubMed: 37474227
DOI: 10.1016/S2214-109X(23)00220-6 -
The Lancet. Global Health Apr 2023To understand the current measles mortality burden, and to mitigate the future burden, it is crucial to have robust estimates of measles case fatalities. Estimates of...
BACKGROUND
To understand the current measles mortality burden, and to mitigate the future burden, it is crucial to have robust estimates of measles case fatalities. Estimates of measles case-fatality ratios (CFRs) that are specific to age, location, and time are essential to capture variations in underlying population-level factors, such as vaccination coverage and measles incidence, which contribute to increases or decreases in CFRs. In this study, we updated estimates of measles CFRs by expanding upon previous systematic reviews and implementing a meta-regression model. Our objective was to use all information available to estimate measles CFRs in low-income and middle-income countries (LMICs) by country, age, and year.
METHODS
For this systematic review and meta-regression modelling study, we searched PubMed on Dec 31, 2020 for all available primary data published from Jan 1, 1980 to Dec 31, 2020, on measles cases and fatalities occurring up to Dec 31, 2019 in LMICs. We included studies that previous systematic reviews had included or which contained primary data on measles cases and deaths from hospital-based, community-based, or surveillance-based reports, including outbreak investigations. We excluded studies that were not in humans, or reported only data that were only non-primary, or on restricted populations (eg, people living with HIV), or on long-term measles mortality (eg, death from subacute sclerosing panencephalitis), and studies that did not include country-level data or relevant information on measles cases and deaths, or were for a high-income country. We extracted summary data on measles cases and measles deaths from studies that fitted our inclusion and exclusion criteria. Using these data and a suite of covariates related to measles CFRs, we implemented a Bayesian meta-regression model to produce estimates of measles CFRs from 1990 to 2019 by location and age group. This study was not registered with PROSPERO or otherwise.
FINDINGS
We identified 2705 records, of which 208 sources contained information on both measles cases and measles deaths in LMICS and were included in the review. Between 1990 and 2019, CFRs substantially decreased in both community-based and hospital-based settings, with consistent patterns across age groups. For people aged 0-34 years, we estimated a mean CFR for 2019 of 1·32% (95% uncertainty interval [UI] 1·28-1·36) among community-based settings and 5·35% (5·08-5·64) among hospital-based settings. We estimated the 2019 CFR in community-based settings to be 3·03% (UI 2·89-3·16) for those younger than 1 year, 1·63% (1·58-1·68) for age 1-4 years, 0·84% (0·80-0·87) for age 5-9 years, and 0·67% (0·64-0·70) for age 10-14 years.
INTERPRETATION
Although CFRs have declined between 1990 and 2019, there are still large heterogeneities across locations and ages. One limitation of this systematic review is that we were unable to assess measles CFR among particular populations, such as refugees and internally displaced people. Our updated methodological framework and estimates could be used to evaluate the effect of measles control and vaccination programmes on reducing the preventable measles mortality burden.
FUNDING
Bill & Melinda Gates Foundation; Gavi, the Vaccine Alliance; and the US National Institutes of Health.
Topics: Humans; Developing Countries; Bayes Theorem; Measles; Vaccination; Income; Global Health
PubMed: 36925172
DOI: 10.1016/S2214-109X(23)00043-8 -
Medicinski Glasnik : Official... Feb 2020Aim To present combined measles cases data and phylogenetic analysis of the virus circulated in 2018 in the Federation of Bosnia and Herzegovina (FB&H, the entity of...
Epidemiology of measles cases and phylogenetic analysis of the virus circulated in the Federation of Bosnia and Herzegovina during 2018: implications for elimination efforts.
Aim To present combined measles cases data and phylogenetic analysis of the virus circulated in 2018 in the Federation of Bosnia and Herzegovina (FB&H, the entity of Bosnia and Herzegovina), in order to analyse endemic transmission patterns of circulating strains and its implications for elimination efforts. Methods The data were derived from epidemiological case investigations and laboratory diagnoses based on serology, molecular detection and genotyping of the measles virus. Results During 2018 16 measles cases were reported in FB&H, of which five were classified as laboratory confirmed cases, one was an epidemiologically linked case and 10 were clinically compatible cases. Among them 12 (75.00%) cases were unvaccinated or had unknown vaccination status. The most affected population was up to 14 years of age (13/16; 81.25%). None of the cases was fully vaccinated. Viruses of other genetic lineages had been introduced in FB&H in the recent period. Two virus lineages of genotype B3 were identified. Phylogenetic analysis indicated the presence of a unique sequence of measles B3 virus in FB&H (Sarajevo). Conclusion Further strengthening of measles surveillance system and renewed efforts to increase vaccination levels are necessary to prevent disease and for elimination setting.
Topics: Bosnia and Herzegovina; Genotype; Humans; Measles; Measles virus; Molecular Epidemiology; Phylogeny
PubMed: 31359742
DOI: 10.17392/1054-20 -
The Pan African Medical Journal 2022measles is a highly contagious viral disease. Since 2011, the Democratic Republic of Congo (DR Congo) has had the first dose measles vaccination coverage of less than...
INTRODUCTION
measles is a highly contagious viral disease. Since 2011, the Democratic Republic of Congo (DR Congo) has had the first dose measles vaccination coverage of less than 80% according to the World Health Organization - United Nations International Children's Emergency Fund (WHO-UNICEF) coverage estimates, and measles mass vaccination coverage of less than the required coverage level of 95% by survey. Starting in August 2018, the country experienced an increase in measles case reports which continued through to early 2020. Epidemiological aspects of the outbreak are described in this article.
METHODS
we analysed aggregate weekly passive surveillance data from the DR Congo for the years 2018 - 2020 to understand the trends of occurrence of suspected measles cases. We also analysed the measles case-based surveillance database to understand the epidemiological characteristics of confirmed cases of measles and rubella during the same period of time.
RESULTS
a total of 458,156 suspected measles cases and 8,127 deaths were reported between 1 January 2018 and 31 December 2020, with the majority of cases and deaths reported in 2019. Only 2.9% of these cases were reported through the case-based surveillance system, with 31,639 cases being confirmed as measles by the laboratory, by epidemiological linkage and on clinical compatibility. Children less than 5 years of age were most affected with a cumulative incidence of 960 cases per 1,000,000 inhabitants. Only 41% of the confirmed cases were vaccinated. Maindombe and Tshopo provinces had the highest cumulative incidence levels. There was a distinct geographic progression of the outbreak between provinces during the course of the three years. A total of 1760 lab confirmed rubella cases were confirmed in various provinces among the cases investigated with blood specimens, 93% of whom were less than 15 years of age.
CONCLUSION
the recent gaps in vaccination coverage, the age pattern of confirmed cases and the lack of vaccination history in the majority of cases is suggestive of failure to vaccinate as the likely cause of this large and protracted outbreak. Efforts to improve vaccination coverage and the measles surveillance system are needed in order to prevent the occurrence of future outbreaks and to avert measles-related deaths.
Topics: Humans; Child; Democratic Republic of the Congo; Measles; Disease Outbreaks; Rubella; Vaccination Coverage
PubMed: 36405650
DOI: 10.11604/pamj.2022.42.282.34410 -
British Medical Journal Jun 1980
Topics: Child; Humans; Measles; Measles Vaccine; United Kingdom; United States
PubMed: 7427185
DOI: 10.1136/bmj.280.6231.1616-c -
Indian Journal of Medical Ethics 2007
Topics: Developing Countries; Drug Costs; Health Services Needs and Demand; Humans; Infant; Measles; Measles Vaccine; Medical Indigency
PubMed: 18630363
DOI: 10.20529/IJME.2007.018 -
BMC Public Health Apr 2021To understand operational challenges involved with responding to US measles outbreaks in 2017-19 and identify applicable lessons in order to inform preparedness and...
BACKGROUND
To understand operational challenges involved with responding to US measles outbreaks in 2017-19 and identify applicable lessons in order to inform preparedness and response operations for future outbreaks, particularly with respect to specific operational barriers and recommendations for outbreak responses among insular communities.
METHODS
From August 2019 to January 2020, we conducted 11 telephone interviews with 18 participants representing state and local health departments and community health centers that responded to US measles outbreaks in 2017-19, with a focus on outbreaks among insular communities. We conducted qualitative, thematic coding to identify and characterize key operational challenges and lessons identified by the interviewees.
RESULTS
We categorized principal insights into 5 topic areas: scale of the response, vaccination operations, exclusion policies, community engagement, and countering anti-vaccine efforts. These topics address resource-intensive aspects of these outbreak responses, including personnel demands; guidance needed to support response operations and reduce transmission, such as excluding exposed or at-risk individuals from public spaces; operational challenges and barriers to vaccination and other response activities; and effectively engaging and educating affected populations, particularly with respect to insular and vulnerable communities.
CONCLUSIONS
Measles outbreak responses are resource intensive, which can quickly overwhelm existing public health capacities. Early and effective coordination with trusted leaders and organizations in affected communities, including to provide vaccination capacity and facilitate community engagement, can promote efficient response operations. The firsthand experiences of public health and healthcare personnel who responded to measles outbreaks, including among insular communities, provide evidence-based operational lessons that can inform future preparedness and response operations for outbreaks of highly transmissible diseases.
Topics: Disease Outbreaks; Epidemics; Humans; Measles; Measles Vaccine; Public Health; Vaccination
PubMed: 33845797
DOI: 10.1186/s12889-021-10652-9 -
Current Opinion in Virology Apr 2020Recently, a lateral flow rapid diagnostic test (RDT) with good accuracy has been described. This test enables measles specific IgM antibody detection in serum, capillary... (Review)
Review
Recently, a lateral flow rapid diagnostic test (RDT) with good accuracy has been described. This test enables measles specific IgM antibody detection in serum, capillary blood and oral fluid. RDTs have the potential to transform measles surveillance by allowing real-time case confirmation outside of central/regional laboratories and by facilitating a timely public health response. Measles virus genes can also be amplified and sequenced consistently from dried IgM-positive RDTs stored outside of cold chain, which will enable more complete virologic surveillance. Critical questions remain regarding operational use of RDTs as part of global measles surveillance. Projects to evaluate RDT use as part of national surveillance programs and to commercialize the RDT are underway.
Topics: Diagnostic Tests, Routine; Epidemiological Monitoring; Global Health; Humans; Measles; Measles virus
PubMed: 32615510
DOI: 10.1016/j.coviro.2020.05.007