Measles-containing Vaccine Coverage Research Articles

Modeling the Cost of Vaccinating a Measles Zero-Dose Child in Zambia Using Three Vaccination Strategies.

Countries with moderate to high measles-containing vaccine coverage face challenges in reaching the remaining measles zero-dose children. There is growing interest in targeted vaccination activities to reach these children. We developed a framework for prioritizing districts for targeted measles and rubella supplementary immunization activities (SIAs) for Zambia in 2020, incorporating the use of the WHO's Measles Risk Assessment Tool (MRAT) and serosurveys. This framework was used to build a model comparing the cost of vaccinating one zero-dose child under three vaccination scenarios: standard nationwide SIA, targeted subnational SIA informed by MRAT, and targeted subnational SIA informed by both MRAT and measles seroprevalence data. In the last scenario, measles seroprevalence data are acquired via either a community-based serosurvey, residual blood samples from health facilities, or community-based IgG point-of-contact rapid diagnostic testing. The deterministic model found that the standard nationwide SIA is the least cost-efficient strategy at 13.75 USD per zero-dose child vaccinated. Targeted SIA informed by MRAT was the most cost-efficient at 7.63 USD per zero-dose child, assuming that routine immunization is just as effective as subnational SIA in reaching zero-dose children. Under similar conditions, a targeted subnational SIA informed by both MRAT and seroprevalence data resulted in 8.17-8.35 USD per zero-dose child vaccinated, suggesting that use of seroprevalence to inform SIA planning may not be as cost prohibitive as previously thought. Further refinement to the decision framework incorporating additional data may yield strategies to better target the zero-dose population in a financially feasible manner.

Second dose of measles-containing vaccine coverage and associated factors among children aged 24-36 months in Gondar city, Central Gondar, Northwest Ethiopia, 2023.

Measles caused 207,000 deaths worldwide in 2019. Ethiopia ranks among the top 10 countries in the world with the highest number of measles cases. However, the coverage of the second dose of measles-containing vaccine (MCV2) remains low. To increase coverage, the government of Ethiopia launched a nationwide measles vaccination campaign. Despite this intervention, the coverage is still below target, and there is scarce information in the study area. Therefore, this study aimed to assess MCV2 coverage and associated factors among children aged 24-36 months in Gondar city, Central Gondar, Northwest Ethiopia, 2023. A community-based cross-sectional study was conducted among 621 children aged 24-36 months using a systematic random sampling technique from 25 April to 25 May. A pre-tested, interviewer-administered, and structured questionnaire was used and collected using Kobo Toolbox and then transferred to Stata version 17 for further analysis. The binary logistic regression model was used to identify factors, and the presence of an association was declared using a p-value of <0.05. Similarly, an adjusted odds ratio with a 95% confidence interval was used to interpret the direction and strength of an association. A total of 621 children, with a response rate of 98.1%, participated in the study. The coverage of the second dose of MCV was 75.68% (95% CI: 72.1-78.9). The following factors were significantly associated with measles-containing vaccine second dose (MCV2) coverage: father as the household head (AOR: 3.06, 95% CI: 1.43-6.44), first birth order (AOR: 4.45, 95% CI: 1.21-16.3), four and above antenatal care (ANC) follow-ups (AOR: 5.18, 95% CI:1.62-16.5), postnatal care (PNC) service utilization (AOR: 2.57, 95% CI:1.27-5.15), at least two doses of vitamin A uptake (AOR: 6.39, 95% CI: 2.67-15.2), mothers having high awareness (AOR: 1.97, 95% CI:1.15-3.4), and good perception (AOR: 3.6, 95% CI: 2-6.47) about measles vaccination. The coverage of MCV2 in the study area is lower than the national and global target of above 95%. Head of household, birth order, ANC follow-up, PNC service utilization, vitamin A uptake, awareness, and perception of mothers about measles vaccination were significant factors for MCV2 coverage. Creating awareness, increasing the perception of mothers about measles vaccination, and strengthening the ANC and PNC services will increase the coverage.

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. During 2000-2019, estimated coverage worldwide with the first dose of measles-containing vaccine (MCV) increased from 72% to 86%, then declined to 81% in 2021 during the COVID-19 pandemic, representing the lowest coverage since 2008. In 2022, first-dose MCV coverage increased to 83%. Only one half (72) of 144 countries reporting measles cases achieved the measles surveillance indicator target of two or more discarded cases per 100,000 population in 2022. During 2021-2022, estimated measles cases increased 18%, from 7,802,000 to 9,232,300, and the number of countries experiencing large or disruptive outbreaks increased from 22 to 37. Estimated measles deaths increased 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 COVID-19 pandemic setbacks; however, coverage declined in low-income countries, and globally, years of suboptimal immunization coverage left millions of children unprotected. Urgent reversal of coverage setbacks experienced during the COVID-19 pandemic can be accomplished by renewing efforts to vaccinate all children with 2 MCV doses and strengthening surveillance, thereby preventing outbreaks and accelerating progress toward measles elimination.

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. We conducted a literature review by searching PubMed on 31 October 2021 to determine the scope of evidence for the expert-identified indicators. Studies were included if they contained evidence of an association between an indicator and CFR and were excluded if they were from non-human studies or reported non-original data. Included studies were assessed for study quality. Expert consultation identified five mechanisms in a conceptual framework of factors related to measles CFR. We identified 3772 studies for review and found 49 studies showing at least one significant association with CFR for 15 indicators (average household size, educational attainment, first- and second-dose coverage of measles-containing vaccine, human immunodeficiency virus prevalence, level of health care available, stunting prevalence, surrounding conflict, travel time to major city or settlement, travel time to nearest health care facility, under-five mortality rate, underweight prevalence, vitamin A deficiency prevalence, vitamin A treatment, and general malnutrition) and only non-significant associations for five indicators (antibiotic use for measles-related pneumonia, malaria prevalence, percent living in urban settings, pneumococcal conjugate vaccination coverage, vitamin A supplementation). Our study used expert consultation and a literature review to provide additional insights and a summary of the available evidence of these underlying mechanisms and indicators that could inform future measles CFR estimations.

China has the momentum to eliminate measles

China has the momentum to eliminate measles

Factors contributing to a measles outbreak in a hard-to-reach rural village in Xaisomboun Province, Lao People’s Democratic Republic

ObjectiveAn increase in measles cases was reported in the north-western of the Lao People's Democratic Republic beginning in January 2019, with outbreaks quickly spreading throughout the country. Following identification of two laboratory-confirmed cases in Xaisomboun Province, we conducted an outbreak investigation to identify factors contributing to the measles outbreak in hard-to-reach Village X.MethodsActive case-finding was undertaken at the provincial hospital and primary health care centre via a retrospective search through admission logbooks and house-to-house surveys in Village X and surrounding villages. Clinical samples were collected from suspected cases, and data were collected using a standard case investigation form. Vaccine coverage data were reviewed.ResultsOf the 40 suspected measles cases with rash onset during 12 February–27 April 2019, 83% (33/40) resided in Village X and 98% (39/40) were of Hmong–Lu Mien ethnicity. Ages ranged from 22 days to 5 years, with 70% (28) aged < 24 months. Almost half of cases aged 9 to < 18 months (5/11) and 67% (8/12) of cases aged 324 months had received a measles-containing vaccine (MCV). Reported MCV coverage in Xaisomboun for children aged < 1 year in 2017–2018 was < 50%. In 55% (22/40) of cases, case notification was delayed by 36 days. The final case classification comprised 10% laboratory-confirmed, 20% clinically compatible, 60% epidemiologically linked and 10% non-cases.DiscussionThis measles outbreak was likely associated with low immunization coverage, compounded by delays in reporting. Effective strategies are needed to address beliefs about and health literacy barriers to immunization and measles awareness. Such strategies may improve MCV coverage and early diagnosis, enabling timely public health interventions and reducing mortality and morbidity.

National and regional variations in timely adherence to recommended measles vaccination scheme in 2-years old in Switzerland, 2005–2019

BackgroundAlthough monitoring of vaccination program performance is usually evaluated by measurement of vaccine coverage, timely uptake is rarely part of this assessment. This study aims to examine the timeliness of the administration of a measles-containing-vaccine (MCV) for 2-year-old children between 2005 and 2019. MethodsWe used data from the Swiss National Vaccination Coverage Survey 2005–2019 for the study. We defined timely vaccinated as a vaccination administered within the recommended age specified in the Swiss National Vaccination Schedule, with an added tolerance period of 30.4 days for both MCV 1 and 2 doses. The median delay time was estimated by Kaplan-Meier survival curve and examined using log-rank test. A Cox hazard ratio was used to identify factors associated with delay. Results81% (95% CI:79–82%) of toddlers were timely vaccinated for MCV1 and 82% (95% CI:81–83%) for MCV2 in survey period 2017–2019. Between 2005 and 2019, the median age of vaccinated children ranged between 12.2 and 12.5 and 18.3–22.0 months for MCV1 and MCV2 with median delay of 44 and 38 days, respectively, at the national level. Children in the French-, Italian- and German-speaking regions were vaccinated earlier between 2005 and 2019 for MCV1 (vaccination coverage range before 10 months of age: 1.7–45.9%, 1.2–35.3% and 1.4–15.0%, respectively). Nationality, linguistic regions, and survey periods were the strongest predictive factors related to prolonged delay time. ConclusionOverall adherence to recommendations has improved over time, as MCV coverage has significantly increased over the years with differences across linguistic regions. Vaccinations were administered earlier and with shorter delay time.

Factors affecting poor measles vaccination coverage in sub-Saharan Africa with a special focus on Nigeria: a narrative review

Measles is a highly contagious infection that can cause severe illness in children. Vaccination is the primary means of controlling the infection, with elimination a possibility. However, the measles-containing vaccine coverage in sub-Saharan Africa (SSA) is 70% while that for Nigeria is 54% according to official estimates and 64.7% from household surveys. This review aims to identify factors that contribute to the poor coverage rate and proposes appropriate recommendations to address these factors. We conducted a comprehensive search of five databases (MEDLINE, Embase, Global Health, CINAHL Plus and PubMed) using the PICOTS (population, intervention, comparison, outcome, timing, study type) framework. The search was conducted in September 2017 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and inclusion criteria were studies conducted in SSA, that evaluated measles vaccine coverage gaps, evaluated strategies for improving measles vaccination coverage and were published in English. The database search yielded 23 publications. Several different factors influencing measles vaccine coverage were identified and were grouped into four main areas: immunization system, information and communication, family characteristics and parental attitudes and knowledge. Fears and misconceptions were common reasons for non-vaccination. Activities to improve vaccination coverage were identified, including structural reforms such as siting health centres within or proximal to target communities, improving female literacy and conducting measles vaccination campaigns. Multiple reasons for poor measles vaccination coverage were identified. Factors influencing the immunization system and information and communication factors can be fixed at the country level, but challenges relating to family characteristics and parental attitudes and knowledge require solutions adapted to the community of concern. However, vaccination campaigns are an effective means of improving vaccination coverage and they reduce geographic and socio-economic inequities.

Trends of the Global, Regional, and National Incidence of Measles, Vaccine Coverage, and Risk Factors in 204 Countries From 1990 to 2019.

BackgroundMeasles is a highly contagious disease that has caused global morbidity and mortality. Though great progress has been made in measles elimination, the resurgence of measles has been observed in recent years. As extant literature were mainly confined to data of local area, we conducted a systematic analysis to explore the trends of the incidence of measles, coverage rate, and the risk factors from 1990 to 2019 on global, regional, and national levels.MethodsData on cases of incidence, age standardized rate (ASR), vaccine coverage, and risk factors of measles were retrieved from the Global Burden of Disease (GBD) Study 2019 database. Estimated averaged percentage change (EAPC) of ASR was calculated to quantify the trends of measles incidence. Pearson correlation was applied to assess the association of EAPC and measles-containing vaccine coverage rate with socio-demographic index (SDI) in 2019, and the correlation between ASR and measles-containing vaccine coverage rate.ResultsGlobally, there was a significant decrease in the number (84.18%) and ASR (6.13%, 95% CI: 5.41–6.84%) of measles incidence from 1990 to 2019. More than 80% of incidence cases were attributed to children under 5 and the proportion was highest in low SDI region. Countries and territories with low ASRs are mostly clustered in North America, Southern Latin America, and Western Europe, whereas those with high ASRs are mainly clustered in Africa, East Asia, and South Asia. Lower SDI was associated with higher ASR and lower vaccine coverage rate. The more the SDI value was further away from 0.6, the smaller the absolute value did EAPC have. Child wasting accounted for the most measles-related death cases, followed by child underweight, child stunting, and vitamin A deficiency.ConclusionsMeasles eradication is feasible, but urgently demands political commitment, financial support, and public engagement. In the context of COVID-19 pandemic and the global resurgence of measles, surveillance systems and routine immunization programs should be improved, while vaccine hesitancy needs to be addressed.

Effect of evidence updates on key determinants of measles vaccination impact: a DynaMICE modelling study in ten high-burden countries

BackgroundModel-based estimates of measles burden and the impact of measles-containing vaccine (MCV) are crucial for global health priority setting. Recently, evidence from systematic reviews and database analyses have improved our understanding of key determinants of MCV impact. We explore how representations of these determinants affect model-based estimation of vaccination impact in ten countries with the highest measles burden.MethodsUsing Dynamic Measles Immunisation Calculation Engine (DynaMICE), we modelled the effect of evidence updates for five determinants of MCV impact: case-fatality risk, contact patterns, age-dependent vaccine efficacy, the delivery of supplementary immunisation activities (SIAs) to zero-dose children, and the basic reproduction number. We assessed the incremental vaccination impact of the first (MCV1) and second (MCV2) doses of routine immunisation and SIAs, using metrics of total vaccine-averted cases, deaths, and disability-adjusted life years (DALYs) over 2000–2050. We also conducted a scenario capturing the effect of COVID-19 related disruptions on measles burden and vaccination impact.ResultsIncorporated with the updated data sources, DynaMICE projected 253 million measles cases, 3.8 million deaths and 233 million DALYs incurred over 2000–2050 in the ten high-burden countries when MCV1, MCV2, and SIA doses were implemented. Compared to no vaccination, MCV1 contributed to 66% reduction in cumulative measles cases, while MCV2 and SIAs reduced this further to 90%. Among the updated determinants, shifting from fixed to linearly-varying vaccine efficacy by age and from static to time-varying case-fatality risks had the biggest effect on MCV impact. While varying the basic reproduction number showed a limited effect, updates on the other four determinants together resulted in an overall reduction of vaccination impact by 0.58%, 26.2%, and 26.7% for cases, deaths, and DALYs averted, respectively. COVID-19 related disruptions to measles vaccination are not likely to change the influence of these determinants on MCV impact, but may lead to a 3% increase in cases over 2000–2050.ConclusionsIncorporating updated evidence particularly on vaccine efficacy and case-fatality risk reduces estimates of vaccination impact moderately, but its overall impact remains considerable. High MCV coverage through both routine immunisation and SIAs remains essential for achieving and maintaining low incidence in high measles burden settings.

Surveillance and response to measles outbreaks in China, 2016-2020

Objective: To understand the epidemiological characteristics of measles outbreaks in China from 2016 to 2020 and related outbreak investigations and response performances. Methods: The information about the incidence of measles outbreaks, the investigation and response of measles outbreaks in 31 provinces from 2016 to 2020 were collected from Measles Surveillance System, and the incidence of suspected measles outbreaks detected through sporadic case finding during the same period according to the measles outbreak definition was analyzed. Results: From 2016 to 2020, a total of 344 measles outbreaks were reported nationwide, involving 1 886 measles cases. The median of intervals between the first case onsets and reported outbreaks ranged from 4 to 10 days, the median of the numbers of involved cases ranged from 2 to 3, and the median of the duration of the epidemic ranged from 8 to 13 days, and some outbreaks had long durations of 65,44,28,63 and 13 days. The top three provinces with high number of reported outbreaks were Gansu, Beijing and Shandong. Among the reported outbreaks, 115 occurred in communities/villages, accounting for the highest proportion. The genotype identification results indicated that all the outbreaks in 2016 were caused by measles virus H1, and the proportion of the outbreaks caused by measles virus H1 decreased year by year since then, which was 88.57% (31/35) in 2017, 85.00% (17/20) in 2018 and 15.79% (3/19) in 2019 respectively. There was no outbreak caused by measles H1 reported in 2020, the 4 isolates all belonged to genotype D8. Active case findings were conducted in local medical institutions for 313 outbreaks, and measles-containing vaccine coverage surveys were conducted for 266 outbreaks. From 2016 to 2020, a total of 919 suspected measles outbreaks were detected nationwide, involving 4 212 measles cases. The top three provinces with suspected measles outbreaks were Xinjiang, Gansu and Sichuan. The suspected measles outbreaks also mainly occurred in communities/villages (493). Conclusions: The number, scale and duration of measles outbreaks were gradually decreasing, the measles outbreaks at the community level can not be ignored, and the local H1 genotypes tend to be gradually replaced by other genotypes. Improving the sensitivity of outbreak surveillance, promoting vaccination, expanding the vaccine coverage, timely and effective response to the outbreaks are the focus of measles elimination in China in the future.

Measles epidemiology and vaccination coverage in Oromia Region, Ethiopia: Evidence from surveillance, 2011–2018

Despite a reported high coverage of measles-containing vaccine (MCV), low-income countries including, Ethiopia, have sustained high measles transmission with frequent outbreaks. We investigated the distribution of measles infection and vaccination in Oromia Regional State, Ethiopia. According to the World Health Organization (WHO) and the Ethiopian measles case classification guidelines, measles cases were classified as laboratory-confirmed, clinically compatible, and epidemiologically linked. We derived measles vaccination coverage estimates using reported measles vaccine efficacy and, the proportion of measles cases vaccinated with measles vaccine at least once from the surveillance data. We calculated measles effective reproduction number (Re) in the region. Almost twenty-five thousand measles cases were reported through the surveillance system, with more than 50% of the suspected and confirmed measles cases reported in 2015. Measles had sustained and high transmission rate with uneven distribution among the zones. Children between 1 and 4 years of age and MCV unvaccinated individuals were the most affected groups. In all the zones, the average surveillance-estimated MCV coverage among both infants and under-five children was significantly lower than the WHO recommended minimum 90% threshold herd-immunity. With this level of vaccination coverage, an infected case can transmit to more than four individuals. Nevertheless, the administrative coverage reports for the concurrent period were consistently above 90%. The estimated MCV coverage across the Oromia region was well below the recommended herd-immunity threshold. It partly explains the apparent mismatch of sustained measles transmission and outbreaks despite the very high administrative coverage estimates. Oromia regional health bureau, in collaboration with key stakeholders, should make a concerted effort to increase the effective-coverage of MCV to at least 90%. Additionally, multiple-dose MCV has to be scaled-up and accompanied with appropriate geographic and age targeting using evidence from surveillance data. Immediate programmatic action is needed to improve the quality of measles surveillance.

Evaluation of measles vaccination coverage in Lincang City, Yunnan Province, China

ABSTRACT Background: Lincang City in Yunnan Province on the China-Myanmar border, has reached the World Health Organization recommended coverage (95%) for measles-containing vaccine (MCV), but measles outbreaks still occur. We conducted a survey in Lincang City to determine the measles vaccination status of children on the China–Myanmar border. Methods: We used multistage sampling among children aged 8–83 months. Information on measles vaccination status was obtained from the child’s vaccination certificate, and serum samples were tested using commercially available ELISA kits. Results: A total of 938 children were surveyed. The vaccination coverage rate was 98.9% (95% CI: 98.2–99.6%) for measles–containing vaccine dose 1 (MCV1), and 95.8% (95% CI:94.9–96.7%) for measles–containing vaccine dose 2 (MCV2). The timely vaccination coverage rate was 52.0% (95% CI:48.8–55.2%) for MCV1, and 74.1% (95% CI: 82.9–89.0%) for MCV2. The timely-and–complete vaccination coverage rate was 41.0% (95% CI: 36.7–45.3%). The median delay period was 33 (95% CI: 27–39) days for MCV1, and 196 (95% CI: 146–246) days for MCV2. The seropositivity rate in children aged less than 7 years was 94.0% (95% CI: 92.5–95.5%) with a geometric mean titer of 1210.1 mIU/mL. Conclusions: The MCV coverage was high, but timely and timely-and-complete vaccination coverage were low and insufficient to prevent measles outbreaks. It is necessary to add the timely and timely-and-complete vaccination coverage as indicators of vaccination to provide a more complete picture of measles immunization status.

Measles outbreak in complex emergency: estimating vaccine effectiveness and evaluation of the vaccination campaign in Borno State, Nigeria, 2019

BackgroundFrom January to May 2019, large measles outbreaks affected Nigeria. Borno state was the most affected, recording 15,237 suspected cases with the state capital of Maiduguri having 1125 cases investigated and line-listed by March 2019. In Borno state, 22 of the 27 Local Government Areas (LGAs or Districts), including 37 internally displaced persons (IDPs) camps were affected. In response to the situation, an outbreak response immunization (ORI) campaign was conducted in the 13 most affected LGAs. In addition to conventional vaccination teams, special teams were deployed in security compromised areas, areas with migrants, and for nomadic and IDPs. Here we describe the outbreak and the ORI campaign. We also assess the measles-containing vaccine (MCV) coverage and vaccine effectiveness (VE) in order to quantify the population-level impact.MethodsWe reviewed the ORI activities, and conducted an analysis of the surveillance and the outbreak investigation reports. We assessed VE of MCV by applying the screening-method. Sensitivity analyses were also conducted to assess the effect of final classification of cases on the VE of MCV. The MCV coverage was assessed by a post-campaign coverage survey after completion of the ORI through a quantitative survey in the 12 LGAs that were accessible.ResultsOf the total 15,237 reported measles cases, 2002 cases were line-listed and investigated, and 737 were confirmed for measles by week 9 of 2019. Of the investigated cases 67.3% (n = 1348) were between 9 and 59 months of age. Among the 737 confirmed cases, only 9% (n = 64) stated being vaccinated with at least 1 dose of MCV. The overall VE for MCV was 98.4% (95%CI: 97.8–98.8). No significant differences were observed in the VE estimates of lab-confirmed and epi-linked cases when compared to the original estimates. The aggregated weighted vaccination coverage was 85.7% (95% CI: 79.6–90.1).ConclusionThe experience in Borno demonstrates that adequate VE can be obtained in conflict-affected areas. In complex emergencies affected by measles outbreaks, health authorities may consider integration with other health strategies and the engagement of security personnel as part of the ORI activities.

The association between the density of vaccination workers and immunization coverage in Zhejiang province, East China

ABSTRACT Background: We aimed to evaluate whether the density of vaccination workers was associated with the immunization coverage in Zhejiang province. Methods: The immunization coverage of measles-containing vaccine (MCV), the third dose of diphtheria, tetanus, and pertussis combined vaccine (DTP3), and the third dose of poliomyelitis vaccine (PV3) was selected as the dependent variables. Immunization coverage data of children aged 13–23 months were taken from the Zhejiang immunization information system (ZJIIS). The aggregate density of vaccination workers was an independent variable in one set of regressions, while the full-time and part-time vaccination workers were adopted separately in other sets. Results: The density of total vaccination workers was positively and significantly associated with the immunization coverage (MCV: AOR = 3.36; DTP3: AOR = 2.68; PV3: AOR = 2.37). However, when the effects of full-time vaccination workers and part-time vaccination workers were assessed separately, we only found that the density of full-time vaccination workers was positively and significantly associated with the immunization coverage (MCV: AOR = 5.59; DTP3: AOR = 4.13; PV3: AOR = 3.28). The proportion of migrant children < 7 years and Land area were found as negative and significant factors for immunization coverage. Conclusions: A higher density of vaccination workers could improve the availability of vaccination services and immunization coverage. We recommended that government or other non-government organization should, apart from vaccine-related assistance, focus their efforts on human resources for vaccination.

Association between live childhood vaccines and COVID-19 outcomes: a national-level analysis.

We investigated whether countries with higher coverage of childhood live vaccines [BCG or measles-containing-vaccine (MCV)] have reduced risk of coronavirus disease 2019 (COVID-19)-related mortality, while accounting for known systems differences between countries. In this ecological study of 140 countries using publicly available national-level data, higher vaccine coverage, representing estimated proportion of people vaccinated during the last 14 years, was associated with lower COVID-19 deaths. The associations attenuated for both vaccine variables, and MCV coverage became no longer significant once adjusted for published estimates of the Healthcare access and quality index (HAQI), a validated summary score of healthcare quality indicators. The magnitude of association between BCG coverage and COVID-19 death rate varied according to HAQI, and MCV coverage had little effect on the association between BCG and COVID-19 deaths. While there are associations between live vaccine coverage and COVID-19 outcomes, the vaccine coverage variables themselves were strongly correlated with COVID-19 testing rate, HAQI and life expectancy. This suggests that the population-level associations may be further confounded by differences in structural health systems and policies. Cluster randomised studies of booster vaccines would be ideal to evaluate the efficacy of trained immunity in preventing COVID-19 infections and mortality in vaccinated populations and on community transmission.

Trends in the uptake of pediatric measles-containing vaccine in the United States: A Disneyland effect?

BackgroundThe measles outbreak that began in December 2014 at the California Disneyland theme park in the United States (U.S.) received a high amount of media attention. Media attention can influence health-related behaviors. We investigated the effect of the Disneyland outbreak on measles-containing vaccine (MCV) uptake among U.S. children. MethodsWe used 2012–2017 National Immunization Survey-Child (NIS-Child) data to examine MCV uptake among U.S. children by 19 months of age. We classified MCV coverage among birth cohorts as exposed based on age at the time of the outbreak. A difference-in-differences design with adjustment for categorical birth cohort was implemented in base models to estimate the exposure effect on the outcomes, ≥1-dose MCV coverage or age at first MCV dose, with pneumococcal conjugate vaccination as a control. Primary analyses included this model adjusted for geographic region, maternal education, race/ethnicity, household income, and insurance status, and an exposure-interaction term with maternal education. All analyses included sampling weights. ResultsThe study population represented 34,471,357 children. In base models, the Disneyland outbreak was associated with a 1.0% (95% CI: 0.2%, 1.8%) increase in ≥1-dose MCV coverage and a 6.6 (95% CI: 4.8, 8.5)-day decrease in MCV administration age. In primary analyses, the outbreak was associated with a 3.9% (95% CI: 3.1%, 4.8%) increase in ≥1-dose MCV coverage among children of college-educated mothers, and a 3.2% (95% CI: 0.6%, 5.9%) decrease among children of mothers earning less than a high school degree. Decreases in MCV administration age ranging from 5.9 (95% CI: 3.3, 8.5) to 9.1 (95% CI: 6.8, 11.4) days were observed across maternal education categories. ConclusionsThe Disneyland outbreak was associated with differential effects on MCV coverage by maternal education and decreases in MCV administration age among U.S. children. These findings may provide useful insights to inform methods to address pediatric MCV undervaccination.

Measles vaccination among children in border areas of Yunnan Province, Southwest China

BackgroundBorder areas are at high risk of measles epidemics. This study aimed to evaluate the effectiveness of the implementation of the routine two-dose measles containing vaccine (MCV) program in border counties of Southwest China.MethodsData used in the study were derived from a cross-sectional survey among 1,467 children aged 8 to 84 months from five border counties of Yunnan Province, Southwest China in 2016. The participants were recruited using a multistage sampling method. Primary guardians of the children were interviewed to collect information on vaccination history, socio-economic status, and knowledge about immunization. Both coverage and timely coverage for the first (MCV1) and the second (MCV2) dose of MCV were calculated. The Kaplan-Meier method was performed to estimate the cumulative coverage of MCV, and Log-rank tests were adopted to compare the differences across counties and birth cohorts. Univariate and multivariate logistic regression models were used to investigate the predictors of delayed MCV1 vaccination.ResultsThe coverage for MCV1 and MCV2 were 97.5% and 93.4%, respectively. However, only 63.8% and 84.0% of the children received MCV1 or MCV2 on time. Significant differences in the cumulative coverage were detected across counties and birth cohorts. Results of the multivariate logistic regression analysis indicated that children whose primary guardian knew the schedule of MCV were less likely to receive MCV1 late (OR = 0.63, P<0.01). For the guardians, doctors at vaccination units were the primary and also the most desired source of vaccination information.ConclusionsAlthough the coverage for MCV is high in border areas of Southwest China, the timeliness of MCV vaccination seems suboptimal. Tailored information from local health professionals may help to reduce untimely vaccination.

Age-appropriate vaccination coverage and its determinants for the polio containing vaccine 1-3 and measles-containing vaccine doses in Zhejiang province, China: A community-based cross-sectional study

ABSTRACT Background: This study aimed to evaluate the age-appropriate coverage and its associated risk factors for the primary vaccination of Polio containing vaccine (PCV) and measles-containing vaccine (MCV) through the secondary use of the 2018 Zhejiang provincial coverage survey among children aged 12–23 months. Methods: Data were collected through structured pre-tested Chinese version questionnaire by face-to-face interview among 770 mothers whose children aged 12–23 months. Age-appropriate vaccination coverage was measured using Chinese vaccination schedule recommendation. Bivariate and multivariate logistic regression models were adopted to identify determinants of the age-inappropriate vaccination. Results: The age-appropriate vaccination coverage of PCV1, PCV2, PCV3, and MCV was 88.8%, 80.8%, 73.6%, and 75.7%, respectively. The risk factors associated with the age-inappropriate vaccination of PCV 1–3 dose and MCV included child’s gender, birthplace, living area, maternal education level, immigration status, monthly household income, participation of the pregnant women’s seminar, antenatal care follow-up, knowledge on vaccination. Conclusion: The proportions of age-appropriate vaccination coverage were low compared with the up-to-date coverage. Modifiable factors were associated with age-inappropriate vaccinations. Vaccination interventions should consider identified modifiable factors to improve age-appropriate vaccination coverage.

Epidemiology of measles in Oromia region, Ethiopia, 2007-2016.

Introductionmeasles is the leading vaccine preventable childhood disease designated for elimination by WHO. More than 20 million people are affected by measles each year, particularly in Africa and Asia. With annual outbreaks reported from Ethiopia´s Oromia region. We analyzed measles containing vaccine coverage (MCV), measles cases and measles deaths over a 10-year period (2007-2016).Methodswe reviewed Oromia measles surveillance data and first-dose measles containing vaccine (MCV1) administrative coverage. Descriptive statistics and multivariable logistic regression were performed to assess variables associated with measles death. Additional spatial mapping was performed to visually display key areas of measles case distribution in Oromia.Resultsa total of 26,908 measles suspect cases were identified, of which 18,223 (68%) were confirmed. A median age of 6 years (IQ range 0.5-71 years) and 288 deaths were observed. Among the total cases, 29% were unvaccinated and 46% had unknown vaccination status. The highest IR was seen in Guji zone (IR=190/100,000 population) among 1-4 years, with a majority from rural areas. Risk factors associated with death include age <5 years (AOR=1.82, CI: 1.42-2.33), unvaccinated status (AOR=1.44, CI: 1.06-1.95) and inpatient treatment (AOR=2.12, CI: 1.58-2.85). Of 8,732 measles IgM negative/indeterminate specimens, 10.5% tested positive for rubella specific IgM.Conclusionoutbreaks of measles are an ongoing public health concern in the Oromia region. Children aged 1-15 years remain at high risk for contracting measles in the region. We recommend strengthening routine immunization to reach all children, especially in rural areas and that the measles-rubella (MR) vaccine be considered.