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Prior to the age of measles vaccination, infants are believed to be protected against measles by passively transferred maternal antibodies. However, the quantity and quality of such protection have not been well established in the Indian setting. We undertook this study to characterize the transfer and decline in maternal anti-measles antibodies among infants, and determine their susceptibility to measles. In this population-based, birth-cohort study, we enrolled pregnant women and their newborn infants, from a catchment area of 30 Anganwadis in Chandigarh, India. We collected maternal blood at delivery, and infant blood samples at birth, and 3, 6, and 9 months of age. Anti-measles IgG antibodies were measured using quantitative ELISA. We assessed antibody decline using log-linear models. In total, 428 mother-infant dyads were enrolled, and data from 413 dyads were analyzed. At birth, 91.5% (95% CI: 88.8, 94.2) of infants had protective antibody levels, which declined to 26.3% (95% CI: 21.0%, 31.9) at 3 months, 3.4% (95% CI: 0.9, 5.9) at 6 months, and 2.1% (95% CI: 0.1, 4.1) at 9 months. Younger mothers transferred lower levels of antibodies to their infants. We concluded that the majority of infants are susceptible to measles as early as three months of age, much earlier than their eligibility to receive measles vaccination., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Mathew et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Measles continues to result in focal outbreaks in India, despite over three decades of universal infant vaccination. The aims of this study were to examine measles immunity in the population of Chandigarh, India, and to compare immunity by vaccination vs. natural infection. In a cross-sectional study of individuals 1-60 years selected from 30 communities within Chandigarh during 2017-2018, measles immunity was assessed using serological surveys. Seropositivity was compared across demographic groups, and by prior history of vaccination and natural history of infection. Among those 1-20 years old, measles seropositivity, and histories of measles vaccination or prior measles diagnosis were separately assessed as outcomes in logistic regression models, with demographic factors as independent variables. Among 1690 participants, 94% were seropositive, and 6% had borderline or negative antibody levels. Of those positive, 30% had prior vaccination, 16% had a history of natural infection, and 54% had an unknown history. Over 50% of individuals among those >20 years old, had unknown history of immunity. In the multivariable regression models, vaccination was more common in younger ages (P < .0001), and in males compared to females (P = .0220), and in those with more education (P < .0001). The majority of the population was seropositive, and seropositivity increased with age. Older age groups were more likely to be protected because of previous natural infection, whereas younger age groups were protected by vaccination. There was inequity in vaccination coverage by gender, and maternal education status.

Measles affects those of lower socioeconomic status disproportionately. This study evaluated the impact of measles vaccination on antibody titers 3 months after vaccination across different socioeconomic groups, with a focus on caste. In total, 169 infants in Chandigarh, India, had serum samples collected immediately prior to vaccination at 9 months of age and 3 months later. Overall, 126 infants (76%) were seropositive (antibody titers > 12 mIU/mL), 26 (16%) were borderline (8-12 mIU/mL), and 14 (8%) were seronegative (< 8 mIU/mL). Seropositivity (versus borderline/seronegative infants) was 0.78 times as high among individuals from the historically marginalized scheduled castes/scheduled tribes compared with the others caste grouping (95% CI, 0.62-0.98). Antibody response was not tied to anthropometric measures but was attenuated among scheduled castes/scheduled tribes with higher incomes. This study provides observational evidence that social structures can be associated with individual immune responses.

Introduction: Some Muslim religious councils in Indonesia have ruled that measles vaccines contain haram (i.e., forbidden materials). This study evaluates the changes in measles vaccination coverage between 1991 and 2017 and compares vaccination coverage between Muslims and non-Muslims in Indonesia., Methods: A total of 7 cross-sectional in-person surveys of mothers in 1991-2017 in Indonesia were analyzed in 2019. Participants were asked about religion in 1991-2007, and 100 data sets of religion were imputed for 2012 and 2017. In this multiple imputation analysis, binomial regression models output prevalence differences adjusted for wealth, education, child's sex, and mother's age. A quadratic term for year (year X year) and an interaction term between year and religion evaluated changes in vaccination over time by religion., Results: The 7 data sets included 23,106 children aged 12-23 months, with the proportion of those who were Muslims ranging between 85% and 89% across the survey years. Between 1991 and 2017, measles vaccination coverage increased from 57% to 79% among non-Muslims and from 59% to 79% among Muslims. In the multivariable regression model, measles vaccination coverage increased by 1.6% each year (with a quadratic term of -0.05%, indicating some leveling over time). At baseline in 1991, non-Muslims had a vaccination coverage of 6.2% higher than that of Muslims, but this disparity decreased by -0.2% each year., Conclusions: Measles vaccination increased in both Muslims and non-Muslims in Indonesia but has stagnated in recent years. Because of increased attention among Muslim groups on haram materials in vaccines since 2017, future studies should continue to examine the relationship between religion and vaccine uptake in Indonesia., Supplement Information: This article is part of a supplement entitled Global Vaccination Equity, which is sponsored by the Global Institute for Vaccine Equity at the University of Michigan School of Public Health., (Copyright © 2020 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Although global progress in measles control has been realized, achieving elimination has proven difficult in many regions of the world. China has adopted a goal of measles elimination but recent outbreaks predominantly affecting children <8 months who are ineligible for vaccination and incompletely protected by maternal antibodies has impeded progress. We assess the cost-effectiveness of adding an initial measles vaccine dose in China to earlier than the currently recommended 8 months of age., Methods: We conducted a cost-utility analysis comparing the costs and health benefits associated with adding a measles vaccine dose to the routine schedule at 4, 5, 6 or 7 months compared to the current recommendation for the first dose at age 8 months. A decision analytic model was developed in Microsoft Excel, including five non-severe and two fatal health outcomes associated with measles infection. Model parameters were informed by the literature and surveillance data. Future costs and health benefits were discounted at 3%. Primary outcomes included costs, Quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) over a lifetime time horizon., Results: Lowering the recommended age for initiating the measles vaccination series to address susceptibility in children <8 months provided incremental health gains compared to minimal costs at the individual-level. The ICER was most favorable ($232.70 per QALY gain) for administering an initial dose at 4 months of age due to fewer incremental program costs when shifting measles administration to an immunization visit already established under the Chinese vaccination program., Conclusion: We found potential beneficial health gains at a minimum cost associated with adding an earlier measles dose <8 months of age in China. Further investigation about disease transmission dynamics is required to more fully assess the tradeoffs of administering measles at a younger age to infants in China., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020. Published by Elsevier Ltd.)

Despite increasing global measles vaccination coverage, progress toward measles elimination has slowed in recent years. In China, children receive a measles-containing vaccine (MCV) at 8 months, 18-24 months, and some urban areas offer a third dose at age 4-6 years. However, substantial measles cases in Tianjin, China, occur among individuals who have received multiple MCV doses. This study describes the vaccination history of measles cases 8 months - 19 years old. Data came from measles cases in Tianjin's reportable disease surveillance system (2009-2013), and from a case control study (2011-2015). Twenty-nine percent of those in the surveillance dataset and 54.4% of those in the case series received at least one dose of MCV. The minimum and median time-to-diagnosis since vaccination revealed an increase in time since vaccination for incremental doses. Considerable measles cases in Tianjin occur in vaccinated children, and further research is needed to understand the reasons for vaccine failure., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: Use of dried blood spots (DBS) offers advantages over serum samples in studies conducted in resource-poor settings. The aim of this study was to compare the number of adequate spots collected across different demographic groups., Methods: Five DBS were collected from 3316 individuals aged 0-49 years in Tianjin, China for a measles antibody study; DBS were rated "adequate" or "inadequate." Linear regression, with the number of adequate DBS on a card as the outcome variable, was used to test for predictors of DBS adequacy., Results: There were 0 adequate DBS for 23% of participants and 5 adequate DBS for 24%. Mean number of adequate DBS was 1.68 in infants (<12 months), 2.57 (1-9 years), 3.49 (10-29 years), 3.08 (30-49 years). The number of adequate DBS increased over the study; the mean number of adequate DBS for the five years 2011-2015 were 1.21, 2.52, 3.40, 2.22, and 3.62, respectively. DBS quality was not related to measles IgG antibodies., Conclusions: DBS are an alternative for adults and children but pose challenges in infants, and improve with experience. In a resource-limited environment or in a scenario where more invasive techniques like venipuncture may be less accepted by the study population, DBS can be the preferred technique to efficiently obtain serum specimens for analyte testing., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Many measles cases in Tianjin, China, occur in infants whose mothers were born after widespread vaccination programs. We assessed age-specific decreases in maternal measles antibodies in infants and examined maternal and infant characteristics in relation to infant antibody titers., Methods: Infant and mother dyads were enrolled from a sample of immunization clinics in all Tianjin districts. Participants' antibody titers were measured from dried blood spots. A multivariable log-linear model regressed infant antibody titers onto infant and mother characteristics., Results: Among 551 infants aged ≤8 months, protective levels of measles antibodies were observed in infants whose mothers had measles titers ≥800 IU/mL (mean antibody titer, 542.5 IU/mL) or 400 to <800 IU/mL (mean, 202.2 IU/mL). Compared with infants whose mothers had no history of disease or vaccination, those with a history of disease had 1.60 times higher titers (95% confidence interval, 1.06-2.43)., Conclusions: Limited vaccination programs in the 1980s have resulted in many Chinese women with inadequate protection against measles and an accordingly low efficiency of transplacental transmission to a fetus. Current vaccination programs, which target children aged 8 months through adolescence may be ineffective in controlling transmission of measles to infants., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Control groups in previous case-control studies of vaccine-preventable diseases have included people immune to disease. This study examines risk factors for measles acquisition among adults 20 to 49 years of age in Tianjin, China, and compares findings using measles IgG antibody-negative controls to all controls, both IgG-negative and IgG-positive., Methods: Measles cases were sampled from a disease registry, and controls were enrolled from community registries in Tianjin, China, 2011-2015. Through a best subsets selection procedure, we compared which variables were selected at different model sizes when using IgG-negative controls or all controls. We entered risk factors for measles in two separate logistic regression models: one with measles IgG-negative controls and the other with all controls., Results: The study included 384 measles cases and 1,596 community controls (194 IgG-negative). Visiting a hospital was an important risk factor. For specialty hospitals, the odds ratio (OR) was 4.53 (95% confidence interval (CI): 1.28, 16.03) using IgG-negative controls, and OR = 5.27 (95% CI: 2.73, 10.18) using all controls. Variables, such as age or length of time in Tianjin, were differentially selected depending on the control group. Individuals living in Tianjin ≤3 years had 2.87 (95% CI: 1.46, 5.66) times greater odds of measles case status compared to all controls, but this relationship was not apparent for IgG-negative controls., Conclusions: We recommend that case-control studies examining risk factors for infectious diseases, particularly in the context of transmission dynamics, consider antibody-negative controls as the gold standard.

Background: In China, the measles vaccine is offered for free whereas the pneumococcal vaccine is a for-fee vaccine. This difference has the potential to influence how caregivers evaluate whether a vaccine is important or necessary for their child, but it is unclear if models of health behavior, such as the Health Belief Model, reveal the same associations for different diseases. This study compares caregiver perceptions of different diseases (measles, pneumonia and meningitis); and characterizes associations between Health Belief Model constructs and both pneumococcal vaccine uptake and perceived vaccine necessity for pneumonia, measles, and meningitis., Methods: Caregivers of infants and young children between 8 months and 7 years of age from Shanghai (n = 619) completed a written survey on their perceptions of measles, pneumonia, and meningitis. We used logistic regression models to assess predictors of pneumococcal vaccine uptake and vaccine necessity., Results: Only 25.2% of children had received a pneumococcal vaccine, although most caregivers believed that pneumonia (80.8%) and meningitis (92.4%), as well as measles (93.2%), vaccines were serious enough to warrant a vaccine. Perceived safety was strongly associated with both pneumococcal vaccine uptake and perceived vaccine necessity, and non-locals had 1.70 times higher odds of pneumonia vaccine necessity than non-locals (95% CI: 1.01, 2.88)., Conclusions: Most factors had a similar relationship with vaccine necessity, regardless of disease, indicating a common mechanism for how Chinese caregivers decided which vaccines are necessary. Because more caregivers believed meningitis needed a vaccine than pneumonia, health care workers should emphasize pneumococcal vaccination's ability to protect against meningitis.

Background: Measles is a highly infectious illness requiring herd immunity of 95% to interrupt transmission. Measles is targeted for elimination in China, which has not reached elimination goals despite high vaccination coverage. We developed a population profile of measles immunity among residents aged 0-49 years in Tianjin, China., Methods: Participants were either from community population registers or community immunization records. Measles IgG antibody status was assessed using dried blood spots. We examined the association between measles IgG antibody status and independent variables including urbanicity, sex, vaccination, measles history, and age., Results: 2818 people were enrolled. The proportion measles IgG negative increased from 50.7% for infants aged 1 month to 98.3% for those aged 7 months. After 8 months, the age of vaccination eligibility, the proportion of infants and children measles IgG negative decreased. Overall, 7.8% of participants 9 months of age or older lacked measles immunity including over 10% of those 20-39 years. Age and vaccination status were significantly associated with measles IgG status in the multivariable model. The odds of positive IgG status were 0.337 times as high for unvaccinated compared to vaccinated (95% CI: 0.217, 0.524)., Conclusions: The proportion of persons in Tianjin, China immune to measles was lower than herd immunity threshold with less than 90% of people aged 20-39 years demonstrating protection. Immunization programs in Tianjin have been successful in vaccinating younger age groups although high immunization coverage in infants and children alone would not provide protective herd immunity, given the large proportion of non-immune adults., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: China has repeatedly used supplemental immunization activities (SIAs) to work towards measles elimination, but it is unknown if the SIAs are reaching non-locals - migrants from rural to urban areas. This study characterized temporal trends in measles incidence by local and non-local residency and evaluated the impact of SIAs on measles incidence in Tianjin, China., Methods: Daily measles case-counts were tabulated separately by residency. These two datasets were combined so that each day had two observations. Poisson regression was conducted using generalized estimating equations with an exchangeable working correlation structure to estimate rate ratios (RRs)., Results: There were 12465 measles cases in Tianjin over the 10-year period. The rate of measles was higher in non-locals than locals before the 2008 SIA (RR 3.60, 95% confidence interval (CI) 3.27-3.96), but this attenuated to a RR of 1.22 between the 2008 and 2010 SIAs (95% CI 1.02-1.45). Following the 2010 SIA, non-locals had a lower rate of measles (RR 0.78, 95% CI 0.69-0.87)., Conclusions: The disparity in measles incidence between locals and non-locals was reduced following two SIAs. Sustained public health interventions will be needed to maintain low measles incidence among non-locals given the ongoing migration of people throughout China., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Measles incidence in China has declined over the last decade and elimination is targeted by 2020. Despite increases in routine immunization services and supplementary immunization activities (SIAs), periodic outbreaks continue to occur. In this paper, we examine measles epidemiology during 2005-2014 in Tianjin, China., Methods: Measles case data were extracted from a web-based communicable disease surveillance system. We examined the socio-demographic characteristics of measles case patients, including age, sex, urbanicity, residency status, and vaccination history. Demographic characteristics of cases were compared with the general population., Results: From January 1, 2005 to December 31, 2014, 12,466 measles cases in Tianjin were reported. Among the cases, 7179 (57.6%) were male and 5287 (42.4%) were female. Over time, more cases occurred in adults, and for the 2711 cases in 2014, the majority were either infants <1 year (558, 20.58%) or adults ≥ 20 years (2043, 75.36%). Municipal-wide SIAs in Tianjin occurred in 2008 and 2010 with reduction in measles cases the following year for both (189 cases in 2009, and 37 cases in 2011). The number of cases rebounded to pre-SIA levels or higher within 1-3 years following each SIA: 1990 cases in 2010 and 2711 cases in 2014. Vaccination status was reported as "none" or "unknown" for 84% of all reported measles cases., Conclusions: Despite the general decline in cases, measles outbreaks continue to occur. Although the SIAs reduce numbers in their immediate aftermath, case counts rebound 1-3 years after the intervention. Continued monitoring of cases through disease surveillance activities accompanied by targeted immunization activities, including to adults, can help ensure progress toward elimination., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Measles is a highly infectious disease, and timely administration of two doses of vaccine can ensure adequate protection against measles for all ages in a population. This study aims to estimate the proportion of children aged 8 months to 6 years vaccinated on time with measles-containing vaccines (MCV) and vaccinated during the 2008 and 2010 measles supplementary immunization activities. This study also characterizes differences in mean age at vaccination and vaccination timeliness by demographic characteristics, and describes maternal knowledge of measles vaccination., Methods: Immunization records were selected from a convenience sample of immunization clinics in Tianjin, China. From the records, overall vaccination coverage and timely vaccination coverage were calculated for different demographic groups. Mothers were also interviewed at these clinics to ascertain their knowledge of measles vaccination., Results: Within the 329 immunization clinic records, child's birth year and district of residence were found to be significant predictors of different measures of vaccine timeliness. Children born in 2009 had a lower age at MCV dose 2 administration (17.96 months) than children born in 2005 (22.00 months). Children living in Hebei, a district in the urban center of Tianjin were less likely to be vaccinated late than children living in districts further from the urban core of Tianjin. From the 31 interviews with mothers, most women believed that timely vaccination was very important and more than one dose was very necessary; most did not know whether their child needed another dose., Conclusions: When reviewing MCV coverage in China, most studies do not consider timeliness. However, this study shows that overall vaccination coverage can greatly overestimate vaccination coverage within certain segments of the population, such as young infants.

Background: We characterize the risk factors for delayed polio dose 1, diphtheria-tetanus-pertussis (DTP) dose 1, pentavalent dose 1, and measles dose 1 in Ethiopian infants. We also examine the interaction between institutional delivery and demographic factors on the birth doses of the BCG and polio vaccines to better understand factors influencing vaccination. Methods: Using the 2011 Ethiopia Demographic and Health Survey, we calculated the distribution of the study population across different demographic and vaccination characteristics. We computed acceleration factors using a multivariable accelerated failure time model with a Weibull distribution to account for left and right censoring. For the birth doses, we further specified an interaction term between institutional delivery and every other a priori specified independent variable to test whether institutional delivery modifies sociodemographic disparities in vaccination timeliness. Results: Low wealth status, home delivery, and ethnicity are risk factors for delayed vaccination of polio 1, DPT 1, pentavalent 1, and measles 1. Religion is a risk factor for measles 1 vaccination delay and rural residence are risk factors for delayed DPT1 and polio 1 doses. For birth doses of polio and BCG, institutional delivery attenuated many sociodemographic disparities in vaccination delay, except for urbanicity, which showed rural dwellers with more delay than urban dwellers with an institutional vs home birth. Conclusions: Less delayed vaccination among children with institutional deliveries highlights the importance of perinatal care and the potential for promoting healthy behaviors to parents. Persistent disparities between urban and rural residents, even among those with institutional births, can be targeted for future interventions. Timely vaccination is key to prevention of unnecessary childhood mortality. [ABSTRACT FROM AUTHOR]