Jul 2026· The Indian journal of medical research· Vol 164, pp. 311 - 315· 0 citations· 17 references
Medicine
TL;DR
This study provides the first evidence of suboptimal measles antibody response among children from a tribal area of Odisha, India, despite high vaccination coverage.
Abstract
Background and objectives Globally, measles cases remain above 10 million despite the introduction of two dose measles vaccination schedule since 2000. India reported 13220 cases during 2023-2024, ranking fourth globally. This raises concern regarding the effectiveness of the ongoing programme to achieve measles elimination. Tribal dominated regions in countries such as India needs particular attention due to their higher burden of childhood morbidity and mortality. This study aimed to estimate the proportion of children developing protective antibody levels following two doses of measles vaccine in a tribal location and to identify potential risk factors associated with non-response. Methods A tribal dominated region, the undivided Phulbani district of Odisha, India, was randomly selected. Using cluster sampling, 1375 Infants aged 8 months were enrolled from 30 tribal habitations and followed to document vaccination status. Blood samples (n=1185) were collected three months after the second measles vaccine dose, and their measles IgG antibody levels were quantified. Variables likely to influence antibody response were recorded and statistically evaluated. Results Two-dose measles vaccine coverage was 99.6%; however, 55.1% (n=653) of children demonstrated seropositivity (IgG titre ≥ 250 IU/L). Male gender was significantly associated with suboptimal antibody response. Age, nutritional status, interval between first and second vaccine doses, and vaccination logistics were not found to influence antibody response. Interpretation and conclusion This study provides the first evidence of suboptimal measles antibody response among children from a tribal area of Odisha, India, despite high vaccination coverage. There is a need to understand the immune persistence among such a vulnerable population, where measles control remains a challenge.
Despite sustained high measles-containing vaccine (MCV) coverage, maintaining population immunity after measles elimination remains challenging. This study aimed to characterize measles antibody persistence, identify immunity gaps, and evaluate factors associated with seronegativity in China.
A multicenter cross-sectional serological survey was conducted among 2,083 participants from Jiangsu Province and Xinjiang Uygur Autonomous Region during 2024–2025. Measles-specific IgG antibodies were measured using ELISA, with seropositivity defined as IgG ≥200 mIU/mL. Restricted cubic spline models were used to assess antibody kinetics after excluding individuals without documented vaccination, those sampled within one month after vaccination, and potential primary vaccine failures. Multivariable logistic regression and propensity score matching were performed to evaluate factors associated with seronegativity.
Overall measles IgG seropositivity was 84.59% (95% CI: 82.98–86.08%), with a GMT of 482.48 mIU/mL. Seropositivity varied significantly by region, ethnicity, age, and vaccination history. Antibody levels showed a non-linear decline with increasing time since vaccination, and each additional year since the last vaccination increased seronegativity risk (AOR = 1.11, 95% CI: 1.07–1.15). Children aged 8–17 months had the lowest seropositivity (28.13%), indicating a potential susceptibility window. Although migrants had higher seropositivity than permanent residents (93.04% vs. 83.90%), migration status was not independently associated with seronegativity after adjustment.
High MCV coverage does not necessarily ensure sustained population immunity in the post-elimination era. Waning humoral immunity, delayed vaccination, and heterogeneous vaccination histories contribute to residual susceptibility, highlighting the need for immunity-based surveillance and targeted interventions.
Wen Wang, Zhisheng Chen, Hanwen Zhang et al.· Frontiers in Immunology· 0 citations
Background: Measles is a contagious disease with high morbidity and mortality rates. Globally, measles immunization coverage has reached 81% for the first dose and 71% for the second dose. In Southeast Asia, the coverage is 91% for the first dose and 85% for the second dose; however, these figures remain below the measles elimination target. Purpose: identify the factors influencing second-dose measles immunization coverage. Methods: The method used is a Systematic Literature Review with keywords formulated based on the PICO framework: Population: “children,” Exposure: “second-dose measles vaccine,” and Outcome: “associated factors,” “predictors,” or “determinants.” From a total of 1,159 articles identified, ten studies met the inclusion criteria and were analyzed further. Results: The results show that second-dose measles immunization coverage is influenced by several factors, including maternal age, education level, knowledge, utilization of maternal health services, and accessibility to healthcare facilities. Maternal health service utilization, such as antenatal care visits, delivery at health facilities, and postnatal checkups, significantly increases the likelihood of children receiving the second dose. Conversely, barriers such as long distances, limited transportation, and long waiting times remain major challenges. Conclusion: Therefore, strengthening education, integrating maternal health services with immunization programs, and expanding access in remote areas are essential to improving measles immunization coverage. These efforts provide an important foundation for formulating more effective policies to support both global and national measles elimination strategies.
Anita Dewi Anggraini, Diyas Windarena Anggraini, Dwi Ardani Rochmaniah Anggraini et al.· Nurse and Health: Jurnal Kep...· 0 citations
The study revealed a national post-campaign vaccination coverage of 75.3% in 2024, a notable 10-point increase from 65.3% in 2022, however, significant geographical disparities persisted, with lower coverage in large cities compared to landlocked and intermediate districts.
F. Alain, Faly Hariniaina Randrianasolo, M. Razafimahatratra et al.· PLOS Global Public Health· 0 citations
Malaria remains a leading cause of child mortality in sub-Saharan Africa. Cameroon introduced the RTS,S/AS01 malaria vaccine in 2024, but real-world evidence on its early effects, coverage, and safety remains limited. This study evaluated these parameters among children under 36 months in the high-transmission Soa Health District. A community-based analytical cross-sectional study was conducted from February to May 2025. Households were selected by stratified cluster sampling (62 clusters, 622 participants). Children aged < 36 months who had resided in the district for ≥ 3 months were eligible. Vaccination status and malaria episodes (confirmed by rapid diagnostic test or microscopy) during the preceding six months were abstracted from cards. Primary exposure was ≥ 2 doses of RTS,S/AS01; primary outcome was documented malaria episodes. Multivariable modified Poisson regression with robust standard errors was used to estimate risk ratios (RR) adjusted for age, breastfeeding, insecticide-treated net (ITN) use, and intermittent preventive treatment in infancy (IPTi). The effect of the vaccine was measured as (1–adjusted RR) × 100. Coverage and adverse events were also assessed. Among 622 children (mean age 17.9 months, 51.4% female), documented coverage of dose 1 was 56·8% (95% CI 53.5–61.7), dropping to 46·6% for dose 2 and 39·0% for dose 3. Perceived free access (aRR 1.97, 95% CI 1.47–2.64) and knowledge of a nearby vaccination facility (aRR 1.86, 95% CI 1.41–2.45) were strongly associated with uptake. In the cross-sectional analysis, children who received ≥ 2 doses were associated with a 50% lower occurrence of malaria episodes (aRR 0.50, 95% CI 0.34–0.73, p = 0.001) compared with those receiving ≤ 1 dose. Minor adverse events occurred in 27% (fever 93%, injection site swelling 10%). In this high-burden Cameroonian setting, two or more doses of RTS,S/AS01 were associated with a lower occurrence of malaria episodes favourable safety profile. Coverage remains suboptimal, and dropout is high. Ensuring free access and strengthening community awareness are critical for maximising vaccine uptake.
C. Bekolo, Gladys Aimée Simo Zekeng, Paul Onambele et al.· Tropical Medicine and Health· 0 citations
Multiple socioeconomic, structural and operational factors were associated with unvaccinated rates, highlighting the relevance of healthcare service organization even in favorable social contexts and classifying municipalities into risk profiles may help guide interventions to improve coverage.
I. N. Schrarstzhaupt, F. A. Diaz-Quijano, F. Fontana Sutile Tardetti Fantinato et al.· medRxiv· 0 citations
OBJECTIVE
This study estimates Australia's measles susceptibility across all age groups. To our knowledge, this study is the first internationally to combine multiple consecutive serosurvey and population immunisation register data.
METHODS
We estimated age-specific measles susceptibility in 2019 using data from nationally representative seroprevalence surveys for people born between 1920 and 1960 (infection-acquired immunity) and those born 1961-1999 (infection/vaccine-acquired immunity). For people born 2000-2018 (vaccine-acquired immunity only), we estimated measles susceptibility from coverage of one or two doses of measles-containing vaccine from the Australian Immunisation Register and presumed vaccine effectiveness, adjusting for 0·04% waning of protection per year.
RESULTS
Susceptibility increased from less than 1% across those born 1920-1960 to 11% for the 1993-1995 cohort, and ranged from 7-14% for those born 2000-2015. We estimated that 1.7 million Australians (6·7%) were susceptible to measles in 2019 (95%UI: 1·3-3·2 million). Among notifications of measles infection between 2008 and 2022, people aged 15-35 years at time of notification accounted for 50%.
CONCLUSIONS
Despite sustained high two-dose measles vaccine coverage, Australia's overall population-level measles immunity is at the lower end of the World Health Organization estimated herd protection threshold range (93-95%).
IMPLICATIONS FOR PUBLIC HEALTH
Our estimates provide baseline data to inform vaccination activities to address immunity gaps in older age groups, particularly those likely to travel internationally.
Zoë Croker, A. McLure, Stephen B Lambert et al.· Australian and New Zealand J...· 1 citation
