Epidemic management in a measles outbreak in 2023,the return of vaccine-preventable diseases:A single center,retrospective observational study

Objective:To investigate the importance of immunization in preventing measles infection and to determine the most useful laboratory tests for confirmation of measles.Methods:This study included pediatric cases evaluated with a presumed diagnosis of measles between December 2022 and June 2023,at Marmara University Pendik Training and Research Hospital.The effects of vaccination status and underlying disease on the clinical course,treatments,and complications were evaluated.Results:In total,117 patients were enrolled in the study with a median age of 80 months(IQR:32.5-125.0).Twelve patients with contact history were asymptomatic and had an underlying disorder,and intravenous immunoglobulin was given to them for post-exposure prophylaxis.Fifty-one patients had confirmed measles diagnosis.Ribavirin treatment was given to three patients(a newborn,a girl with rhabdomyosarcoma,and a healthy boy)with respiratory distress.Seventy-eight percent of confirmed measles cases were unvaccinated,and all hospitalized cases were unvaccinated or under-vaccinated.Four full-vaccinated children had confirmed measles infection.Measles PCR from nasopharyngeal swabs was negative in all of them,and their diagnosis was established with anti-measles IgM positivity.Conclusions:The measles vaccine is the most effective way to protect from measles and measles-related complications.Although measles can also occur in fully vaccinated patients,the disease is milder than in unvaccinated patients.Using ELISA and RT-PCR tests together may be beneficial in patients with high clinical suspicion for early diagnosis.

Novel Investigation of Stochastic Fractional Differential Equations Measles Model via the White Noise and Global Derivative Operator Depending on Mittag-Leffler Kernel

Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this paper,we constructed a stochastic fractional framework of measles spreading mechanisms with dual medication immunization considering the exponential decay and Mittag-Leffler kernels.In this approach,the overall population was separated into five cohorts.Furthermore,the descriptive behavior of the system was investigated,including prerequisites for the positivity of solutions,invariant domain of the solution,presence and stability of equilibrium points,and sensitivity analysis.We included a stochastic element in every cohort and employed linear growth and Lipschitz criteria to show the existence and uniqueness of solutions.Several numerical simulations for various fractional orders and randomization intensities are illustrated.

Resurgence of measles virus infection in an eliminated country, Sri Lanka

Objective:To describe the situation of measles in Sri Lanka from May to November,2023 and to define the role of virology laboratory towards case confirmation and epidemiological and genetic characterization of the outbreak.Methods:This retrospective study analyzed all samples tested for measles from 1st of May to 30th of November,2023 at National Measles Rubella Laboratory,Sri Lanka.According to the World Health Organization(WHO)algorithm,serum and oropharyngeal/nasopharyngeal swabs were tested with WHO recommended kits for anti-measles IgM and measles virus specific RNA,respectively.Selected RNA positive samples were sequenced at reference laboratory,India.Analysis of sequencing data and construction of phylogenetic tree were carried out at National Measles Rubella Laboratory.Data was analyzed using descriptive statistics.Results:Of the total 1132 serum samples and 497 oropharyngeal/nasopharyngeal swabs from 1326 patients,657(49.5%)patients were confirmed as measles by anti-measles IgM,measles virus specific RNA or both.Males(55.6%,n=365)and the age group from>20 to≤30 years(33.0%,n=217)predominated positive patients.All provinces reported measles positive cases.All samples sequenced(100%,n=42)were genotype D8 with 95.2%(n=40)bearing Victoria.Australia origin.Conclusions:We described resurgence of measles in an eliminated country,confirming the genotype to be D8,one of the two genotypes currently circulating globally.Further,the study strongly convinced the importance of a strengthened virological surveillance system in an eliminated country,despite its eliminated status.

A rare complication of measles infection presented with subacute sclerosing panencephalitis: Report of two cases in India

Rationale:Subacute sclerosing panencephalitis(SSPE)is a progressive neurological disorder caused by persistent measles virus infection.SSPE predominantly affects children and adolescents.The symptoms usually develop 6-15 years after measles infection and ultimately leading to death in many cases.Patient concerns:Patient 1 presented with cognitive decline and myoclonus and the Patient 2 presented with diminution of vision with myoclonic jerks.Diagnosis:Based on the clinical features with a characteristic electroencephalogram pattern and the presence of a high titer of anti-measles IgG in serum and cerebrospinal fluid,these patients were diagnosed as SSPE.Interventions:Antiepileptics were started for controlling myoclonus along with supportive treatment.Outcomes:Both patients were discharged on antiepileptics and supportive care.Lessons:Whenever there are unusual clinical manifestations with unknown vaccination status,SSPE can be suspected and the cerebrospinal fluid should be examined for anti-measles antibodies.Our case study also highlights the importance of universal coverage of measles vaccination.To reduce the incidence of measles and associated deaths,it is important to maintain a high level of immunization coverage for the measles vaccine and to strengthen all the integral components of the national immunization program.

Epidemiological, Clinical Aspects and Outcome of Measles in a Low-Income Country in 2023

Introduction: Measles remains a worrying health problem in sub-Saharan African countries. There have been measles outbreaks in Cameroon with the most recent occurring between October 2022 and September 2023. The Centre region of Cameroon was the most affected in the country and being at the frontline of the fight against this illness, we conducted this study in order to determine the epidemiological and clinical characteristics as well as the outcome of children who contracted the measles and were hospitalized at the Yaoundé Gynaeco-Obstetric and Pediatric Hospital. Methodology: We conducted a cross-sectional descriptive and prospective study for one year from October 2022 to November 2023 corresponding to the duration of the outbreak. We included all children admitted in the pediatric unit for measles and its complications during this period. Results: In total, 60 children were enrolled. Their caregivers were mostly their mothers who had a mean age of 34.71 ± 9.55 years living in significant precarious conditions for the majority. The median age of children was 16 months (09 - 30 months). Twenty six percent of children (16) were less than 9 months. Girls were predominant (55%). Most children were not up to date with their routine EPI vaccination (80%) and most did not receive the measles and Rubella vaccine (76.67%). Clinical manifestations, included fever, conjunctivitis, and cough. Skin rash and catarrh (98.33% and 86.67% respectively) are the case definition signs of measles. The outcome was unfavorable for 4 children. One had a neurological disorder: coma and three presented with pneumonia and severe respiratory distress (6.67%). Conclusion: Measles is still being a reality and claiming lives in our context, emphasis should be made on immunization coverage and if possible, advocacies should be formulated to decrease the age of measles vaccine administration.

Vaccination and Measles Epidemic in the Republic of Congo

Measles is a highly infectious, vaccine-preventable viral disease. Often forgotten, it is potentially fatal. Its main symptoms are: fever, cough, conjunctivitis, rhinitis and skin rash. Serological diagnoses by ELISA test based on the detection of anti-measles virus immunoglobulins M and G (IgM and IgG), are used respectively for the confirmation of suspected cases notified by means of clinical signs of the disease in health structures of the twelve departments of the Republic of Congo involved in the epidemiological surveillance of the disease, and for the evaluation of the immunity conferred by vaccination. During 2021, 459 suspected cases of measles were reported and sampled throughout the country, despite the administration under the Expanded Routine Immunization Program (EPI), of 2 doses of the combined measles-rubella vaccine (RR1 and RR2) in 2020. The notification rate was higher in the south of the country, more precisely in the health structures of the departments of Pointe-Noire (42%) and Brazzaville (11%). During the year 2021, 459 suspected cases of measles were notified and sampled throughout the country with a high notification rate in the south of the country, more precisely in the health structures of the Pointe-Noire departments (42%) and Brazzaville (11%). The samples consisting of human blood (serum) were sent to the National Public Health Laboratory and analyzed by various ELISA tests for the detection of anti-measles immunog-lobulins M and G. The analysis of the results obtained shows that the measles virus circulated in all departments of the country. 154 cases (33.55%) were confirmed positive by IgM ELISA and 98 positive cases (63.63%) were patients vaccinated against measles. Vaccination coverage in RR1 of [50%-95% [(first dose) as well as the lowest RR2 < 50% (second dose) undoubtedly because the COVID-19 pandemic could be the cause of the high frequency of cases positive vaccinated. The non-detection of IgG immunoglobulins in vaccinated patients observed by IgG ELISA tests revealed that 63.26% of vaccinated patients were not immunized against the measles virus. These results confirm those obtained during the Elisa IgM analysis and make it possible to deduce that the quality, the number of doses not properly administered, the individual characteristics of the people as well as the poor conservation of the administered vaccine (non-compliance with the cold chain) would explain the high proportion of positive cases of vaccinated measles observed.

Knowledge and associated factors of healthcare workers on measles vaccine and cold chain management at health institutions in Gondar,Ethiopia

Objective:To assess the knowledge of healthcare workers on the measles vaccine and its cold chain management.Method:An institutional-based cross-sectional study was conducted from February 1 to March 30,2022 in Gondar City Administration public health institutions among 165 healthcare workers.Data were collected using a structured questionnaire.In addition,an on-spot observation checklist was used to assess the availability,status and management of the cold chain.A logistic regression model was used to assess the relationship between the outcome and predictor variables.Crude and adjusted odds ratios were calculated with 95%confidence intervals.Results:Overall,87(52.7%;95%CI 44.8%-60.5%)of the healthcare workers had unsatisfactory knowledge regarding the measles vaccine and its cold chain management.One hundred thirty-six(82.4%)healthcare workers correctly mentioned the recommended range of temperature(2-8℃)for measles vaccine storage.Healthcare workers aged 18-29 years(P=0.001)and 30-44 years(P=0.014)were observed as determinants of unsatisfactory knowledge on the measles vaccine and its cold chain management.One hundred and five(63.6%)of the healthcare workers did not correctly mention the type of measles vaccine used in routine immunization.More than one-third(36.4%)of the healthcare workers perceived that the measles vaccine is not safe and could cause measles.Conclusions:More than half of the healthcare workers in the study area had unsatisfactory knowledge on the measles vaccine and its cold chain management.It is necessary to provide technical support and in-service training for healthcare workers to ensure optimal immunization effectiveness.

Factors Contributing to the Acceptability of Second Dose of Measles Vaccine among Children in Livingstone District, Zambia

Introduction: Measles is a viral disease that is a major public health problem in both developed and developing countries. It is a contagious disease resulting from infection with the measles virus and is still responsible for more than 100,000 deaths per year. Although vaccination is one of the most successful and cost-effective public health interventions to reduce mortality and morbidity, approximately 1.4 million children worldwide die from vaccine-preventable diseases each year. In Zambia, MCV2 was 66% below WHO recommended target of 95%. This study therefore assessed the acceptability of second dose measles vaccination services among caretakers/mothers with children less than two years of age in Livingstone, Zambia. Methods: The study used analytical cross-sectional study design. A logistic regression analysis was performed to identify factors associated with acceptability of the second dose of measles vaccine. A semi structured questionnaire was administered to collect data on socio demographic characteristics and factors related to acceptability of the second dose of measles vaccine. SPSS version 26.0 was used for descriptive and inferential analysis at 5% level of significance. Results: There was no statistically significant difference in acceptability of the second dose of measles vaccine by gender, marital status, type of employment, income level, socio-cultural and traditional beliefs, and education level. However, there was a statistically significant difference in acceptability of the second dose of measles vaccine by knowledge level of second dose of measles vaccine. A Chi square test result indicated that second dose acceptability was higher with less children than that of respondents with many children (χ2(5) = 15.3, p and knowledge levels (χ2(2) = 14.8, p Changes in knowledge level from medium to high reduced the odds of second dose measles vaccine acceptability. Furthermore, this study showed that acceptance of the second measles vaccination increased from mothers/caretakers with low knowledge (3.6%) to medium knowledge (13.3%) and finally high knowledge (83.1%). Conclusion: Tailored messaging to increase knowledge among mothers and caregivers on the importance of the second dose of measles vaccine is critical in improving acceptability. Therefore, the researchers recommend that the health providers should continue to raise awareness associated with the low acceptability of the second dose of measles vaccine and improve on child preventable diseases such as measles.

Maculopapular Rash with Fever: Reporting of a Case with Imported Measles and Diagnostic Difficulties in Non-Epidemic Times

Background: Measles is a highly contagious infection caused by the measles virus with a worldwide distribution. Measles is one of the diseases that have been reported in our country since 1945. It is known that international travelers are an important source of infectious pathologies. Our goal is to document a case of imported Measles and the difficulty of diagnosing it, especially in non-epidemic times. Cases Presentation: We presently report a 20-year-old woman who was hospitalized at the Infectious Disease Service for fever and maculopapular rash. She had traveled outside of Albania. Measles ELISA IgM (blood) resulted positive while other serological examinations resulted negative. Our case was treated with antibiotics, multivitamins and intravenous fluids. She was subsequently discharged home in good clinical condition. Conclusions: Measles should be included in the differential diagnosis of patients with symptoms of fever and rash, in particular when they have traveled abroad. Patients who have received the Measles vaccine should not be excluded from clinical suspicion and further diagnostic tests for this disease as it can affect this group of patients as well.

Respiratory Complications of Measles in the Pediatric Ward of the Regional Hospital of Kindia/Guinea

Introduction: Measles is a highly contagious infectious disease caused by the measles virus belonging to the morbillivirus genus, the measles morbillivirus species and the Paramyxoviridae families. The aim was to study respiratory complications due to measles in children aged 1 to 15 in the pediatric ward of the Kindia regional hospital. Materials and Methods: A transversal descriptive study was carried out in the pediatrics department of the Kindia Regional Hospital from October 1, 2019, to March 31, 2020, on children aged 1 to 15 years hospitalized for measles with respiratory complications. Results: 53 cases of measles were recorded, i.e. 11.71% of hospital pathologies including 32 cases of respiratory complications, i.e. 60.38% with an M/F sex ratio of 1.66, male predominance of 62.5%, and a mean age of 4.10 ± 2.8 years. The outcome was favorable in 90.62% of our patients. The mortality was 9.38% with an average hospital stay of 6.8 ± 3.04 days. Conclusion: The respiratory complication of measles is a serious pathology due to the risk of mortality that it can cause, a consultation followed by rapid treatment can contribute to a reduction in complications and a faster cure.

Contributions of the Measles Follow-Up Vaccination Campaign to Improving the Vaccination Coverage of Children Aged 6 - 59 Months in the Democratic Republic of the Congo in 2019

Background: In accordance with its measles elimination strategic plan 2012-2020, the Democratic Republic of the Congo (DRC) organized a follow-up vaccination campaign against measles from October to December 2019 in 26 provinces. This study aims to establish the contribution of this supplementary vaccination campaign to protecting children against measles. Methods: The survey was carried out in November 2020 among households of the DRC, according to the 2018 revised version of the World Health Organization’s stratified cluster sampling method, using multiple stage sampling. It targeted 280 children aged 6 - 59 months per stratum or province, with 10 children in each of the 28 selected clusters. Data collection using tablets with centralized and real-time data processing was preceded by enumeration to refine the household sampling frame. Clusters and households were selected by random draw. Data collected with CS Pro 7 software were analyzed with SPSS, Epi info 7 and Excel software to determine indicators and make before-after comparisons using the McNemar test, at a precision threshold of 5%. Results: Of the 8535 surveyed children, 89.5% were vaccinatedduring the follow-up campaign and 81.6% were vaccinated before. Only 3.7% had correctly completed campaign vaccination cards. Estimated vaccination coverage increased from 80.8% before the campaign to 92.6% after the campaign (p 0.001). Vaccination coverage after campaign against measles improved in all provinces (p < 0.001) except Bas-Uele and Maniema. Thirteen provinces reached the national coverage target of 95%, compared to five before the campaign. The proportion of zero-dose children dropped significantly after this campaign from 19.2% to 7.4% (p 0.001), and even fell below 1% in six provinces. Conclusion: This measles vaccination campaign improved overall vaccination coverage by 10% and reached more unvaccinated children. Efforts must continue to improve the retention of vaccination card, the adherence of unvaccinated children and the effectiveness of routine vaccination.

Measles Virus IgG Avidity Assay for Use in Identification of Measles Vaccine Failures in Tianjin, China

Objective To identify measles vaccine failures in Tianjin, China using a measles virus Ig G avidity assay.Methods The China Information System for Disease Control and Prevention(CISDCP) was used to collect information about measles cases and blood specimens in Tianjin from 2013 to 2015. Measlesspecific Ig M and Ig G antibodies were detected using Enzyme-Linked Immunosorbent Assay(ELISA).Avidity testing for measles Ig G was performed using a commercial enzyme immunoassay(EIA).Results A total of 284 confirmed measles cases were identified. Of this total, 262(92.25%) were in patients aged ≥ 20 years. High avidity was exhibited in 172(60.56%) cases, while 80(28.17%) cases demonstrated low avidity. High avidity was detected in only 21.43% of cases in patients aged < 1 year.The proportion of high avidity increased with age, and was significantly higher in patients aged 30–39 years at 70.07%(χ~2 = 17.27, P = 0.002). Of the 52 measles cases in patients with a history of vaccinations,41(78.85%) cases showed high avidity, indicating secondary vaccine failures(SVF). In these vaccinations,there was no significant difference(P > 0.05) in clinical severity between high avidity and low avidity cases. However, regardless of vaccination status, clinical severity was significantly lower in high avidity cases(P < 0.001) than in low avidity cases. The percentages of positive measles Ig M results in high avidity and low avidity cases were 66.28% and 91.25%, respectively. Geometric Mean Concentration(GMC) was significantly lower in high avidity cases at 33.73 U/m L, compared to 166.07 U/m L in low avidity cases.Conclusions Low clinical severity and inconclusive Ig M antibody results are more likely in high avidity measles cases. Measles cases were more common in adults. Therefore, a further dose of vaccines should be recommended for 30–39 years in Tianjin.

Viral co-infections among children with confirmed measles at hospitals in Hanoi,Vietnam,2014

Objective:To characterize viral co-infections among representative hospitalized measles cases during the 2014 Hanoi outbreak.Methods:Throat swabs were collected from 54 pediatric patients with confirmed measles,and molecular diagnostics performed for 10 additional viral respiratory pathogens(Influenza A/H1N1pdm09;A/H3N2 and influenza B;Parainfluenza 1,2,3;Respiratory Synctial Virus,RSV;human Metapneumovirus,hM PV;Adenovirus and Picornavirus).Results:Twenty-one cases(38.9%) showed evidence of infection with other respiratory viruses:15 samples contained measles plus one additional virus,and 6 samples contained measles plus 2 additional viruses.Adenovirus was detected as a predominant cause of co-infections(13 cases;24.1%),followed by RSV(6 cases;11.1%),A/H1N1pdm09(3 cases;5.6%),PIV3(3 cases;3.7%),Rhinovirus(3 cases;3.7%) and hM PV(1 case;1.96%).Conclusions:Viral co-infections identified from pediatric measles cases may have contributed to increased disease severity and high rate of fatal outcomes.Optimal treatment of measles cases may require control of multiple viral respiratory pathogens.

In situ tumor vaccination with adenovirus vectors encoding measles virus fusogenic membrane proteins and cytokines

AIM： To evaluate whether intratumoral expression of measles virus fusogenic membrane glycoproteins H and F （MV-FMG）, encoded by an adenovirus vector Ad.MV-HI F, alone or in combination with local coexpression of cytokines （IL-2, IL-12, IL-18, IL-21 or GM-CSF）, can serve as a platform for inducing tumor-specific immune responses in colon cancer.METHODS： We used confocal laser scanning microscopy and flow cytometry to analyze cell-cell fusion after expression of MV-FMG by dye colocalization. In a syngeneic bilateral subcutaneous MC38 and Colon26 colon cancer model in C57BL/6 and BALB/c mice, we assessed the effect on both the directly vector-treated tumor as well as the contralateral, not directly vector- treated tumor. We assessed the induction of a tumorspecific cytotoxic T lymphocyte （CTL） response with a lactate dehydrogenase （LDH） release assay.RESULTS： We demonstrated in vitro that transduction of MC38 and Colon26 cells with Ad.MV-H/F resulted in dye colocalization, indicative of cell-cell fusion, in addition, in the syngeneic bilateral tumor model we demonstrated a significant regression of the directly vector-inoculated tumor upon intratumoral expression of MV-FMG alone or in combination with the tested cytokines. We observed the highest anti-neoplastic efficacy with MV-FMG and lL-21 coexpression. The degree of tumor regression of the not directly vector-treated tumor correlated with the anti-neoplastic response of the directly vector-treated tumor. This regression was mediated by a tumor-specific CTL response.CONCLUSION： Our data indicate that intratumoral expression of measles virus fusogenic membrane glycoproteins is a promising tool both for direct tumor treatment as well as for tumor vaccination approaches that can be further enhanced by cytokine coexpression.

Gastrointestinal cytomegalovirus disease secondary to measles in an immunocompetent infant:A case report

BACKGROUND Gastrointestinal cytomegalovirus(CMV)disease occurs commonly in immunocompromised/immunodeficient patients with advanced human immunodeficiency virus infection,neoplasm,solid organ transplantation,hematopoietic stem cell transplantation,or treatment with immunosuppressants,but is rarely reported in association with measles infection.CASE SUMMARY We describe a case of extensive gastrointestinal CMV disease secondary to measles infection in a 9-mo-old boy who presented with persistent fever and bloody diarrhea.His condition was improved after ganciclovir treatment.Serological analysis of CMV showed negative immunoglobulin(Ig)M and positive IgG.Blood CMV-DNA was 9.26×103 copies/mL.The diagnosis of gastrointestinal CMV disease was confirmed by histopathological findings of intranuclear and intracytoplasmic inclusions and Owl’s eye inclusion.This case highlights the differential diagnosis and histopathological characteristics of gastrointestinal CMV infection and laboratory tests.CONCLUSION Extensive gastrointestinal CMV lesions can be induced by the immune suppression secondary to measles infection.Rational,fast,and effective laboratory examinations are essential for suspected patients.

Forecasting Measles Immunization Coverage Using ARIMA Model

This study aimed to find a model to forecast monthly measles immunization coverage using Autoregressive Integrated Moving Average (ARIMA). The monthly registered data for measles immunization coverage from January 2014 to December 2018 were used for the development of the model. The best model with the smallest Normalized Bayesian Information Criterion (BIC) of 8.673 is ARIMA (0, 1, 0). ARIMA (0, 1, 0) was used to forecast the monthly measles immunization coverage for the next 36 months from January 2018 to December 2020. The results obtained prove that this model can be used for forecasting future immunization coverage and will help decision-makers to establish strategies, priorities, and proper use of immunization resources.

A Stochastic SVIR Model for Measles

In this article, we consider the construction of a SVIR (Susceptible, Vaccinated, Infected, Recovered) stochastic compartmental model of measles. We prove that the deterministic solution is asymptotically the average of the stochastic solution in the case of small population size. The choice of this model takes into account the random fluctuations inherent to the epidemiological characteristics of rural populations of Niger, notably a high prevalence of measles in children under 5, coupled with a very low immunization coverage.

Approximations of Quasi-Stationary Distributions of the Stochastic <i>SVIR</i>Model for the Measles

In this paper, we analyze the quasi-stationary distribution of the stochastic SVIR (Susceptible, Vaccinated, Infected, Recovered) model for the measles. The quasi-stationary distributions, as discussed by Danoch and Seneta, have been used in biology to describe the steady state behaviour of population models which exhibit discernible stationarity before to become extinct. The stochastic SVIR model is a stochastic SIR (Susceptible, Infected, Recovered) model with vaccination and recruitment where the disease-free equilibrium is reached, regardless of the magnitude of the basic reproduction number. But the mean time until the absorption (the disease-free) can be very long. If we assume the effective reproduction number Rp < 1 or , the quasi-stationary distribution can be closely approximated by geometric distribution. β and δ stands respectively, for the disease transmission coefficient and the natural rate.

Small-scale outbreak of measles in the Irewole local government area of Osun State in Nigeria

Objective:An investigation of an outbreak of measles in a district in Nigeria was initiated following confirmation of the outbreak.The objectives of the study were to assess the size and determine the cause of the outbreak. Methods:Visits were made to health facilities and affected communities.Cases were line-listed using specified forms and descriptive epidemiology carried out on collected data.Results:A total of 18 cases and 0 deaths were identified over a period of six weeks.Two of the cases(11%) were 【 9 months of age.The proportion of zero-dose children was 39%.Conclusion:Low herd immunity was suggested as the cause of the outbreak.

Association between measles antibodies in vaccinated and naturally infected mothers with protective antibodies and the occurrence of measles in their children:A cross-sectional study in the Bavi district of Hanoi

Objective:To determine the concentration and rate of decay of maternal IgG antibodies against measles prevalence in infants of vaccinated or naturally infected mothers and study initial measles immunization occurs in nine-month-old children.Methods:In total,401 pregnant women and the same number of their subsequent newborns were recruited in the Bavi district of Hanoi in 2016-2017;they were divided into two groups:Older women(born before 1985,n=201)and younger women(born after 1990,n=200).Samples were collected at five time-points;week 36 of pregnancy,birth(cord),and 3,6,and 9 months after birth.Measles-specific IgG antibody levels were recorded.Results:In total,77.06% of the 401 pregnant women were seropositive for measles-specific IgG antibodies.A significantly greater proportion of mothers aged 30 and older(88.06%)and their newborn(93.53%)were seropositive compared to the mothers aged 25 and younger(66.00%),and their newborn(72.00%)(P<0.001).The infants of older mothers had significantly higher geometric mean titres(GMT)of measles IgG antibodies than the infants of younger mothers(P<0.001)at all time-points of the study period.The proportion of measles IgG antibodies together with GMT decreased from 82.97%(506.96)at the age of three months to 23.19%(45.22)at the age of nine months.Conclusions:This study provides a profile of maternal antibodies against measles in Vietnamese infants and investigates the early susceptibility to measles in both the infants of vaccinated mothers and mothers with naturally acquired immunity.These data suggest that determining the appropriate age for measles vaccination is paramount for the elimination of measles in Vietnam.