Rubella Immunization Research Articles

Impact of vaccine effectiveness and coverage on preventing large mumps outbreaks on college campuses: Implications for vaccination strategy

Recent mumps outbreaks among highly vaccinated populations, including college students, have called into question the vaccine effectiveness (VE) of routine two-dose measles, mumps, and rubella (MMR2) immunization. We aimed to estimate the VE required for a novel vaccination strategy (e.g., MMR booster dose, novel vaccine) to prevent large mumps outbreaks on college campuses. Using mumps college outbreak data reported to the U.S. Centers for Disease Control and Prevention during 2016–2017, we estimated current MMR2 VE using the screening method and implemented a compartmental model of mumps transmission. We performed 2000 outbreak simulations, following introduction of an infectious person to a population of 10,000, over ranges of MMR2 vaccine coverage (VC) and VE (30.0–99.0%). We compared the impact of varying VC and VE on mumps and mumps orchitis case counts and determined VE thresholds that ensured < 5.0% and < 2.0% of the outbreak simulations exceeded 20 and 100 mumps cases. Median estimated MMR2 VE in reported mumps outbreaks was 60.5% and median reported MMR2 VC was 97.5%. Simulated mumps case count was more sensitive to changes in VE than in VC. The opposite was true for simulated mumps orchitis case count, though orchitis case count was small (mean <10 cases across simulations for VE near 60.5% and VC near 97.5%). At 97.5% VC, 73.1% and 78.2% VE were required for < 5.0% and < 2.0% of outbreaks, respectively, to exceed 100 mumps cases. Maintaining 97.5% VC, 82.4% and 85.9% VE were required for < 5.0% and < 2.0% of outbreaks, respectively, to exceed 20 cases. We conclude that maintaining current levels of MMR2 VC, a novel vaccination strategy aimed at reducing mumps transmission must achieve at least 73.1–85.9% VE among young adults to prevent large mumps outbreaks on college campuses.

Leveraging a national biorepository in Zambia to assess measles and rubella immunity gaps across age and space

High-quality, representative serological surveys allow direct estimates of immunity profiles to inform vaccination strategies but can be costly and logistically challenging. Leveraging residual serum samples is one way to increase their feasibility. We subsampled 9854 residual sera from a 2016 national HIV survey in Zambia and tested these specimens for anti-measles and anti-rubella virus IgG antibodies using indirect enzyme immunoassays. We demonstrate innovative methods for sampling residual sera and analyzing seroprevalence data, as well as the value of seroprevalence estimates to understand and control measles and rubella. National measles and rubella seroprevalence for individuals younger than 50 years was 82.8% (95% CI 81.6, 83.9%) and 74.9% (95% CI 73.7, 76.0%), respectively. Despite a successful childhood vaccination program, measles immunity gaps persisted across age groups and districts, indicating the need for additional activities to complement routine immunization. Prior to vaccine introduction, we estimated a rubella burden of 96 congenital rubella syndrome cases per 100,000 live births. Residual samples from large-scale surveys can reduce the cost and challenges of conducting serosurveys, and multiple pathogens can be tested. Procedures to access quality specimens, ensure ethical approvals, and link sociodemographic data can improve the timeliness and value of results.

The Relationship of Mom's Knowledge about the Importance of Measles Rubella (MR) Immunization with Compliance with Immunization

Measles and Rubella are kinds of infectious diseases through the airway that cased by virus of measles and Rubella (MR) and the immunization of measles and rubella (MR) will be one immunization to avoid the disease . This research is taken to know the correlation of mothers knowledge about Measles and Rubella Immunization in Hospitalized local government clinic of Gunungtua, North Padang Lawas Regency in the year 2021. Type of this research is quantitative research with descriptive correlation design and it is taken by cross sectional study approaches. This research is taken place at the local Government clinic unit Hospitalized Gunungtua, North Padang Lawas Regency. The population and sample of this research are coming from the mothers who have child on 9 months age until &lt;15 old years, that are about 122 people. The results of this research show that got about p-value 0.000 &lt;0.05, Its means that there is a significant correlation between knowledge with subservience in having Immunization of Measles Rubella (MR) int the Local Government Clinic Unit Hospitalized Gunungtua, North Padang Lawas Regency. The suggestions is the Healthy servant should give information as well as education for the society about the immunization of Measles Rubella (MR).

Risk Factors for Measles Nonimmunity in Rubella-Immune Pregnant Patients.

Measles immunity testing, unlike that for rubella, is not currently part of prenatal screening even though immunity to both is conferred by the measles-mumps-rubella (MMR) vaccine. Although endemic transmission of measles was declared eliminated in the United States in 2001, outbreaks have continued to occur. Given the risks associated with measles infection during pregnancy, we sought to identify risk factors for measles nonimmunity (MNI) in rubella-immune (RI) pregnant individuals. We performed a retrospective observational cross-sectional study of patients receiving prenatal care and delivering at two university hospitals and a county hospital in Southern California from April 1, 2019 to February 1, 2021. Inclusion criteria were pregnant individuals ≥18 years old who had serological testing for rubella and measles during pregnancy. Demographic data were extracted from electronic medical records, including results of serological testing and chronic medical conditions. All subjects were rubella immune, and we compared measles-immune (MI) with MNI groups. In total, 1,813 RI individuals were identified, with 1,467 (81%) MI and 346 (19%) MNI individuals. Variables associated with an increased risk of MNI included having public health insurance (adjusted relative risk [aRR]: 1.56; 95% confidence interval [CI]: 1.24, 1.97) and Hispanic ethnicity (aRR: 1.37; 95% CI: 1.06, 1.78). Black race was associated with a decreased risk of MNI (aRR: 0.52; 95% CI: 0.29, 0.91). Birth year before 1989 demonstrated a trend toward increased risk of MNI, but this did not reach statistical significance (aRR 1.23; 95% CI: 1.00, 1.52). No differences were seen between the two groups for medical comorbidities. Our study is the first to demonstrate risk factors for measles MNI in patients with documented rubella immunity. In the absence of universal measles serological screening recommendations, the risk factors identified could help guide clinicians in selective screening for those at risk of needing postpartum MMR vaccination. · The rate of measles nonimmunity is higher than previously reported.. · Hispanic ethnicity and use of public insurance are risk factors for measles nonimmunity.. · The current recommendation for history-based screening for measles immunity is likely insufficient..

Lessons from Ten Years' the Prevalence of Congenital Rubella Syndrome (CRS) in the Young Population Living in a Developing Country, Tehran; Iran.

A safe and effective rubella vaccine is available and prescribed in IRAN. This is a survey of CRS cases collected based on WHO criteria one decade after the MR vaccination campaign (2003). This Multi-stage prospective/cross-sectional study was carried out in three stages in 3 educational hospitals in Tehran (Rasoul Aram, Akbar Abadi, and Firoozabadi), In the first stage of the study between 2011 and 2012 total of 186 infants were evaluated, and in the second stage of the study, total 163 blood samples of infants with suspected INTRA UTERINE INFECTION were compared with a group of healthy matched infants. In the first and second stages, Rubella immunity (IgG&IgM) in cord blood was evaluated by the Eliza method. Despite MR vaccination in Iran, after one decade"confirmed CRS" and " compatible CRS" was diagnosed in 5 and 31 from 89 CRS suspected cases. The incidence of "confirmed CRS" in every 100 CRS suspected infants (after campaign) is 5.6 %, and 31 CRS Compatible cases are so important. Without active CRS surveillance, mild infection such as IUGR, hearing loss, heart abnormalities, impaired vision, and mental retardation even in the developed country might be missed. Fetal infection is persistent, which imposes additional costs on the country. Another mass vaccination in women and girls is needed. Also, the anti-rubella IgG testing before pregnancy in women who were not vaccinated; vaccination of women before marriage /pregnancy should be obligatory in order to prevent the CRS.

Susceptibility to Rubella Infection and Incidence of Congenital Rubella Infection: 6 Years Retrospective Study.

IntroductionRubella is considered one of the most serious and most common congenital infections. Despite global efforts for elimination, rubella cases are still being reported in many parts of the world. The purpose of this study is to determine the level of immunity to rubella in the community and most importantly among women at childbearing age in the eastern province of Saudi Arabia and compare it with the target set by the World Health Organization (WHO) along with the incidence of acute rubella infection and the associated congenital rubella infection and congenital rubella syndrome.MethodsThis is a retrospective cross-sectional study over the six years period (Jan 2014–Jun 2020) on all individuals tested for rubella IgM and IgG in a university teaching hospital.ResultsNighty one percent (15,894/17,469) of the population tested showed evidence of rubella immunity with 8.8% (1546/17,469) being susceptible. Among women at childbearing age, susceptibility to rubella was higher with 9.2% (1220/13,278) of women showing no evidence of immunity. In addition, acute rubella infection was reported for 0.17% (29/17,469) of the population tested and 0.15% (20/13,278) in women at childbearing age. No cases of congenital rubella infection were reported in the study period.DiscussionThe level of Rubella immunity in the population is 91% and is less than the WHO target for rubella control therefore, risk of resurge of cases is present, indicating the need for continued national surveillance and more efforts to improve vaccination coverage in the kingdom.

Effectiveness of immunization activities on measles and rubella immunity among individuals in East Sepik, Papua New Guinea: A cross-sectional study

ObjectivesThis study aimed to assess measles and rubella immunity by measuring virus-specific immunoglobulin G (IgG) prevalence among individuals and evaluate the effectiveness of recent supplementary immunization activities (SIAs) by comparing the antibody positivity rates of the SIA target age groups in 2015 with those in 2019 as measles and rubella are endemic in Papua New Guinea. MethodsA cross-sectional study. The measles- and rubella-specific IgG levels of patients aged ≥1 year at two clinics in East Sepik province, Papua New Guinea were assessed with commercially available virus-specific IgG EIA kits. ResultsIn total, 297 people participated in the study and 278 samples with sufficient volume, relevant information, and age inclusion criteria were analyzed. The overall IgG prevalence rates were 62.6% for measles and 82.0% for rubella. The age groups targeted in the 2019 SIAs had a higher IgG prevalence than those targeted in the 2015 SIAs for both the infectious diseases. Moreover, the IgG prevalence for rubella was higher than measles in these groups. ConclusionsThe anti-measles and anti-rubella IgG prevalence in the target groups were lower than those required for herd immunity. The immunization program should be emphasized to eliminate measles and rubella. Further population-based studies are warranted.

Innovations in vaccine delivery: increasing access, coverage, and equity and lessons learnt from measles and rubella elimination.

Disease eradication and elimination programs drive innovations based on progress toward measurable objectives, evaluations of new strategies and methods, programmatic experiences, and lessons learned from the field. Following progress toward global measles elimination, reducing measles mortality, and increasing introductions of measles and rubella vaccines to national programs, the measles and rubella immunization program has faced setbacks in recent years. Currently available vaccine delivery methods have complicated logistics and drawbacks that create barriers to vaccination; innovations for easier, more efficient, and safer vaccine delivery are needed. Progress can be accelerated by new technologies like microarray patches (MAPs) that are now widely recognized as a potential new tool for enhancing global immunizations efforts. Clinical trials of measles-rubella vaccine MAPs have begun, and several other vaccine MAPs are in the pre-clinical development pathway. MAPs could significantly contribute to Immunization Agenda 2030 priorities, including reaching zero-dose children; increasing vaccine access, demand, coverage, and equity; and achieving measles and rubella elimination. With strong partnerships between public health agencies and biotechnology companies, translational novel vaccine delivery systems can be developed to help solve public health problems and achieve global health priorities.

Analysis of the Implementation of the Measles Rubella (Mr) Immunization Program in Preschool Age Children 3-6 Years in Gorontalo Regency

The purpose of this research is to identify the characteristics that contribute to the effective implementation of a measles rubella (MR) vaccination program in preschool children aged 3-6 years in the Gorontalo District. The purpose of this study is to collect comprehensive data on the implementation of the measles rubella (MR) vaccination program in preschool children, particularly in Limboto District, Gorontalo Regency, as measured by communication, resources, monitoring evaluation, perception, attitude, and anxiety. The research method employed is survey. The stages of the activities are as follows: survey activities on-site, data gathering, and data processing. The research period runs from the start of the year to the conclusion of the implementation year. The statistical analysis revealed a link between communication factors, perceptions, attitudes, and anxieties, but no association between resource variables and assessment monitoring and the execution of the MR vaccination program. Then, the findings of multivariate analysis on each variable are used to create the final modeling that is most closely connected to the application of MR immunization.

Parity status and the relationship between antenatal rubella serology with obstetric outcome

Routine antenatal rubella serological testing is adopted in many countries. In a population covered by universal childhood rubella immunization for four decades, we have observed an association between pre-eclampsia with maternal rubella seronegativity among multiparous gravidae. This retrospective cohort study was further performed to elucidate the interaction between parity status and rubella seronegativity on obstetric outcome in singleton pregnancies carried to ≥ 24 weeks gestation managed from 1997 to 2019, with the data retrieved from a computerized database used for annual statistics and auditing. Of the 133,926 singleton pregnancies eligible for the study, the 13,320 (9.9%) rubella seronegative gravidae had higher mean booking weight and body mass index (BMI), but shorter height, and higher incidence of advanced age (≥ 35 years), high BMI, short stature, and lower incidence of nulliparas. Univariate analysis showed that adverse obstetric outcomes were more frequently found among the multiparas. On multivariate analysis, there was increased postdated (> 41 weeks) pregnancy irrespective of parity status, while nulliparas had reduced gestational hypertension (aRR 0.714, 95% CI 0.567–0.899) and gestational diabetes (aRR 0.850, 95% CI 0.762–0.950), and multiparas had increased pre-eclampsia (aRR 1.261, 95% CI 1.005–1.582), neonatal death (aRR 2.796, 95% CI 1.243–6.291), and perinatal death (aRR 2.123, 95% CI 1.257–3.587). In conclusion, in a population covered by universal childhood rubella immunization, antenatal rubella seronegativity is associated with increased pre-eclampsia and perinatal loss only in multiparas, suggesting that the rubella seronegativity in these women served as proxy for some form of altered immune response which increases adverse pregnancy outcome.

An equity-based assessment of immunization-related responses in urban Alberta during the 2014 measles outbreak: a comparative analysis between Calgary and Edmonton.

This study investigates measles, mumps, and rubella (MMR) immunization rates during the measles outbreak in Calgary and Edmonton of 2014 stratified by four area-level socio-demographic indicators. This study also leverages this epidemiological data to assess the equity aspect of emergency measures instituted regarding immunization in those two cities. A mixed-methods comparative case study analysis methodology was employed to assess the neighbourhood-level immunization statuses before (2013), during (2014), and after (2015) an active measles outbreak in Calgary and Edmonton, Alberta, Canada. The epidemiological one-dose by age-2 MMR coverage data were stratified using four socio-demographic indicators: median household income, %-homeownership, %-Aboriginal population, and %-immigrant population. Document and content analysis was utilized to investigate the outbreak mitigation strategies deployed in each city. The measles outbreak of 2013/2014 involved the entirety of Alberta and led to both provincial and city-specific interventions in which Calgary deployed three mass immunization clinics in 2014, where Edmonton did not. The Calgary coverage data showed an increase in coverage inequalities across all indicators and the Edmonton data showed mixed results in terms of equity gains/losses. Calgary's additive intervention of three mass immunization clinics in 2014 appears to have contributed to both the higher gross immunization rates in Calgary (90.77%) and an inequitable increase in coverage rates as compared with Edmonton (88.96%), in most cases. Public health policy-makers must be cognizant that large-scale public health efforts must be optimized for accessibility across all socio-economic levels to ensure public and population health gains are realized equitably.

THE ROLE HEALTH OFFICERS AS A DETERMINING FACTOR FOR THE SUCCESSFUL MEASLES RUBELLA IMMUNIZATION IN THE WORK AREA OF THE RAWANG HEALTH CENTER, PADANG CITY

Background: The measles rubella (MR) immunization coverage rate in Padang City is only 30.82%, still far below Indonesia's national target of 95%. The coverage of measles rubella immunization at the Rawang Health Center is around 62.1%. This study aims to determine the role of health workers in the success of measles rubella immunization in the Rawang Public Health Center, Padang City. Methods: This study used a cross sectional design. The study was conducted in October 2018-July 2019. The research population is mothers who have children aged 12-59 months (toddlers) as many as 1807 respondents. The sampling method is proportional random sampling with a sample of 87 respondent. Data was collected by interview using a questionnaire. Results: The results showed that 37.9% of children under five had not been immunized against measles rubella and 44.8% of health workers had an unfavorable role. The results of the chi-square test showed a significant relationship between the role of officers in the success of measles rubella immunization (p-value=0.020). Recommendation: It is hoped that health workers can increase health promotion activities regarding the risks due to children not being immunized against measles rubella and intensify door-to-door programs in the implementation of measles rubella immunization

Rubella immunity in native Turkish and Syrian immigrant pregnant women between 2010-2018

Objectives: The study has aimed to investigate the rubella immunity in native-Turkish and Syrian-immigrant pregnant women in Turkey. Methods: Between September 2010 and December 2018, the hospital records of pregnant patients were evaluated retrospectively. For each year, for the number of patients who were screened for rubella IgG and/or IgM antibodies, IgG avidity (if any), and PCR tests (if any) were investigated, and subjects were categorized by nationality. Results: During the study period, a total of 80,302 pregnant were tested with at least one of the rubella IgM or IgG antibodies. Of these, 22,962 pregnant women were screened for both IgG and IgM, 24,684 were screened for IgG, and 78,580 pregnant women were screened for IgM rubella antibodies. The seropositivity rate of IgG rubella antibodies in native and Syrian pregnant groups was 93.8% and 95.9%, respectively. In both groups, the IgM rubella antibodies were found as 0.5%. IgG avidity was investigated in 252 patients, whose test results were positive for IgM and IgG; and a low IgG avidity was detected in 5 native patients, while none was detected in the Syrian group. Conclusions: In the Syrian immigrant group, the susceptibility to Rubella is low, and it does not differ from the native Turkish population.

Rubella Immunity among Pregnant Women in Bangui, Central African Republic

Sero-positivity rates of the rubella virus among pregnant women vary from country to country widely throughout the world. In the Central African Republic, rubella vaccination is not included in the national immunization schedule. Thus, we propose to evaluate the immune status of pregnant women. This was an analytical retrospective study that consulted the records of pregnant women received in prenatal consultations at the Bangui Community Hospital maternity ward from January to December 2020. Socio-demographic and laboratory data (IgM, IgG) were collected from January to June 2021. Chi2 test was used. A total of 289 pregnant women were analyzed. Women with an IgM+ response accounted for 4.15%. Those with an IgG+ were 14.87%. The distribution by age group shows that patients aged 20 - 24 and those aged 25 - 29 had a rubella profile suggesting persistent infection (p = 0.010). The average age of women included was 28 (±6) years. The average parity for the entire sample was 2.18 (1.93). At any age pregnant women were not significantly exposed to rubella infection (p = 0.96), (ORbrut = 1.03; CI95% = [0.32 - 3.34]). Both immunized and non-immunized individuals are similarly exposed [OR = 0.86; 95% IC95% = 0.44 - 1.68] with no difference (p = 0.96). Rubella infection remains particularly severe when it occurs during pregnancy. It would be wise to seek immunity in all girls of childbearing age in order to rule out any risk of rubella embryopathy.

Improving Immunization Rates During the 2019 Measles Outbreak.

In 2019, there were multiple outbreaks of measles in the United States. In the context of the public awareness of these outbreaks, we performed an intervention with the intent to improve the rate of measles immunization in our pediatric population. Pediatric patients that were lacking adequate measles immunization were identified by electronic medical record (EMR) survey. Charts were reviewed and updated if records were found to be incomplete. Parents of the remaining children were sent a letter, personally signed by the child’s primary care provider, encouraging measles immunization. A measles fact sheet, produced by the United States Center for Disease Control, was also included with the letter. There were 44 patients in the study group whose parents received a letter and measles fact sheet. As a result, 5 of these children were brought in for a measles, mumps, and rubella (MMR) immunization. The 44 patients whose parents received a letter included 20 patients whose parents had previously expressed intent to not vaccinate their children as documented in the EMR. None of these children received an MMR immunization. Although small in scope, this project provides a glimpse into the importance of personal provider guidance to parents who are inclined to immunize their children. Unfortunately, it also demonstrated that provider advice did not change the opinions of parents who had already taken a stance against vaccination, even in the context of an urgent public health situation that had garnered widespread coverage in the lay press and social media.

THE RESPONSE OF PESANTREN COMMUNITY IN MAGELANG TO THE IMPLEMENTATION OF MEASLES RUBELLA IMMUNIZATION

This paper is aimed to determine the response of the pesantren community in Magelang-Indonesia to the Measles Rubella (MR) immunization law in 2017. Moreover, this paper was more focused on the investigation for the elements that is influencing the emergence of pro-contra attitudes among the pesantren community in Magelang-Indonesia toward the MR Rubella immunization law. The author used a sociology approach. Data obtained through observation, interview and literature study. The author used deductive-inductive methods and critical reflection to analyze the data. The article presents the conclusion of research that the pesantren community response in Magelang to inplementation of immunization and vaccination occurred pros and cons. Groups who reject immunization argue that immunization is against religious law. Meanwhile, the group receiving immunizations argues that immunization is important and emergencies in ensuring the health of children to avoid the disease that will result from not being immunized. So is the perspective of world religions. Essentially Islam, Protestant, Hindu and Jewish receive immunization as an effort to ensure the health of children. While Catholics and Buddhism tend to reject immunization

HUBUNGAN PERAN KADER KESEHATAN DAN GURU DENGAN IMPLEMENTASI IMUNISASI MR (MEASLES RUBELLA) DI WILAYAH KERJA PUSKESMAS TALAGA JAYA KABUPATEN GORONTALO

Measles Rubella immunization is combination of Measles and Rubella vaccine for protection against Measles and Rubella. The objective of research was to determine the relationship of nurse officer roles and teacher with the implementation of Measles Rubella immunization. The design used analytic quantitative survey with cross sectional approach. Sampling technique used Total sampling with 42 samples of nurse officer and teacher. Analysis used chi square with the significant = 0,05, the result obtained there is relationship between nurse officer with the implementation of MR immunization with ρ = 0,026 &lt; 0,05, and also there is relationship between teacher with the implementation of MR immunization with ρ = 0,022 &lt; 0,05.

How Australia's measles control activities have catalyzed rubella elimination

BackgroundBy 2017, rubella had been officially eliminated in Australia. This success was attributed to Australia's longstanding national immunization programme and two enhanced measles immunization activities using measles, mumps, and rubella (MMR) vaccines — the Measles Control Campaign (MCC) and the Young Adult MMR Campaign (YAC). Our study describes the impact of these activities on rubella incidence, and its elimination in Australia. MethodsAggregate national serological survey data were assigned to birth cohorts, and mean, median, and age-group estimates calculated and analyzed against MMR immunization coverage estimates (1998–2018) and rubella notifications (1993–2018). Three-year cumulative incidences were calculated by birth cohort. ResultsThe serological surveys revealed high and stable levels of rubella immunity among females, but estimates for three male cohorts were lower. Since 2007, MMR immunization coverage among children aged 24–27 months has remained above 90% for both doses. The 3-year cumulative incidence of rubella declined across all birth cohorts following the MCC and the YAC. DiscussionUsing MMR vaccines to address measles immunity gaps had the additional benefit of controlling rubella in Australia. Both the MCC and YAC shifted rubella epidemiology, accelerating the interruption of endemic transmission. Countries should consider combined measles and rubella vaccines for all catch-up activities.

Catch-up immunization for adolescents and young adults during pre-travel consultation in Japan.

Rubella and measles outbreaks in adults occur because of unimmunized or partially immunized status. Travel clinics play an important role in catch-up measles, rubella, mumps, and varicella immunization for adults. We evaluated the need for catch-up measles, rubella, mumps, and varicella immunization by young adults at our travel clinic. This retrospective observational study was conducted at the National Center for Global Health and Medicine from June 1, 2017 to May 31, 2018. Adults aged 16–49 years who received pre-travel consultation and had childhood immunization records were included. Individuals who fully or partially received planned measles, rubella, mumps, and varicella catch-up immunization were classified as “immunized.” We calculated the proportion of “immunized” individuals and analyzed the factors associated with catch-up measles, rubella, mumps, and varicella immunization at pre-travel consultation using logistic regression analysis. Overall, 3,456 individuals received pre-travel consultations during the study period; 827 (336 men, median age 22 years) had childhood immunization records. The most common trip purposes were study (33%) and tourism (24%). The most common destination was Asia (39%). Catch-up immunization of any measles, rubella, mumps, and varicella vaccine was needed by 755 individuals. After consultation, 20–46% of these participants who needed catchup immunization received at least one dose of immunization. Factors that are negatively associated with measles, rubella, mumps, and varicella catch-up immunization were tourism (odds ratio 0.37 to 0.58), yellow fever vaccination (0.45 to 0.50) (excluding varicella), and each disease history (0.13 to 0.40) (excluding rubella and varicella). Further studies are needed to identify barriers to catch-up immunization.

High seroprevalence of rubella in Thai children with a 2-dose MMR national immunization policy

Rubella is generally a mild disease, but infection during pregnancy can cause congenital rubella syndrome. Thailand has implemented a two-dose MMR vaccination policy since 2010. This study aimed to describe the seroprevalence rate of rubella among children and adolescents in Thailand. We conducted a cross-sectional study of 132 healthy children (aged 3–9 years) who had received 2 doses of rubella vaccine and 424 adolescents (aged 10–18 years) who were expected to receive at least 1 dose of rubella vaccine. Stored serum samples from healthy children and recently drawn serum samples from adolescents were tested for rubella IgG antibody using a commercial enzyme-linked immunosorbent assay (ELISA) kit (EUROIMMUN). Seroprotection was defined as a rubella IgG level ≥ 10 IU/mL. The rubella seroprevalence rate among children and adolescents who had 2 documented doses of MMR was 97.0% (95 %CI 92.5–99.2%) and 85.4% (95% CI 78.8–90.6%, p < 0.01) respectively. The geometric mean titer of rubella was higher in children, 38.3 (95% CI 33.5–43.9) compared to adolescents, 22.5 (19.4–25.9) IU/mL. We observed an inverse correlation between the rubella titer and time interval from the second rubella containing vaccine dose (R = -0.30, p < 0.01). A 2-dose MMR vaccination course produces a high seroprevalence of rubella immunity in children, which decreases with time, suggesting waning of immunity.Thai clinical trials registry number TCTR20191120001.