Rubella Antibody Titers Research Articles

Seroprotection of Measles, Rubella, Pertussis and its Relation with Occurrence of COVID-19 among a Cohort of University Female Students

Background:: Antibody titres against several infections are hypothesized to be protective against COVID-19 due to cross-immunity. The study intends to assess the relationship between historical data on measles, rubella, pertussis antibody titres and the occurrence of self-reported COVID-19. Methods:: The study was conducted as an online cross-sectional survey which was compared with historical data of antibody titers. The university female students who had participated in our previous study evaluating seroprevalence of measles, rubella and pertussis antibody titres were contacted online for the survey. The online questionnaire was sent to collect details on COVID-19 occurrence among all the participants. The measles, rubella and pertussis titers of all participants were correlated with the present questionnaire data. All volunteers participated in the survey after online informed consent. Results:: Among the 52 responders to the questionnaire, 18 participants had been reported to be suffering from COVID-related symptoms and 12 were reported to have confirmed RT-PCR positive for COVID-19. The unpaired “t” test comparing antibody titres of measles, rubella and pertussis between COVID-19 RT PCR positive and RT PCR negative subjects did not show statistical significance. Conclusion:: There was no statistical difference between antibody titers of measles, rubella and pertussis among self-reported COVID-19 RT PCR positive and RT PCR negative university female students.

Factors Predicting Rubella Vaccination and Antibody in Pregnant Women in Japan: A Report from Pregnant Women Health Initiative.

This study aimed to identify the factors predicting rubella vaccination status based on self-reported data and the presence of sufficient rubella antibody titers in pregnant women in Japan. We used the results of the nationwide questionnaire survey conducted at obstetric facilities in the Pregnant Women Health Initiative Project (PWHI), with 23 participating hospitals recruiting pregnant women from June 2018–November 2019. We extracted age, the number of deliveries, educational level, household income, pre-pregnancy smoking, and knowledge of rubella from questionnaires and medical records. We analyzed the association of rubella vaccination status and antibodies with each of these factors. We found that the number of previous deliveries, educational level, annual household income, smoking before pregnancy, and knowledge of rubella were factors predicting self-reported rubella vaccination status, while age and the number of previous deliveries were identified as factors predicting the presence of sufficient rubella antibody titers (32 folds or higher). Women considering pregnancy should be immunized against rubella to prevent congenital rubella syndrome in the future. Furthermore, social policies are needed to strongly encourage vaccination, especially for all citizens who were not given the opportunity or missed the chance to be vaccinated against rubella.

Prevalence of rubella antibodies: comparison between women with pregnancy induced by infertility treatments and those with spontaneous pregnancy.

SummaryWidespread rubella epidemics have sometimes occurred in Japan. We compared the prevalence of rubella antibodies in women who had conceived after infertility treatments and in those who had conceived spontaneously. We reviewed the obstetric records of nulliparous Japanese women who had conceived after infertility treatments and whose babies had been born at the Japanese Red Cross Katsushika Maternity Hospital from 2014 to 2018. No significant differences in the rates of women with rubella antibody titers < 8 or < 32 emerged between those who had been treated and those who had not (titer < 8: 4.1 vs. 3.4%, p = 0.58; titer < 32: 17.3 vs. 15.3%, p = 0.45, respectively). It is necessary to thoroughly implement pre-conception care concerning the risk of congenital rubella infection for women undergoing infertility treatments, especially in Japanese obstetric clinics.

Impact of vaccination on measles, mumps, and rubella antibody titers in Japanese healthcare workers: An observational study.

Given the complicated history of Japan’s National Immunization Program, a significant proportion of Japanese people including healthcare workers (HCWs) still lack adequate immunity against measles, mumps, and rubella (MMR), resulting in occasional outbreaks. In 2014, the Japanese Society of Infection Prevention and Control (JSIPC) published vaccination guidelines for HCWs. We evaluated antibody titers before and after MMR vaccination in HCWs at the Nara Medical University Hospital, the attainment rate of the target antibody titers defined by the JSIPC guidelines, and the safety of vaccines. We measured MMR antibody titers in HCWs, followed by inoculation with the respective monovalent vaccines and/or trivalent MMR (tMMR) vaccine according to the JSIPC guidelines. Among 467 HCWs evaluated, antibody titers against measles and mumps measured using the IgG-enzyme immunoassay increased from 11.0 [interquartile range (IQR): 8.0–13.6] to 13.7 (IQR: 11.3–16.9; P < 0.001) and from 2.8 (IQR: 2.1–3.5) to 4.8 (IQR: 3.7–5.7; P < 0.001), respectively. By evaluating a logarithmic value of log2(X + 1) converted from an antibody titer X, antibody titers against rubella measured using the hemagglutination assay increased from 3.2 (IQR: 0–4.1) to 6.0 (IQR: 4.6–8.0; P < 0.001). Antibody titer elevated following tMMR vaccination was lower than that following monovalent vaccination in a single dose of the measles-containing, a single dose of the mumps-containing, and two doses of rubella-containing vaccine groups (P = 0.01, 0.01, and <0.001, respectively). After vaccination, 20.0%, 61.5%, and 46.2% of HCWs attained target antibody titers specified by the JSIPC guidelines for measles, rubella, and mumps, respectively. The systemic response in female HCWs who underwent monovalent mumps vaccination was statistically higher than that in others. Although the vaccination program for HCWs according to the JSIPC guidelines caused increased MMR antibody titers, the rates of attaining the target criteria were low.

Transcriptomic profiling of different responder types in adults after a Priorix® vaccination

Thanks to the recommendation of a combined Measles/Mumps/Rubella (MMR) vaccine, like Priorix®, these childhood diseases are less common now. This is beneficial to limit the spread of these diseases and work towards their elimination. However, the measles, mumps and rubella antibody titers show a large variability in short- and long-term immunity. The recent outbreaks worldwide of measles and mumps and previous studies, which mostly focused on only one of the three virus responses, illustrate that there is a clear need for better understanding the immune responses after vaccination. Our healthy cohort was already primed with the MMR antigens in their childhood. In this study, the adult volunteers received one Priorix® vaccine dose at day 0. First, we defined 4 different groups of responders, based on their antibody titers’ evolution over 4 time points (Day 0, 21, 150 and 365). This showed a high variability within and between individuals. Second, we determined transcriptome profiles using 3′mRNA sequencing at day 0, 3 and 7. Using two analytical approaches, “one response group per time point” and “a time comparison per response group”, we correlated the short-term gene expression profiles to the different response groups. In general, the list of differentially expressed genes is limited, however, most of them are clearly immune-related and upregulated at day 3 and 7, compared to the baseline day 0. Depending on the specific response group there are overlapping signatures for two of the three viruses. Antibody titers and transcriptomics data showed that an additional Priorix vaccination does not facilitate an equal immune response against the 3 viruses or among different vaccine recipients.

Long-term immunogenicity of measles, mumps and rubella-containing vaccines in healthy young children: A 10-year follow-up

Measles and mumps outbreaks still occur in countries that have successfully implemented universal routine immunization programs. Measles outbreaks are mostly associated to absent or incomplete vaccination, whereas for mumps outbreaks the combined effects of waning of immunity and circulating new strains are incriminated. It is therefore increasingly useful to characterize the long-lasting immunity induced by measles-, mumps, and rubella (MMR)-containing vaccines.In this 10-year study, 1887 healthy children aged 12–22 months, randomized to receive 1 or 2 doses of MMR-containing vaccines (Priorix or Priorix-Tetra; GSK), were included in an antibody persistence analysis. A total of 364 children in the 1-dose group received a second dose out of study according to their local vaccination schedule between Years 4 and 10 post-dose 1, and were included in a separate post-hoc analysis to evaluate the effect of the second dose when given later. Anti-measles, -mumps and -rubella antibody titers were measured by commercial ELISA kits (Enzygnost, Siemens) after each vaccine dose and at Years 1, 2, 4, 6, 8 and 10 post-vaccination.Antibodies against measles and rubella declined moderately after vaccination but remained well above the seropositivity threshold after 10 years. The anti-measles antibody titers elicited by Priorix-Tetra remained about 2-fold higher throughout the study as compared with Priorix. A second dose of MMR vaccine later in life had a minor and transient effect on anti-measles and anti-rubella waning titers. In contrast, anti-mumps antibody levels remained relatively stable over the 10-year follow-up and a second dose of MMR vaccine, given anytime over the 10-year period, had a boosting effect on anti-mumps antibody titers and seropositivity rates.In conclusion, 1 or 2 doses of MMR-containing vaccines given to children in their second year of life induced antibody responses against measles, mumps and rubella viruses that persisted at least up to 10 years post-vaccination.Clinical trial registration number: NCT00226499.

Rubella virus neutralizing antibody response after a third dose of measles-mumps-rubella vaccine in young adults

BackgroundThird doses of measles-mumps-rubella (MMR) vaccine have been administered during mumps outbreaks and in various non-outbreak settings. The immunogenicity of the rubella component has not been evaluated following receipt of a third dose of MMR vaccine. MethodsYoung adults aged 18–31 years with documented two doses of MMR vaccine received a third dose of MMR vaccine between July 2009 and October 2010. Rubella neutralizing antibody titers were assessed before, 1 month, and 1 year after receipt of a third dose of MMR vaccine. ResultsAmong 679 participants, 1.8% had rubella antibody titers less than 10 U/ml, immediately before vaccination, approximately 15 years after receipt of a second dose of MMR vaccine. One month after receipt of a third dose of MMR vaccine, average titers were 4.5 times higher and >50% of participants had a 4-fold boost. Response was highest among those with titers less than 10 U/ml prior to vaccination (geometric mean titer ratio = 18.8; 92% seroconversion) and decreased with increasing pre-vaccination titers. Average titers declined 1 year postvaccination but remained significantly higher than pre-vaccination levels. The proportion classified as low-positive antibody levels increased from 3% 1 month postvaccination to 24% 1 year postvaccination. ConclusionsVaccination with a third dose of MMR vaccine resulted in a robust boosting of rubella neutralizing antibody response that remained elevated 1 year later. Young adults with low rubella titers are more likely to benefit from a third dose of MMR vaccine.

Relationship between Self-Reported Vaccination History and Measles and Rubella Antibody Titers in Medical and Nursing Students

In hospitals, infection control for measles and rubella is important. Medical and nursing students as well as healthcare workers must have immunity against these diseases. Many countries have adopted requirements for healthcare workers’ documented vaccination history or laboratory tests as evidence of their immunity. Evaluating a written vaccination history is difficult in many cases. Therefore, we compared measles and rubella antibody titers with self-reported vaccination history and we evaluated the association between the history and measles and rubella antibody titers, using the medical and nursing students’ data. We analyzed 564 data for measles and 558 data for rubella. Vaccination history was requested to be completed as accurately as possible. Students with one or more measles or rubella vaccinations had high positive ratios of titer, and the ratio was significantly higher than that of the students without vaccinations. The positive ratio between the two-dose and one-dose vaccination groups was not significantly different for measles or rubella (measles: p = 0.534, rubella: p = 0.452). Although it should be requested that the history is complete by using other resources, such as referring to maternity passbooks or proof of vaccination, self-reported history may be useful to confirm immunity, even if there is a possibility that the history is not accurate.

Humoral immunity to tetanus, measles and rubella in children with acute lymphoblastic leukemia after chemotherapy.

Chemotherapy regimens and clinical support advances have improved survival in children with acute lymphoblastic leukemia. The after-effects of treatment are a reason for concern, including damage to the immune system induced by immunosuppressive therapy which is reflected in the loss of antibody protection provided by prior immunizations. Our goal was to assess the presence of measles, rubella, and tetanus protective antibody titers among patients with acute lymphoblastic leukemia after completing chemotherapy. Sixty-one children with acute lymphoblastic leukemia seen at the Hospital Garrahan were included; patients had finished their chemotherapy at least 6 months earlier and had a complete immunization schedule before diagnosis. The rates of protective antibodies were 46% (CI: 32-59) for measles, 53% (CI 40-67) for tetanus, and 60% (CI 47-63) for rubella. These results strengthen the need to reconsider revaccination in this group of patients.

Comparing the rubella seronegativity in pregnant women who received one dose of rubella vaccine at different ages in Taiwan

IntroductionVaccination is the best strategy to prevent rubella and congenital rubella. The aim of our study was to assess the immunity to rubella and determine rubella virus antibody titers in pregnant women who were offered a single dose of rubella vaccine at different ages of their lives. MethodsA total 15,067 rubella IgG antibody test results for Taiwanese pregnant women who received routine prenatal checkup at Fooyin University Hospital from 1999 to 2014 were analyzed in this study. The women were divided into five birth cohorts in order to compare their rubella seronegativities and antibody titers according to the different period of rubella vaccination policy in Taiwan. ResultsThe total rubella seronegativity rate was 11.2% (95% CI: 10.7–11.7%) and the mean rubella antibody titers was 51.0IU/mL (SD=54.7IU/mL). The junior school cohort has the lowest rubella seronegativity of 7.6% (95% CI: 6.9–8.2%). The seronegativities were significantly high in the preschool cohort and in the 15-month-old cohort, 14.9% (95% CI: 13.2–16.6%) and 14.8% (95% CI: 11.5–18.1%), respectively. The OR values were 2.1 (95% CI: 1.8–2.5, p<0.001) in the preschool cohort and 2.2 (95% CI: 1.6–2.8, p<0.001) in the 15-month-old cohort, respectively, against the junior school cohort. Women in the 15-month-old cohort have lowest average rubella IgG titer, 25.4IU/mL. ConclusionThe total rubella seronegativity rate was 11.2% in all native pregnant women. Women who received one dose rubella vaccine at preschool and 15-month-old have highest seronegativities. The 15-month-old cohort has the lowest average rubella IgG titer. We recommend a revised catch-up immunization policy to women who received one dose rubella vaccine at a younger age.

Economic impact of switching rubella IgG methodologies to the prenatal public health program in Alberta

BackgroundDespite widespread use of a universal rubella standard, variability in rubella antibody titre can be observed between assays, particularly at the low end of the linear range. ObjectivesHere, we investigate the impact of a methodology change for rubella IgG from the Abbott AXSYM to the Abbott Architect in a comprehensive prenatal screening program in the Canadian province of Alberta. Study design51,815 specimens (21,399 tested by AxSYM and 30,416 tested by Architect) submitted for routine prenatal screening between January 2006 and December 2012 from women who lived in Alberta after the universal childhood immunization programme for rubella was implemented, and whose immunization records were available, were included in the study. ResultsPrenatal samples tested by AxSYM for rubella IgG were approximately 30% higher than those reported by Architect. Among individuals who had tests across multiple pregnancies, the change in test platform led to an additional 7% of women who initially tested positive, becoming non-positive (i.e. negative or indeterminate) in their subsequent tests. The tendency of the Architect IgG assay to report lower quantitative values was demonstrated across all birth cohorts and vaccination status, and resulted in an additional 2800 women requiring vaccination between 2010 and 2012 with an estimated cost of $38,500. ConclusionThe change in rubella IgG screening assay resulted in a significant increase in the number of women who required post partum vaccination and Public Health follow-up.

Persistence and Half-lives of Anti-measles and Anti-rubella Antibodies in Japanese Hospital Workers: A Longitudinal Study.

Objective Antibody testing for endemic viruses in healthcare workers is used as an index of immunoprotection in Japan. However, it remains unclear how these antibody titers chronologically change and how they should be interpreted. Methods We retrospectively collected two sets of antibody titers to measles and rubella, measured in 2013 and within the preceding 5 years, in adult hospital workers by an enzyme-linked immunoassay and calculated in international units. Subjects infected with, or vaccinated against, these viruses over this period were eliminated. Seropositivities and geometric mean titers were analyzed. Decay rates and half-lives of antibodies were calculated using a mixed-effect model according to the subjects' ages and antibody titers. Results We analyzed 469 subjects for measles and 439 for rubella. Comparison with previous data revealed a mean measurement interval of 1,026 days between the previous and present tests, with seropositivity rates of 98.0% (previous) vs. 99.3% (present) for measles; 974 days and 90.7% vs. 94.9%, respectively, for rubella. For measles and rubella, 97.4% and 86.1%, respectively, of previously seropositive subjects remained positive in the present test. The geometric mean titers in the present and previous tests were 924.3 IU/mL and 853.2 IU/mL (measles) and 46.23 IU/mL and 40.78 IU/mL (rubella), respectively. In the mixed-effect model, measles and rubella antibody titers showed an increasing trend with age. Conclusion Seropositivities against measles and rubella can remain high for more than 5 years. Among adult hospital workers in Japan, the antibody titers against measles and rubella have a sufficient lifetime persistence.

妊婦の風疹抗体価に基づく風疹ワクチン接種推奨の必要性に関する検討

We investigated rubella antibody titer during pregnancy, delivery history, and labor age in 728 pregnant women between January 2013 and December 2013 in Kobe City Medical Center General Hospital. Among 728 pregnant women, women with high antibody titer numbered 534, and women with low antibody titer numbered 194. In total, the rubella antibody prevalence rate in this study was 73.4% and the percentage of pregnant women with low antibody titer was 26.6%. The rubella antibody prevalence rate of 387 primiparous and 341 multiparous women was 72.4% (280) and 74.5% (254), respectively. Their delivery histories were not related to the rubella antibody prevalence rate (P = 0.52), but pregnant women with high antibody titer were significantly older than pregnant women with low antibody titer (P = 0.0002). We started to recommend receiving the post-partum rubella vaccine to 157 pregnant women with low antibody titer from February 2013. One hundred and thirty-six (86.6%) pregnant women with low antibody titer received the postpartum rubella vaccine according to our recommendation. One of the effective measures to prevent future occurrences of Congenital Rubella Syndrome is to aggressively recommend rubella vaccination so that pregnant women with low antibody titer do not miss an opportunity to receive the post-partum vaccination.

Pregnancy outcomes of women with failure to retain rubella immunity

Objective: We sought to explore the clinical variables associated with the loss of rubella immunity during pregnancy and to determine if these changes are linked to obstetrical complications.Methods: This is a case-control study in which women were identified whose rubella antibody titers were equivocal or non-immune and compared to those who had retained immunity. Two hundred and eighty-five cases were identified and compared to the same number of controls using Student’s t test, Mann–Whitney U-test or Fisher’s exact test. Univariate and multivariate logistic regressions were employed.Results: Subjects with diminished immunity were more likely to have public insurance and higher gravidity with a trend toward increased tobacco use. Diminished rubella immunity was not associated with adverse obstetrical outcomes, including preterm birth and pre-eclampsia and is likely not a risk factor for these pregnancy outcomes.Conclusion: While no adverse pregnancy outcomes were associated with a loss of rubella immunity, women with greater number of pregnancies appear to lose their immunity to rubella. This relationship needs to be explored further and if proven, revaccination prior to pregnancy may need to be addressed.

Rubella Immunity among Pregnant Women in Jeddah, Western Region of Saudi Arabia.

To determine the presence of rubella immunity among pregnant women attending their first prenatal visit in Jeddah, Saudi Arabia, a retrospective, descriptive, cross-sectional, hospital-based study (prevalence study) was undertaken. A total of 10276 women attending prenatal clinics between January 1, 2008, and December 31, 2011 were included. Rubella screening tests (immunoglobulins: IgG and IgM), rubella antibody titer levels, patient age, gravidity, parity, and the number of previous abortions were analyzed. No patients tested IgM positive, and 9410 (91.6%) were immune (IgG positive); the remaining 866 (8.4%) were susceptible. There were no significant differences in gravidity, parity, or the number of previous abortions between immune and nonimmune groups. In contrast, the immunity rate decreased with increasing age, with a significant difference between the youngest age group (15–19 years) and the oldest age group (40–49 years) (P = 0.0005; odds ratio, 2.86; 95% confidence interval, 1.7–4.7). Rubella immunity among pregnant women was high (91.6%) but decreased significantly with increasing age. A possible explanation for this is the change in the rubella vaccination policy in Saudi Arabia in 2002, from 1 dose to 2 doses. In addition, antibody levels begin to decline after vaccination and natural infection.

Susceptibility to cytomegalovirus, parvovirus B19 and age‐dependent differences in levels of rubella antibodies among pregnant women

Infections caused by cytomegalovirus (CMV), parvovirus B19 (B19), and rubella can lead to serious complications in pregnant women. The aim of this study was to determine the susceptibility to CMV, B19, and rubella antibodies in pregnant women in Norway. Consecutive sera samples were collected from pregnant women in two different regions in Norway. Sera were collected from age groups; ≤19, 20-24, 25-29, 30-34, 35-39, and ≥40 years old. Of the 2,000 pregnant women tested, anti-CMV IgG was positive in 62.8% anti-parvovirus B19 IgG in 59.7% and anti-rubella IgG in 94.4%. CMV IgG susceptibility has decreased in pregnant women less than 30 years of age, from 60% in a study conducted in 1973-1974 to 37.2% in present study. There was a significant difference in CMV IgG seropositivity rate between the two regions (58.6% and 67.1%). Serum levels of rubella IgG was lowest in age group 25-29 years with a positivity rate of 91.0%. Women born before vaccination with two doses of MMR started, had both a higher positivity rate and significantly higher levels of rubella antibody titre, 96.1% and 82.2 IU/ml compared to those born after 92.9% and 41.7 IU/ml. Significantly lower anti-rubella IgG titre found in the youngest age groups highlights the need for continued antenatal screening. A considerable increase in anti-CMV-IgG seropositivity rate was observed and might be associated with higher rate of breastfeeding and a higher percentage attending day-care centres.

Changes in the prevalence of the measles, rubella, varicella-zoster, and mumps virus antibody titers in Japanese pregnant women

In the present study, immunity against infectious diseases, which are capable of influencing both the mother and fetus during pregnancy and the infant in the postnatal period, were assessed in pregnant women to elucidate the necessity of vaccination during the childbearing age. It was determined that there was a trend of increases in the proportion of patients that had low antibody titers observed at a young age. Overall, after adjusting for age, low antibody titers of measles (≤4 via the neutralization test [NT]), rubella (≤16 via the hemagglutination inhibition [HI]), and varicella and mumps (plus minus or negative on the enzyme-linked immunosorbent assay [EIA]) indicated that the rates of necessity for vaccination against measles, rubella, varicella, and mumps were 27.6%, 16.1%, 3.9%, and 23.8%, respectively. In Japan, acquired immunity for measles, rubella, and mumps was dependent on vaccination, whereas acquired immunity for varicella was dependent on natural infection. We recommend that women be vaccinated after delivery, as these vaccines are live, and thereby, are contraindicated during pregnancy.

Rubella seroepidemiology and estimations of the catch-up immunisation rate and persistence of antibody titers in pregnant women in Taiwan

To examine rubella seroepidemiology, and estimate rates of catch-up immunisation and persistence of antibody titers in pregnant women in Taiwan after mass immunisation. A retrospective study. Two medical centres and four regional hospitals specialising in obstetric care. A total of 43,640 prenatal rubella test results for pregnant women from 2001 to 2008. Rubella immunoglobulin G (IgG) antibody assay. Seronegativity, rate of catch-up immunization, and antibody decline. The seronegativity was 10.9% in all pregnant women. Immigrant women had higher seronegativity than indigenous women (OR 2.86; 95% CI 2.65, 3.01). Indigenous women born prior to implementation of the vaccination programmes were more susceptible (20.1%) to rubella infection than were women born thereafter (6.7%). Rates of seropositive conversion were low in both Taiwanese-born and foreign-born women (11.5 and 30.7%, respectively). The rubella antibody titers for vaccinated Taiwanese women in the 1971-1976 and after-1976 birth cohorts declined by 0.6 and 2.3% per year, respectively. This study demonstrates high seronegativity of older indigenous and immigrant women, a low catch-up immunisation rate, and the persistence of rubella antibodies in Taiwan after mass vaccination. Our study suggests that a single dose of rubella vaccine in teenagers effectively increased rubella seropositivity during their childbearing years. This finding is useful for countries that lack the resources necessary for a two-dose regimen. We recommend free rubella antibody tests to women of childbearing age and free vaccination as required. All postpartum women testing negative for rubella antibodies should be vaccinated before they leave hospital.

MR ワクチン第 3 期および第 4 期接種の免疫原性

A two-phase combined measles-rubella vaccine (MR) immunization schedule was introduced for age 1 and prior to primary school entry in Japan in April 2006. Further immunization was also introduced for 13 (Phase 3) and 18-year-old (Phase 4) cohorts for the 5-year period from April 2008 to March 2013. We surveyed Phases 3 and 4 MR immunization immunogenicity and safety. From August 2007 to December 2009, we conducted 3 Phase 3 and 15 Phase 4 immunizations. We then took paired serum samples (pre- and 4-6 weeks post-immunization), and measured measles antibody titers using hemagglutination inhibition (HI) and neutralizing test (NT), and rubella antibody titers using HI. Pre-positive measles HI antibody titer (> or = 8) was 72% (13/18) and pre-positive measles NT antibody titer (> or = 2) was 100% (18/18). Post-positive measles HI and NT antibody titers were 94% (17/18) and 100% (18/18). Mean post-immunization measles HI and NT antibody titers were significantly higher than pre-titers, with four-fold or greater increases seen in 9 (50%) and 6 (33%) subjects. Pre-positive rubella HI antibody titer (> or = 8) was 94% (17/18), and post-positive rubella HI antibody titer 100% (18/18). Mean post-immunization rubella HI antibody titer was significantly higher than pre-titer, with four-fold or greater increases seen in 8 subjects (44%). Paired HI antibody titers were measured in pre- and post-Phase 1 immunization for measles in 3 subjects and for rubella in 2 subjects. Those with post-Phase 1 measles HI antibody titers of 32, 64, and 128 yielded titers of 16, 8, and < 8 pre-Phase 3 or Phase 4 immunization, showing antibody reduction or seronegative conversion. Those with post-Phase 1 rubella HI antibody titers of 128 and 256 yielded titers of 64 and 32 in pre-Phase 4 immunization, showing antibody reduction. Seroconversion or four-fold or greater increases in titer were seen post-immunization in 60% (3/5) of these subjects. A clinical reaction survey of all subjects 4 weeks post-immunization, showed only 1 case of mild fever and no local or systemic adverse reactions such as generalized urticaria or anaphylaxis. In conclusion, Phases 3 and 4 MR immunogenicity was satisfactory.

Measurement of serum rubella antibody titers in Korean children, female adolescents, and pregnant women.

IgG antibody titers to rubella virus in serum of 322 nuchal cord blood, 1,473 children, and 1,103 reproductive and pregnant women were detected in Soonchunhyang University Hospital in Korea. Positive rate of IgG antibody to rubella virus was 86.3% (278/322) in nuchal cord blood, 68.0% (991/1,458) in children. The IgG antibody from the mother disappeared between the 7th to 11th month after birth, and then the positive rate increased as age increased. In the reproductive age group including pregnant women, positive rate of IgG antibody was 81.8% (894/1,103). Therefore, it was known that there was a possibility that 18.9% of this group would be attacked with rubella in Korea.