Surveillance of congenital rubella syndrome (CRS) in tertiary care hospitals in Hanoi,Vietnam during a rubella epidemic

ObjectiveTo describe the epidemiology and clinical features of congenital rubella syndrome (CRS) in Hanoi, Vietnam.MethodsProspective surveillance of CRS between May 2011 and March 2012 in Hanoi, Vietnam. CRS burden was assessed by clinical examination and collection of serum samples from infants in neonatology, cardiology and pediatric departments of two tertiary care hospitals in Hanoi. All infants born during the study period with clinical manifestations of CRS and seropositivity (IgM) for rubella were included in this study.ResultsDuring the surveillance period 113 infants were identified with confirmed CRS (clinical features and positive rubella IgM). Their mean age at diagnosis was 38.4 days (range 1–152 days) and 61% were female. Clinical manifestations of CRS included low birth weight <2500 g (86.0%), congenital heart disease (63.7%), hearing impairment (63.7%) and ophthalmological abnormalities (46.9%). Other clinical features at birth included: thrombocytopenia (85.0%), neonatal purpura (74.3%), splenomegaly (63.7%), hepatomegaly (62.8%) and blueberry muffin rash (61.1%). Among the mothers of infants with confirmed CRS none had received a rubella vaccine in the past and 88.4% gave a history of rubella contact during the pregnancy under study. In most cases (84.1%) maternal infection occurred in the first trimester. During the surveillance period the estimated annual incidence of CRS was 1.13/1000 live births (95% CI 0.92–1.34).ConclusionsThese preliminary baseline data show a high burden of CRS in Hanoi, Vietnam and the urgent need for universal vaccination. Surveillance to determine and monitor the national burden of CRS is essential.     

Seroprevalence of rubella in the cord blood of pregnant women and congenital rubella incidence in Nha Trang,Vietnam

To investigate susceptibility to and factors associated with rubella infection among pregnant mothers and to estimate the burden of congenital rubella infection (CRI) in Vietnam where rubella-containing vaccine (RCV) is not included in the routine immunization program, we conducted a prospective cohort study in Nha Trang, Vietnam between 2009 and 2010. Rubella-specific immunoglobulin-M and immunoglobulin-G were investigated in cord blood samples by enzyme immunoassay. Corresponding clinical–epidemiological data were analyzed and the national congenital rubella syndrome (CRS) incidence was estimated using modeling. We enrolled 1988 pairs of mothers aged 17–45 years and their newborn babies. No mothers had received RCV. Multivariate analysis revealed that mothers aged 17–24 (aOR 2.5, 95% CI: 1.7–3.8) or 25–34 (1.4, 1.0–2.1) years were more likely to be susceptible than those aged 35–45 years. Overall 28.9% (574/1988, 95% CI: 26.9–30.9%) of mothers were seronegative. The CRI rate was 151 (95% CI: 0–322) per 100,000 live births. Modeling estimated that 3788 babies (95% CI: 3283–4143) were born with CRS annually in Vietnam with an overall CRS incidence of 234 (95% CI: 207–262) cases per 100,000 live births. A substantial proportion of women of childbearing age (WCBA) are at risk of rubella infection during pregnancy and this can result in a high frequency of miscarriage or burden of CRS across Vietnam. Prompt introduction of RCV into national immunization program with catch-up vaccination to children and WCBA will reduce CRI in Vietnam.     

Surveillance of congenital rubella and rubella infections in pregnancy in EU/EEA countries, 2012: Current status and future perspective to monitor elimination

IntroductionRubella elimination and congenital rubella syndrome (CRS) prevention are targets for achievement by 2015 in the WHO-EURO Region. This paper describes the existing surveillance systems for CRS and rubella in pregnancy in order to critically interpret the findings in relation to the 2012 WHO-EURO surveillance guidelines.MethodsIn 2012 we conducted a survey to collect information on surveillance of CRS and rubella in pregnancy in 29 EU/EEA countries. Questionnaires explored the characteristics of the surveillance systems, case definition, epidemiological investigation and follow-up of cases, reference laboratories and types of tests performed.ResultsTwenty-eight countries had surveillance systems for CRS, mostly nationwide, mandatory, passive and case-based; 23 collected information on the origin of the infection; 11 reported asymptomatic infections; 6 required zero-reporting. Case definitions varied among countries, although 24 used the EU definition. Laboratories reported cases in 18 countries. Twenty countries collected information on pregnancy within the rubella surveillance system and 5 had specific surveillance for rubella in pregnancy. Two countries did not monitor outcomes of suspected infections in pregnancy; infants with CRS were monitored in all the remaining countries; asymptomatic infected infants in 15; stillbirths and fetal deaths in 13; therapeutic and spontaneous abortions in 8 and 7. Twenty-seven countries had a national reference laboratory for CRS and rubella in pregnancy; genotyping was performed in 15.DiscussionThe current surveillance systems allow adequate CRS monitoring in EU. Further efforts are needed to improve their quality, including uniform case definitions, collection of information on the origin of infection, and promotion of reporting from laboratories. Follow-up of pregnant women with suspected infection should be strengthened because it is an entry point for CRS, including detection of fetal deaths, stillbirths and abortions. Laboratory capacity for confirming congenital rubella infections and infections in pregnancy is good in EU, however the use of genotyping should be encouraged.     

Estimating the burden of rubella virus infection and congenital rubella syndrome through a rubella immunity assessment among pregnant women in the Democratic Republic of the Congo: Potential impact on vaccination policy

BackgroundRubella-containing vaccines (RCV) are not yet part of the Democratic Republic of the Congo’s (DRC) vaccination program; however RCV introduction is planned before 2020. Because documentation of DRC’s historical burden of rubella virus infection and congenital rubella syndrome (CRS) has been minimal, estimates of the burden of rubella virus infection and of CRS would help inform the country’s strategy for RCV introduction.MethodsA rubella antibody seroprevalence assessment was conducted using serum collected during 2008–2009 from 1605 pregnant women aged 15–46 years attending 7 antenatal care sites in 3 of DRC’s provinces. Estimates of age- and site-specific rubella antibody seroprevalence, population, and fertility rates were used in catalytic models to estimate the incidence of CRS per 100,000 live births and the number of CRS cases born in 2013 in DRC.ResultsOverall 84% (95% CI 82, 86) of the women tested were estimated to be rubella antibody seropositive. The association between age and estimated antibody seroprevalence, adjusting for study site, was not significant (p = 0.10). Differences in overall estimated seroprevalence by study site were observed indicating variation by geographical area (p ⩽ 0.03 for all). Estimated seroprevalence was similar for women declaring residence in urban (84%) versus rural (83%) settings (p = 0.67). In 2013 for DRC nationally, the estimated incidence of CRS was 69/100,000 live births (95% CI 0, 186), corresponding to 2886 infants (95% CI 342, 6395) born with CRS.ConclusionsIn the 3 provinces, rubella virus transmission is endemic, and most viral exposure and seroconversion occurs before age 15 years. However, approximately 10–20% of the women were susceptible to rubella virus infection and thus at risk for having an infant with CRS. This analysis can guide plans for introduction of RCV in DRC. Per World Health Organization recommendations, introduction of RCV should be accompanied by a campaign targeting all children 9 months to 14 years of age as well as vaccination of women of child bearing age through routine services.     

Rubella control in Papua New Guinea: Age-specific immunity informs strategies for introduction of rubella vaccine

Aim

To determine the age specific immunity profile for rubella from three discrete study populations in Papua New Guinea, and to inform policy regarding the possible introduction of rubella vaccine.

Background

In 2005, the Western Pacific Region (WPR), of which Papua New Guinea (PNG) is a member state, declared the goal of regional measles elimination by 2012. Recently, WPR has incorporated an accelerated control goal for rubella and congenital rubella syndrome (CRS). PNG currently recommends two doses of measles vaccination at 6 and 9 months of age with a monovalent measles vaccine, which does not include rubella vaccine.

Methods

Convenience samples were collected from 1326 eligible participants in PNG and assessed for rubella immunity using the Dade Behring Enzygnost™ Anti-Rubella-Virus enzyme immunoassay. Nearly 34% were collected during an age stratified prospective survey of febrile patients in Madang Province; approximately 49% were collected from women of childbearing age in East Sepik and Milne Bay Provinces. Remaining specimens were collected from 6 to 7-month-old infants in Port Moresby prior to receiving the first dose of measles vaccine.

Findings

Of all samples tested, 65.2% (95% confidence interval (CI): 62.6–67.8) had evidence of immunity to rubella infection. Of women more than 15 years of age, 91.6% (95% CI: 89.4–93.5) were immune. The force of infection was highest between 5 and 19 years of age.

Conclusions

Although a population-based sample was not used, our multi-centre study of the population immunity profile suggests that immunity against rubella is extremely high in most women of childbearing age, but women who become pregnant at an early age may be at high risk of rubella infection during pregnancy and potential delivery of an infant with CRS. Routine measles vaccine coverage, a proxy for measles-rubella vaccine coverage, as measured in recently published studies, is well below the WHO target of 80% coverage. Introduction of a child or infant dose of rubella vaccine requires caution and further study.     

Models of strategies for control of rubella and congenital rubella syndrome—A 40 year experience from Australia

We investigated the impact of vaccination on rubella epidemiology in Australia, using a mathematical model fitted to Australian serosurvey data and incorporating pre-vaccination European estimates of rubella transmissibility. Mass infant measles–mumps–rubella (MMR) vaccination produced a 99% reduction in both rubella and congenital rubella syndrome (CRS) incidence by 2010 compared to the pre-vaccination era (1960–70). The model is consistent with reductions in CRS based on surveillance of congenital hearing impairment. Model simulations suggest that selective schoolgirl vaccination (1971–88) was associated with a 90% reduction in CRS incidence, but only a 1–4% reduction in rubella incidence. Our model predicted that these reductions in rubella were much less vulnerable to reductions in MMR vaccine coverage than for measles. In the future, a less than 15% decrease in MMR vaccine coverage is estimated to have minimal impact before 2060, but a 20% reduction may result in a 7-fold increase in rubella incidence, with the effective reproductive number R rising from 0.28 to 0.78 by 2060. The 99% reduction in both rubella and CRS incidence and low effective reproductive number (R ≤ 0.28) we documented after 2010 are consistent with Australia having achieved rubella elimination.     

2010-2014年哈尔滨市先天风疹综合征监测分析

目的 分析2010-2014年哈尔滨市先天风疹综合征（CRS）的监测结果。方法 采用描述流行病学方法,对监测的CRS病例进行分析,并对监测指标进行评价。结果 2010-2014年,哈尔滨市共报告CRS疑似病例611例,诊断为CRS的37例,发病率在6.88/10万~15.23/10万之间,年平均发病率为10.05/10万活产儿童;临床表现主要为先天性心脏病、听力损失和眼部疾病,患儿母亲均无明确风疹疫苗接种史;实验室诊断病例感染风疹病毒的时间集中在孕4~6周。结论 我市CRS发病率仍在较高水平。应继续加强疫苗接种,开展育龄期妇女血清抗体水平监测,继续开展CRS病例监测,为制定CRS防控策略提供依据。     

Surveillance for congenital rubella in Australia since 1993: Cases reported between 2004 and 2013

Objective

To describe the epidemiology of congenital rubella infections notified to the Australian Paediatric Surveillance Unit (APSU) from 2004 to 2013 and compare that with previously published APSU data for 1993–2003.

Methods

Active national surveillance for congenital rubella infection has been conducted through the APSU since 1993. Monthly reporting by child health clinicians according to pre-defined case criteria triggers requests for clinicians to provide de-identified clinical, epidemiological, and laboratory information. Data were extracted for cases reported between January 2004 and December 2013 and compared with previous years.

Results

Five cases of confirmed congenital rubella infection were identified during the reporting period. All five infants had defects consistent with congenital rubella syndrome (CRS). Four of the infants were born in Australia during the study period, and all were born to mothers born overseas. Three of the five mothers had not had rubella vaccination, and in two vaccination status was unknown, although both were from countries without routine rubella immunization programmes. Since 1993, there have been 57 notifications of congenital rubella infection to the APSU; 40 of these infants were born between January 1993 and December 2013, of whom 34 had confirmed CRS.

Conclusions

Congenital rubella infection in Australia is predominantly among children born to unimmunized immigrant mothers. Migrant women born in rubella endemic countries without routine immunization remain an important group to target for vaccination. Rubella-susceptible women, especially those in the early stages of pregnancy, should also carefully consider the risks of travelling to rubella endemic countries.     

Prevalence of antibodies against rubella virus in The Netherlands 9 years after changing from selective to mass vaccination

A two-dose mass vaccination programme with a combined vaccine against measles, mumps and rubella (MMR) was adopted in the Netherlands in 1987, replacing the selective schoolgirl vaccination strategy introduced in 1974. To obtain insight into the effect of mass vaccination and the population's immunity, the antibody levels against rubella were studied in the general Dutch population and in religious groups refusing vaccination. In the national sample, we observed a high prevalence (96.5%) for rubella antibodies in vaccinated cohorts as well as in the older unvaccinated cohorts. No indications of rapidly waning immunity after vaccination were found. There are indications of low virus circulation in the last few years. The very high seroprevalence in women at childbearing age is consistent with the few reported cases of congenital rubella syndrome (CRS) at present. However, individuals in the age group of 1-9 years who are not vaccinated for religious or other reasons have a considerably lower seroprevalence and thus there is a potential risk of a CRS outbreak in the future.     

Rubella susceptibility in pregnant women and results of a postpartum immunization strategy in Catalonia,Spain

BackgroundElimination of congenital rubella syndrome depends not only on effective childhood immunization but also on the identification and immunization of rubella susceptible women. We assessed rubella susceptibility among pregnant women and evaluated the adherence and response to postpartum immunization with measles, mumps and rubella (MMR) vaccine.MethodsCross-sectional study of women who gave birth at the Hospital Clinic de Barcelona (Spain) between January 2008 and December 2013. Antenatal serological screening for rubella was performed in all women during pregnancy. In rubella-susceptible women, two doses of MMR vaccine were recommended following birth. We evaluated rubella serological response to MMR vaccination in mothers who complied with the recommendations.ResultsA total of 22,681 pregnant women were included in the study. The mean age was 32.3 years (SD 5.6), and 73.6% were primipara. The proportion of immigrants ranged from 43.4% in 2010 to 38.5% in 2012. The proportion of women susceptible to rubella was 5.9% (1328). Susceptibility to rubella declined with increasing maternal age. Immigrant pregnant women were more susceptible to rubella (7.6%) than women born in Spain (4.6%). Multivariate analyses showed that younger age (≤19 years) aOR 1.7 (95% CI 1.1–2.5), primiparas aOR 1.3 (95% CI 1.1–1.5) and immigrant women aOR 1.6 (95% CI 1.4–1.8) were more likely to be susceptible. The second dose of MMR vaccine was received by 57.2% (718/1256) of rubella-susceptible women, with the highest proportion being immigrant women compared with women born in Spain. After vaccination, all women showed rubella immunity.ConclusionsThe higher rubella susceptibility found in the three youngest age groups and in immigrant women highlights the relevance of antenatal screening, in order to ensure identification and postpartum immunization. The postpartum immunization strategy is an opportunity to protect women of childbearing age and consequently prevent occurrence of CRS, and to increase vaccination coverage against rubella and other vaccine-preventable diseases.     

Immunogenicity,duration of protection,effectiveness and safety of rubella containing vaccines: A systematic literature review and meta-analysis

BackgroundRubella containing vaccines (RCV) prevent rubella virus infection and subsequent congenital rubella syndrome (CRS). To update the evidence on immunogenicity, duration of protection, effectiveness and safety of RCV, we conducted a systematic literature review.MethodsWe searched EMBASE and SCOPUS, using keywords for rubella vaccine in combination with immunogenicity (seroconversion and seropositivity), duration of protection, efficacy/effectiveness, and safety. Original research papers involving at least one dose of RCV (at any age), published between 1-1-2010 and 17-5-2019 were included. Where appropriate, meta-analyses were performed. Quality of included studies was assessed using GRADE methodology.ResultsWe included 36 papers (32 randomized controlled trials (RCTs) and 4 observational studies) on immunogenicity (RA27/3 strain) in children and adolescent girls, 14 papers (5 RCTs and 9 observational studies) on duration of protection, one paper on vaccine effectiveness (VE) (BRDII strain), and 74 studies on safety, including three on safety in pregnancy.Meta-analysis of immunogenicity data showed 99% seroconversion (95% CI: 98–99%) after a single dose of RCV in children, independent of co-administration with other vaccines. Seroconversion after RCV1 below 9 months of age (BRDII strain, at 8 months) was 93% (95% CI: 92–95%). For duration of protection, the included studies showed a seropositivity of 88%-100% measured 1–20 years after one or two RCV doses. The single study on VE of BRDII strain, reported 100% VE after one and two doses. Among 34,332 individuals participating in the RCTs, 140 severe adverse events (SAEs) were reported as possibly related to RCV. Among the case reports on SAEs, the association with RCV was confirmed in one report (on fulminant encephalitis). Among 3,000 pregnant women who were inadvertently vaccinated, no SAEs were reported.ConclusionsOne and two doses of RCV are highly immunogenic for a long period of time, effective in preventing rubella and CRS, and safe.     

Epidemiology of rubella and congenital rubella syndrome in Japan before 1989

Epidemiological studies of rubella and congenital rubella syndrome (CRS) in Japan have been conducted since the first nationwide rubella epidemic of 1965–1969 and subsequent epidemics of 1975–1977, 1982, 1987–1988, and 1992–1993. Rubella was non-endemic in Japan before the 1975–1977 epidemic, and endemic thereafter. Japan started a selective rubella vaccination program for junior high school girls in 1977, and universal rubella vaccination of children of both sexes in 1989. No nationwide rubella epidemics have occurred since 1994.Only three children with CRS were reported in Japan before 1964; however, many children with CRS were identified in 1965 when a rubella epidemic struck Okinawa, which has many the United States military bases. After the 1965–1969 and 1975–1977 rubella epidemics on the Japanese mainland, small numbers of children with CRS were identified (hospital survey). These findings led to the hypothesis that, compared to U.S. rubella virus strains, Japanese strains of rubella virus are less teratogenic. This hypothesis strongly affected the development of rubella vaccines in Japan. However, retrospective seroepidemiological studies attributed the CRS in many children in Okinawa to the high rate of rubella infection in pregnant women. According to the survey conducted at special schools for the deaf, 83, 232, 77, and 167 children were born with CRS on the Japanese mainland respectively after the 1965–1969, 1975–1977, 1982, and 1987–1988 nationwide rubella epidemics, suggesting that the incidence of CRS in Japan is in fact comparable to that in the U.S. and Europe.Rubella epidemics in children have been effectively prevented since 1994. However, a rubella outbreak among adult males and CRS occurred between 2012 and 2014.     

Current epidemiology of rubella and congenital rubella syndrome in Australia: progress towards elimination

This study evaluates the evidence for elimination of rubella and congenital rubella syndrome (CRS) in Australia, drawing on three national serosurveys conducted between 1996 and 2007 and supported by statutory notification and vaccine coverage data. Anti-rubella IgG seropositivity was defined as ≥ 10 IU/ml by EIA. Between 1998 and 2007, rubella notifications fell >100-fold, to an average of 2 cases per million and there were five confirmed cases of CRS, two of which were locally acquired in 2003. Weighted overall seropositivity remained constant among 1-49 year-olds (89.6% in 1999; 88.1% in 2007). Between 2002 and 2009, 95% of children received at least one dose of the measles-mumps-rubella (MMR) vaccine. All three serosurveys provided estimates for R less than 0.5, well below the epidemic threshold of 1. All available data are supportive of Australia being considered for elimination status. Further reductions in incidence of CRS will require continued attention to vaccine coverage in overseas-born women, as well as the maintenance of current high coverage level of two-dose MMR vaccination.     

深圳市宝安区育龄妇女风疹病毒免疫力状况调查

目的:通过对育龄妇女风疹抗体水平的调查,了解育龄妇女对风疹病毒免疫力状况,为科学接种疫苗提供理论根据。方法:采用定量间接ELISA方法对深圳市宝安区20～40岁1291例育龄妇女进行风疹病毒免疫力检测。结果:深圳市宝安区育龄妇女风疹病毒无保护力人群占到15.88％,明显高于80年代的调查结果;另外,20～29岁年龄组、30～40岁年龄组风疹病毒无保护力人群分别为19.4％,13.5％,两组比较统计学有显著差异(P<0.05)。结论:约有1/5生育活跃期育龄妇女对风疹病毒无保护力,孕前应加强风疹疫苗注射,以减少先天性风疹综合征的发生。     

A systematic review of rubella vaccination strategies implemented in the Americas: impact on the incidence and seroprevalence rates of rubella and congenital rubella syndrome

Objective

To evaluate the impact of rubella vaccination strategies on the rates of acquired rubella and congenital rubella syndrome in the Americas.

Methods

We conducted a systematic review of the literature (MEDLINE, PubMed, EMBASE, Cochrane Library, Artemisa Database, LILACS Database, Evidence Portal, VHL-PAHO Portal, Scielo, and Grey-Literature sources) that was published from 1969–2010. We included studies on rubella incidence and seroprevalence rates that were associated with rubella vaccination. The quality of the studies was evaluated according to international guidelines.

Results

A total of 14 studies were identified: 2 clinical trials, 2 cohort studies, 3 transversal studies, 5 ecological studies, and 2 mathematical models. Childhood vaccination reduced the incidence of rubella by 23.6% to 99.6%, increased the occurrence of epidemic cycles in Argentina and in the United States, and shifted the illness to susceptible adults. Vaccination strategies that focused on women and children in Brazil were associated with a 5.5-fold greater incidence of rubella in men leading to new outbreaks and CRS. A combined vaccination strategy with a universal approach that included routine vaccination for boys, girls, women, and men in Mexico and in Costa Rica reduced the incidence of rubella by more than 98% and led to absence of CRS since 2008. A medium and a low risk of bias were found in 3 and 4 articles, respectively.

Conclusion

The results of this review demonstrate that the combined vaccination strategy with a universal approach was the most effective strategy as evidenced by a drastic reduction in the number of cases and the interruption of endemic transmission of rubella in the Americas.     

Safety of inadvertent anthrax vaccination during pregnancy: An analysis of birth defects in the U.S. military population, 2003–2010

BackgroundAnthrax vaccine adsorbed (AVA) vaccination is compulsory for United States military servicemembers with operational indicators. As the number of female military servicemembers has increased, so has the chance of inadvertent AVA vaccination during pregnancy. Building upon past analyses assessing AVA vaccination during pregnancy and birth defects risk, this study sought to determine if inadvertent AVA vaccination during pregnancy is significantly associated with risk of birth defects after adjusting for other potential risk factors.MethodsThe study population included 126,839 liveborn infants in the Department of Defense Birth and Infant Health Registry (2003–2010). Mothers were categorized by AVA vaccination exposure timing in relation to pregnancy. Infant medical records were assessed for birth defect diagnoses within the first year of life. Multivariable logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs).ResultsInfants of first trimester AVA vaccinated mothers versus receipt at any other time point (OR, 1.10; 95% CI, 0.93–1.29) were not at higher odds of birth defects in adjusted models. Infants of mothers vaccinated prepregnancy versus postpregnancy had a 1.11 (95% CI, 1.01–1.22) higher odds of having a birth defect. Vaccination postpregnancy versus never vaccinated revealed a 10% lower odds of birth defects (OR, 0.90; 95% CI, 0.83–0.99).ConclusionsNo strong associations between inadvertent AVA vaccination during pregnancy and birth defects risk were observed. Marginal associations between prepregnancy vaccination or never vaccinated women and birth defects risk was observed when compared to postpregnancy vaccination. These findings may be due to self-selection and/or reverse causation bias when assessing comparisons with postpregnancy vaccination, and a “healthy worker” effect when assessing comparisons with women never vaccinated.     

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 51.0 IU/mL (SD = 54.7 IU/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, 25.4 IU/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.     

A resurgence of congenital rubella in Australia?

Two infants with congenital rubella defects (congenital rubella syndrome) have been reported from Queensland in 2003, after an increase in rubella in that State in 2001-2002. The national Measles Control Campaign in 1998 aimed to give measles-mumps-rubella (MMR) vaccine to all unvaccinated preschoolers and a second dose to primary schoolchildren. Following the Campaign no children with congenital rubella defects were born to Australian-born mothers during the five years 1998 to 2002, according to reports to the Australian Paediatric Surveillance Unit. However, three imported cases occurred. Broad immunisation coverage and detection and vaccination of susceptible women of child-bearing age before they become pregnant are necessary to prevent further cases.     

Rubella infection during pregnancy in the 1985–86 epidemic: Follow-up after seven years

The study covered 310 pregnant women from southern Poland who were exposed to rubella during the 1985–86 epidemic, none of whom had been vaccinated against rubella. Rubella specific antibodies were detected by hemagglutination –inhibition (HI) tests, and IgM antibodies by enzyme immunoassay (ELISA) (Organon Teknika). Clinical symptoms according to anamnesis were recorded. The consequences of serologically confirmed maternal rubella on the course of pregnancy and on fetal outcome were evaluated. IgM antibodies could be examined in only 10 newborns at delivery or in the first days of life. After seven years, follow-up studies of children born to infected mothers were done. The mental development of 14 of these children was evaluated with Terman-Merrill test. Among 310 women examined during pregnancy, rubella infection was confirmed serologically in 46 cases (14.8%). All but 3 of those had clinical symptoms. The course of pregnancy was observed in 36 of the infected mothers. Only 5 women (22.7%) who had the infection in the first trimester of pregnancy delivered a healthy child. The rate of complications in pregnancy among women infected in the second trimester was lower, and 8 (66.7%) bore healthy children. All the children born to mothers infected in the third trimester were healthy. Eight of the 10 newborns examined at delivery were IgM positive. Of 29 children congenital rubella syndrome (CRS) was confirmed in 5 cases, CRS compatible or CRS possible in 7 and 3 had congenital infection only confirmed serologically (IgM-positive) without defects or symptoms. Seventheen (58.6%) children were found healthy including the 3 who had congenital infection only. The mental development of 14 children at age 7 was assessed; 10 cases (72%) fell within rank II 130-85, and 4 (28%) were of borderline intelligence. The study indicates that congenital rubella is still a serious problem in Poland. Immunization was introduced only in 1988–89, for 13-year-old girls. Women of child- bearing age should be screened for rubella antibodies and those susceptible to rubella infection should be vaccinated.     

Inadvertent rubella vaccination of pregnant women: evaluation of possible transplacental infection with rubella vaccine

During mass campaign for measles/rubella vaccination on December 2003 in Iran, many pregnant women have vaccinated mistakenly. These women were grouped to susceptible and immune against rubella before vaccination by the status of IgG avidity response to rubella vaccine, then susceptible women were followed up to delivery time and their neonates were followed up to one year. In five neonates that were born from susceptible women, rubella-specific IgM has detected in cord blood sera, but they have not shown signs compatible to congenital rubella syndrome.