Public Health Implications of Rubella Antibody Levels in California

Rubella hemaggluttination inhibition (HI) antibody determinations were performed in 1977 on a sample of California school children and in 1977-1979 on young women who were about to be married or who were pregnant. Among the pupils, 66 per cent reported prior rubella immunization; immunization history was more common in younger pupils. Seventy-seven per cent had detectable antibody, with little trend of greater seropositivity at older ages. Over 86 per cent of those with a written record of immunization had detectable antibody. There was no consistent indication of loss of seropositivity with increasing time since immunization. Children immunized at 12-14 months of age tended to have a lower seropositivity rate than those immunized at older ages. Among young women, the prevalence of detectable antibody was 80-83 per cent. Comparison with data obtained in 1968-1969 indicates that rubella immunization has had a marked impact on antibody levels in children but less impact on levels in teenagers and adults. The pool of rubella-susceptibles entering secondary schools will probably not decrease soon, so that rubella outbreaks may continue in high school and college-age populations. Ultimately, school entry immunization requirements should drastically curtail disease activity. In the interim, programs to immunize teenagers and young adult females must be strengthened. (Am J Public Health 1982; 72:167-172.)     

山东省实施儿童风疹疫苗免疫后风疹发病年龄变化趋势的分析

目的分析山东省自1995年开始实施儿童风疹疫苗免疫后风疹发病年龄的变化趋势。方法对1999—2004年通过麻疹疫情专报系统得到的风疹疫情资料以及风疹疫苗接种情况进行分析。结果1999—2004年山东省风疹年平均报告发病率为0．59／10万，多为暴发（占总病例数的81．17％）；发病主要集中在7～15岁学龄儿童（77．77％），7岁以下发病较少（占7．93％），发病年龄中位数分别为10．37岁、11．66岁、11．41岁、12．81岁、14．28岁和13．96岁，发病高峰年龄逐年后移，成人发病有所增加；学龄前儿童风疹疫苗基础免疫估算接种率约为60％，学龄儿童约为20％。结论风疹发病年龄后移，将威胁育龄期妇女，增加发生先天性风疹综合征的危险性；应在继续做好儿童风疹免疫的同时，积极开展育龄期妇女风疹抗体筛查及疫苗接种工作。     

The immunoglobulin M response to rubella vaccine in young adult women

Rubella vaccination histories were taken from 333 young women working in the head office of a retail organization: 29% said they had had vaccine and 47% said they had not. The remainder did not know. Forty-six per cent of those less than or equal to 25 years old (who should have been offered vaccine at school), and 6% of those greater than 25 years old, said they had been vaccinated. When screened for immunity to rubella by radial haemolysis (RH) 3% had a low level of antibody (less than 15 i.u./ml) and 11% had no antibody. After immunization with Cendevax the specific rubella IgM response was measured by an IgM antibody capture radioimmunassay (MACRIA). It was only detectable in the group without RH antibody, and was present in 26/31 of them. The IgM response to Cendevax was strongest in specimens taken 20-39 days after immunization, but in 10 out of 11 cases tested was still present at around 71 days. The specific IgM responses to Cendevax were very similar to those in women given Almevax in an earlier study, when measured in parallel tests. Taking both vaccines together, specific IgM was present in 35 out of 36 vaccinees without pre-existing antibody tested between 40 and 77 days post-immunization. Detection of specific IgM by MACRIA would therefore be an effective means of determining susceptibility retrospectively in rubella vaccinees found to be pregnant.     

The immunoglobulin M response to rubella vaccine in young adult women.

Rubella vaccination histories were taken from 333 young women working in the head office of a retail organization: 29% said they had had vaccine and 47% said they had not. The remainder did not know. Forty-six per cent of those less than or equal to 25 years old (who should have been offered vaccine at school), and 6% of those greater than 25 years old, said they had been vaccinated. When screened for immunity to rubella by radial haemolysis (RH) 3% had a low level of antibody (less than 15 i.u./ml) and 11% had no antibody. After immunization with Cendevax the specific rubella IgM response was measured by an IgM antibody capture radioimmunassay (MACRIA). It was only detectable in the group without RH antibody, and was present in 26/31 of them. The IgM response to Cendevax was strongest in specimens taken 20-39 days after immunization, but in 10 out of 11 cases tested was still present at around 71 days. The specific IgM responses to Cendevax were very similar to those in women given Almevax in an earlier study, when measured in parallel tests. Taking both vaccines together, specific IgM was present in 35 out of 36 vaccinees without pre-existing antibody tested between 40 and 77 days post-immunization. Detection of specific IgM by MACRIA would therefore be an effective means of determining susceptibility retrospectively in rubella vaccinees found to be pregnant.     

2012年北京市西城区健康人群风疹抗体水平调查及疫苗免疫效果分析

目的 评估2012年北京市西城区健康人群风疹抗体水平及疫苗的免疫效果,为预防控制风疹及完善疫苗免疫策略提供科学依据。 方法 2012年随机抽取西城区10个居委会为调查点,选择在当地连续居住6个月以上的本市和外省健康人群,采集血清标本共220份,采用酶联免疫吸附试验(ELISA)测定风疹IgG抗体,同时调查免疫史、患病史及人口学特征。 结果 风疹IgG抗体阳性率为90.00%,抗体几何平均浓度(GMC)为40.78 IU/ml,不同性别、不同户籍风疹抗体阳性率和GMC比较差异无统计学意义(均P>0.05)。有免疫史人群风疹抗体阳性率和GMC均高于无免疫史人群(均P<0.001)。接种风疹疫苗5年后,抗体阳性率仍维持在较高水平。不同年龄组人群中,风疹抗体阳性率和GMC比较差异有统计学意义(P<0.05)。1.5~岁,6~岁,15~岁及35~岁组,风疹抗体阳性率在95.45%~100%之间。25~34岁年龄组风疹抗体阳性率为88.64%,低于其他年龄组(P<0.05)。风疹抗体GMC随年龄增长和免疫后时间延长而逐渐下降。 结论 风疹疫苗的免疫效果持久。2012年北京市西城区健康人群风疹抗体保持在较高水平,预测近期不会发生风疹暴发流行。应继续做好疫情监测,当出现风疹流行迹象时,建议对育龄妇女开展风疹疫苗加强免疫,预防先天性风疹综合征的发生。     

Rubella in Seattle-King County Washington.

Assessment of the results of rubella hemagglutination-inhibition tests from women of child-bearing age in Seattle-King County suggests no community susceptibility problem except among women age 19 in 1976. Within this cohort 23 per cent were susceptible, probably because these women were too young to experience a full exposure to natural rubella prior to introduction of rubella vaccine and too old to be immunized against rubella in the elementary schools in 1970. Follow-up of women under age 25 who were seronegative for rubella antibody indicated that one-third subsequently received rubella vaccine.     

Rubella susceptibility among pregnant women in North London, 1996-1999

BACKGROUND: Rubella infection and congenital rubella are currently rare in the United Kingdom, although sporadic cases occur, often associated with travel abroad. Uptake of the combined measles, mumps and rubella (MMR) vaccine has declined in recent years, and there is a danger that rubella infection could start to circulate again, with serious implications for susceptible pregnant women. This could be a particular problem in communities where there are relatively high rubella susceptibility rates because of either poor vaccine uptake over several years or the presence of significant numbers of recent immigrants from countries without routine rubella vaccination programmes. METHODS: Routinely collected data on rubella susceptibility in pregnant women in the former North West Thames region were available for 1996-1999. Associations between year of delivery, maternal age, parity and ethnic group, and rubella susceptibility were explored. RESULTS: Overall rubella susceptibility declined significantly from 2.6 per cent to 2.4 per cent between 1996 and 1999. Whereas less than 2 per cent of British-born women were susceptible, overall susceptibility for other women was about 5 per cent. African and Asian women had particularly high susceptibility rates, and patterns of susceptibility by age and parity varied across ethnic groups. CONCLUSIONS: If rubella were to re-establish itself in the United Kingdom, women who had come to Britain in later childhood or adult life would be at higher risk of acquiring infection in pregnancy than indigenous women. Appropriate local and national strategies should be devised to ensure that all such women are offered rubella vaccination at the earliest opportunity.     

2010-2013年深圳市罗湖区育龄期妇女风疹IgG抗体水平及发病情况

目的 结合罗湖区女性风疹发病情况,重点研究育龄期妇女风疹发病情况及风疹血清IgG抗体水平,为控制风疹疫情,完善风疹免疫策略,预防先天性风疹综合征( CRS) 提供科学依据。方法 在罗湖区体检中心随机抽取四家体检单位,筛选18—35岁育龄期妇女,采集血清标本共164份,用酶联免疫吸附法检查血清风疹IgG抗体,同时分析罗湖区2010-2013年女性风疹发病情况。结果应涵盖所有的结果 育龄期妇女风疹IgG抗体几何平均浓度和阳性率分别为103.1626 IU/mL 和93.3%,各年龄组统计分析 ,差异无统计学意义( χ² =2.7668,P =0．2507;F=1.00,P=0.905)全文类似描述,如此排序,且随年龄增长,风疹抗体水平有所增加;本市和外市的育龄期妇女风疹IgG 抗体阳性率间的差异无统计学意义( χ² = 0．0238,P =0．8774) ,本市和外市的育龄期妇女风疹抗体平均浓度间的差异有统计学意义(F=0.207,P=0.991) ;有接种史、无接种史和接种史不详的育龄期妇女风疹IgG抗体阳性率间的差异无统计学意义( χ² = 2．0691,P =0．3554,F=1.508,P=0.224)。2010—2013年罗湖区女性风疹发病年龄主要集中在15—35岁,占女性发病人数的74.84%,2010—2013年所占比例分别为75%、75.63%、75%、64.7%。结论 对育龄期妇女加强接种风疹疫苗( 或含有风疹疫苗的联合疫苗) ,提高育龄妇女风疹抗体水平,是控制小月龄发病和先天性风疹综合征的重要手段。     

Implications of rubella susceptibility in young adults.

Rubella history and antibody titre were determined for 457 medical, graduate, and physician assistant students. Eighteen per cent were estimated at risk for rubella. There were no male-female differences. Health-profession students did not differ in rubella immune status from the general population. History was not helpful in assessing immune status. Approximately one-half of persons with low antibody titres had considered themselves immune, while one-half with moderate to high antibody titres had considered themselves at risk. Less than one-half of students with low antibody titres available themselves of immunization which was recommended and offered. With a high percentage of adult females at risk for rubella even in a health-motivated population and with poor follow-up on recommended immunization, current immunization practices must be improved if congenital rubella syndrome is to be further reduced. Mass inoculation of school age males and prepubertal school age females without prior determination of rubella antibody titres is suggested as a cost-effective means of decreasing incidence of congenital rubella syndrome.     

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.     

2005年山东省部分孕期妇女风疹易感性调查

[目的]了解山东省孕期妇女风疹易感性水平,为调整风疹疫苗免疫策略提供依据。[方法]2005年,采集不同地区到医院准备分娩的20~40岁孕妇血清,采用间接酶联免疫吸附定量法检测风疹IgG抗体。[结果]检测标本3 788份,风疹抗体阳性(>20 IU/ml)的2 942人,阴性(<10 IU/ml)的314人,临界值(10~20 IU/ml)的532人,易感(临界值和阴性者)合计846人,易感率为22.33%。几何平均抗体含量(CMT)为34.93 IU/ml。不同地区风疹易感率和CMT的差异均有统计学意义(P<0.01);风疹易感率有随年龄增长而增高的趋势(P<0.01)。[结论]山东省近1/4的孕妇为风疹的易感者,有必要对育龄期妇女开展风疹疫苗接种。     

上海市浦东新区2012年麻疹疑似病例IgM抗体检测结果分析

目的对2012年上海市浦东新区麻疹疑似病例进行IgM抗体检测,分析麻疹流行病学特征,为进一步制订麻疹防治策略提供科学依据。方法应用酶联免疫吸附试验（ELISA）对疑似麻疹病例血清标本同时检测麻疹、风疹IgM抗体。结果 2012年该区共检测麻疹疑似病例241例。检出麻疹IgM抗体阳性111例,阳性率为46.06%;风疹IgM抗体阳性38例,阳性率为15.77%;其中有4例麻疹、风疹IgM抗体均为阳性。麻疹阳性年龄主要分布于20-30岁年龄和8个月-10岁以下年龄,其次是8个月以下婴儿。流行高峰后移至5-9月份。风疹阳性年龄20-30岁组最高,其次为30-40岁组。流行高峰在3-6月份。麻疹、风疹IgM抗体阳性率与血清采集时间有密切关系。出疹4天后采集的血清标本IgM抗体阳性率（麻疹49.75%、风疹18.27%）明显高于3天内（麻疹为29.55%、风疹为4.55%）。麻疹、风疹病例中无免疫史或免疫不详者占88.29%和92.11%。结论建议对重点人群进行麻疹强化免疫,提高免疫接种率,开展查漏补,麻疹初免年龄应适当提早。提高疑似麻疹病例的血清标本采集率。同时也需要加强风疹的监测和预防接种工作,控制风疹疫情的蔓延,并进一步加强麻疹、风疹及其他出疹性疾病的监测。     

Control of rubella and congenital rubella syndrome (CRS) in developing countries, Part 2: Vaccination against rubella.

In 1995-96 we conducted a review of rubella immunization strategies. Worldwide, 78 countries (more than one-third) reported a national policy of using rubella vaccine. This was closely related to country economic status. Based on the United Nations country classification, rubella vaccine is used in 92% of industrialized countries, 36% of those with economies-in-transition, and 28% of developing countries. Cases of congenital rubella syndrome (CRS) may be prevented as follows: by providing direct protection to women and/or schoolgirls (a selective vaccination strategy); by vaccinating boys and girls to provide indirect protection by reducing the transmission of rubella virus (a childhood vaccination strategy); or by a combination of these approaches (a combined strategy). A combined strategy was most commonly reported (60% of countries); seven countries (9%) reported a selective strategy; and 24 countries (31%) reported only childhood immunization. Experience has shown that it is essential to include vaccination of women of childbearing age in any rubella control strategy. Childhood vaccination alone may pose a risk of an increase in CRS cases. Although many countries have introduced rubella vaccine, few report any data on the impact of vaccination. Countries using rubella vaccine need to establish surveillance for rubella and CRS and monitor coverage in each of the target groups.     

Interruption of rubella virus transmission in Australia may require vaccination of adult males: evidence from a Victorian sero-survey.

Prior to the introduction of rubella vaccine to Australia in 1970 rubella was primarily a disease of primary school aged children. Vaccination programs have subsequently altered rubella age and sex susceptibility. Between July 2001 and June 2002, 85 per cent of the 32 laboratory-confirmed cases of rubella ascertained from enhanced surveillance in Victoria were males aged 20-42 years. This study aimed to determine rubella susceptibility by age group and sex in Victoria and to examine the implications of susceptibility for the interruption of circulating rubella virus. Rubella immunoglobulin G concentrations were determined for 934 residual diagnostic sera stored at the Victorian Infectious Diseases Reference Laboratory using a standard commercial enzyme immunoassay. Susceptibility was analysed by age groups defined by previous and current Australian rubella immunisation schedules. Among all subjects aged 1-55 years, males were more susceptible to rubella infection than females (10.2% vs 2.6%, p < 0.0001). Although this sex difference occurred in all age groups, it was unlikely to be explained by sampling variation in sera from subjects aged 23-44 years, for whom rubella vaccine had been recommended only for girls aged 10-14 years and rubella susceptible women post-partum. Australia's past rubella immunisation policies have resulted in a susceptible cohort of adult males. If rubella virus transmission is to be interrupted in Australia, consideration needs to be given to a rubella vaccination program targeting men aged 17-44 years. A campaign, targeting both men and women in a similar age group has recently been successful in Costa Rica.     

Rubella in the Russian Federation: epidemiological features and control measures to prevent the congenital rubella syndrome

A review of the epidemiology of clinical rubella in the Perm region of the Russian Federation from 1979-97 showed that the incidence was about 220 cases per 100,000 population. Congenital rubella syndrome (CRS) accounted for 15% of birth defects and for about 3.5 cases of CRS per 1000 live births per year. Surveys of the seroepidemiology of rubella infection revealed that the susceptibility rate among pregnant women (i.e. rubella virus antibody haemagglutination-inhibition (HAI) assay titres < 10) was 16.5%. As serum rubella antibody HAI titres > or = 10 both prevented infection in pregnant women and protected their foetuses, serological testing has been introduced into the routine antenatal services. Pre-existing rubella antibodies were found not to interfere with the immune response to vaccination, so selective immunization was provided to girls approaching puberty and to women of childbearing age. A programme of epidemiological surveillance is being developed to define tactics for the widescale introduction of rubella vaccination.     

2012年北京市平谷区健康人群风疹抗体水平监测结果

目的了解北京市平谷区健康人群风疹抗体水平,为传染病防控工作提供科学依据。方法在平谷区10个行政村（居委会）按照随机方法抽取样本,采集血标本,采用酶联免疫吸附试验（ELISA）检测风疹抗体,同时调查风疹患病史和免疫史及人口学特征。结果全区共检测251人,阳性率为82．07％,不同免疫史人群风疹抗体阳性率差异有统计学意义（x^2=33．19,P〈0．01）;0～7月龄组阳性率最低,6～9岁组阳性率最高,不同年龄组人群风疹抗体阳性率差异有统计学意义（x^2=46．18,P〈0．01）;不同性别、户籍、职业人群风疹抗体阳性率差异无统计学意义。结论提高麻风二联和麻腮风三联疫苗基础免疫,对控制风疹疫情有重要意义;另外,育龄期妇女在孕前接种风疹疫苗是有必要的。     

Policies for immunization against rubella in European countries

In 1986 a survey on immunization policies against rubella was conducted in 17 European countries. A questionnaire was sent to each Ministry of Health and selected practitioners, requesting information on official policy for vaccination against rubella, level of policy decision, immunization strategy, target groups, current recommendations for vaccination, measures taken to facilitate vaccine uptake, vaccine strains used and legislation concerning abortion.A policy for the prevention of congenital rubella is explicitly defined in 16 countries (in 12 at a national level, in 3 at a regional level and in one at both levels). In Greece only, no official policy has been defined, although the practice is to vaccinate infants over 15 months of age and girls by 9–11 years of age. There are 3 countries maintaining the selective strategy of vaccinating teenage girls, but in 8 countries this strategy changed to a mass vaccination of young infants. In 5 other countries an approach combining both mass immunization and selective vaccination is adopted. This situation of different strategies between countries in Europe could have a deleterious effect for young migrants or travelling pregnant women and could reduce the effectiveness of programmes for prevention of congenital rubella syndrome. Harmonization of immunization policies and of recommendations for vaccine administration is advisable. The mass vaccination of all young children combined with systematic revaccination either of all children or of teenage girls is probably the most effective approach for elimination of congenital rubella syndrome in Europe.Corresponding author.     

Prevalence of antibodies to measles and rubella in Sana'a, Yemen

Prevalence of antibodies to measles and rubella was tested in sera collected from 1368 subjects in urban and rural Sana'a. Overall, 11.7% had no antibodies to measles and 14.6% had no antibodies to rubella, despite the fact that measles but not rubella vaccine is included in the vaccination program in Yemen. Of 89 children <5 years of age 49 (55.1%) had no detectable antibodies to measles, demonstrating that supplementary measles immunization campaigns are required to prevent virus circulation. Assessment of measles immune status among infants in the first year of life is required to determine the optimum age for measles vaccination. Rubella vaccination should be considered with care in Yemen.     

Rubella antibody loss rates in Korean children

We followed students in eight elementary schools for rubella antibody from 1993 to 1996 (602 pairs) and 1996-9 (588 pairs) in Gyeonggi Province, Korea. We tested rubella IgG and administered rubella vaccine to the children with the titres < 10 IU/ml. The loss rates of rubella IgG during the follow-up periods were 14.3 and 15.8%, respectively. Among vaccinated groups, the loss rate was 18.8%, which was significantly higher than 13.8% of the mixture of natural and vaccine-induced immunity groups. The group that had the lower preceding antibody titre had a higher loss rate of 24.8% compared to 7.2% for the group whose titre was 40 IU/ml or above. In a multivariate analysis, age and gender were not related to antibody loss rate. Under this higher rubella antibody loss rate, in order to prevent congenital rubella syndrome, the immunization for women at childbearing age appears necessary until rubella can be eliminated or controlled.     

Response to foot-and-mouth disease vaccines in newborn calves. Influence of age, colostral antibodies and adjuvants

Oil-emulsified (OE) and aqueous (Aq) vaccines were prepared with the same batch of inactivated A24 8345 foot and mouth disease virus (FMDV). Calves born to vaccinated dams did not respond to the Aq vaccine 30 or 90 days post partum. When the OE vaccine was used on a similar group of calves, no responses were elicited up to 21 days post partum. However, calves 30 or more days old responded like adult cattle to the OE vaccine. When the OE vaccine was used in colostral antibody-free calves 3-30 days old, all animals showed good antibody responses but, in calves vaccinated 3 or 7 days post partum, antibodies were detectable only after a considerable period of time. Our results show that both passively acquired colostral antibodies and age are important in the response of very young calves to FMDV oil vaccines. From a practical point of view, in endemic areas where adult cattle are periodically vaccinated, vaccination of calves between 30 and 60 days post partum with OE vaccines would lead to high levels of herd protection.