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.     

Surveillance of congenital rubella syndrome in Japan, 1978-2002: effect of revision of the immunization law

Infection of rubella virus at the early stages of pregnancy in women who are not immune to rubella often induces congenital anomalies in infants, namely congenital rubella syndrome (CRS). This paper is the first comprehensive report of CRS cases in Japan, compiled from a questionnaire to major hospitals, reports to journals and academic meetings, and cases for virus/virus genome verification submitted to the National Institute of Infectious Diseases. CRS incidence in Japan was determined to be 0.2-8.1 cases/100,000 live births per year in epidemic years and 0.1-0.7 in non-epidemic years, respectively. In the last 4 years, the number of CRS cases remarkably decreased to one-three cases per year. This decrease is thought to be because the immunization law was revised in 1994 for changing the focus of rubella immunization from junior high school girls to infants of both sexes.     

The epidemiology of rubella and congenital rubella in Australia, 1992 to 1997.

Selective rubella vaccination of schoolgirls commenced in 1971 and was followed by a significant reduction in congenital rubella. Infant vaccination with MMR was introduced in 1989 to interrupt circulation of the virus in young children, and in 1994/95 the adolescent school based rubella vaccination program was changed to MMR for both boys and girls. This report reviews the epidemiology of rubella and congenital rubella between 1992 and 1997 using reports to the National Notifiable Diseases Surveillance System (NNDSS) and the Australian Paediatric Surveillance Unit (APSU). Notification rates for rubella exceeded 20 per 100,000 in 1992, 1993 and 1995 and declined to 7.2 per 100,000 in 1997. Sixty-one per cent of notifications occurred between September and December and 68% occurred in males. The incidence rate in males aged 15-22 years peaked at 152.6 per 100,000 in 1995 reflecting the lack of immunisation in this cohort. From 1993 to 1997, 19 children were reported with congenital rubella syndrome, representing 1 in 67,000 live births. Of these, 17 had multiple defects (4 died) and 2 had deafness only. There were also 5 infants with congenital rubella infection but no defects. Australia's rate of congenital rubella syndrome exceeded that of the United Kingdom and the United States of America but this may be partly attributable to differences in reporting practices. The impact of changing the second dose of MMR vaccine to 4 years of age in 1998 will require careful monitoring.     

上海市1990-2006年风疹流行病学特征分析

目的了解1990—2006年上海市风疹流行病学特征。方法用描述流行病学方法分析1990—2006年上海市传染病报告疫情数据库，数据采用Excel整理与分析。结果1990—2006年上海市风疹报告发病率为0．15110万～451．57／10万；1993年上海市发生风疹大流行，是风疹发病最高的年份，共报告风疹病例58104例，1998年是风疹发病的最低年份，共报告19例；1990—1994年（疫苗使用前）年平均报告发病率为93．00/10万，在疫苗使用前，风疹发病有明显的季节性特征，每年发病高峰集中在3—6月；风疹病例主要集中在儿童和青少年人群，即以5～9岁和10～14岁年龄组为主。1995年开始在上海市大规模使用风疹联合疫苗（MMR）后，全市MMR接种率达85％以上。风疹发病率呈逐渐下降趋势，每年报告风疹发病数除1995年外均〈100例，风疹的发病得到有效控制。但疫苗使用后，风疹发病的年龄构成有所改变，0～4岁发病年龄构成增加，占总发病数的21．00％，且发病年龄有逐年后移趋势，20岁以上年龄组发病占总发病数的31．62％，1995—2006年25～29岁年龄组和30～34岁年龄组风疹发病率均高于疫苗使用前（除1993年）相同年龄组的发病率。结论上海市风疹发病年龄后移。     

Rubella epidemic in the Netherlands, 2004/'05: awareness of congenital rubella syndrome required

Rubella is a public health problem due to the teratogenic effects associated with primary rubella infection during pregnancy (congenital rubella syndrome). Following universal rubella vaccination of infants in the Netherlands, the incidence of rubella has declined dramatically. However, since September 2004, an outbreak has occurred among unvaccinated individuals, most of whom declined vaccination based on religious beliefs. In the period 1 September 2004-22 March 2005, 166 cases of rubella were reported, including 12 pregnant women. Monitoring for signs that the epidemic has spread to other populations in the Netherlands is important because this might indicate the need for additional interventions. Awareness among health-care workers of the possible occurrence of congenital rubella syndrome should be raised. The clinical manifestations of congenital rubella syndrome are diverse, can be transient or permanent, and may not present until adolescence or adulthood. All cases of laboratory-confirmed rubella infection and congenital rubella syndrome should be reported to municipal health authorities. There is a possibility that this outbreak will spread abroad. The WHO aims to reduce the incidence of congenital rubella syndrome to < 1/100,000 live births. Health-care workers in the Netherlands should be extra alert to detect and notify rubella in a timely manner.     

Unseen blindness, unheard deafness, and unrecorded death and disability: congenital rubella in Kumasi, Ghana

OBJECTIVES: Although rubella serosusceptibility among women of reproductive age in West Africa ranges from 10% to 30%, congenital rubella syndrome has not been reported. In Ghana, rubella immunization and serologic testing are unavailable. Our objectives were to identify congenital rubella syndrome cases, ascertain rubella antibody seroprevalence during pregnancy, and recommend strategies for congenital rubella syndrome surveillance. METHODS: Congenital rubella syndrome cases were identified through prospective surveillance and retrospective surveys of hospital records. A rubella serosurvey of pregnant urban and rural women was performed. RESULTS: Eighteen infants born within a 5-month period met the congenital rubella syndrome case definitions, coinciding with a 9-fold increase in presentation of infantile congenital cataract. The congenital rubella syndrome rate for this otherwise unrecorded rubella epidemic was conservatively estimated to be 0.8 per 1000 live births. A postepidemic rubella immunity rate of 92.6% was documented among 405 pregnant women; susceptibility was significantly associated with younger age (P = .000) and ethnicity (northern tribes, P = .024). CONCLUSIONS: Congenital rubella syndrome occurs in Ghana but is not reported. Information about congenital rubella syndrome and rubella in sub-Saharan Africa is needed to evaluate inclusion of rubella vaccine in proposed measles control campaigns.     

Evaluation of the measles,mumps and rubella immunisation programme in Spain by using a sero-epidemiological survey

In Spain, measles, mumps and rubella vaccination was introduced in 1981, with one dose at the age of 15 months and another at the age of 11 years being administered since 1995. Reported disease incidence was less than one case per 100,000 people for measles and rubella, and 23 cases per 100,000 people for mumps. A seroepidemiological survey was undertaken to estimate the frequency of susceptible individuals by age and environment; and vaccination coverage and efficacy of the vaccines administered. A population-based cross-sectional study was then conducted, covering the population aged 2–39 years, residing in Spain (excluding Catalonia). The sample was stratified by age and rural/urban environment and informed consent obtained to take blood specimens from subjects attending blood-extraction centres. The final sample totalled 3932 persons. IgG antibodies were detected by an enzyme-linked immunosorbent assay. Estimated vaccination coverage was 96% for children aged 2–5 years; vaccine efficacies were 96.7% for measles, 97.2% for rubella and 79.3% for mumps. Immunity was the lowest in the 6–9 year age group for measles (90.8%) and in males aged between 15 and 24 years for rubella (86 and 89.8%, respectively). In the case of mumps, this proved the lowest in the 2–5 year age group (76.7%) and in those autonomous regions in which only the Rubini strain had been administered. The incidence of measles has enabled the National Measles Elimination Plan to be implemented by which the elimination of congenital rubella syndrome could now be initiated. A possible explanation for the higher susceptibility observed for mumps might lie in the Rubini strain's low efficacy.     

Rubella in Poland in 2002

In Poland, 40,518 cases of rubella were registered in 2002 (incidence 106 per 100,000 population), including 2 cases of congenital rubella syndrome (incidence 0.57 per 100,000 live births). A 52% decrease in incidence was noted with respect to the epidemic year 2001. Across the voivodeships the incidence ranged from 227.7 per 100,000 in wielkopolskie to 21.4 per 100,000 in warminsko-mazurskie. As in 2001 urban areas registered slightly lower incidence than the rural areas (104.2 and 108.9 respectively). The incidence in men (120.2) was 24% higher than in women (91.9) and this difference appears to increase with routine vaccination of 13-year old girls. The highest incidence was observed in children aged 7 (1,023.2 per 100,000), 8 (930.7) and 9 years (859.6). Approximately 0.4% of cases required hospital admission. No rubella deaths were registered.     

Rubella in Poland in 2003

In Poland, 10,588 cases of rubella were registered in 2003 (incidence 27.7 per 100,000 population). No cases of congenital rubella syndrome were reported. A 74% decrease in incidence was noted, compared to 2002. Across voivodeships, the incidence ranged from 113.1 per 100,000 in warmińsko-mazurskie to 6.2 per 100,000 in lódzkie. As in 2002 rubella incidence among residents of urban areas was lower, compared to residents of rural areas (26.4 and 29.8, respectively). The incidence in men (32.3) was 38% higher than in women (23.4) and this difference appears to systematically increase with routine vaccination of 13-year old girls. The highest incidence was observed in children aged 7 (242.0 per 100,000) and 8 years (209.3). Approximately 0.5% of cases required hospital admission. No rubella deaths were registered.     

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.     

Incidence of congenital rubella syndrome in 19 regions of Europe in 1980–1986

Twenty-five cases of congenital rubella syndrome were recorded in 1,458,126 live births in 19 EUROCAT birth defects registries from 1980 to 1986. During the study period, the incidence declined steadily from 3.50 to 0.41 per 100,000 births. Rubella infection occurred in 12 multiparous women indicating failure in immunization programme.Corresponding author.     

Modelling the incidence of congenital rubella syndrome in developing countries

BACKGROUND: As of 1997, less than one-third of developing countries included rubella vaccine in their national immunization programme. In countries that have achieved high coverage of measles vaccine, an ideal opportunity exists to include control of rubella and congenital rubella syndrome (CRS) in enhanced measles control activities. Data on the burden of congenital rubella syndrome are important to guide rubella vaccination policies. METHODS: We reviewed the literature to identify studies of rubella antibody prevalence in developing countries that were conducted on populations with no major selection bias, prior to wide-scale rubella vaccination in the country. We used a simple catalytic model to describe the age-specific prevalence of susceptibility to rubella virus infection in given populations. Estimates of the incidence of infection among pregnant women were calculated using expressions for the average prevalence of susceptibility to infection and the incidence of infection during gestation. To estimate the number of cases of CRS, we assumed an overall risk of 65% after infection in the first 16 weeks of pregnancy and zero risk thereafter. These estimates were derived for each country for which data were available, then for each World Health Organization region, excluding Europe. RESULTS: The estimated mean incidence of CRS per 100,000 live births was lowest in the Eastern Mediterranean region (77.4, range 0-212) and highest in the Americas (175, range 0-598). The mean of the estimates of the total number of cases of CRS in developing countries in 1996 was approximately 110,000. The range was, however, very wide, from as few as 14,000 to as many as 308,000 cases. CONCLUSIONS: Congenital rubella syndrome is an under-recognized public health problem in many developing countries. There is an urgent need for collection of appropriate data to estimate the cost-effectiveness of a potential global rubella control programme.     

Congenital rubella syndrome in Haiti (Short communication).

OBJECTIVE: To determine if there is an unrecognized problem of congenital rubella syndrome (CRS) in Haiti, a country without a national rubella immunization program. METHODS: During March 2001 and June 2001, screening physicals were conducted on approximately 80 orphans at three orphanages in Haiti that accept disabled children. Children were classified as probable CRS cases based on established clinical criteria. Photo documentation of findings was obtained whenever possible. RESULTS: Six children met the criteria for probable CRS. Using data from surrounding Caribbean countries and from the United States of America prior to rubella immunization, we estimated that there are between 163 and 440 new cases of CRS per year in Haiti. CONCLUSIONS: CRS exists in Haiti, but its presence is generally unrecognized. A national rubella immunization policy should be considered.     

The first newborn with congenital rubella syndrome during the rubella epidemic in The Netherlands in 2004/'05

A newborn male was diagnosed with congenital rubella syndrome. His 31-year-old mother had had erythematous exanthema during a period of amenorrhea lasting 7 weeks; she was not vaccinated and had never had a rubella infection. The infection was confirmed serologically. The mother gave birth to an icteric, microcephalic, dysmature neonate with hepatosplenomegaly and exanthema with multiple, small purple-red spots. Ultrasound cardiography revealed a persistently open arterial duct and a small defect of the ventricular septum. Radiological evaluation of the long bones showed the characteristic longitudinal lucent strands ('celery stalk appearance'). Ultrasound of the cerebrum showed diffuse widespread calcifications in the white matter and basal ganglia, striatal vasculopathy and diffuse parenchymal disorders. Psychomotor development was impaired. The patient was completely deaf in the left ear and had severely poor hearing in the right ear. After the introduction of the rubella vaccine in the Netherlands in 1974 a substantial decrease was seen in the incidence of rubella infections as well as congenital rubella syndrome. An epidemic of rubella infections has been present within the non-vaccinated population since September 2004. Recognition of the clinical symptoms and confirmation of the clinical suspicion with proper viral diagnostic methods are needed to control the current epidemic and to prevent secundary spread. Infants born with congenital rubella syndrome remain infectious to non-vaccinated individuals for a prolonged period of time; the virus is excreted in the urine and faeces. Long-term medical follow-up is necessary because the congenital rubella infection can cause abnormalities after the neonatal period.     

Brief report: Imported case of congenital rubella syndrome--New Hampshire, 2005

In 2004, an independent panel convened by CDC declared rubella no longer endemic in the United States. Nine cases of rubella were reported in 2004, and four cases of congenital rubella syndrome (CRS) were reported during 2001-2004. However, worldwide, an estimated 100,000 infants are born with CRS annually. This report describes a case of imported CRS diagnosed in an infant girl aged 10 weeks born in New Hampshire to Liberian refugee parents. To prevent transmission of rubella, clinicians should consider a diagnosis of CRS in infants with compatible clinical signs, particularly those born to mothers who recently immigrated from countries without rubella control programs, and rubella vaccine should be administered to susceptible persons.     

Congenital rubella syndrome in the United States, 1970-1985. On the verge of elimination

The National Congenital Rubella Syndrome Registry, a passive surveillance system, and the Birth Defects Monitoring Program, a newborn hospital discharge data set, are used to monitor the incidence of congenital rubella syndrome in the United States. Reports to the registry contain clinical and laboratory data which allow cases to be classified into six categories according to the likelihood of having congenital rubella syndrome. The monitoring program records newborn discharge diagnoses, without detailed information, of a nonrandom sample of about one fourth of the births in the United States annually. To evaluate the two systems and to estimate the actual incidence of congenital rubella syndrome, the authors collected hospital discharge summaries on all cases as reported by the monitoring program from 1970-1985 and classified them by the registry criteria. Of the 392 cases reported to the monitoring program during 1970-1985, 24% (n = 93) could be classified as confirmed or compatible compared with 79% (n = 415) of the 526 cases reported to the registry (rate ratio = 3.3; 95% confidence interval (CI) 2.9-3.8). Diagnosis of congenital rubella syndrome was made during the neonatal period for 68% (263 of 389) registry cases for whom such data were available. When the Lincoln-Peterson capture-recapture method of estimating population size for independent surveillance systems was used, an estimated 1,064 confirmed and compatible cases (95% CI 668-1,460) diagnosed during the neonatal period occurred during 1970-1979, for an average of 106 cases per year. During 1980-1985, an estimate of 122 neonatal confirmed and compatible cases (95% CI 8-236) occurred, for an average of 20 cases per year. A downward secular trend in the incidence of congenital rubella syndrome beginning in 1980 was observed. The registry detected 22% of all neonatal confirmed and compatible cases, the monitoring program detected 8%, and the two systems combined detected a total of 28%. The results indicate that congenital rubella syndrome may be on the verge of elimination in the United States.     

A model-based evaluation of the national immunization programme against rubella infection and congenital rubella syndrome in The Netherlands

In order to improve the prevention of cases of congenital rubella syndrome in The Netherlands, in 1987 the selective vaccination strategy against rubella infection in girls was replaced by mass vaccination. This decision was supported by mathematical model analyses carried out by Van Druten and De Boo. In order to compare the predicted impact of the rubella vaccination programme with the current available data in more detail, a similar model was built. Although the model predicts elimination of the rubella virus, data show that virus circulation is still present at a higher level than expected by the model. Simulation studies indicate that import of infection and a lower vaccine effectiveness, related to possible asymptomatic reinfection of vaccinated people, could be sources contributing to the present virus circulation. Even though the number of infections is much higher than the number of reported cases of disease, limited serosurveillance data and case notification data show that females of childbearing age are well protected by immunization.     

Elimination of rubella and congenital rubella syndrome--United States, 1969-2004

In October 2004, CDC convened an independent panel of internationally recognized authorities on public health, infectious disease, and immunization to assess progress toward elimination of rubella and congenital rubella syndrome (CRS) in the United States, a national health objective for 2010. Since rubella vaccine licensure in 1969, substantial declines in rubella and CRS have occurred, and the absence of endemic transmission in the United States is supported by recent data: 1) fewer than 25 reported rubella cases each year since 2001, 2) at least 95% vaccination coverage among school-aged children, 3) estimated 91% population immunity, 4) adequate surveillance to detect rubella outbreaks, and 5) a pattern of virus genotypes consistent with virus originating in other parts of the world. Given the available data, panel members concluded unanimously that rubella is no longer endemic in the United States. This report summarizes the history and accomplishments of the rubella vaccination program in the United States and the Western Hemisphere and the challenges posed by rubella for the future.     

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.     

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。