Progress toward elimination of rubella and congenital rubella syndrome--the Americas, 2003-2008

In 2003, the Pan American Health Organization (PAHO) adopted a resolution calling for rubella and congenital rubella syndrome (CRS) elimination in the Americas by the year 2010. Elimination was defined as the interruption of endemic rubella virus transmission in all countries of North America, Central America, South America, and the Caribbean for more than 12 months and no occurrence of CRS cases attributed to endemic transmission. To accomplish this goal, PAHO developed a rubella and CRS elimination strategy (3) to 1) introduce rubella-containing vaccine (RCV) into routine vaccination programs of all countries for children aged 12 months and reach >/=95% coverage in all municipalities, 2) conduct a one-time mass campaign among adolescents and adults and periodic follow-up campaigns among children aged <5 years, and 3) integrate rubella surveillance with measles surveillance and initiate CRS surveillance. During 1998-2006, confirmed rubella cases decreased 98% (from 135,947 to 2,998) in the Americas. However, in 2007, rubella outbreaks with a total of 13,014 cases occurred in three countries (Argentina, Brazil, and Chile), primarily in males not included in previous vaccination campaigns. This report summarizes overall progress toward reaching the 2010 goal of eliminating rubella and CRS. With completion of campaigns in Argentina, Brazil, and Haiti, all countries will have implemented the recommended PAHO strategy by the end of 2008, with the expectation of reaching the 2010 rubella and CRS elimination goal.     

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.     

Global Measles and Rubella Laboratory Network, January 2004-June 2005

Measles continues to be a leading cause of childhood morbidity and mortality in developing countries and an outbreak threat in the majority of countries. In 2000, measles was considered the fifth leading cause of childhood mortality, and the World Health Organization (WHO) estimated that approximately 777,000 measles-associated deaths occurred worldwide. In 2001, WHO and the United Nations Children's Fund (UNICEF) developed a 5-year strategic plan, endorsed by the World Health Assembly in 2003, to reduce measles mortality by 50% by 2005 (relative to 1999 estimates) and to achieve and maintain interruption of indigenous measles transmission in large geographic areas with established measles elimination goals. This plan included strengthening routine vaccination coverage, providing a second opportunity for measles immunization to children, improving measles case management, and improving surveillance with laboratory confirmation of suspected measles cases. To date, four of six WHO regions have established measles elimination targets: the Americas Region (AMR) by 2000, the European Region (EUR) by 2010, the Eastern Mediterranean Region (EMR) by 2010, and the Western Pacific Region (WPR) by 2012. The remaining two WHO regions, the African (AFR) and South East Asian (SEAR) regions, are continuing work toward the measles mortality reduction goal. Likewise, to reduce the burden of disease from congenital rubella syndrome (CRS), currently estimated at 100,000 cases per year worldwide, several countries have developed or continue to develop rubella control programs, and AMR and EUR have established regional rubella elimination and CRS reduction goals, respectively. Because improved global surveillance is essential for monitoring progress toward mortality reduction and elimination of these diseases, WHO established the Measles and Rubella Laboratory Network (LabNet) in 2003 to promote case identification and confirmation. This report provides an update on the development of LabNet during January 2004-June 2005 and describes the geographic distribution of measles and rubella virus genotypes as of June 2005.     

Progress and challenges in measles and rubella elimination in the WHO European Region

IntroductionDespite availability of safe and cost-effective vaccines to prevent it, measles remains one of the significant causes of death among children under five years of age globally. The World Health Organization (WHO) European Region has seen a drastic decline in measles and rubella cases in recent years, and a few of the once common measles genotypes are no longer detected. Buoyed by this success, all Member States of the Region reconfirmed their commitment in 2010 to eliminating measles and rubella, and made this a central objective of the European Vaccine Action Plan 2015–2020 (EVAP). Nevertheless, sporadic outbreaks continue, recently affecting primarily adolescents and young adults with no vaccination or an incomplete vaccination history. The European Regional Verification Commission for Measles and Rubella Elimination was established in 2011 to evaluate the status of measles and rubella elimination based on documentation submitted annually by each country’s national verification committee.DiscussionEach country’s commitment to eliminate measles and rubella is influenced by competing health priorities, and in some cases lack of capacity and resources. All countries need to improve case-base surveillance for both measles and rubella, ensure documentation of each outbreak and strengthen the link between epidemiology and laboratory data. Achieving high coverage with measles- and rubella-containing vaccines will require a multisectoral approach to address the root causes of lower uptake in identified communities including service delivery challenges or vaccine safety concerns caused by circulating myths about vaccination.ConclusionsThe WHO European Region has made steady progress towards eliminating measles and rubella and over half of the countries interrupted endemic transmission of both diseases by 2015. The programmatic challenges in disease surveillance, vaccination service delivery and communication in the remaining endemic countries should be addressed through periodic evaluation of the strategies by all stakeholders and exploring additional opportunities to accelerate the ongoing elimination activities.     

Fortschritte bei der Eliminierung von Masern und Röteln in der Europäischen Region der WHO

Substantial progress has been made in the World Health Organization (WHO) European Region toward reaching the goal of measles and rubella elimination. We analyzed the surveillance data of 2012 on measles and rubella for agegroup, diagnosis confirmation status (clinical, laboratory-confirmed and epidemiologically linked), vaccination status, and measles-related deaths. For 2012, there were 23,871 measles cases and 29,361 rubella cases reported in the region, mostly among unvaccinated persons. Almost one in three patients with measles and one in five patients with rubellawere aged 20 years and older. In a few countries, widespread outbreaks or indigenous transmission of measles persisted in 2012. While most countries in the region have controlled rubella, a small number still reported a high incidence and several outbreaks. Therefore, more efforts are required to achieve the goal of eliminating measles and rubella in the WHO European Region by 2015, particularly in high-incidence countries. The WHO measles and rubella elimination plan stipulates that all countries should achieve and maintain the required high vaccination coverage while conducting high-quality surveillance.     

Measles and rubella eradication in the Americas

The challenge for regions embarking on measles elimination will be to maintain high population immunity with excellent vaccination coverage and high-quality surveillance. Meeting this challenge will be especially critical for dealing with importations of measles virus that will occur as long as the virus is circulating anywhere in the world. Implementation of measles elimination strategies will uncover the "hidden" disease burden of rubella and congenital rubella syndrome. As was the experience in countries of Latin America and the Caribbean (LAC), integrating the elimination of measles with the elimination of rubella will greatly enhance the capacity of countries to sustain progress in the reduction of measles mortality. Countries of LAC prioritized the routine national immunization program over short-term successes. While doing so, they have also encountered new opportunities to expand the benefits of disease control and elimination activities to other aspects of public health, most importantly towards improving health care for women and newborns and reducing inequities in health in the region's poorest communities. Implementation of similar strategies could lead to the global eradication of measles, rubella, and congenital rubella syndrome early this century, while strengthening routine immunization programs, and developing the capacity to introduce new and underutilized vaccines.     

Recommendations from an ad hoc Meeting of the WHO Measles and Rubella Laboratory Network (LabNet) on use of alternative diagnostic samples for measles and rubella surveillance

Laboratory confirmation of measles and rubella is an important component of disease surveillance in all settings. Because the use of clinical diagnosis for surveillance is unreliable, case-based laboratory confirmation of disease is critically important in settings with measles or rubella elimination goals. The World Health Organization (WHO) Measles and Rubella Laboratory Network (LabNet) was established in 2000 to provide a standardized testing and reporting structure and a comprehensive, external quality-assurance program. LabNet currently consists of 679 laboratories serving 166 countries. However, measles and rubella surveillance remains incomplete in certain areas because of difficulties with the collection and transport of serum specimens. Recently, LabNet evaluated two alternative sampling approaches to serum samples, the use of dried blood spots (DBS) and oral fluid (OF) samples. Both of these approaches have potential to be useful tools for measles and rubella control programs. In June 2007, WHO convened an ad hoc meeting in Geneva, Switzerland, to review available data and provide recommendations on use of DBS and OF samples for measles and rubella diagnostics. Attendees included LabNet staff members and scientists who had been conducting studies to evaluate use of these alternative diagnostic samples. The attendees concluded that 1) although serum-based diagnostics remain the "gold standard," the use of these two alternative sampling techniques would not adversely affect routine measles and rubella surveillance and might enhance surveillance; 2) regions in the elimination phase that already have established serum-based testing for rash illness surveillance would not likely benefit from converting to DBS or OF sampling methods, except in special circumstances; and 3) DBS or OF sampling are viable options for measles and rubella surveillance in all regions, especially where patients might resist venipuncture for blood collection, or where special challenges exist with transport or refrigeration of diagnostic samples.     

Role of the virology diagnosis laboratory in the surveillance of rubella virus Cuba 1988/2000

In Cuba, on the basis of Measles Elimination Program, the incidence of this disease decline, and was necessary to test rubella virus as a possible etiology agent that produce fever and rash illness. To reach this goal, Cuba developed rubella elimination strategies with integrated epidemiologic and laboratory surveillance. In the country, the vaccination program against rubella started in 1982 by vaccinating 12-14 years old females, with a special surveillance program with laboratory study of all suspected cases. Through 1988-2000, the Serology Diagnosis Laboratory in the Virology Branch of Pedro Kouri Institute had the responsibility to do the measles and rubella surveillance and play a key roll in the elimination strategies of these diseases. For confirmation of all suspected cases, 8566 serum samples with the suspected diagnosis of measles or rubella from different provinces in Cuba were studied in the laboratory using different techniques as haemagglutination inhibition test (HIA), ultra micro analytic assay (UMA); and in 1995 by the newly introduced IgM ELISA, which was used taken only one sample in the acute phase of the disease. These techniques allowed knowing that the annual number of reported rubella cases in the country decreased substantially after the implementation, in 1986, of the second vaccine policy, that of vaccinating women of childbearing age. However, in 1989, was detected an outbreak of rubella virus infection that had occurred in young adults male 15-19 age groups in Matanzas' province. The last three indigenous cases of this disease were confirmed by our laboratory in 1995, after national vaccine coverage over 95%.     

Global landscape of measles and rubella surveillance

BackgroundAll six World Health Organization (WHO) regions have committed to eliminate measles, and three WHO regions have committed to eliminate rubella. One of the key tenets of measles and rubella elimination is to have a strong surveillance system in place. The presence of a case-based measles and rubella surveillance system that is national, population-based, provides laboratory confirmation, and directs action, is one of the requirements for elimination-standard surveillance.MethodsIn order to understand the global landscape for measles and rubella surveillance, a questionnaire was sent to all 194 WHO member states (herein referred to as countries) requesting information on how surveillance was conducted for measles, rubella, and congenital rubella syndrome. Data were supplemented with information provided to WHO through other reporting mechanisms and by national policy documents available to the public. Frequencies and percentages were calculated.ResultsData were available to review from 164 (85%) countries, although not every country responded to every question. Case-based, population-based, national surveillance with laboratory confirmation was reported to be conducted in 136 (86%) of 158 countries for measles and 122 (77%) of 158 countries for rubella. Congenital rubella syndrome surveillance was reported to be conducted by 126 (77%) of 163 countries. Gaps were noted in the quality of measles-rubella surveillance conducted, and 26 (16%) of 158 countries reported not including all healthcare providers as mandatory reporters.ConclusionsMany countries reported having some of the essential components in place to conduct elimination-standard surveillance for measles and rubella; however, in order to achieve elimination, the quality of surveillance needs to improve to detect all cases. In those countries without these essential components of elimination-standard surveillance, the first step is to implement these components.     

Increase of vaccination coverage by mass media and individual approach: intensified measles, mumps, and rubella prevention program in Finland

In the 1970s, mass vaccination projects were started in various parts of the world against measles and congenital rubella, with eradication as the final goal. In many developing and industrial countries, including Finland, the elimination of measles failed because of low vaccination coverage. In Finland, a combined measles, mumps, and rubella (Virivac) vaccination program was started in 1982. Computerized recording of the vaccinated children was considered necessary and was integrated with the population registry to identify the hard-to-reach families. Several interventions improved compliance: a mass media campaign and notification of nonvaccinated children to local health professionals and parents. All successive campaigns increased vaccination coverage significantly, with the notification of parents about their nonvaccinated child being especially effective. A vaccination coverage of over 96% was achieved, which theoretically prevents measles, mumps, and rubella transmission.     

Measles and rubella immunity in the population of Bhutan, 2017

BackgroundIn 2017, measles elimination was verified in Bhutan, and the country appears to have sufficiently high vaccination coverage to achieve rubella elimination. However, a measles and rubella serosurvey was conducted to find if any hidden immunity gaps existed that could threaten Bhutan’s elimination status.MethodsA nationwide, three-stage, cluster seroprevalence survey was conducted among individuals aged 1–4, 5–17, and >20 years in 2017. Demographic information and children’s vaccination history were collected, and a blood specimen was drawn. Serum was tested for measles and rubella immunoglobulin G (IgG). Frequencies, weighted proportions, and prevalence ratios for measles and rubella seropositivity were calculated by demographic and vaccination history, taking into account the study design.ResultsOf the 1325 individuals tested, 1045 (81%, 95% CI 78%–85%) were measles IgG seropositive, and 1290 (97%, 95% CI 95%–99%) were rubella IgG seropositive. Rubella IgG seropositivity was high in all three age strata, but only 47% of those aged 5–17 years were measles IgG seropositive. Additionally, only 41% of those aged 5–17 years who had documented receipt of two doses of measles– or measles-rubella–containing vaccine were seropositive for measles IgG, but almost all these children were rubella IgG seropositive.ConclusionsAn unexpected measles immunity gap was identified among children 5–17 years of age. It is unclear why this immunity gap exists; however, it could have led to a large outbreak and threatened sustaining of measles elimination in Bhutan. Based on this finding, a mass vaccination campaign was conducted to close the immunity gap.     

An evaluation of measles, mumps and rubella vaccine in a population of Yorkshire infants

In October 1988 combined measles, mumps and rubella (MMR) vaccination replaced monocomponent measles as part of the routine childhood vaccination programme in the United Kingdom. Prior to this policy change a study was undertaken in 335 children aged 15 months, to evaluate the clinical reactions and immunogenicity of the new combined MMR vaccine (Trimovax, Immravax, Merieux), in comparison with an established monocomponent measles vaccine (Rouvax, Merieux). Parents were asked to select whether their child should receive MMR vaccine or measles monocomponent; over 95% chose MMR. Children who were given the MMR vaccine had seroconversion rates of 96% for measles, 97% for mumps and 100% for rubella, whilst those who received monocomponent measles vaccine had a seroconversion rate of 100%. The number of side effects reported was similar with both vaccines; all were mild and self-limiting. The results from this study confirm the efficacy and low reactogenicity of MMR vaccine and support its use as part of the routine childhood immunisation programme in the United Kingdom.     

Update: measles--United States, January-July 2008

Sporadic importations of measles into the United States have occurred since the disease was declared eliminated from the United States in 2000. During January-July 2008, 131 measles cases were reported to CDC, compared with an average of 63 cases per year during 2000-2007. This report updates an earlier report on measles in the United States during 2008 and summarizes two recent U.S outbreaks among unvaccinated school-aged children. Among those measles cases reported during the first 7 months of 2008, 76% were in persons aged <20 years, and 91% were in persons who were unvaccinated or of unknown vaccination status. Of the 131 cases, 89% were imported from or associated with importations from other countries, particularly countries in Europe, where several outbreaks are ongoing. The findings demonstrate that measles outbreaks can occur in communities with a high number of unvaccinated persons and that maintaining high overall measles, mumps, and rubella (MMR) vaccination coverage rates in the United States is needed to continue to limit the spread of measles.     

Global measles control and regional elimination, 1998-1999

In 1989, the World Health Assembly adopted the goal of reducing measles morbidity and mortality by 90% and 95%, respectively, by 1995, compared with estimates of the disease burden in the prevaccine era. In 1990, the World Summit for Children adopted a goal of vaccinating 90% of children against measles by 2000. Three regions of the World Health Organization (WHO) have targeted elimination: in 1994, the American Region (AMR) targeted elimination by 2000; in 1997, the Eastern Mediterranean Region (EMR) targeted elimination by 2010; and in 1998, the European Region (EUR) targeted elimination by 2007. This report updates progress since 1997 toward global measles control and regional elimination of measles, and includes vaccination coverage and disease surveillance data received by WHO as of August 14, 1999. Data for 1998 suggest that routine measles vaccination coverage has declined in some regions, the number of countries reporting cases and coverage to WHO has decreased, and measles continues to be an important cause of morbidity and mortality.     

Accelerated rubella control and the prevention of congenital rubella syndrome]

Congenital rubella syndrome (CRS) is associated with substantial morbidity and mortality and with high costs. Today, as a result of improved vaccination and epidemiological surveillance efforts directed at eradicating measles from the Western Hemisphere, there has been a notable increase in the ability to detect, prevent, and control rubella and CRS. The importance of these measures is undeniable, and this piece examines the components that are essential in moving ahead to reduce these major public health problems in Latin America and the Caribbean. One step in that direction would be to integrate the surveillance of measles with that of rubella and CRS.     

Seroprevalence of measles,mumps and rubella among children in American Samoa, 2011, and progress towards West Pacific Region goals of elimination

Introduction

In line with the global goals for measles elimination, countries in the West Pacific Region (WPR) have set a goal to eliminate measles by 2012. Due to its contagiousness, high population immunity is needed for achieving and documenting measles elimination. We assessed population immunity to measles, mumps and rubella among first grade children in American Samoa (AS) through a seroprevalance study.

Methods

Using commercial indirect enzyme-linked immunosorbant IgG assays (Wampole Laboratories, Cranbury, NJ) we determined IgG antibodies against the measles, mumps, and rubella (MMR) viruses in sera collected from first grade students in AS in April–May 2011. Vaccination status was retrieved from the immunization cards. Factors associated with seropositivity of measles, mumps, and rubella were analyzed separately.

Result

Among 509 first grade students, measles, mumps, and rubella seroprevalence were 92%, 90%, and 93%, respectively. The proportions of first grade students with documented one or two doses of MMR vaccine were 93% and 84%, respectively. The vaccination status of 6% of the first graders was unknown and 1% was unvaccinated. Receiving two-doses of MMR vaccines was associated with high measles and mumps seropositivity (p < 0.01).

Conclusion

The high measles seroprevalence among children shows the progress by American Samoa towards measles elimination. Achieving and maintaining high two-dose MMR vaccine coverage in all age groups will aid in attaining the measles elimination status and prevent transmission of measles from potential imported measles cases from other countries.     

Measles and rubella eradication

This article discusses concepts of eradication, some issues relating to vertical and horizontal public health programs, some current issues relating to measles and rubella, and what we need to do about them. It concludes that measles and rubella/CRS can and should be eradicated. A target date should be established in 2020 (or before). Eradication can only be accomplished in the context of strengthening ongoing immunization services and strengthening surveillance so it can guide activities. Additional resources will be required to achieve the goal.     

An epidemiological assessment towards elimination of rubella and congenital rubella syndrome in Singapore

ObjectiveIn line with regional and global goals for the elimination of rubella and congenital rubella syndrome (CRS), we reviewed the epidemiological situation in Singapore, based on surveillance reports on rubella and CRS, national immunization coverage and seroprevalence surveys. The aim of our review was to identify current gaps and steps taken to achieve the targets set by the World Health Organization (WHO) Western Pacific Regional Office (WPRO).MethodsEpidemiological data on clinical and laboratory-confirmed rubella cases, including CRS, notified to the Communicable Diseases Division, Ministry of Health, Singapore, from 2003 to 2013 were collated and analyzed. Vaccination coverage against rubella was obtained from the National Immunization Registry and School Health Services of the Health Promotion Board. The changing prevalence of rubella was determined from periodic serological surveys.FindingsThe incidence of indigenous rubella cases per million population decreased from 37.2 in 2008 to 7.6 in 2013 and there had been no indigenous case of CRS in 2012 and 2013. Therapeutic abortions performed due to rubella infections had become uncommon. The annual measles, mumps, and rubella (MMR) vaccination coverage in childhood population remained high ranging from 93% to 96%. The overall susceptibility to rubella in women aged 18–44 years had reduced significantly from 15.8% in 2004 to 11.0% in 2010. The prevalence of IgG antibody against rubella among Singapore children aged 1–17 years was maintained at 87.3% in 2008–2010.ConclusionAll available data indicated that Singapore has made good progress towards the elimination of rubella and CRS. It has attained the targets set by the WHO WPRO for 2015. In preparation for verification of rubella elimination, an enhanced surveillance system has been implemented to ensure that all reported cases are laboratory confirmed, and genotyping of rubella virus strains isolated is carried out to provide evidence for interruption of endemic transmission.     

Reducing global disease burden of measles and rubella: report of the WHO Steering Committee on research related to measles and rubella vaccines and vaccination, 2005

The WHO Steering Committee reviewed and evaluated the progress towards global control of measles and rubella and provided guidelines for future research activities concerning both diseases during its meeting in New Delhi, in April 2005. Global measles vaccination coverage increased from 71% in 1999 to 76% in 2004 and indigenous transmission was interrupted or kept at very low levels in many countries. However, Africa and Southeast Asia continue to experience endemic transmission and high mortality rates, despite a global mortality reduction of 39% between 1999 and 2003. On the basis of reports from countries with continued indigenous measles virus transmission, future control strategies as well as advantages and potential drawbacks of global measles eradication were discussed. Similarly the burden of rubella and congenital rubella syndrome (CRS) as well as the cost-effectiveness of rubella vaccination was assessed using different methods in several countries without vaccination programs. As measles and rubella viruses continue to circulate surveillance and control strategies need further optimization. RT-PCR was considered as an alternative method for laboratory diagnosis of CRS. The value of dried blood spots and oral fluid as alternative samples for measles and rubella IgG and IgM detection and genotype determination was evaluated. However further validation of these methods in different settings is required before their routine use can be recommended.     

Geographic variation in infant loss of maternal measles antibody and in prevalence of rubella antibody

Maternal and cord measles and rubella antibodies were compared in 15 populations from Brazil, Ecuador, Chile, India, Jordan, Nigeria, South Africa, Taiwan, and the United States. Review of the literature concerning these countries showed that a higher proportion of children 6-12 months of age responded immunologically to measles vaccine in areas with low per capita product than in wealthier populations. The authors show that this difference reflects differences in maternal antibody titer and differences in efficiency of transport of measles immunity across the placenta. No variation in the half-life of passive measles immunity in the infant was found in comparing three geographic areas. When these biologic factors are fully evaluated, it should be possible to predict the response to be expected from vaccination at any particular age without directly testing the vaccine in children below and above generally recommended ages for vaccination. With regard to rubella, high antibody prevalence rates were found in most of the developing countries, as well as in the United States, and these countries are therefore unlikely to encounter widespread problems with congenital rubella. However, Taiwan, and all of four areas of Brazil have prevalence rates which are no higher than those which pertained in the United States prior to establishment of the rubella immunization program. The authors believe that protection of the infants in these countries is a matter of high priority, but that, if approached hastily, it could exacerbate the problem.