[Seroprevalence of anti-rubella and anti-cytomegalovirus IgG antibodies in women aged between 16 and 40 years, living in Tunja, Colombia]

OBJECTIVE

To determine the seroprevalence of anti-rubella and anti-cytomegalovirus IgG antibodies in a group of women aged between 16 and 40 years, residents of Tunja.

METHODS

Descriptive, cross-sectional research in women aged between 16 and 40 years included by means of non- probability sampling for convenience. Sociodemographic variables were recorded by applying a survey. An enzyme immunoassay was used for the quantitative determination of rubella and cytomegalovirus IgG antibodies in serum. The statistical analysis was carried out using the statistical program SPSS version 21.

RESULTS

The study included 154 women of childbearing age, establishing seropositivity for anti-rubella IgG of 96.1% (n=148) (95%CI: 86.3 - 95.4).

CONCLUSION

One in ten women included in the study is at risk of primary cytomegalo-virus infection and one in 30 of rubella infection. Prenatal care using serological determinations of cytomegalovirus and rubella during pregnancy is essential in these cases.

Synthesis of Evidence to Characterize National Measles and Rubella Exposure and Immunization Histories

Population immunity depends on the dynamic levels of immunization coverage that countries achieve over time and any transmission of viruses that occur within the population that induce immunity. In the context of developing a dynamic transmission model for measles and rubella to support analyses of future immunization policy options, we assessed the model inputs required to reproduce past behavior and to provide some confidence about model performance at the national level. We reviewed the data available from the World Health Organization (WHO) and existing measles and rubella literature for evidence of historical reported routine and supplemental immunization activities and reported cases and outbreaks. We constructed model input profiles for 180 WHO member states and three other areas to support disease transmission model development and calibration. The profiles demonstrate the significant variability in immunization strategies used historically by regions and member states and the epidemiological implications of these historical choices. The profiles provide a historical perspective on measles and rubella immunization globally at the national level, and they may help immunization program managers identify existing immunity and/or knowledge gaps.

Systematic Review of Measles and Rubella Serology Studies

Serological tests provide information about individual immunity from historical infection or immunization. Cross-sectional serological studies provide data about the age- and sex-specific immunity levels for individuals in the studied population, and these data can provide a point of comparison for the results of transmission models. In the context of developing an integrated model for measles and rubella transmission, we reviewed the existing measles and rubella literature to identify the results of national serological studies that provided cross-sectional estimates of population immunity at the time of data collection. We systematically searched PubMed, the Science Citation Index, and references we identified from relevant articles published in English. We extracted serological data for comparison to transmission model outputs. For rubella, serological studies of women of child-bearing age provide information about the potential risks of infants born with congenital rubella syndrome. Serological studies also document the loss of maternal antibodies, which occurs at different rates for the different viruses and according to the nature of the induced immunity (i.e., infection or vaccine). The serological evidence remains limited for some areas, with studies from developed countries representing a disproportionate part of the evidence. The collection and review of serological evidence can help program managers identify immunity gaps in the population, which may help them better understand the characteristics of individuals within their populations who may participate in transmission and manage risks.

Serological makers of rubella infection in Africa in the pre vaccination era: a systematic review

BACKGROUND

Rubella infections in susceptible women during early pregnancy often results in congenital rubella syndrome (CRS). World Health Organisation (WHO) recommends that countries without vaccination programmes to assess the burden of rubella infection and CRS. However; in many African countries there is limited data on epidemiology of rubella infection and CRS. This review was undertaken to assess the serological markers and genotypes of rubella virus on the African continent in order to ascertain the gap for future research.

FINDINGS

A systematic search of original literatures from different electronic databases using search terms such as 'rubella' plus individual African countries such as 'Tanzania', 'Kenya', 'Nigeria' etc. and different populations such as 'children', 'pregnant women' etc. in different combinations was performed. Articles from countries with rubella vaccination programmes, outbreak data and case reports were excluded. Data were entered in a Microsoft Excel sheet and analyzed. A total of 44 articles from 17 African countries published between 2002 and 2014 were retrieved; of which 36 were eligible and included in this review. Of all population tested, the natural immunity of rubella was found to range from 52.9 to 97.9 %. In these countries, the prevalence of susceptible pregnant women ranged from 2.1 to 47.1 %. Rubella natural immunity was significantly higher among pregnant women than in general population (P < 0.001). Acute rubella infection was observed to be as low as 0.3 % among pregnant women to 45.1 % among children. All studies did not ascertain the age-specific prevalence, thus it was difficult to calculate the rate of infection with increase in age. Only two articles were found to report on rubella genotypes. Of 15 strains genotyped; three rubella virus genotypes were found to circulate in four African countries.

CONCLUSION

Despite variations in serological assays, the seroprevalence of IgG rubella antibodies in Africa is high with a substantial number of women of childbearing age being susceptible to rubella infection. Standardized sero-epidemiological data in various age groups as well as CRS data are important to implement cost-effective vaccination campaigns and control strategies.

Immunity to polio, measles and rubella in women of child-bearing age and estimated congenital rubella syndrome incidence, Cambodia, 2012

Significant gaps in immunity to polio, measles, and rubella may exist in adults in Cambodia and threaten vaccine-preventable disease (VPD) elimination and control goals, despite high childhood vaccination coverage. We conducted a nationwide serological survey during November-December 2012 of 2154 women aged 15-39 years to assess immunity to polio, measles, and rubella and to estimate congenital rubella syndrome (CRS) incidence. Measles and rubella antibodies were detected by IgG ELISA and polio antibodies by microneutralization testing. Age-structured catalytic models were fitted to rubella serological data to predict CRS cases. Overall, 29.8% of women lacked immunity to at least one poliovirus (PV); seroprevalence to PV1, PV2 and PV3 was 85.9%, 93.4% and 83.3%, respectively. Rubella and measles antibody seroprevalence was 73.3% and 95.9%, respectively. In the 15-19 years age group, 48.2% [95% confidence interval (CI) 42.4-54.1] were susceptible to either PV1 or PV3, and 40.3% (95% CI 33.0-47.5) to rubella virus. Based on rubella antibody seroprevalence, we estimate that >600 infants are born with CRS in Cambodia annually. Significant numbers of Cambodian women are still susceptible to polio and rubella, especially those aged 15-19 years, emphasizing the need to include adults in VPD surveillance and a potential role for vaccination strategies targeted at adults.

Congenital rubella syndrome and immunity status of immigrant women living in southern Italy: a cross-sectional, seroepidemiological investigation

OBJECTIVES

A National Programme to eliminate Measles and Congenital Rubella was implemented in Italy in 2003. It aimed to achieve elimination by 2010 in line with the targets set by the World Health Organization (WHO) European Region. The aim of this study was to determine the prevalence of rubella antibodies in samples of immigrant women living in southern Italy.

METHOD

A seroepidemiologic study was conducted from 1 January 2008 to June 30 2009. 489 immigrant women resident in Messina were enrolled in the study. The detection of rubella antibodies was performed using a microparticle enzyme immunoassay. A questionnaire was used to collect demographic data including age, country of origin, educational level and knowledge about rubella.

RESULTS

The results of the seroepidemiological survey to detect rubella antibodies showed an overall seropositivity rate of 82.2%. Generally, knowledge about rubella and congenital rubella syndrome was lacking.

CONCLUSION

Many immigrants are susceptible to rubella and may benefit from vaccination programmes. Additional catch-up vaccination strategies are urgently needed to eliminate the risk of congenital rubella syndrome for future generations.