Rubella seronegativity in antenatal screening – Is it influenced by the introduction of universal childhood rubella immunization?

ObjectiveThis study examined the impact of rubella immunization, implemented in Hong Kong in phases since 1978, on antenatal rubella serological status in Chinese women.MethodsIn a retrospective cohort study, the incidence of antenatal rubella seronegative status in our parturients managed from 1998 to 2013 was analyzed by their year-of-birth as follows: <1965 (no childhood immunization), 1965–1982 (single dose at Primary 6), and ≥1983 (two doses at age 12 months and 12 years), adjusting for other factors including age, parity, body mass index, place-of-birth status and hepatitis B surface antigen (HBsAg) status.FindingsRubella seronegativity decreased from 12.9%, 10.5%, to 9.8% respectively, and correlated inversely (P < 0.001) with year-of-birth cohorts. Despite similar demographic profiles, this correlation was found only in Hong-Kong-born women (from 12.6%, 7.5% to 6.5% respectively), who also had significant lower incidences of rubella seronegativity (OR 0.73, 0.31 and 0.29 respectively) and HBsAg seropositivity (OR 1.09, 0.63 and 0.48 respectively) than China-born women. On regression analysis, rubella seronegativity was actually significantly increased following the implementation of immunization (aOR 1.20) while it was the reverse for non-residents (aOR 0.61).ConclusionAlthough rubella seronegativity decreased with immunization, the effect was less than expected when adjusted for other risk factors.     

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.     

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.     

Geographic origin and risk for congenital infection in a Canadian inner city: findings and implications for policy

This study examines associations between geographic origin and risk for congenital infections, through a chart review of women from the St. James Town area of Toronto delivering at Wellesley Hospital in 1996. Foreign-born women (n = 203) were significantly less likely than Canadian-born women (n = 53) to be HBsAg negative (187/193 vs. 48/48; RR = 0.97, 95% CI 0.94-0.99). There was no significant difference in rubella seronegativity, but rubella immunity was unacceptably low in both groups (less than 90%). A number of rubella non-immune women had delivered previously in Canada. Procedures must be implemented to ensure completion of hepatitis B immunization series in affected newborns, and rubella immunization in seronegative women prior to discharge. As well, updating immunization status most become a routine part of the immigration medical examination.     

Reasons for rubella susceptibility among pregnant women in west Lambeth.

One hundred and thirty-three pregnant women who delivered at St Thomas' Hospital, in 1990 were noted to require rubella vaccination post partum. Fifty-three (39%) had completed a telephone questionnaire in order to determine reasons for susceptibility to rubella. Laboratory reports confirmed that 92 women were rubella seronegative and 27 had low levels of antibody. Of the 53 women interviewed, 25 gave a history of one or more rubella immunizations, 20 had no history of immunization and vaccination history was unknown for eight. Eleven of the 20 unvaccinated women had not been at school in the UK between 11 and 14 years of age. Eighty-seven per cent of the patients' general practitioners had no knowledge of their patients' rubella antibody status. Ninety-four per cent of the 133 women received rubella vaccine post partum. The Department of Health guidelines should be more vigorously implemented in order to identify and immunize remaining rubella susceptible women of child-bearing age. Susceptibility among women with a history of rubella immunization suggests that the seroconversion rate following rubella immunization in clinical practice may be lower than in vaccine trials.     

Rubella serosurveys at three Aravind Eye Hospitals in Tamil Nadu, India

OBJECTIVE: To determine the susceptibility of female eye hospital staff to rubella infection and the potential risk for hospital-based rubella outbreaks. METHODS: A prospective cohort study on the seroprevalence of rubella IgG antibodies was conducted at three large eye hospitals in Coimbatore, Madurai and Tirunelveli, Tamil Nadu, India, where young children with eye abnormalities attributable to congenital rubella are treated. A total of 1000 female hospital employees aged 18-40 years agreed to participate and gave written informed consent. FINDINGS: The proportions of rubella-seronegative women were: 11.7% at Coimbatore, with a 95% confidence interval (CI) of 8.1-16.5; 15% at Madurai (95% CI = 12.3-18.1), and 20.8 at Tirunelveli (95% CI = 14.7-28.6). For the entire cohort the proportion seronegative was significantly higher among married women (21.5%) than among single women (14.0%) (P = 0.02). Rates of seronegativity were highest among physicians and lowest among housekeepers. All 150 seronegative women in the study sample accepted a dose of rubella vaccine. CONCLUSION: These are the first rubella serosurveys to have been reported from eye hospitals in any country. The relatively high rate of susceptibility indicated a risk of a rubella outbreak, and this was reduced by vaccinating all seronegative women. A policy has been established at all three hospitals for the provision of rubella vaccine to new employees. Other hospitals, especially eye hospitals and hospitals in countries without routine rubella immunization, should consider the rubella susceptibility of staff and the risk of hospital-based rubella outbreaks.     

Increasing rubella seronegativity despite a compulsory school law.

To determine if lower rubella susceptibility persisted five to seven years after immunization legislation, we retrospectively reviewed the serologic status of 341 outpatients from 1985 to 1987 in an inner-city school age population. Seronegative rates increased significantly during the two-year study period from 4.2 to 24.5 percent (17 percent overall). (Beta = 6.8%, 95% CI = 3.3, 10.3). Charts were reviewed for 57 of 58 seronegative and 114 seropositive controls. Estimates were then made to the population of 341 subjects. Those with documented rubella immunization had a seronegative rate of 13 percent compared to 19 percent if the immunization status was unknown. For patients who received care in our clinic for less than two years, 32 percent were seronegative compared to 10 percent for those treated greater than or equal to 2 years (odds ratio = 0.31, 95% CI = 0.16, 0.60). Among patients immunized in 1977 or 1978, 33 percent were seronegative compared to 7 percent immunized at other times (OR = 0.21, 95% CI = 0.07, 0.63). Factors associated with increased rubella seronegativity include immunization in 1977 or 1978 and lack of continuity of care in our clinic. Much of the increase remains unexplained.     

Rubella seroprevalence in an unvaccinated pregnant population in Malatya, Turkey

BACKGROUND: Controlling congenital rubella by 2010 is one of the targets of the World Health Organization. Most European countries currently include rubella vaccine in their national immunization programmes, but not yet in Turkey. OBJECTIVES: To define rubella seroprevalence in pregnancy in Malatya, Turkey. STUDY DESIGN: A cross-sectional interview survey was conducted among pregnant women living in Malatya province from November 2003 to May 2004, together with a follow-up component. METHODS: Stratified probability proportional to size sampling methodology. A total of 824 pregnant women from 60 clusters were enrolled. After obtaining informed consent, participants' socio-demographic and fertility characteristics were collected by interview questionnaire. Various blood samples were drawn. After storing serum samples at -20 degrees C for 6 months, anti-rubella IgM and IgG titres were studied by micro ELISA. Only 803 sera were eligible for serological study. RESULTS: Of the 803 samples tested for rubella antibodies, 753 cases (93.8%) had anti-rubella IgG positivity, indicating past infection. Five of the pregnant women (0.6%) had both anti-rubella IgM and IgG positive results, suggesting a recent infection. The remaining 45 women (5.6%) were seronegative for both antibodies. Seroprevalence was not associated with age or urban/rural residency. All the five anti-rubella IgM positive women were in the second trimester of pregnancy. CONCLUSIONS: As 5.6% of pregnant women were susceptible to rubella during pregnancy, and five of them had already had a recent infection, immunization efforts should be directed at babies and adolescents.     

Seroprevalence of rubella antibodies and determinants of susceptibility to rubella in a cohort of pregnant women in Canada, 2008–2011

Long term control of rubella and congenital rubella syndrome relies on high population-level immunity against rubella, particularly among women of childbearing age. In Canada, all pregnant women should be screened so that susceptible new mothers can be offered vaccination for rubella before discharge. This study was undertaken to estimate rubella susceptibility in a cohort of pregnant women in Canada and to identify associated socio-economic and demographic factors. Biobanked plasma samples were obtained from the Maternal-Infant Research on Environmental Chemicals (MIREC) study, in which pregnant women were recruited between 2008 and 2011. Socio-demographic characteristics and obstetric histories were collected. Second trimester plasma samples (n = 1,752) were tested for rubella-specific IgG using an in-house enzyme-linked immunosorbent assay. The percentage of women with IgG titers <5 IU/mL, 5–10 IU/mL, and ≥10 IU/mL were 2.3%, 10.1%, and 87.6%, respectively. Rates of seronegativity, defined as <5 IU/mL, were 3.1% in women who had no previous live birth and 1.6% in women who had given birth previously. Among the latter group, seronegativity was higher in women with high school education or less (adjusted OR (aOR) 5.93, 95% CI 2.08–16.96) or with a college or trade school diploma (aOR 3.82, 95% CI 1.45–10.12), compared to university graduates, and those born outside Canada (aOR 2.60, 95% CI 1.07–6.31). In conclusion, a large majority of pregnant women were found to be immune to rubella. Further research is needed to understand inequalities in vaccine uptake or access, and more effort is needed to promote catch-up measles-mumps-rubella vaccination among socioeconomically disadvantaged and immigrant women of childbearing age.     

Seroprevalence of Bordetella pertussis antibodies and anti-pertussis antibody response after a single dose of reduced-antigen combined diphtheria,tetanus, and acellular pertussis vaccine (Tdap) in pregnant Thai women

BackgroundMaternal immunization with tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccine (Tdap) has recently been implemented to prevent infant pertussis. Tdap is still not routinely recommended in Thailand, and there are limited data to support or challenge this strategy.ObjectivesThe primary aim was to determine the seroprevalence of anti-pertussis toxin antibodies (anti-PT IgG) among pregnant Thai women. The secondary aims were to evaluate antibodies response after Tdap vaccination between seronegative and seropositive mothers and to compare the different antibody titers at delivery among seropositive mothers who received Tdap to those who received tetanus-diphtheria vaccine (Td).MethodsThis randomized clinical trial was conducted during April 2018 to April 2019 at Siriraj Hospital, Bangkok, Thailand. A total of 129 pregnant women were included. Paired blood samples for anti-PT IgG levels were obtained during the first antenatal visit and at delivery. A baseline cut-off value of <5 IU/ml indicated seronegativity. There were 29 exclusions from the original 129 enrollment. All seronegative participants (n = 69) received Tdap, while the seropositive group were randomized 1:1 to receive either Tdap (n = 18) or Td (n = 13) during 27–36 weeks’ gestation. The antibody levels from both sera were compared between groups.ResultsThe seroprevalence of maternal anti-PT IgG was 33.3% (43/129). There was no significant difference in the increment of antibody levels after Tdap vaccination between the seronegative and seropositive groups (30.2 vs. 42 IU/ml; p = 0.183). Among seropositive groups, all Tdap recipients had increased antibody titers at delivery, while all Td recipients showed waning of immunity throughout gestation. (42 IU/ml vs. −7.4 IU/ml; p < 0.001).ConclusionMost pregnant Thai women have seronegative against pertussis. Most seropositive mothers had initial low antibody titers and their immunity significantly decreased before delivery. Our findings highlight the need for universal pertussis immunization in pregnancy regardless of individual baseline immunity.     

Seroprevalence of measles and rubella antibodies in pregnant women Haiti, 2012

Background

Haiti had set a national goal to eliminate measles and rubella, as well as congenital rubella syndrome (CRS) by 2010. A 2007–2008 nationwide measles and rubella vaccination campaign targeting 1–19 years, however, reached only 79% of the target population. To assess whether population immunity was adequate to support elimination, we conducted a national serosurvey.

Methods

We systematically selected 740 serum specimens collected from pregnant women in a 2012 national antenatal HIV sentinel serosurvey across four age strata: 15–19, 20–24, 25–29 and 30–39 years. Sera were tested for measles and rubella specific immunoglobulin G antibodies (IgG) using commercial immunoassays. We classified sera as seropositive, seronegative or indeterminate per manufacturer's instructions, and analyzed seroprevalence according to age strata, and rural or urban residence. We assessed immunity by estimating antibody concentrations in international units per milliliter (IU/mL) for seropositive and indeterminate sera. Measles IgG concentrations >0.12 IU/mL and rubella IgG concentrations >10 IU/mL were considered clinically protective.

Results

Of 740 sera, 696 (94.1%) were seropositive and 20 (2.7%) were indeterminate for measles IgG; overall 716 (96.8%) sera had IgG concentrations >0.12 IU/mL. For rubella IgG, 691 (93.4%) sera were seropositive and 1 (0.1%) was indeterminate; a total of 687 (92.8%) had IgG concentrations >10 IU/mL. Measles seropositivity varied across age strata (p = 0.003); seropositivity increased from 88.6% among 15–19 year olds to 98.4% among 30–39 year olds (Cochran–Armitage trend test ≤ 0.0001). Rubella seropositivity did not differ across age strata. There were no statistically significant differences in measles or rubella seropositivity by urban versus rural residence.

Conclusion

Despite previous low vaccination coverage for measles, results from this serosurvey indicate high levels of measles and rubella seropositivity in pregnant women, and contribute to the evidence for measles, rubella and CRS elimination from Haiti by the target date.     

Seroprevalence of antibodies against rubella virus in pregnant women in Haiti.

OBJECTIVE: To assess the seroprevalence of immunity to the rubella virus in pregnant women in Haiti attending the Obstetrics and Gynecology Department of the State University Hospital, in the capital city of Port-au-Prince, in order to help with the introduction of the rubella vaccine for the population and provide protection for women of reproductive age in the country. METHODS: This cross-sectional study was done between February 2002 and May 2002. A total of 503 pregnant women were tested for rubella-specific immunoglobulin G antibodies, using enzyme immunoassay; 8 of those women were later excluded because they did not know their age, leaving 495 women in the analysis. RESULTS: Of the 495 participants included in our analysis, 471 of them (95.2%) were seropositive; only 24 of them (4.8%) were seronegative (susceptible). A statistically significant difference (P = 0.02) was found in the rate of seronegativity for rubella virus between the pregnant women living in the Port-au-Prince area (17 of 426 women, or 4.0%) and those living in rural areas (7 of 69 women, or 10.1%). In terms of age, 81 of the 495 (16.4%) women were under 21 years ld. CONCLUSIONS: This study is an important first step in addressing the issue of prevalence of rubella virus infection among Haitian women and in dealing with the still-underrecognized public health problem of congenital rubella syndrome in Haiti. We recommend additional research that uses randomized sampling and includes a significant proportion of women from rural areas of the country.     

Seroprevalence of rubella in female migrant factory workers in Shenzhen, China

Background

Rubella remains a common disease in Mainland China and is a major cause of severe birth defects from Congenital Rubella Syndrome (CRS). Rubella-containing vaccines were not included in China's National Expanded Program of Immunization (NEPI) until December 2007. In Shenzhen, women of childbearing age make up a large percentage of its migrant factory worker population. Understanding their immunity to rubella is critical in furthering efforts towards rubella vaccination programs.

Objectives

To investigate the seronegativity of rubella antibodies and evaluate potential associates of rubella immunity among female migrant factory workers in Shenzhen, China.

Subjects and Methods

: Serum samples were collected from 518 female migrant workers, aged 18–55, working in 44 randomly selected factories in Shenzhen, China during May through June of 2009. Samples were tested for Rubella Immunoglobulin G (IgG) using a commercial Enzyme-linked immunosorbant assay kit. Self-reported vaccination histories and socio-demographic information were also collected.

Results

Of 518 female workers, 402 (77.6%) were immune to rubella. Significant differences in seronegativity were dependent on region of origin, being without a job contract, age group, marital status and seronegativity of measles.

Conclusions

Seroprevalence of antibodies to rubella in Shenzhen, China amongst female migrant workers is too low to provide immunity in the population. Given the high numbers of women of childbearing age amongst Shenzhen migrant factory workers coming from many provinces across China, local health authorities in Shenzhen should consider combining new rubella immunization programs with existing measles immunization efforts in this population.     

Seroprevalence of anti-rubella and anti-measles antibodies in women at the verge of marriage in Iran

BackgroundMeasles and rubella as two highly contagious eruptive diseases are on the agenda to be eliminated in Iran by 2020. To evaluate the seroimmunity of the future mothers against rubella and measles, a nationwide serosurvey was implemented in 10 provinces, selected at random from 31 provinces in the country.Methodsusing a multistage sampling method, 1600 participants were interviewed and blood sampled in 40 'Pre-marriage Consultation Centers' across 40 districts. Using ELISA method, the sera were tested for anti-rubella and anti-measles IgG antibodies in the National Reference Laboratory for Measles and Rubella, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.ResultsOf the 1600 initial participants, the sera of 1573 participants were tested for rubella and 1569 for measles. The total seroprevalence of anti-rubella and anti-measles antibodies were 90.6% (95%CI: 89.1 to 92.0%) and 80.7% (95%CI: 78.7 to 82.6%) respectively. After 14 years, the effect of the immunization campaign of 2003 against rubella and measles on the age group of 5 to 25 years, was still apparent, i.e., there was a sharp difference between the seroprevalence of antibody (against both measles and rubella) of those who at the time of the present study were above 18 years with the younger age cohorts. For both diseases, higher seroprevalence of antibodies was detected in women above 18 years old.ConclusionImplementation of a Supplemental Immunization activity or revision of the national immunization schedule to add a third dose of measles and rubella containing vaccine during adolescence are/might be considered as possible options for bridging the gap in the seroimmunity of the younger age groups.     

Sero-prevalence of rubella among pregnant women in India, 2017

BackgroundWe conducted a sero-survey among pregnant women attending antenatal clinics of six hospitals which also function as sentinel sites for CRS surveillance, to estimate the prevalence of IgG antibodies against rubella.MethodsWe systematically sampled 1800 pregnant women attending antenatal clinics and tested their sera for IgG antibodies against rubella. We classified sera as seropositive (titre ≥10 IU/ml), sero-negative (titre <8 IU/ml) or indeterminate (titre 8–9.9 IU/ml) per manufacturer's instructions. In a sub-sample, we estimated the titers of IgG antibodies against rubella. IgG titer of ≥10 IU/mL was considered protective.ResultsOf 1800 sera tested, 1502 (83.4%) were seropositive and 24 (1.3%) were indeterminate and 274 (15.2%) were sero-negative. Rubella sero-positivity did not differ by age group, educational status or place of residence. Three hundred and eighty three (87.8%) of the 436 sera had IgG concentrations ≥10 IU/mL.ConclusionThe results of the serosurvey indicate high levels of rubella sero-positivity in pregnant women. High sero-prevalence in the absence of routine childhood immunization indicates continued transmission of rubella virus in cities where sentinel sites are located.     

Seroepidemiology study of rubella antibodies among pregnant women from seven Asian countries: evaluation of the rubella vaccination program in Taiwan

During 2003-2004, approximately 13% of birth in Taiwan was given by foreign-born females. The aims of this study were to compare the seroprevalence of rubella antibodies between Taiwan-born and foreign-born pregnant women and evaluate the effect of rubella vaccination program in Taiwan. We reviewed the rubella antibody test results of 5007 women during routine pregnancy check-ups at Fooyin University Hospital during 1999-2002. In Taiwan-born women, rubella antibody was undetectable in 29.2%, 7.3%, and 8.3% of the cohorts born before 1971, between 1971 and 1976, and after 1976, respectively. In the cohorts born between 1971 and 1976 and after 1976, pregnant women born in China, Vietnam, Indonesia, and Philippines had significant higher chances of being susceptible. Our results suggested that the voluntary adult vaccination program was not as effective as the school or wipe-out programs. Both Taiwanese women born before 1971 and foreign-born women were more likely to be susceptible to rubella. The introduction of 'catch-up' immunization program and enforcement of the checking of immunization record and/or blood test before pregnancy for these women are necessary in preventing CRS.     

Seroprevalence of rubella in school girls and pregnant women

Many studies have been assigned to investigate the surveillance of congenital rubella syndrome, acquired rubella and seroprevalence in different countries to determine the new vaccination program and national vaccination schedules. Seroprevalence of rubella in Turkey is still insufficient and national immunization schedules do not include routine rubella vaccination. In this study we aimed to investigate the seroprevalence of rubella at child bearing age in an unvaccinated population in Adana, southern Turkey, to help determine whether routine rubella vaccination is necessary, if so when it should be administered. Ninety-four school girls aged 12–18 years living in Adana were selected for the study and stratified according to the socioeconomic status of their parents and evaluated for rubella antibodies. One hundred pregnant women aged 18–25 years and 100 pregnant women aged 26–35 years were sampled rubella antibodies. Rubella specific IgG antibody was measured qualitatively and quantitatively by using microparticule enzyme immune assay technology. Rubella specific IgG antibody was positive in 87–94 school girls (92.5%). The geometric mean rubella specific IgG antibody value was found be 148.14 IU/ml. No correlation was found between socioeconomic status and rubella seropositivity (p = 0.6521). In all pregnant women rubella specific IgG antibody was found to be positive. In conclusion rubella vaccination should be considered carefully in developing countries. Because of the high seropositivity to rubella in our region we do not recommend rubella vaccination in early childhood. Yet this is a preliminary study and further studies with larger population size are needed to determine the national immunization policy for rubella.     

Rubella and measles seroprevalence among women of childbearing age, Argentina, 2002

To assess rubella and measles susceptibility among women of childbearing age we conducted a cross-sectional seroprevalence study in four cities and one rural area in Argentina. A convenience sample of women aged 15-49 years seeking care in public health-care institutions was selected (n=2804). Serum specimens were tested for rubella and measles IgG antibody titres. The overall susceptibility to rubella and measles was 8.8 and 12.5% respectively. Seroprevalence differences were found for both rubella (P<0.001) and measles (P=0.002) across sites. Rubella seroprevalence was higher in women aged >or=40 years than in younger women (P=0.04). Measles seroprevalence tended to increase with age (P<0.001). Approximately 15% of women aged 15-29 years were not immune to measles. No risk factors were associated with rubella seronegativity; however, age (P<0.001) and having less than four pregnancies (P<0.001) were factors associated with measles seronegativity. Our findings support the introduction of supplemental immunization activities targeting adolescents and young adults to prevent congenital rubella syndrome and measles outbreaks over time.