Humoral immunogenicity to measles,rubella, and varicella-zoster vaccines in biliary atresia children

To investigate the humoral immune response to measles, rubella, and varicella-zoster virus (VZV) vaccines in biliary atresia (BA) children before liver transplantation, we conducted the cross-sectional designed study. Fifty BA children (age, 3.6 ± 0.2 years; 24 girls) who had not yet received liver transplantation, and another 150 healthy controls (age, 4.0 ± 0.1 years; 78 girls) were recruited into this study to evaluate their primary humoral immune response to measles, rubella, and VZV vaccines. All of these BA children (n = 50) and controls (n = 150) received one dose of measles, one dose of measles–mumps–rubella (MMR), and one dose of VZV vaccine before our assessment. Serum samples were collected at least 1 month after the vaccination and serum immunoglobulin G (IgG) antibody to measles, rubella, and VZV were then determined by qualitative enzyme-linked immune-sorbent assay. The prevalence of seropositive rate of measles IgG antibody (84% vs. 96.7%; P = 0.002), rubella (82.0% vs. 98.7%; P < 0.001), and VZV (74% vs. 95.3%; P < 0.001) were significantly different between BA children and the controls after regular measles, MMR, and VZV vaccination before 2 years of age. In those BA children with seronegative VZV antibody after vaccination, two had VZV infection after the liver transplantation. This study indicated that humoral immunity to rubella, measles and VZV vaccines are significantly lower in BA children than the normal population by standard vaccine schedule.     

HLA genotypes and rubella vaccine immune response: Additional evidence

Recent population-based studies have demonstrated the genetic heritability of rubella vaccine response and assessed that the HLA system may explain about 20% of the inter-individual variance in humoral immune response to this vaccine. Our earlier studies compared HLA allelic associations with rubella vaccine-specific antibodies between two smaller cohorts of healthy Rochester, MN, children (346 and 396 subjects) after two doses of rubella-containing vaccine. This study found that specific HLA alleles were consistently associated with rubella-specific antibody titers (B*27:05, DPA1*02:01, and DPB1*04:01 alleles). The current study examined HLA associations in an independent larger cohort of 1012 healthy San Diego, CA, subjects (age 19–40 years) after rubella vaccine in order to replicate our previous findings in the Rochester subjects. Two HLA associations of comparable magnitudes were consistently observed between B*27:05 (median NT₅₀ Rochester cohort 48.9, p = 0.067; San Diego cohort 54.8, p = 0.047) and DPB1*04:01 (median NT₅₀ Rochester cohort 61.6, p < 0.001; San Diego cohort 70.8, p = 0.084) alleles and rubella virus-neutralizing antibody titers. Additional HLA alleles resulted in consistent effects on IL-6 production in both cohorts, but did not meet criteria for statistical significance. Our data suggest these HLA alleles play a role in rubella vaccine-induced immunity and provide the basis for future studies that may explain the mechanism(s) by which these HLA polymorphisms affect immune responses to rubella vaccine.     

Models of strategies for control of rubella and congenital rubella syndrome—A 40 year experience from Australia

We investigated the impact of vaccination on rubella epidemiology in Australia, using a mathematical model fitted to Australian serosurvey data and incorporating pre-vaccination European estimates of rubella transmissibility. Mass infant measles–mumps–rubella (MMR) vaccination produced a 99% reduction in both rubella and congenital rubella syndrome (CRS) incidence by 2010 compared to the pre-vaccination era (1960–70). The model is consistent with reductions in CRS based on surveillance of congenital hearing impairment. Model simulations suggest that selective schoolgirl vaccination (1971–88) was associated with a 90% reduction in CRS incidence, but only a 1–4% reduction in rubella incidence. Our model predicted that these reductions in rubella were much less vulnerable to reductions in MMR vaccine coverage than for measles. In the future, a less than 15% decrease in MMR vaccine coverage is estimated to have minimal impact before 2060, but a 20% reduction may result in a 7-fold increase in rubella incidence, with the effective reproductive number R rising from 0.28 to 0.78 by 2060. The 99% reduction in both rubella and CRS incidence and low effective reproductive number (R ≤ 0.28) we documented after 2010 are consistent with Australia having achieved rubella elimination.     

Replication of rubella vaccine population genetic studies: Validation of HLA genotype and humoral response associations

Purported genetic associations found in population studies require validation for confirmation. We previously reported rubella vaccine-induced immune responses and HLA associations in 346 adolescents, age 12–18 years (1st cohort), following two doses of a rubella-containing vaccine. We sought to replicate the associations discovered in that work by verifying these associations in a new cohort of 396 subjects, age 11–19 years (2nd cohort), all having had two doses of a rubella-containing vaccine. We found that B*2705 (median 1st cohort 20.9 IU/ml, p = 0.028; 2nd cohort 20.5 IU/ml, p = 0.001) and DPA1*0201 (median 1st cohort 32.5 IU/ml, p = 0.048; 2nd cohort 25.8 IU/ml, p = 0.025) alleles were consistently associated with lower rubella-induced antibodies. Further, DPB1*0401 (median 1st cohort 43.5 IU/ml, p = 0.021; 2nd cohort 36.2 IU/ml, p = 0.002) alleles were associated with higher antibody levels in both populations. The association of DRB1*04-DQB1*03-DPB1*03 (mean 1st cohort 25.2 IU/ml, p = 0.011; 2nd cohort 21.4 IU/ml, p = 0.032) and DRB1*15/16-DQB1*06-DPB1*03 (1st cohort 16.3 IU/ml, p = 0.043; 2nd cohort 19.1 IU/ml, p = 0.023) haplotypes with lower rubella-specific antibodies was observed in both studies. This study provides confirmatory evidence for an association between specific class I and II HLA markers and haplotypes with rubella vaccine-induced humoral responses and lends further weight to their influence on rubella immune responses.     

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.     

Rubella seroprevalence in the first birth cohort reaching fertility age after 20 years of two dose universal vaccination policy in Israel

Background

A national program of a 2-dose universal childhood MMR vaccination policy has been in effect in Israel since 1988. As the 1988 birth cohort reached fertility age, questions regarding immunity against rubella were raised.

Objective

To assess the seroprevalence of rubella IgG antibodies among young Israeli adults born after 1987 in comparison to previous birth cohorts, in order to determine evidence based policy for prevention of rubella and congenital rubella syndrome.

Methods

We conducted a seroprevalence study of rubella IgG antibodies among 416 Israeli adults (42.5% females) born in 1988–1989, based on a representative sample of sera collected at age 18–19 upon recruitment to mandatory military service in 2007.

Results

In total, 87.7% were seropositive (>15 IU/ml) as compared with 84.8% in the 1999 recruitment (P = 0.26) and 93.4% in 1987 (P = 0.004). Yet there was a difference by gender. The proportion of seropositives among female young adults (92.7%) was significantly lower as compared to those measured in the 1999 (99.2%, P = 0.001) and 1987 (99.0%, P = 0.006) recruitments. The proportion of seropositives among males (84.1%) was significantly higher as compared to those measured in 1999 (73.0%, P < 0.001) but similar to those of 1987 (88.8%, P = 0.13). Females born in the FSU were found to be high risk groups as 11.5% were seronegative.

Conclusions

Our findings indicate that despite a successful program of congenital rubella syndrome prevention in Israel, there is a decline in seroprevalence among female young adults, especially immigrants from the FSU. A proactive catch-up program for females, especially for those of higher risk for susceptibility should be considered in Israel and in other countries.     

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 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.     

Protease and helicase domains are related to the temperature sensitivity of wild-type rubella viruses

Wild-type rubella viruses grow well at 39 °C (non-temperature sensitivity: non-ts), while vaccine strains do not (temperature sensitivity: ts). Histidine at position 1042 of the p150 region of the KRT vaccine strain was found to be responsible for ts, while wild-type viruses had tyrosine at position 1042 (Vaccine 27; 234-42, 2009). The point-mutated virus (Y1042H) based on the wild-type unexpectedly showed little reduction in growth at 39 °C. In this report, several recombinant viruses were characterized, and point-mutated Y1042H together with the p90 region of KRT significantly reduced virus growth, compared to the parental wild-type virus. There was one amino acid difference at position 1497 of the helicase domain in the p90 region. Double mutation involving both positions 1042 and 1497 markedly reduced virus growth at 39 °C, but single substitution at 1497 did not. The other vaccine strain (TO-336vac) was investigated, and serine at position 1159 of the protease domain in p150 was a crucial amino acid for ts and non-ts characteristics among four amino acid substitutions between TO-336vac and the wild-type. Our results suggest that protease and helicase domains in non-structural protein were consistent with ts phenotype, possibly related to the attenuation process of wild-type viruses.     

Estimating the burden of rubella virus infection and congenital rubella syndrome through a rubella immunity assessment among pregnant women in the Democratic Republic of the Congo: Potential impact on vaccination policy

BackgroundRubella-containing vaccines (RCV) are not yet part of the Democratic Republic of the Congo’s (DRC) vaccination program; however RCV introduction is planned before 2020. Because documentation of DRC’s historical burden of rubella virus infection and congenital rubella syndrome (CRS) has been minimal, estimates of the burden of rubella virus infection and of CRS would help inform the country’s strategy for RCV introduction.MethodsA rubella antibody seroprevalence assessment was conducted using serum collected during 2008–2009 from 1605 pregnant women aged 15–46 years attending 7 antenatal care sites in 3 of DRC’s provinces. Estimates of age- and site-specific rubella antibody seroprevalence, population, and fertility rates were used in catalytic models to estimate the incidence of CRS per 100,000 live births and the number of CRS cases born in 2013 in DRC.ResultsOverall 84% (95% CI 82, 86) of the women tested were estimated to be rubella antibody seropositive. The association between age and estimated antibody seroprevalence, adjusting for study site, was not significant (p = 0.10). Differences in overall estimated seroprevalence by study site were observed indicating variation by geographical area (p ⩽ 0.03 for all). Estimated seroprevalence was similar for women declaring residence in urban (84%) versus rural (83%) settings (p = 0.67). In 2013 for DRC nationally, the estimated incidence of CRS was 69/100,000 live births (95% CI 0, 186), corresponding to 2886 infants (95% CI 342, 6395) born with CRS.ConclusionsIn the 3 provinces, rubella virus transmission is endemic, and most viral exposure and seroconversion occurs before age 15 years. However, approximately 10–20% of the women were susceptible to rubella virus infection and thus at risk for having an infant with CRS. This analysis can guide plans for introduction of RCV in DRC. Per World Health Organization recommendations, introduction of RCV should be accompanied by a campaign targeting all children 9 months to 14 years of age as well as vaccination of women of child bearing age through routine services.     

Associations between race,sex and immune response variations to rubella vaccination in two independent cohorts

Introduction

Immune response variations after vaccination are influenced by host genetic factors and demographic variables, such as race, ethnicity and sex. The latter have not been systematically studied in regard to live rubella vaccine, but are of interest for developing next generation vaccines for diverse populations, for predicting immune responses after vaccination, and for better understanding the variables that impact immune response.

Methods

We assessed associations between demographic variables, including race, ethnicity and sex, and rubella-specific neutralizing antibody levels and secreted cytokines (IFNγ, IL-6) in two independent cohorts (1994 subjects), using linear and linear mixed models approaches, and genetically defined racial and ethnic categorizations.

Results

Our replicated findings in two independent, large, racially diverse cohorts indicate that individuals of African descent have significantly higher rubella-specific neutralizing antibody levels compared to individuals of European descent and/or Hispanic ethnicity (p < 0.001).

Conclusion

Our study provides consistent evidence for racial/ethnic differences in humoral immune response following rubella vaccination.     

湛江市2006-2007年麻疹与风疹监测结果分析

目的 分析湛江市麻疹疑似病例的血清学实验室诊断符合率和风疹检测结果,完善麻疹监测网络实验室检测工作,为进一步提高麻疹、风疹的病例诊断提供依据.方法 应用ELISA法检测全市送检的血清样本中麻疹和风疹IgM抗体,对检测结果和病例资料进行分析.结果 实验室检测麻疹疑似病例血清样本747份,检出麻疹IgM抗体阳性502例,实验室诊断符合率为67.20%;在麻疹IgM抗体阴性血清样本中榆测风疹IgM抗体245份,阳性48例,阳性检出率为19.59%.麻疹发病高峰时间主要集中在3-7月,占病例总数的78.29%,风疹发病时间主要在4月和12月;麻疹发病年龄以0～9岁居多,占病例总数的73.31%,风疹发病年龄集中在15～24岁;麻疹、风疹病例的户籍分布均以本市户口为主,占病例总数的99%以上;麻疹男女比例为1.55:1,风疹男女比例为1.09:1;无免疫接种史或接种史不详的麻疹病例占95.02%,风疹病例占97.92%.结论 近两年,我市麻疹疫情上升较快,说明我市目前还没有形成足够保护易感人群的免疫屏障,全市计划免疫工作有待进一步加强;同时也应加强对风疹的控制.     

天津市麻疹风疹及流行性腮腺炎抗体水平分析

目的了解天津市健康人群麻疹、风疹、流行性腮腺炎抗体水平,评价疫苗接种需求。方法2007年3月采集0~57岁健康人群608人份血样品,用ELISA方法定量检测麻疹、风疹、流行性腮腺炎IgG抗体水平。运用直线相关分析抗体阳性率,保护率GMC与疾病发病率之间的关系,P0.05为差异有统计学意义。结果麻疹、风疹和流行性腮腺炎疫苗接种率分别为70.39%、16.78%和12.34%;抗体阳性率分别为91.78%,65.79%和73.52%;抗体几何平均浓度(GMC)分别为2 488.10 IU/L、200.4 IU/ml和759.91 U/ml。麻疹抗体阳性率,保护率与发病率存在明显相关关系(P0.01),而GMC与麻疹发病率没有显著性相关;风疹和流行性腮腺炎抗体阳性率、GMC与发病率无相关关系。结论本次调查显示2007年天津市麻疹人群抗体GMC总体保持在较高水平。风疹、流行性腮腺炎疫苗接种率和抗体水平较低,2剂次的麻腮风疫苗(MMR)纳入免疫规划既有助于消除麻疹,也有利于控制风疹和流行性腮腺炎。     

Determining rubella immunity in pregnant Alberta women 2009–2012

Rubella IgG levels for 157,763 pregnant women residing in Alberta between 2009 and 2012 were analyzed. As there have been no reported cases of indigenous rubella infection in Canada since 2005, there has been a lack of naturally acquired immunity, and the current prenatal population depends almost entirely on vaccine induced immunity for protection. Rubella antibody levels are significantly lower in younger maternal cohorts with 16.8% of those born prior to universal vaccination programs (1971–1980), and 33.8% of those born after (1981–1990) having IgG levels that are not considered protective (<15 IU/mL). Analysis across pregnancies showed only 35.0% of women responded with a 4-fold increase in antibody levels following post-natal vaccination. Additionally, 41.2% of women with antibody levels <15 IU/mL had previously received 2 doses of rubella containing vaccine. These discordant interpretations generate a great deal of confusion for laboratorians and physicians alike, and result in significant patient follow-up by Public Health teams. To assess the current antibody levels in the prenatal population, latent class modeling was employed to generate a two class fit model representing women with an antibody response to rubella, and women without an antibody response. The declining level of vaccine-induced antibodies in our population is disconcerting, and a combined approach from the laboratory and Public Health may be required to provide appropriate follow up for women who are truly susceptible to rubella infection.     

A rubella outbreak investigation and BRD-II strain rubella vaccine effectiveness study,Harbin city,Heilongjiang province,China, 2010–2011

Background

In the 1990s, China introduced rubella vaccine into the private market using BRD-II virus strain, which is different than the globally used RA27/3 strain. In 2007, BRD-II rubella containing vaccine was introduced into the national immunization program and recommended for routine use. However, to our knowledge, there are no field vaccine effectiveness (VE) studies of BRD-II rubella vaccine. In April 2011, a rubella outbreak was detected in two daycare centers in Harbin city, China. We conducted an investigation to determine VE of BRD-II rubella vaccine.

Methods

Rubella cases were either laboratory-confirmed or epidemiologically linked to laboratory-confirmed cases. We collected demographic characteristics, migrant status, and history of rubella and measles vaccination from all children in the two daycare centers.

Results

The first case of rubella was on 22 November, 2010. Among the 143 children in the two daycare centers, 22 acquired rubella, for an overall attack rate (AR) of 15.4% (22/143). The AR in higher-grade classes (21.7%) was higher than in lower grade classes (3.9%). The AR among migrant children (47.8%) was higher than among local children (9.2%). Rubella vaccine coverage was 17% (24/143), while measles vaccine coverage was 100%. The AR among rubella-vaccinated children was 0% (0/24), and the AR among rubella-unvaccinated children was 18.5% (22/119), for a VE of 100% (P value = 0.025, 95% CI: 35–100%). Rubella vaccine coverage among children born before 2007 was 10.2% (10/98), and was lower than that for children born in 2007 or after (31.1% (14/45), RR = 0.33, 95%CI: 0.16–0.68). Emergency vaccination was conducted on 11 and 12 April 2011, and the outbreak stopped in one week later.

Conclusions

Domestic BRD-II strain rubella vaccine showed high vaccine effectiveness against rubella. Rubella vaccine coverage through routine immunization was insufficient. Consideration should be given for measuring rubella vaccine coverage to determine the need for catch-up vaccination in China.     

Seroprevalence of low rubella IgG antibody levels among antenatal women in England tested by NHS Blood and Transplant: 2004-2009. Is rubella susceptibility increasing?

Antenatal testing for rubella susceptibility is undertaken to identify women at risk of exposure during pregnancy and to target post-partum immunisation. To evaluate the current rubella control programme and to inform future planning, data on anti-rubella IgG levels in antenatal sera tested by NHS Blood and Transplant were reviewed. The frequency of women with anti-rubella IgG <10 IU/mL increased by 60% over the 6-year study period and rates were significantly higher among younger women. The screening cut-off level of 10 IU/mL, used to identify women at risk, was determined in 1995 on the basis of early epidemiological studies and the correlates for protection now need review to support the appropriate management of a young immunised antenatal population. Ethnic minorities continue to be at increased risk of rubella susceptibility re-inforcing the need to identify and opportunistically immunise these women.     

High rate of rubella seronegativity in perinatally-infected HIV women of childbearing age: A case-control study

Rubella infection is a vaccine preventable disease. Maternal infection during pregnancy may lead to congenital infection and severe foetal malformations. Thanks to antiretroviral therapy, perinatally HIV-infected women have better prognosis and are now experiencing pregnancy. We evaluated the rate of rubella seronegativity in a cohort of HIV perinatally-infected women of childbearing age. A high rate of seronegativity was found in this group as compared to age-matched non-perinatally infected HIV-infected women (34.5% vs 6.90%, p < 0.01). MMR administration before rubella testing was identified in 75.8% of perinatally-infected women (22/29) with a mean of 2 doses (range: 1–3 doses). HIV perinatally-infected women of childbearing age should be screened repeatedly for rubella immunity.     

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.