Rubella-specific Antibodies Research Articles

Difficulty in Serologic Screening for Subclinical Rubella during Pregnancy.

In Japan, rubella antibodies are tested in all pregnant women to detect subclinical infections. This study aimed to assess the validity of measuring rubella antibodies for detecting subclinical rubella among pregnant women in Japan. This single-center retrospective study measured rubella hemagglutination inhibition (HI) titers and rubella-specific IgM antibody index (IgM) values. IgM values were measured by conducting enzyme immunoassay, and IgM-values >1.2 were considered positive. Of 14,965 included pregnant women, 186 (1.2%) were IgM-positive. Only one patient was clinically diagnosed with rubella (HI titer, 1:2,048; IgM value, 10) and developed fever and skin rash. She decided to terminate her pregnancy without undergoing repeated blood tests. Of the IgM-positive patients, 136 (73.1%) had rubella HI titers of < 1:256. The correlation coefficient between rubella HI and IgM titers was weakly positive (0.2527; P < 0.0001). This study showed that a single combination of rubella HI and rubella-specific IgM measurements alone could not detect subclinical rubella. Creating awareness among pregnant women by informing them that almost all rubella-specific IgM-positive individuals without symptoms are not acutely infected could decrease their anxiety and prevent unnecessary pregnancy termination.

One-point evaluation of children exposed to rubella infection In Utero in Maiduguri, North-Eastern Nigeria: A follow-up Study

Background: Rubella is a disease caused by a virus, rubella virus. Major obstetrics concerns are profound effects of the virus on developing fetuses, which may result in multiple congenital malformations. Although vaccination has reduced the incidence of rubella virus substantially; the World Health Organization (WHO) estimated that more than 100,000 cases of congenital rubella syndrome occur each year worldwide, most of them in developing countries. Diagnosis of rubella cannot be made on clinical grounds alone due to lack of specific symptoms or signs that are unique to the disease. Women infected with rubella during pregnancy are at increased risk of developing complication for the women and their fetuses. Some of these complications may not present at birth, but several years during childhood and later in life. Methodology: The main rubella sero-prevalence study was conducted in 2013, at the Department of Obstetrics and Gynaecology of the University of Maiduguri Teaching Hospital (UMTH), Maiduguri, Borno State, North-Eastern Nigeria. This is a follow-up descriptive study. The children of women who had significant titres of Immunoglobulin M antibodies, and who were negative for Immunoglobulin G antibodies were followed during their pregnancies and childbirth. The children born to these women who acquired rubella virus infection in mid pregnancy were reviewed at 10-11 years of age, and their current state of health is reported. Their biodata, educational status, rubella serostatus, state of health, and history of vaccination with measles were obtained. Results: There were 459 pregnant women who consented and participated in the main sero-prevalence study. Four hundred twenty-one women (91.7%) women tested positive for rubella-specific IgG antibodies, and of the remaining 38 women, 6 (15.8%) were positive for IgM rubella-specific antibody. All the patients with positive IgM antibodies were followed up till birth. All the pregnancies were carried to term and delivered in hospital. None of the neonates was found to have any congenital malformation at birth. At 10 years review of the six (6) children, 1 (16.7%) child developed cataract. None of the children developed cardiac, ear, or other complications of rubella. Five (5) children (83.3%) tested positive for both IgG, one (1) was negative (the child with cataract) for rubella antibodies. None had IgM rubella antibodies. All the children were enrolled in schools and their performance is at least average of their peers. Conclusion: None of the known types of congenital rubella syndrome was found in this study, this may be as a result of smaller number of infected pregnancies. It is recommended that inclusion of rubella vaccination in the National programme on Immunization protocol will be cost effective in the prevention of rubella-associated complication in children.

Seroepidemiology study of rubella virus antibodies among neonates and pregnant women at hospitals in Henan province, China.

Rubella virus infection can cause vertical transmission to the fetus during pregnancy. In China's Henan province, rubella surveillance needs to be well-established. In this research, a total of 1933 neonates and 2502 pregnant women were enrolled, and their sera for IgG and IgM antibodies against rubella were tested by chemiluminescence assay. Of 1933 neonates' sera tested, the seropositive of rubella IgG was 68.7%. The seroprevalence of rubella IgM in neonates was 0.4%. 30.9% of neonates had negative results for IgG and IgM antibodies. Two thousand five hundred and two pregnant women participated in the serosurvey, and 79.3% were rubella IgG positive. Rubella IgG seropositivity in pregnant women differed by age and number of births. 0.8% of the pregnant women had positive results for IgM against the rubella virus. The seronegative of rubella IgG and IgM antibodies in pregnant women was 19.8%. Due to the negative rubella-specific IgG antibody, many neonates remain at risk of rubella virus infection. Rubella virus continues to spread since some neonates and pregnant women with rubella-specific IgM antibody positive have been detected. Rubella vaccination may be introduced for childbearing-age women to increase immunity levels against rubella with periodic sero-surveillance.

Sero-prevalence of rubella-specific antibodies in pregnant women attending antenatal care in Maiduguri, north-eastern Nigeria

Context: Rubella is a disease caused by a virus –rubella virus. Major obstetrics concerns are profound effects of the virus on developing fetuses, which may result in multiple congenital malformations. Although vaccination has reduced the incidence of rubella virus substantially; the world health organization (WHO) estimated that more than 100,000 cases of congenital rubella syndrome occur each year worldwide, most of them in developing countries. Diagnosis of rubella cannot be made on clinical grounds alone due to lack of specific symptoms or signs that are unique to the disease. Laboratory confirmation of suspected cases is done based on the detection of the presence of immunoglobulin M (IgM) during the acute illness or a significant rise in rubella – immunoglobulin G (IgG) antibody titres in the serum of previously infected individuals. Methodology: This is a descriptive cross-sectional study conducted at the antenatal clinic of the Department of Obstetrics and Gynaecology of the University of Maiduguri Teaching Hospital (UMTH), Maiduguri, Borno State, North-Eastern Nigeria. Eligible women who presented for booking for antenatal care at the hospital were recruited. Their bio-data, educational status, and history of vaccination with measles and previous obstetrics outcomes were obtained. Five milliliters of venous blood was taken and the serum obtained from the sample was analyzed for anti-rubella IgG antibodies. The samples that were negative for IgG were tested for IgM antibodies. Data obtained analyzed using the statistical package for social science SPSS v16.0.0 (Sept 13, 2007) Inc, Illinois, USA. Results: There were 459 pregnant women who consented and participated in the study. Their age range is 17-43 years (mean= 25.8±5.3). There were 280 (61.0%) patients who were multiparous (mean=3.5±2.1) and women with secondary education accounted for 39.4%. Four hundred twenty-one women (91.7%) women tested positive for rubella-specific IgG antibodies, and of the remaining 38 women, 6 (15.8%) were positive for IgM rubella-specific antibody. Most of the patients (98.1%) with positive IgG had serum titers in the range of 51-150U/mL. All the patients with positive IgM antibodies were followed up till birth, all the pregnancies were carried to term and none of the neonates was found to have any congenital malformation. None of the socio-demographic characteristics were found to be significantly associated with presence of IgG antibodies. Past history of abortions and congenital cataracts were significantly associated with IgG sero-positivity. Conclusion: The sero-prevalence of anti-rubella IgG sero-positivity is high in Maiduguri and this indicates high herd immunity. The number of pregnant women requiring rubella vaccination postpartum in also large. It is recommended that inclusion of rubella vaccination in the National programme on Immunization protocol will be cost effective in the control of rubella and CRS.

Seroprevalence of Rubella Virus antibodies among pregnant women in Hodeidah city, Western Yemen

Introduction: Rubella infection in early pregnancy can lead to miscarriages, fetal death, or birth of an infant with congenital rubella syndrome (CRS). Like other developing countries, in Yemen rubella surveillance is not well-established. So, the aim of this study was conducted with the objectives of estimating the seroprevalence and potential risk factors in acquiring rubella infection by pregnant women in Hodeidah city Yemen. Methods: A cross‐sectional study was conducted for rubella infection among pregnant women attending antenatal clinics in Hodeidah city, western Yemen. Demographic data, obstetric characteristics, and blood samples were collected and tested for rubella specific antibodies (IgG and IgM) by using the Electro-Chemiluminescence Immunoassay (ECLIA) technique. Results: The study revealed that Rubella virus antibodies were positive in 91.25% of the samples of which 89.2% were positive only for IgG class and 2.0% positive for both IgG and IgM antibodies. There was no statistically significant association between Rubella seropositive and all the socio-demographic characteristics and obstetric characteristics analyzed (P&gt;0.05). Conclusions: Rubella virus is endemic in Hodeidah city, Western Yemen with a high seroprevalence of IgG antibodies among pregnant women. There is a strong recommendation for Rubella screening in pregnant women and to proceed to postpartum vaccination for seronegative women.

Measles and Rubella Incidence and Molecular Epidemiology in Senegal: Temporal and Regional Trends during Twelve Years of National Surveillance, 2010-2021.

We investigated the epidemiology of measles and rubella infections in Senegal based on data from twelve consecutive years of laboratory-based surveillance (2010–2021) and conducted phylogenetic analyses of circulating measles viruses. Sera from measles-suspected cases were collected and tested for measles and rubella-specific IgM antibodies using enzyme-linked immunosorbent assays (ELISA). Throat swabs were collected from patients with clinically diagnosed measles for confirmation by reverse-transcription polymerase chain reaction (RT-PCR) and viral genotyping. Among 8082 laboratory-tested specimens from measles-suspected cases, serological evidence of measles and rubella infection was confirmed in 1303/8082 (16.1%) and 465/6714 (6.9%), respectively. The incidence of rubella is now low—0.8 (95% CI 0.4–1.3) cases per million people in 2021—whereas progress towards measles pre-elimination targets (<1.0 case per million people per year) appears to have stalled; there were 10.8 (95% CI 9.3–12.5) cases per million people in 2021. Phylogenetic analyses revealed that all Senegalese measles strains belonged to genotype B3. The rubella virus sequence obtained in this study was consistent with genotype 1C. Our national surveillance data suggest that despite their low incidence both measles and rubella remain endemic in Senegal with a concerning stagnation in the decline of measles infections that represents a significant challenge to the goal of regional elimination.

Rubella-specific IgM antibodies in non-pregnant women in Rivers State, Nigeria

Rubella can cause arthritis in some women's fingers, wrists, and knees, especially if the infection is complicated. Scarcity of information about the disease in Nigeria, and rubella vaccination is not widely available. This study aimed to look for rubella virus IgM antibodies in non-pregnant women in Rivers State. Method: Ninety-two (92) consenting non-pregnant women attending Rivers State University Teaching Hospital, Rivers State, were randomly assessed for the study. The sera were analyzed for detectable anti-rubella IgM antibodies following the manufacturer’s description using ELISA kits. Results: Of the 92 samples evaluated for rubella Immunoglobulin M antibody, 14 (15.2%) were positive, and 78 (84.8%) were negative. None of the socio-demographic factors had significant relation with Rubella anti-IgM seroprevalence (p&lt;0.05). Conclusion: The substantial frequency of IgM antibodies demonstrated the existence of the virus and the possibility of new infections of Rubella in non-pregnant women. To determine the predominance of the rubella infection and subsequently design control tactics against it, a surveillance strategy and education of women regarding the implications of the existence of IgM antibodies would be helpful.

Influence of long-term storage of blood serum samples in a biobank for population-based seroepidemiologic studies

Aim. To assess the safety of IgG antibodies during long-term storage of blood serum samples using measles- and rubella-specific antibodies as an example.Material and methods. The study used serum samples from the collection of the Department of Epidemiology of the Gamaleya National Research Center for Epidemiology and Microbiologya, which were tested for measles- or rubella-specific IgG antibodies immediately upon admission to the laboratory, were frozen and stored at -70оC (n=180). The samples were reexamined after 20 months (n=90) and 6 years (n=90).Results. Reexamination after 20-month storage showed a decrease in the mean level of measles- and rubella-specific antibodies by 13,1% (from 0,36 (0,08-1,21) to 0,31 (0,02-1,2) IU/ml) and by 11,8% (from 151,4 (45-235) to 133,5 (72-198) IU/ml), respectively (p&lt;0,05 for all). At the same time, the number of seronegative samples did not change. After a 6-year storage period, the mean level of measles-specific antibodies decreased by 33,8% (p&lt;0,05) from 0,72 (0,4-1,79) to 0,34 (0,18-1,14) IU/ml and only two samples became seronegative. It was shown that the higher the IgG level in native samples, the more pronounced its decrease was during the second examination.Conclusion. Storage of serum samples in a biobank for 20 months at -70оC ensures the safety of measles- and rubella-specific IgG antibodies, and is the basis for the reliability of future studies.

Seroprevalence of Measles-, Mumps-, and Rubella-specific antibodies in the German adult population - cross-sectional analysis of the German Health Interview and Examination Survey for Adults (DEGS1).

BackgroundThe WHO European Region targets the elimination of measles, rubella, and the congenital rubella syndrome and welcomes mumps elimination via the joint MMR vaccine. In a push towards this elimination goal, Germany introduced a recommendation on MMR vaccination for adults in 2010 to prevent increasing numbers of measles cases among adults and to strengthen herd immunity.MethodsThe prevalence of anti-measles, -mumps, and -rubella IgG antibodies was analysed in 7,115 participants between the ages of 18 and 79 years in the German Health Interview and Examination Survey. Risk factors of seronegativity of adults born 1970 or later were determined.FindingsThe seroprevalence of anti-measles IgG antibodies was more than 97% in adults born before 1965 and less than 90% in adults born afterwards. Prevalence and GMTs declined with later years of birth. Seronegativity was associated with two-sided migration background and region of residence in East Germany. For anti-mumps IgG antibodies, the seroprevalence was less than 90% in almost all age groups. Prevalence and GMTs declined with later years of birth. Seronegativity was not associated with any socio-demographic factor. Anti-rubella IgG seropositivity was found in more than 90% of adults born before 1985. GMTs declined in younger age groups. Seronegativity was associated with birth between 1980 and 1993 and male gender. High socio-economic status lowered the odds of being seronegative.InterpretationThese data reinforce the implementation of the vaccination recommendation for adults and provide the basis for further evaluation of this measure.FundingThe Federal Ministry of Health, Germany.

RUBELLA OUTBREAK AMONG TRAINEES OF NATIONAL SERVICE PROGRAM IN PASIR MAS, KELANTAN, MALAYSIA

&#x0D; &#x0D; &#x0D; An outbreak occurred at the National Service Training Camp Cancun Park in Pasir Mas, Kelantan and a subsequent outbreak investigation was carried out to verify the agent of the outbreak and to recommend a control measure. Descriptive (cases series) study was carried from 13th April 2008 to 16th May 2008 at the training camp. The case definition for the outbreak was a person presenting with a maculopapular rash with or without fever from 1st April 2008 and stayed in the training camp. Confirmed cases were clinical cases positive for rubella IgM. Case findings were carried out by the medical team in the camp and from the nearest health centre where the affected person who fit in the clinical case definition was interviewed, clinically examined, and had blood investigations done. A total of 337 persons (280 trainees and 57 camp trainers) who occupied the training centre at the point of the outbreak were purposively included in this study. Out of 337 occupants of the training camp, 22 (6.5% attack rate) fulfilled the case definition and all of them were among trainees. 95% of cases were male and 86% were Malays. 100% had a maculopapular rash, 77% presented with fever, 41% presented with cough and 50% presented with conjunctivitis. Rubella-specific IgM antibody was positive in 59% (n = 13) of the cases. There was no history of vaccination for all the confirmed cases. Control measures taken were strict isolation of the affected trainees, daily surveillance of rash and fever, and health education to promote awareness on symptoms and signs, nature of transmission, prevention, and control of rubella infection to trainees. Rubella is confirmed as the cause of the outbreak based on the clinical and serological analysis. The probable source of the outbreak is the possibility of exposure during a family day at the training camp.&#x0D; &#x0D; &#x0D;

Persistence of Anti-Rubella Immunoglobulin G Antibody Titers in Young Adults Involved in a Short-Term Periodic Immunization in Japan.

In Japan, several rubella outbreaks in adults have erupted due to insufficient immunity against rubella virus (RUBV). Although selective immunization is being promoted along with routine rubella vaccination as its eradication strategy, serosurveillance against RUBV needs to be implemented in the generations corresponding to the vaccination transition period. In this study, a survey of anti-rubella immunoglobulin G (IgG) antibody titers was conducted among young adults involved in the transitional periods of the routine rubella vaccination program. Specifically, serosurveillance was performed in 370 healthy young adults aged 18-20 years, wherein their serum samples were analyzed using an enzyme immunoassay to determine rubella-specific IgG antibody titers. Although multiple regression analysis revealed significant differences only in medical history, more than 90% of participants exhibited seropositivity, excluding those who received a single-dose vaccine alone. Based on elapsed periods after the last vaccination, rubella-specific IgG antibody titers in less than a 6-year period were higher than those in more than a 10-year period. Although almost all study participants in the transitional period had seropositivity, the results may indicate that this persistence is related to past rubella outbreaks.

Population-based study of a free rubella-specific antibody testing and immunization campaign in Chiba city in response to the 2018–2019 nationwide rubella outbreak in Japan

ABSTRACT Japan has not been able to eliminate rubella; as a result, the large rubella epidemic has occurred. Considering the complicated history of the vaccine policy in Japan, some susceptible populations became infected with rubella, resulting in an outbreak. We conducted a large serosurveillance against rubella in Chiba city after initiating free rubella-specific antibody testing and an immunization campaign during 2018–2019. The total number of rubella specific antibody tests that was conducted in the nationwide campaign and Chiba city original campaign was 8277 and 6104, respectively. The proportion of participants with an antibody titer of ≤1:16 using the hemagglutination inhibition (HI) test was higher in those in their 20–30s. On the contrary, the proportion of participants with an antibody titer of <1:8 using the HI test was higher in men in their 40–50s. This discrepancy possibly reflects the complicated history of the vaccine policy. The number of participants in the nationwide immunization campaign in this city was 1517, whereas that in the Chiba city campaign was 3607. The Chiba city campaign was effective against women in their 20–30s (child-bearing generation); however, the nationwide campaign was not sufficiently effective against men in their 40–50s because many workers were did not visit medical facilities to receive the measles–rubella vaccine.

Impact of vaccination policy on changes in rubella virus antibody in Japanese pregnant women

AimAs a result of the 2012–2013 rubella epidemics in Japan, many cases of congenital rubella syndrome have been reported. Given the frequent changes to rubella vaccination policy in Japan, we investigated antibody prevalence among pregnant women according to birth year.Subjects and methodsParticipants comprised 55,400 pregnant Japanese women for whom rubella-specific hemagglutination inhibition antibody had been measured during early pregnancy in our institute from 1987 to 2016. Birth year was considered for the 47,978 cases for which age was known.ResultsThe ratio of rubella antibody-negative cases among pregnant women born after 1962 decreased significantly with mandatory vaccination. In the transition phase, during which the administration target was changed from schoolgirls to children of both sexes (born 1979–1987) as temporary vaccination, the ratio of rubella antibody-negative pregnant women started increasing in the latter period of this phase. For generations born in or after 1988, the ratio of rubella antibody-negative pregnant women clearly increased when the vaccination target changed to non-mandatory vaccination of children of both sexes.ConclusionsPrevalence of antibody titers depends on vaccine coverage rates. Suitable information needs to be provided prior to conception to all women, their husbands, and family members.

Rubella Specific IgG and IgM Antibodies among Infants before Rubella Vaccination in Dar es Salaam, Tanzania: A Cross-Sectional Study

Prevention of Rubella virus infection using rubella vaccine has been widely used in high-income countries contributing to the declining of congenital rubella syndrome. Before introduction of rubella vaccine in Tanzania October 2014, status of rubella specific antibodies in the infant was limited. This study was conducted to assess the rubella specific IgG and IgM antibodies among infants before receiving the vaccine.

Seroprevalence of rubella virus antibodies among pregnant women in the Center and South-West regions of Cameroon.

Rubella infection in early pregnancy can lead to miscarriages, fetal death, or birth of an infant with congenital rubella syndrome (CRS). In Cameroon, like in many developing countries, rubella surveillance is not well-established. The aim of this study was to determine the prevalence of rubella virus specific antibodies among pregnant Cameroonians. We conducted a cross-sectional study for rubella infection among pregnant women attending antenatal clinics in the Center and South-West regions of Cameroon. Demographic data and blood were collected and tested for rubella specific antibodies (IgG and IgM), and for the IgM positive cases, IgG avidity and real time PCR was done. From December 2015 to July 2017, 522 serum samples were collected and tested from pregnant women. The seroprevalence of rubella specific IgG was 94.4%, presumably due to immunity induced by wild-type rubella virus. The seroprevalence of rubella specific IgM was 5.0%, possibly indicating rubella infection. However, IgG avidity testing of the IgM positive cases detected high avidity IgGs, ranging from 52.37% to 87.70%, indicating past rubella infection. 5.6% (29/522) of the participants had negative results for IgG to rubella virus, indicating susceptibility to rubella infection. None of the participants had received a rubella containing vaccine (RCV), but 51% (266/522) of the pregnant women lived in a house with a child with records of at least one dose of RCV. Rubella virus RNA was not detected in the urine of any IgM positive case. Findings from this study show that rubella infection is significant in Cameroon. Some pregnant women are still susceptible to rubella infection. For a better management of rubella infection in pregnancy in Cameroon, consideration should be taken to investigate for IgG-avidity test in cases with positive rubella IgM result to distinguish between recent from past rubella infection.

Rubella virus-specific humoral immune responses and their interrelationships before and after a third dose of measles-mumps-rubella vaccine in women of childbearing age

In the U.S., measles, mumps, and rubella vaccination is recommended as two vaccine doses. A third dose of measles-mumps-rubella (MMR) vaccine is being administered in certain situations (e.g., identified seronegativity and during outbreaks).We studied rubella-specific humoral immunity (neutralizing antibody, enzyme-linked immunosorbent assay/ELISA IgG titer and antibody avidity) and the frequencies of antigen-specific memory B cells before and after a third dose of MMR-II in 109 female participants of childbearing age (median age, 34.5 years old) from Olmsted County, MN, with two documented prior MMR vaccine doses. The participants were selected from a cohort of 1117 individuals if they represented the high and the low ends of the rubella-specific antibody response spectrum. Of the 109 participants, we identified four individuals (3.67% of all study participants; 7.14% of the low-responder group) that were seronegative at Baseline (rubella-specific ELISA IgG titers <10 IU/mL), suggesting a lack of protection against rubella before receipt of a third MMR vaccine dose. The peak geometric mean neutralizing antibody titer one month following the third dose of MMR vaccine for the cohort was 243 NT50 (CI; 241, 245), which is expected for a cohort with two doses of MMR, and the peak geometric mean IgG titer was 150 IU/mL (CI; 148, 152) with no seronegative individuals at Day 28. One-third of all subjects (31.8% for the neutralizing antibody; 30.8% for the IgG titer) experienced a significant boost (≥4-fold) of antibody titers one month following vaccination. Antibody titers and other tested immune-response variables were significantly higher in the high-responder group compared to the low-responder group. The frequencies of rubella-specific memory B cells were modestly associated with the antibody titers. Our study suggests the importance of yet unknown inherent biologic and immune factors for the generation and maintenance of rubella-vaccine-induced humoral immune responses.

Seroprevalence of rubella-specific IgM and IgG antibodies among pregnant women in a Catholic Hospital in Yaoundé, Cameroon

Rubella virus (RV) infection is responsible of an unresolved clinical complication that affects newborns and children. During the first trimester of pregnancy, it often causes severe birth defects known as congenital rubella syndrome (CRS). This study reports the seroprevalence of the RV-specific IgM and IgG antibodies, its relationship with the duration of pregnancy and past history of abortion in pregnant women at Yaounde in order to help strategies to eliminate rubella and to prevent Congenital Rubella Syndrome (CRS) in Cameroon. Four Hundred (400) pregnant women were screened for rubella immunoglobulins G (IgG) and M (IgM), using the chemiluminescent microparticle immunoassay for the detection of IgG and IgM antibodies on the ARCHITECT i system at the Laboratory of Medical Analysis of Pasteur Institute, Senegal. Out of the400 pregnant women tested, 367 (91.75%) were positive for RV-IgG while only 5 (1.25%) were positive for RV-IgM. A higher number of pregnant women in the first trimester of pregnancy tested positive for IgG (91.8%). None of the possible risk factors were significantly associated with infection. The presence of rubella RV-IgM and RV-IgG in pregnant women predisposes babies to CRS and emphasizes on the initiation of a vaccination policy of those who are susceptible in Cameroon. Keywords : Antibodies, Cameroon, pregnant women, rubella, seroprevalence.

Measles and Rubella Seroprevalence in Mother-Infant Pairs in Rural Nepal and the United States: Pre- and Post-Elimination Populations.

.We sought to compare seroprevalence of protective measles and rubella-specific antibody in mother–infant pairs across two populations: a pre-disease elimination Nepal population with recently introduced rubella vaccine and post-disease elimination U.S. population. Qualitative measles and rubella immunoglobulin G was assessed in maternal serum and cord blood from 258 pairs in Nepal, 2012–2013 and 49 pairs in Seattle, WA, 2014–2015. High rates of protective antibody were observed in both populations. Two hundred and forty-four (95%) pregnant women in Nepal had protective measles antibody versus 44 (92%) in Seattle (P = 0.42). Ninety-six percent of infants in Nepal (N = 246) and Seattle (N = 43) had protective measles antibody (P = 0.75). Ninety-four percentage of pregnant women in Nepal (N = 242) and Seattle (N = 45) had protective rubella antibody (P = 0.23). Two hundred and thirty-eight (93%) infants in Nepal had protective rubella antibody versus 44 (98%) in Seattle (P = 0.12). Continued surveillance will be necessary to ensure protective immunity, inform progress toward disease elimination in Nepal and avoid reemergence in the United States.

Rubella virus infections and immune status among pregnant women before the introduction of rubella vaccine in Amhara Regional State, Ethiopia

BackgroundRubella and its associated congenital anomalies have been greatly reduced in most developed countries through use of the rubella vaccine. However, the magnitude of the problem is underestimated and there are no well-established rubella/congenital rubella syndrome prevention and control strategies in many developing countries, including Ethiopia. The aim of this study was to determine the prevalence of rubella virus infections among pregnant women and their immune status before the introduction of rubella vaccine in Amhara Regional State, Ethiopia. MethodsA prospective cross-sectional study was conducted among pregnant women in Dessie, Felege-Hiwot, and University of Gondar referral hospitals, from December 2015 to February 2017. After obtaining written informed consent, socio-demographic data, reproductive history, clinical manifestations, and the possible risk factors for rubella virus infections were collected using a structured questionnaire. The laboratory analysis of rubella-specific antibodies was done using an enzyme-linked immunoassay method on venous blood samples. Data were entered and analyzed using IBM SPSS Statistics version 20. Binary logistic regression was used to determine the strength of association between the dependent variables and covariates. ResultsA total of 600 pregnant women were included in the study. Their mean age was 26.4±5years (range 16–40 years). The overall seroprevalence of rubella infection was 89%. Of the total study participants, 9.5% were positive for rubella-specific IgM antibody, which indicates acute/recent rubella virus infection. In contrast, 79.5% of them had protective levels of rubella-specific IgG antibody and were immune as a result of previous wild-type rubella infection. However, 11% of the pregnant women were negative for both rubella-specific antibodies; these women represent the susceptible group. ConclusionsA large number of pregnant women had acute/recent rubella virus infections at the time of data collection, indicating that the virus is endemic in the study area. More than a tenth of pregnant women were found to be susceptible to acquiring the infection in future pregnancies, with the possible risk of rubella-associated congenital anomalies. Hence screening of all women of child-bearing age before conception and during pregnancy might reduce the devastating effects of the virus on the developing fetus.

Seroprevalence of rubella-specific antibodies and factors associated with its transmission among children aged 0-10 years, in Jos, Nigeria, 2016

Introduction: rubella infection during early pregnancy may result in congenital rubella syndrome (CRS), stillbirth or miscarriage. Children often are the source of infection to their mothers. Routine rubella vaccination is yet to be introduced in Nigeria. We determined the sero-prevalence of rubella-specific antibodies in school children 0-10 years and factors associated with its transmission in Jos.