Multiplex Bead Assay for the Serological Surveillance of Measles and Rubella.

There is increasing interest in evaluating antibody responses to multiple antigen targets in a single assay. Immunity to measles and rubella are often evaluated together because immunity is provided through combined vaccines and because routine immunization efforts and surveillance for measles and rubella pathogens are combined in many countries. The multiplex bead assay (MBA) also known as the multiplex immunoassay (MIA) described here combines the measurement of measles- and rubella-specific IgG antibodies in serum quantitatively according to international serum standards and has been successfully utilized in integrated serological surveillance.

Seroprevalence of Toxoplasma gondii, Rubella, Group A Streptococcus, CMV and HSV-1 in COVID-19 Patients with Vitamin D Deficiency.

<b>Background and Objective:</b> In recent years, respiratory tract viral infections have caused many pandemics that impact the whole world. To investigate the seropositivity of <i>Toxoplasma gondii</i>, rubella, CMV, HSV-1 and group A <i>Streptococcus</i> in recovered COVID-19 patients and correlate these findings with vitamin D levels. <b>Materials and Methods:</b> A total of 417 COVID-19 patients with diarrhoea were enrolled in this study. Vitamin D and seroprevalence for <i>Toxoplasma gondii</i>, rubella, CMV, HSV-1 and group A <i>Streptococcus</i> were evaluated and correlated. <b>Results:</b> It was found that recent infection in COVID-19 patients with HSV-1, rubella, <i>Toxoplasma</i> and CMV, respectively. IgG was detected indicating the development of adaptive immunity with all microbes. <b>Conclusion:</b> Current study detected a correlation between vitamin D levels and HSV-1 and no correlation between this infection and vitamin D deficiency with the other microbes.

Analysis of Morphological Changes in the CNS and Internal Organs of Macaca mulatta Monkeys after Intracerebral Injection of a Low-Attenuated Rubella Virus Strain.

We studied the localization and severity of morphological changes in CNS and internal organs of animals intacerebrally infected with a low-attenuated rubella virus strain "Orlov-14". The data obtained can be used as morphological criteria reflecting low level of attenuation of rubella virus strains to improve the control of the safety of attenuated strains of live rubella vaccines.

Rubella Eradication: Not Yet Accomplished, but Entirely Feasible.

Rubella virus is the most teratogenic virus known to science and is capable of causing large epidemics. The RA 27/3 rubella vaccine, usually combined with measles vaccine, has eliminated rubella and congenital rubella syndrome from much of the world, notably from the Western Hemisphere. Except in immunosuppressed individuals, it is remarkably safe. Together with rubella vaccine strains used in China and Japan, eradication of the rubella virus is possible, indeed more feasible than eradication of measles or mumps.

Transcriptional signatures associated with rubella virus-specific humoral immunity after a third dose of MMR vaccine in women of childbearing age.

Multiple factors linked to host genetics/inherent biology play a role in interindividual variability in immune response outcomes after rubella vaccination. In order to identify these factors, we conducted a study of rubella-specific humoral immunity before (Baseline) and after (Day 28) a third dose of MMR-II vaccine in a cohort of 109 women of childbearing age. We performed mRNA-Seq profiling of PBMCs after rubella virus in vitro stimulation to delineate genes associated with post-vaccination rubella humoral immunity and to define genes mediating the association between prior immune response status (high or low antibody) and subsequent immune response outcome. Our study identified novel genes that mediated the association between prior immune response and neutralizing antibody titer after a third MMR vaccine dose. These genes included the following: CDC34; CSNK1D; APOBEC3F; RAD18; AAAS; SLC37A1; FAS; and JAK2. The encoded proteins are involved in innate antiviral response, IFN/cytokine signaling, B cell repertoire generation, the clonal selection of B lymphocytes in germinal centers, and somatic hypermutation/antibody affinity maturation to promote optimal antigen-specific B cell immune function. These data advance our understanding of how subjects' prior immune status and/or genetic propensity to respond to rubella/MMR vaccination ultimately affects innate immunity and humoral immune outcomes after vaccination.

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.

Genetic and antigenic characterization of wild type rubella viruses isolated from India.

Rubella, is a contagious disease caused by Rubella virus (RuV) that manifests as fever with skin-rashes in children and adults along with complications in pregnant women. WHO-SEAR has set a target for Rubella elimination by 2023. This is the first report of antigenic characterization and genome sequencing of nine RuVs sampled during 1992, 2007-9, and 2015-17 from four Indian states. Comparative analysis of Indian RuVs (2B) with that of global isolates and vaccine strain RA 27/3 (1a) revealed that the observed mutations in structural proteins have no major impact on the 3D structure, function and antigenicity. Indian RuVs formed three major clusters (Pune-1992, Kannur-2009 and Chitradurg-2007) in genome-based phylogeny of global isolates. Neutralizing antibody titers in a panel of serum samples from measles negative cases were significantly higher to the vaccine strain compared to a wild-type 2B isolate (Kannur) with concordance of 91.9%, thereby substantiating the use of current vaccines.

Rubella Immunity among Italian Female Healthcare Workers: A Serological Study.

Rubella, also known as German measles or three-day measles, is an infectious disease caused by virus of the genus Rubivirus, which may be prevented by vaccination. The infection is potentially dangerous for non immune subjects, although 20-50% of infected subjects are asymptomatic. Healthcare workers (HCWs) have an increased potential exposure to rubella in comparison to the general population, putting them and their patients at risk of infection and its complications. In 2019, 20 cases of rubella have been reported in Italy. According to the Italian National Immunization and Prevention Plan, HCWs should provide a written certification of vaccination for rubella or serological evidence of protective antibodies. The aim of the study was to evaluate the rubella immunization status in female HCWs of the teaching hospital Policlinic Rome Tor Vergata (PTV) of childbearing age. For this purpose, we retrospectively checked the serologic values of rubella-specific IgG antibodies analyzing the clinical records of the HCWs of undergoing the occupational health surveillance program from January 1st to June1st 2020. Five hundred fourteen HCWs with a mean age of 23.19 (range 19-37, DS: 2.80) were included: 90.3% (464) showed a protective antibody titre. The mean value of the anti-rubella IgG was 49.59 IU/mL. Our study shows a non-protective anti rubella IgG titre in a substantial percentage of HCWs (9.7%). As vaccine protection decreases over the years and the risk of congenital rubella syndrome (CRS) in vaccinated subjects should not be underestimated, we suggest routine screening of the immunological status followed by the administration of a third dose of vaccine if the antibody titre becomes non-protective.

Relatives of rubella virus in diverse mammals.

Since 1814, when rubella was first described, the origins of the disease and its causative agent, rubella virus (Matonaviridae: Rubivirus), have remained unclear1. Here we describe ruhugu virus and rustrela virus in Africa and Europe, respectively, which are, to our knowledge, the first known relatives of rubella virus. Ruhugu virus, which is the closest relative of rubella virus, was found in apparently healthy cyclops leaf-nosed bats (Hipposideros cyclops) in Uganda. Rustrela virus, which is an outgroup to the clade that comprises rubella and ruhugu viruses, was found in acutely encephalitic placental and marsupial animals at a zoo in Germany and in wild yellow-necked field mice (Apodemus flavicollis) at and near the zoo. Ruhugu and rustrela viruses share an identical genomic architecture with rubella virus2,3. The amino acid sequences of four putative B cell epitopes in the fusion (E1) protein of the rubella, ruhugu and rustrela viruses and two putative T cell epitopes in the capsid protein of the rubella and ruhugu viruses are moderately to highly conserved4-6. Modelling of E1 homotrimers in the post-fusion state predicts that ruhugu and rubella viruses have a similar capacity for fusion with the host-cell membrane5. Together, these findings show that some members of the family Matonaviridae can cross substantial barriers between host species and that rubella virus probably has a zoonotic origin. Our findings raise concerns about future zoonotic transmission of rubella-like viruses, but will facilitate comparative studies and animal models of rubella and congenital rubella syndrome.

Prevalence of herpes -, measles morbillivirus-, parvovirus B19 - and rubella viruses immunoglobulin G among women with chronic hepatitis B of reproductive age in Denmark: A cross-sectional study.

OBJECTIVES: The aim of this study was to investigate whether the seroprevalence of IgG antibodies against seven viruses (cytomegalovirus, herpes simplex virus 1&2, measles morbillivirus, parvovirus B19, rubella, and varicella-zoster virus), which can potentially compromise maternal and fetal wellbeing, differs based on country of origin among women with chronic hepatitis B (CHB). METHOD: This study was a single-center, hospital-based cross-sectional study. The study included women with CHB 15-45 years of age, included in the Danish Database for Hepatitis B and C. Seroprevalence estimates were calculated with a 95% confidence interval and were compared between age groups, regions of origin, and to the general population. RESULTS: 177 women were included in the study. Overall, the seroprevalences of antibodies were similar among women with CHB with origin outside Denmark and compared to the general population in Denmark, but there was a notable difference in the seroprevalence of antibodies against herpes simplex 2 between women from Africa (37.1% CI 95% 22.0;55.1) and women from the Middle East (2.5% CI 95% 0.1;14.7). CONCLUSION: Women with CHB whose origin is outside Denmark do not appear to differ, based on origin, or be at greater risk of acquiring these viruses during pregnancy than their Danish counterparts.

Rubella IgM epidemiology in the pre-rubella vaccination era in Uganda.

BACKGROUND: Control of Rubella and Congenital Rubella Syndrome using vaccination has shown great success in the America's. Uganda is due to introduce the Rubella vaccine however the magnitude of transmission is not well documented. Therefore this study was done to determine IgM sero-prevalance for Rubella in order to help monitor vaccine effectiveness post introduction of the vaccine in routine vaccination programme. METHODS: A retrospective review of suspected measles cases data for the reporting period January 2007 to December 2016 in Uganda was Done. rubella IgM testing was done on 15,296 of the cases and the data was analyzed using STATA version 13. RESULTS: In total 15,296 cases were tested and 4255 (27.8%) tested positive and among females aged 15-49 years 88 out of 322 (27%) tested positive. The age distribution range was 0-80 years, rubella IgM positivity was reported in all the 15 regions of Uganda and throughout the ten year period in every month. Age group 5-15 years had OR 2.5 p-value < 0.001 of being rubella IgM positive compared to age < 5 years and testing measles IgM negative OR 6.3 p-value < 0.001. CONCLUSION: Rubella is endemic in Uganda and although rubella IgM positivity is highest in the age 5-15 years even the younger, older and women of reprodutive age are affected. This means the risk of Congenital Rubella Syndrome is high hence the need to introduce the rubella vaccine for infants and pregnant mothers and continued surveillance to enhance its control.

Impact of vaccination on measles, mumps, and rubella antibody titers in Japanese healthcare workers: An observational study.

Given the complicated history of Japan's National Immunization Program, a significant proportion of Japanese people including healthcare workers (HCWs) still lack adequate immunity against measles, mumps, and rubella (MMR), resulting in occasional outbreaks. In 2014, the Japanese Society of Infection Prevention and Control (JSIPC) published vaccination guidelines for HCWs. We evaluated antibody titers before and after MMR vaccination in HCWs at the Nara Medical University Hospital, the attainment rate of the target antibody titers defined by the JSIPC guidelines, and the safety of vaccines. We measured MMR antibody titers in HCWs, followed by inoculation with the respective monovalent vaccines and/or trivalent MMR (tMMR) vaccine according to the JSIPC guidelines. Among 467 HCWs evaluated, antibody titers against measles and mumps measured using the IgG-enzyme immunoassay increased from 11.0 [interquartile range (IQR): 8.0-13.6] to 13.7 (IQR: 11.3-16.9; P < 0.001) and from 2.8 (IQR: 2.1-3.5) to 4.8 (IQR: 3.7-5.7; P < 0.001), respectively. By evaluating a logarithmic value of log2(X + 1) converted from an antibody titer X, antibody titers against rubella measured using the hemagglutination assay increased from 3.2 (IQR: 0-4.1) to 6.0 (IQR: 4.6-8.0; P < 0.001). Antibody titer elevated following tMMR vaccination was lower than that following monovalent vaccination in a single dose of the measles-containing, a single dose of the mumps-containing, and two doses of rubella-containing vaccine groups (P = 0.01, 0.01, and <0.001, respectively). After vaccination, 20.0%, 61.5%, and 46.2% of HCWs attained target antibody titers specified by the JSIPC guidelines for measles, rubella, and mumps, respectively. The systemic response in female HCWs who underwent monovalent mumps vaccination was statistically higher than that in others. Although the vaccination program for HCWs according to the JSIPC guidelines caused increased MMR antibody titers, the rates of attaining the target criteria were low.

Rubella seroepidemiology among Korean women: Two decades after a combined vaccination strategy.

OBJECTIVES: The aim was to examine rubella seronegativity among women of childbearing age after the introduction of rubella-containing vaccine (RCV) among teenage girls and universal MMR programs in South Korea. METHODS: The serum IgG data of 72 114 women aged 20-49 years, who had undergone rubella antibody testing at the Gangnam CHA Medical Center between 2004 and 2018, were examined. A serum IgG level <10.0 IU/ml was considered negative. The study population was divided into three cohorts based on the vaccination policy: cohort 1, 1955-1976 (no national immunization program); cohort 2, 1977-1985 (national rubella only vaccination for high schoolers); cohort 3, 1986-1993 (combination strategy). We compared the rate of seronegativity and the adjusted odds ratio (OR) of seronegativity of each cohort. RESULTS: The overall proportion of seronegative women decreased significantly, from 6.1% in 2004 to 2.5% in 2018 (Kendall tau = -0.89, p < 0.001). The rate of seronegativity was highest among women who were not targeted for national immunization (born in 1955-1977, 5.2%), while it was lowest among candidates receiving routine and catch-up vaccinations (born in 1986-1993, 2.2%). When controlling for the effect of age and year of testing, the OR for seronegativity was lower for cohort 2 (adjusted OR 0.68, 95% confidence interval (CI) 0.60-0.76) and cohort 3 (OR 0.55, 95% CI 0.40-0.75) when compared to cohort 1. CONCLUSIONS: Women who were covered by either vaccination program were less susceptible to rubella infection, supporting the value of both approaches. The study findings will serve as empirical evidence for an immunization program targeted towards young women and children.

Immunotherapy with DNA vaccine and live attenuated rubella/SIV gag vectors plus early ART can prevent SIVmac251 viral rebound in acutely infected rhesus macaques.

Anti-retroviral therapy (ART) has been highly successful in controlling HIV replication, reducing viral burden, and preventing both progression to AIDS and viral transmission. Yet, ART alone cannot cure the infection. Even after years of successful therapy, ART withdrawal leads inevitably to viral rebound within a few weeks or months. Our hypothesis: effective therapy must control both the replicating virus pool and the reactivatable latent viral reservoir. To do this, we have combined ART and immunotherapy to attack both viral pools simultaneously. The vaccine regimen consisted of DNA vaccine expressing SIV Gag, followed by a boost with live attenuated rubella/gag vectors. The vectors grow well in rhesus macaques, and they are potent immunogens when used in a prime and boost strategy. We infected rhesus macaques by high dose mucosal challenge with virulent SIVmac251 and waited three days to allow viral dissemination and establishment of a reactivatable viral reservoir before starting ART. While on ART, the control group received control DNA and empty rubella vaccine, while the immunotherapy group received DNA/gag prime, followed by boosts with rubella vectors expressing SIV gag over 27 weeks. Both groups had a vaccine "take" to rubella, and the vaccine group developed antibodies and T cells specific for Gag. Five weeks after the last immunization, we stopped ART and monitored virus rebound. All four control animals eventually had a viral rebound, and two were euthanized for AIDS. One control macaque did not rebound until 2 years after ART release. In contrast, there was only one viral rebound in the vaccine group. Three out of four vaccinees had no viral rebound, even after CD8 depletion, and they remain in drug-free viral remission more than 2.5 years later. The strategy of early ART combined with immunotherapy can produce a sustained SIV remission in macaques and may be relevant for immunotherapy of HIV in humans.

Comparative studies of rubella virus immunity of immunized and non-immunized pregnant women visiting Kogi State University Teaching Hospital, Anyigba, North Central Nigeria.

Rubella is endemic worldwide and poses a serious threat to infants and pregnant women. Although the disease has been widely reported in parts of the country, there is currently no documented evidence of the disease in Anyigba. A comparative study of rubella immunity was conducted among immunized and non-immunized pregnant women visiting the Kogi State University Teaching Hospital, Anyigba. In a cross-sectional study, blood samples collected from 300 pregnant women (immunized = 127; non-immunized = 173) were tested for rubella antibodies using ELISA kit. Overall, anti-rubella-IgM and IgG seroprevalence rates of 38 (12.7%) and 83 (27.7%) were detected. Seventy (55.1%) of the immunized against 13 (7.5%) of non-immunized women had detectable IgG. The non-immunized women were significantly more seropositive for IgM than the immunized who recorded higher prevalence of IgG. Immunized and non-immunized women aged 23-32 years had higher IgG and IgM positivity rates. The difference in IgM and IgG seropositivity rates in relation to vaccination was statistically significant (P < 0.05) between the immunized (0.8%, 55.1%) and vaccine-naïve subjects (21.4%, 7.5%). Low level of awareness and high susceptibility to rubella virus infection especially among the non-immunized women was confirmed in study area, thus the need for government to strengthen education of masses and to make rubella vaccination freely available for women of childbearing age.

Epidemiology of acute rubella infection in Zambia during the pre-vaccination period (2005-2016) as a baseline for monitoring rubella epidemiology in the post-rubella vaccine introduction era.

BACKGROUND: Rubella is highly under reported in Zambia as in most sub-Saharan countries despite being a disease of major public health concern especially among women of childbearing age. In September 2016, Zambia introduced a combined measles-rubella vaccine in children 0-14 years. In this study, we estimated the proportion positive for acute rubella among suspected but negative measles cases between 2005 and 2016 and determined its correlates for monitoring rubella epidemiology post-rubella vaccine introduction. METHODS: In a retrospective study, 4497 measles IgM negative serum samples from 5686 clinically suspected measles cases were examined for rubella IgM antibodies using the Siemens, Enzygnost® ELISA kit at the national measles laboratory. Data on demographics, year and month of onset were extracted from the surveillance data. Multivariate logistic regression analysis using backward variable selection was conducted to determine independent predictors for acute rubella. The magnitude of association was estimated using adjusted odds ratio with a 95% confidence interval. RESULTS: Overall, a proportion of 29.2% (1313/4497) affecting mostly those between 5 and 24 years was determined. Only age, province, month and year were independently associated with acute rubella. The regional proportions varied from 21.8-37.3% peaking in the month of October. Persons in the age group 10-14 years (Adjusted Odds Ratio [AOR] = 2.43; 95% CI [2.01-2.95]) were more likely while those aged < 1 year less likely (AOR = 0.31; 95% CI [021-0.48]) to have acute rubella compared to those aged 25 years or older. Persons in 2010 were less likely (AOR = 0.12; CI [0.05, 0.28]) to have acute rubella compared to those in 2016. While acute rubella was more likely to occur between July and November compared to December, it was less likely to occur between February and May. CONCLUSIONS: Rubella virus was circulating in Zambia between 2005 and 2016 affecting mostly persons in the age group 5-24 years peaking in the hot dry season month of October. Although vaccination against rubella has been launched, these baseline data are important to provide a reference point when determining the impact of the vaccination program implemented.

Assessment of immune status against measles, mumps, and rubella in young Kuwaitis: MMR vaccine efficacy.

Seroprevalence studies on measles, mumps, and rubella immunoglobulin G (IgG) antibodies after the implementation of the measles-mumps-rubella (MMR) vaccine are lacking in Kuwait. This study is an age-stratified serological study to assess the herd immunity to measles, mumps, and rubella among the young Kuwaiti population to evaluate the effectiveness of the MMR vaccine. IgG antibody titers to mumps, measles, and rubella were determined with commercial immune-assay in serum samples of 1000 Kuwaitis aged 5 to 20 years. The highest level of seropositivity was to measles (94.6%), which was significantly higher in females than in males. The highest seronegativity was for mumps (29%). The percentage of the young Kuwaiti population who were serologically positive for all the components of the MMR vaccine was 47%, and 2% of the individuals were without any protective antibodies to measles, mumps, and rubella. Females aged 5 to 10 years were best protected to rubella; however, seronegativity in 8.2% of 11- to 20-year-old females makes them vulnerable to rubella virus infection and congenital complications during pregnancy. The study provided insight into the effect of the MMR vaccine on seroprevalence of antibodies against measles, mumps, and rubella in Kuwait, which will contribute to the global knowledge base of vaccine coverage and help to inform elimination strategies. The findings strengthen the need for a third dose of MMR vaccine and catch-up campaigns for the young Kuwaiti population to increase vaccination coverage and prevent waning immunity, especially among those who received only one dose of the vaccine during childhood.

Comparison of virological and serological methods for laboratory confirmation of rubella.

BACKGROUND: Work toward rubella elimination has accelerated globally. A reliable laboratory confirmation of rubella-suspected cases is required for effective surveillance in the rubella-elimination phase. The use of adequate specimens is a key to improving the quality of this surveillance. STUDY DESIGN: We conducted rubella virus (RUBV) isolation and RUBV genome or anti-RUBV IgM detection on 1023 specimens from 372 rubella- or measles-suspected cases collected through the national surveillance program in Sakai city of Osaka prefecture, Japan between 2011 and 2013. The resulting data were analyzed by specimen type, collection date, and immunological status. RESULTS: Among the three specimen types (throat swab, serum or plasma, and urine) collected through 10 days post-rash onset, the highest success rates for RUBV genome detection and RUBV isolation were obtained using throat swabs. In agreement with previous work, RUBV-specific IgM were undetectable in 50% of the rubella-confirmed cases until 3 days after rash onset. The success rates of RUBV genome detection and RUBV isolation declined in association with the appearance of RUBV-specific antibodies in blood, especially in serum, plasma, or urine samples. CONCLUSION: Throat swabs are the most optimal specimen types for both RUBV genome detection and RUBV isolation; serum/plasma samples may be suboptimal, especially for RUBV isolation. The findings from this study will provide useful information for improving laboratory surveillance for rubella in the elimination phase.