Development of a real-time fluorescent reverse transcription loop-mediated isothermal amplification assay with quenching primers for rapid detection of rubella virus.

Rubella virus infection during early pregnancy sometimes causes severe birth defects termed congenital rubella syndrome. Although there are safe and effective live-attenuated vaccines, rubella has only been certified as eliminated in the Americas within the six World Health Organization regions. Rubella remains an endemic disease in many regions, and outbreaks occur wherever population immunity is insufficient. There are two main methods for diagnosis of rubella: detection of anti-rubella IgM antibodies by enzyme immunoassay and detection of the viral genome by real-time RT-PCR. Both of these methods require substantial time and effort. In the present study, a rapid rubella detection assay using real-time fluorescent reverse transcription loop-mediated isothermal amplification with quenching primers was developed. The time required for the new assay was one-half that required for a real-time RT-PCR assay. The assay had 93.6% positive percent agreement and 100% negative percent agreement for clinical specimens compared with the real-time RT-PCR assay. The new assay is considered useful for diagnosis of rubella in areas where rubella is endemic.

Case report: Rubella virus-associated cutaneous granuloma in an adult with TAP1 deficiency.

Rubella virus-associated granulomas commonly occur in immunocompromised individuals, exhibiting a diverse range of clinical presentations. These manifestations can vary from predominantly superficial cutaneous plaques or nonulcerative nodules to more severe deep ulcerative lesions, often accompanied by extensive necrosis and significant tissue destruction. TAP1 deficiency, an exceedingly rare primary immune-deficiency disorder, presents with severe chronic sino-pulmonary infection and cutaneous granulomas. This report highlights the occurrence of rubella virus-associated cutaneous granulomas in patients with TAP1 deficiency. Notably, the pathogenic mutation responsible for TAP1 deficiency stems from a novel genetic alteration that has not been previously reported. This novel observation holds potential significance for the field of diagnosis and investigative efforts in the context of immunodeficiency disorders.

HLA Associations of Intrathecal IgG Production against Specific Viruses in Multiple Sclerosis.

OBJECTIVE: Specific human leucocyte antigen (HLA) alleles are not only associated with higher risk to develop multiple sclerosis (MS) and other autoimmune diseases, but also with the severity of various viral and bacterial infections. Here, we analyzed the most specific biomarker for MS, that is, the polyspecific intrathecal IgG antibody production against measles, rubella, and varicella zoster virus (MRZ reaction), for possible HLA associations in MS. METHODS: We assessed MRZ reaction from 184 Swiss patients with MS and clinically isolated syndrome (CIS) and 89 Swiss non-MS/non-CIS control patients, and performed HLA sequence-based typing, to check for associations of positive MRZ reaction with the most prevalent HLA alleles. We used a cohort of 176 Swedish MS/CIS patients to replicate significant findings. RESULTS: Whereas positive MRZ reaction showed a prevalence of 38.0% in MS/CIS patients, it was highly specific (97.7%) for MS/CIS. We identified HLA-DRB1*15:01 and other tightly linked alleles of the HLA-DR15 haplotype as the strongest HLA-encoded risk factors for a positive MRZ reaction in Swiss MS/CIS (odds ratio [OR], 3.90, 95% confidence interval [CI] 2.05-7.46, padjusted = 0.0004) and replicated these findings in Swedish MS/CIS patients (OR 2.18, 95%-CI 1.16-4.02, padjusted = 0.028). In addition, female MS/CIS patients had a significantly higher probability for a positive MRZ reaction than male patients in both cohorts combined (padjusted <0.005). INTERPRETATION: HLA-DRB1*15:01, the strongest genetic risk factor for MS, and female sex, 1 of the most prominent demographic risk factors for developing MS, predispose in MS/CIS patients for a positive MRZ reaction, the most specific CSF biomarker for MS. ANN NEUROL 2024;95:1112-1126.

Crystal structure and biochemical activity of the macrodomain from rubella virus p150.

Rubella virus encodes a nonstructural polyprotein with RNA polymerase, methyltransferase, and papain-like cysteine protease activities, along with a putative macrodomain of unknown function. Macrodomains bind ADP-ribose adducts, a post-translational modification that plays a key role in host-virus conflicts. Some macrodomains can also remove the mono-ADP-ribose adduct or degrade poly-ADP-ribose chains. Here, we report high-resolution crystal structures of the macrodomain from rubella virus nonstructural protein p150, with and without ADP-ribose binding. The overall fold is most similar to macroD-type macrodomains from various nonviral species. The specific composition and structure of the residues that coordinate ADP-ribose in the rubella virus macrodomain are most similar to those of macrodomains from alphaviruses. Isothermal calorimetry shows that the rubella virus macrodomain binds ADP-ribose in solution. Enzyme assays show that the rubella virus macrodomain can hydrolyze both mono- and poly-ADP-ribose adducts. Site-directed mutagenesis identifies Asn39 and Cys49 required for mono-ADP-ribosylhydrolase (de-MARylation) activity.IMPORTANCERubella virus remains a global health threat. Rubella infections during pregnancy can cause serious congenital pathology, for which no antiviral treatments are available. Our work demonstrates that, like alpha- and coronaviruses, rubiviruses encode a mono-ADP-ribosylhydrolase with a structurally conserved macrodomain fold to counteract MARylation by poly (ADP-ribose) polymerases (PARPs) in the host innate immune response. Our structural data will guide future efforts to develop novel antiviral therapeutics against rubella or infections with related viruses.

Rubella virus chronic inflammatory disease and other unusual viral phenotypes in inborn errors of immunity.

Infectious susceptibility is a component of many inborn errors of immunity. Nevertheless, antibiotic use is often used as a surrogate in history taking for infectious susceptibility, thereby disadvantaging patients who present with viral infections as their phenotype. Further complicating clinical evaluations are unusual manifestations of viral infections which may be less familiar that the typical respiratory viral infections. This review covers several unusual viral phenotypes arising in patients with inborn errors of immunity and other settings of immune compromise. In some cases, chronic infections lead to oncogenesis or tumor-like growths and the conditions and mechanisms of viral-induced oncogenesis will be described. This review covers enterovirus, rubella, measles, papillomavirus, and parvovirus B19. It does not cover EBV and hemophagocytic lymphohistiocytosis nor lymphomagenesis related to EBV. EBV susceptibility has been recently reviewed. Our goal is to increase awareness of the unusual manifestations of viral infections in patients with IEI and to describe treatment modalities utilized in this setting. Coincidentally, each of the discussed viral infections can have a cutaneous component and figures will serve as a reminder of the physical features of these viruses. Given the high morbidity and mortality, early recognition can only improve outcomes.

Rubella virus genotype 2B endemicity and related utility of serum-based molecular characterization in Uganda.

There are 13 globally recognized rubella virus genotypes of which only 2 (1E and 2B) have been detected recently. The largest percentage of all reported rubella virus sequences come from China and Japan with Africa reporting limited data. In a bid to address the lack of rubella genotype data in Uganda and the World Health Organization Africa region, we sought to characterize rubella viruses retrospectively using sera collected from suspected measles patients that turned out rubella IgM positive.Seven sequences belonging to genotype 2B sub-lineage 2B-L2c were obtained. These sequences clustered with other genotype 2B sequences previously reported from Uganda. None of the other genotypes (1E and 1G) reported from Uganda in the earlier years were detected. In addition, none of the sequences were obtained after the introduction of the measles-rubella containing vaccine. The above highlight the need for continuous rubella virological surveillance to confirm interruption of endemic rubella genotype circulation.

[Molecular epidemiological study on rubella virus circulating in Yunnan Province during 2011-2021].

Objective: To understand the genotype distribution and transmission pattern of rubella virus (RuV) circulating in Yunnan Province. Methods: Throat swab samples were collected from rubella outbreaks and sporadic cases in nine prefectures/cities of Yunnan Province from 2011 to 2021. Virus isolation, amplification of target genes and sequence determination were performed on the RuV-positive samples. The genotypes and lineages of Yunnan strains were determined by comparing them with the reference strains, and further phylogenetic analysis was performed with Yunnan strains and strains circulating in other provinces of China during the same period. Results: RuV circulating in Yunnan province during 2011-2021 showed significant genetic diversity, and three lineages, 1E-L1, 2B-L1 and 1E-L2, were detected. Two lineage-switches were also identified, including the conversion of 1E-L1 to 2B-L1 between 2012 and 2013, and the replacement of 2B-L1 to 1E-L2 after 2018. The time of the switches was basically consistent with the outbreak in Yunnan province in 2012 and the time of the rubella reemergence and epidemic between 2018 and 2019. The amino acid sequence of RuV virus strains in Yunnan province was highly conserved, and no important functional regions were changed. Conclusions: The transmission pattern of RuV in Yunnan province is generally consistent with the epidemic trend of RuV in other provinces of China.

Shedding of rubella virus in postsymptomatic individuals; viral RNA load is a potential indicator to estimate candidate patients excreting infectious rubella virus.

BACKGROUND: Since the first isolation of rubella virus (RuV) in 1962, comprehensive data regarding the quantitative evaluation of RuV shedding remain unavailable. In this study, we evaluated the shedding of viral RNA and infectious virus in patients with acute RuV infection. STUDY DESIGN: We analyzed 767 specimens, including serum/plasma, peripheral blood mononuclear cells (PBMCs), throat swabs, and urine, obtained from 251 patients with rubella. The viral RNA load and the presence of infectious RuV were determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and virus isolation. RESULTS: Virus excretion peaked 0-2 days after rash onset and decreased over time. The median viral RNA load dropped to an undetectable level on day 3 after rash onset in serum/plasma, day 2 in PBMCs, days 10-13 in throat swabs, and days 6-7 in urine. Infectious virus could be isolated for up to day 2 after rash onset in serum/plasma, day 1 in PBMCs, days 8-9 in throat swabs, and days 4-5 in urine. The minimum viral RNA load that allowed virus isolation was 961 copies/mL in serum/plasma, 784 copies/mL in PBMCs, 650 copies/mL in throat swabs, and 304 copies/mL in urine. A higher viral RNA load indicated a higher likelihood of the presence of infectious virus. CONCLUSION: These findings would contribute to improve algorithms for rubella surveillance and diagnosis. In addition, this study indicates that the results of RT-qPCR enable efficient rubella control by estimating candidate patients excreting infectious virus, which could help prevent viral transmission at an early stage and eliminate rubella ultimately.

A Biotechnological Review on Patents Applied to Rubella Diagnosis.

BACKGROUND: Rubella, caused by the Rubella virus (RV), is considered a mild self-limited illness. However, RV has teratogenic potential. Laboratory investigation plays an important role in both diagnosis and surveillance of the disease. The main methods for diagnosing Rubella are serological assays for the detection of specific IgM and molecular assays for detecting viral RNA. However, some laboratories perform IgG avidity testing, virus isolation and analysis of genetic sequence as tools to help Rubella eradication. The importance of the diagnosis of Rubella involves the appropriate treatment of the disease, because the Rubella clinical symptoms may be similar to those of other diseases, and the population monitoring to avoid new emergent cases. This study addresses different methods of diagnosing Rubella and contributes as a source of knowledge to assist health systems in controlling the disease. OBJECTIVE: The main objective of this study was to review the available patents regarding Rubella diagnosis published in intellectual property databases, and provides an overview of the technologies available for the diagnosis of Rubella. METHOD: The search strategy was based on the keywords searched separately or together using a Boolean operator either in the patent title or abstract the time interval was restricted to patents filed or granted from January 2009 until February 2022. The database used was Google Patents. RESULTS: This study analyzed 24 patent documents regarding strategies for the diagnosis of Rubella. Of these, 15 patents disclose strategies for detecting Rubella antibodies, 7 patents the detection of Rubella virus nucleic acid, and 2 patents the production of antibodies applied in Rubella diagnosis. CONCLUSION: Rubella is still a public health problem in some countries, mainly those in development, especially due to congenital Rubella syndrome, which can cause malformation or fetal death. However, its diagnosis is challenging, due to similarity of symptoms with other diseases, and for this reason, laboratory diagnosis is essential. Studies like this encourage researchers and governments to invest in research to continue the development of new products, using different areas of biotechnology, to solve society's problems, especially diseases that have an impact on global health, such as Rubella.

Phylogenetic analysis of congenital rubella virus from Indonesia: a case report.

BACKGROUND: Rubella is a common inherited infection resulting in congenital cataracts and a significant cause of permanent vision loss in developing countries. In 2016, Indonesia had the highest number of congenital rubella syndrome (CRS) cases globally. Here, we report the first genotype of the rubella virus extracted from the eye lens from a child with congenital cataracts due to CRS. CASE PRESENTATION: A female neonate was delivered by an elective caesarean delivery with normal birth weight at term from a 24-year-old mother in the rural setting. The baby presented with bilateral congenital cataracts, small-moderate secundum atrial septal defect, severe supravalvular pulmonary stenosis, and profound bilateral hearing loss. She also had microcephaly and splenomegaly. The patient's serology showed persistent positive IgG for rubella virus at the age of four years and four months. Following extraction during cataract surgery, viral detection of the lenses identified the presence of rubella. Phylogenetic analysis confirmed that the virus was grouped into genotype 1E. CONCLUSIONS: Our study reports the first phylogenetic analysis of the rubella virus extracted from the eye lens of a child with CRS in Indonesia. The detection of the rubella virus from eye lenses is remarkably promising. Our findings also emphasize the importance of molecular epidemiology in tracking the origin of rubella infection toward achieving virus eradication.

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 low­0.8 (95% CI 0.4−1.3) cases per million people in 2021­whereas 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.

Molecular surveillance of rubella virus in Beijing, China during 2010-2021: Progress and challenges in rubella elimination.

Rubella is listed by the World Health Organization (WHO) as a disease that needs to be eliminated worldwide. The aim of this study was to understand the progress and challenges towards rubella elimination in Beijing, China, by analyzing molecular surveillance data combined with immunization and surveillance strategies as well as epidemiological data. With high immunization coverage under the 3-dose policy (8 months, 18 months, and 6 years) and supplementary immunization activities for the floating population, rubella incidence showed a downward trend since 2010, despite two epidemics that occurred in 2014-2015 and 2019. The reported rubella cases were generally concentrated in the age group of 15-34 years. Although citywide surveillance for congenital rubella syndrome (CRS) has been carried out since 2016, only one case has been confirmed by laboratory testing. Furthermore, molecular surveillance data showed that rubella viruses (RVs) circulating in Beijing during 2010-2020 were evidently heterogeneous; the domestic lineage 1E-L1 and multiple imported lineages, including 2B-L1, 1E-L2, and 2B-L2c, were identified in the last decade. Meanwhile, two lineage-related switches were determined, including the displacement of lineage 1E-L1 with lineage 2B-L1 around 2014 and the transition between lineage 2B-L1 and lineage 1E-L2 and 2B-L2c in 2018-2019. This RV transmission pattern was similar to that observed across the country, whereas lineages 1E-L1 and 2B-L2c were prevalent in Beijing for a shorter period. Overall, these results indicate the need to maintain routine immunization with rubella-containing vaccines, promote regular supplementaryimmunizationactivities, and enhance rubella and CRS surveillance even in order to accelerate rubella elimination in Beijing. Further, the existing immunization strategies must be optimized to further close the immunity gap.

Rubella Virus Triggers Type I Interferon Antiviral Response in Cultured Human Neural Cells: Involvement in the Control of Viral Gene Expression and Infectious Progeny Production.

The type I interferon (IFN) response is one of the primary defense systems against various pathogens. Although rubella virus (RuV) infection is known to cause dysfunction of various organs and systems, including the central nervous system, little is known about how human neural cells evoke protective immunity against RuV infection, leading to controlling RuV replication. Using cultured human neural cells experimentally infected with RuV RA27/3 strain, we characterized the type I IFN immune response against the virus. RuV infected cultured human neural cell lines and induced IFN-ß production, leading to the activation of signal transducer and activator of transcription 1 (STAT1) and the increased expression of IFN-stimulated genes (ISGs). Melanoma-differentiation-associated gene 5 (MDA5), one of the cytoplasmic retinoic acid-inducible gene I (RIG-I)-like receptors, is required for the RuV-triggered IFN-ß mRNA induction in U373MG cells. We also showed that upregulation of RuV-triggered ISGs was attenuated by blocking IFN-α/ß receptor subunit 2 (IFNAR2) using an IFNAR2-specific neutralizing antibody or by repressing mitochondrial antiviral signaling protein (MAVS) expression using MAVS-targeting short hairpin RNA (shRNA). Furthermore, treating RuV-infected cells with BX-795, a TANK-binding kinase 1 (TBK1)/I kappa B kinase ε (IKKε) inhibitor, robustly reduced STAT1 phosphorylation and expression of ISGs, enhancing viral gene expression and infectious virion production. Overall, our findings suggest that the RuV-triggered type I IFN-mediated antiviral response is essential in controlling RuV gene expression and viral replication in human neural cells.

Aqueous Humor Analysis in Overlapping Clinical Diagnosis of Cytomegalovirus and Rubella Virus Anterior Uveitis.

Background and Objectives: A cross-sectional single-center study was conducted to investigate the etiology in hypertensive anterior uveitis whose clinical features are not fully distinctive from cytomegalovirus or from rubella virus and to demonstrate the possible coexistence of both these viruses in causing anterior uveitis. Materials and Methods: The clinical charts of a cohort of patients with hypertensive viral anterior uveitis of uncertain origin consecutively seen in a single center from 2019 to 2022 were retrospectively reviewed; data on the clinical features, aqueous polymerase chain reaction, and antibody response to cytomegalovirus and rubella virus were collected. Results: Forty-three eyes of as many subjects with viral anterior uveitis of uncertain origin were included. Thirty-two patients had an aqueous polymerase chain reaction or antibody index positive to cytomegalovirus only, while 11 cases had an aqueous antibody response to both cytomegalovirus and rubella virus. This latter overlapping group had a statistically significant higher rate of hypochromia and anterior vitritis (p-value: 0.02 and < 0.001, respectively). Conclusions: The simultaneous presence of intraocular antibodies against cytomegalovirus and rubella virus could redefine the differential diagnosis of hypertensive viral anterior uveitis, demonstrating a possible "converged" immune pathway consisting in a variety of stimuli.

Improved diagnostic and multiplex RT-qPCR for detecting rubella viral RNA.

An examination of the nucleic acid sequence alignment of 48 full-length rubella virus genomes revealed that the 5' terminus of the genome is more conserved than the commonly used detection windows for rubella virus RNA located in the E1 protein coding region, suggesting that the 5' terminus could be a target for improving detection of all rubella virus genotypes. Two candidate primer sets were tested and the window between nucleotides (nts) 98 and 251 was found to have the greatest analytical sensitivity for detection of different genotypes. The new method had a limit of detection of four copies of rubella RNA per reaction with high specificity. The average coefficient variation of Ct was 2.2%. Concordance between the new method and currently used method, based on testing 251 clinical specimens collected from a rubella outbreak, was 99.4%. The assay was further improved upon by the incorporation of detection of both rubella virus RNA and mRNA from a cellular reference gene in a multiplex format. The multiplex format did not reduce the sensitivity or the reproducibility of rubella RNA detection and, of 60 specimens tested, the concordance between the single target and multiplex assays was 85.0%. To assess the utility of the multiplex assay for molecular surveillance, 62 rubella IgM positive serum samples from a rubella outbreak were tested, and eleven tested positive using the multiplex method while none were positive using the method targeting E1. These results show that the assay based on the new detection window near the 5' terminus of the genome can improve the detection of rubella virus for the purpose of molecular surveillance and case confirmation, with the added benefit of improved efficiency due to multiplexing.

Case Report: Rubella Virus-Induced Cutaneous Granulomas in Two Pediatric Patients With DNA Double Strand Breakage Repair Disorders - Outcome After Hematopoietic Stem Cell Transplantation.

We report two patients with DNA repair disorders (Artemis deficiency, Ataxia telangiectasia) with destructive skin granulomas, presumably triggered by live-attenuated rubella vaccinations. Both patients showed reduced naïve T cells. Rapid resolution of skin lesions was observed following hematopoietic stem cell transplantation. However, the patient with AT died due to complications of severe hepatic veno-occlusive disease 6 month after HSCT. Dried blood spots obtained after birth were available from this patient and showed absent T-cell receptor excision circles (TRECs). Therefore, newborn screening may help to prevent patients with moderate T-cell deficiency from receiving live-attenuated rubella vaccine potentially causing granulomas.

Rubella virus-associated uveitis: The essentiality of aqueous humor virological analysis.

AIMS / BACKGROUND: Rubella virus-associated uveitis (RVAU) classically presents with the clinical features of Fuchs uveitis syndrome (FUS). We report a series RVAU, and discuss the relevance of available diagnostic strategies, and how vaccination could potentially prevent disease. METHODS: We retrospectively included patients with RV-positive aqueous humor (AH) with RT-PCR and/or intraocular RV-IgG production, between January 2014 and December 2019. RV-IgG titers from AH and serum were compared with other virus-specific IgG titers (VZV and/or CMV and/or HSV-1), to determine the derived Goldmann-Witmer coefficient (GWC'). Clinical findings at presentation and during follow-up are reported, as well as the anti-RV vaccination status. RESULTS: All 13 included patients demonstrated intraocular synthesis of RV-IgG (median GWC': 9.5; 3.2-100). RV-RNA was detected in one patient while PCR results were negative for other HSV1, VZV and CMV. The mean delay in diagnosis was 13 ± 12.6 years, with an initial presentation of FUS in only 3 patients (23%). Only four patients had been vaccinated, but all after the recommended age. CONCLUSION: As RVAU is a pleiomorphic entity, virological analysis (RV RT-PCR and GWC') of aqueous humor is essential to improve the diagnosis and management of this entity. Improper vaccination against RV appears to be implicated in RVAU.

Association of Persistent Rubella Virus With Idiopathic Skin Granulomas in Clinically Immunocompetent Adults.

Importance: Vaccine-derived and wild-type rubella virus (RuV) has been identified within granulomas in patients with inborn errors of immunity, but has not been described in granulomas of healthy adults. Objective: To determine the association between RuV and atypical granulomatous inflammation in immune-competent adults. Design, Setting, and Participants: This case series, conducted in US academic dermatology clinics from January 2019 to January 2021, investigated the presence of RuV in skin specimens using RuV immunofluorescent staining of paraffin-embedded tissue sections, real-time reverse-transcription polymerase chain reaction, whole-genome sequencing with phylogenetic analyses, and cell culture by the US Centers for Disease Control and Prevention. Rubella immunoglobulin G, immunoglobulin M enzyme-linked immunoassay, and viral neutralization assays were performed for the sera of immunocompetent individuals with treatment refractory cutaneous granulomas and histopathology demonstrating atypical palisaded and necrotizing granulomas. Clinical immune evaluation was performed. Main Outcomes and Measures: Identification, genotyping, and culture of vaccine-derived and wild-type RuV within granulomatous dermatitis of otherwise clinically immune competent adults. Results: Of the 4 total immunocompetent participants, 3 (75%) were women, and the mean (range) age was 61.5 (49.0-73.0) years. The RuV capsid protein was detected by immunohistochemistry in cutaneous granulomas. The presence of RuV RNA was confirmed by real-time reverse-transcription polymerase chain reaction in fresh-frozen skin biopsies and whole-genome sequencing. Phylogenetic analysis of the RuV sequences showed vaccine-derived RuV in 3 cases and wild-type RuV in 1. Live RuV was recovered from the affected skin in 2 participants. Immunology workup results demonstrated no primary immune deficiencies. Conclusions and Relevance: The case series study results suggest that RuV (vaccine derived and wild type) can persist for years in cutaneous granulomas in clinically immunocompetent adults and is associated with atypical (palisaded and necrotizing type) chronic cutaneous granulomas. These findings represent a potential paradigm shift in the evaluation, workup, and management of atypical granulomatous dermatitis and raises questions regarding the potential transmissibility of persistent live RuV.

Development of a rapid, internally controlled, two target, real-time RT-PCR for detection of rubella virus.

Rubella surveillance in elimination setting relies on rapid molecular detection of the virus. In this study a multiplex real-time RT-PCR assay for the detection of rubella virus was validated. The assay includes three independent probes with unique reporter dyes for the simultaneous detection of the rubella viral coding regions for envelope glycoprotein E1 and non-structural p150 protein, and an endogenous control (human RNaseP). Using dilution series of synthetic RNAs, the limits of detection were determined to be at least 50 copies of rubella RNA. The assay is reproducible with low intra-assay and inter-assay coefficients of variation for both the E1 and the p150 targets. After testing 62 confirmed rubella positive and 165 rubella negative archival clinical samples, the sensitivity and specificity of the multiplex assay were 98.4 and 100 %, respectively. No cross reactivity was identified with clinical specimens positive for eleven other viruses. This multiplex assay successfully detected nine viral genotypes including the predominant genotypes 1E, 1G, 1J, and 2B as well as the 1a vaccine genotype.

Design of a chimaeric antigen and its use in the detection of IgG antibodies against rubella virus.

BACKGROUND: Rubella virus (RV) is the causative agent of rubella or German measles. Although most infections cause only mild self-limited measles-like illness, the infection in pregnant women can cause severe foetal malformation or even miscarriage, especially in the first 3 months of pregnancy. Therefore, it is of great practical significance to establish a simple and sensitive RV detection method. METHODS: The partial epitopes of the E1 and E2 proteins from Rubella Virus were selected as the target sites, the sequence of the selected antigenic sites of the E1 and E2 were linked by a linker. The expression plasmid P6T was constructed by inserting the gene into PET-32A + with a histidine Tag. The P6 protein was induced and expressed in Escherichia coli L21 (DE3) and purified by nickel column affinity. The protein P6 antigen was identified by Western blotting analysis, and an anti-P6 antibody ELISA was established to test known serum samples to evaluate the capability of this method. RESULTS: After purification, the concentration and purity of the protein P6 were 0.283 mg/mL and more than 80%, respectively. Western blotting analysis showed that the protein P6 could react with rubella virus positive serum. By ELISA, 36 negative sera and 58 positive sera were detected. The coincidence rate, specificity and sensitivity of the ELISA were 86.2%, 88.89% and 84.48%, respectively. The P6 ELISA with a kappa coefficient of 0.715, P < 0.05, indicated excellent consistency. CONCLUSIONS: The protein P6 with excellent antigenicity obtained from prokaryotic expression followed by chromatography purification could prove useful for early diagnosis of RV infection.